1. Field of the Invention
The present invention relates to a physical quantity conversion sensor and a motor control system using the physical quantity conversion sensor. More particularly, the invention relates to a physical quantity conversion sensor well suited for using magneto-resistance effect elements as sensors, and a motor control system using the physical quantity conversion sensor.
2. Description of the Related Art
In a servo control system, rotation angle sensors are necessary to implement feedback control by detecting the rotation angle. In addition, in brushless motor control, rotation angle sensors are necessary not only for the servo control system but also for others because the current has to be applied to coils of a motor in correspondence to the rotation angle of the motor.
Further, a high level of safety is required in the case the system using the rotation angle sensors are applied to, for example, x-by-Wire that controls the behavior of the automobile vehicle body through integral control of electric power steering, electric braking, and electrically-controlled throttle devices, a steering system, and a braking system. Conventionally, a redundant technique preliminarily including an excessive number of components has been widely employed to satisfy the requirement for such a high level of safety, that is, to detect abnormality.
The rotation angle sensor using magnetism includes sensor elements that output signals proportional to the sine (“sin”) and cosign (“cos”) of the rotation angle, and conversion processing sections that obtain the rotation angle from the signals proportional to the sine (“sin”) and cosign (“cos”) from the sensor elements. According to conventional technique, however, the components are mounted in discrete packages, or as described in Non-patent Publication 1 below (*), the components are all mounted in a single package.
As described in Non-patent Publication 1, the technique in which the sensor elements and conversion processing section are mounted in the single package is effective in cost reduction associated with reduction in size and the number of connections, and in reliability improvement. However, it is desired to further take extensibility in regard to “non-redundant configuration→redundant configuration” into consideration.
For application to a use case that requires a high reliability such as described above, redundancy is necessary for the conversion processing section to implement fault detection. On the other hand, however, in many cases, since the sensor elements output two signals proportional to the sine (“sin”) and cosign (“cos”) of the rotation angle, the sensor elements already have redundancy in a certain extent; that is, further redundancy is not necessary. For example, when the characteristic represented by “(sin θ)2+(cos θ)2=1” is utilized, whether a determination can be made whether the output of the respective sensor element is normal or abnormal. However, in the technique in which the sensor elements and the conversion processing section are mounted in the single package, two packages have to be preliminarily provided, as described in Non-patent Publication 1. That is, excessive redundancy has to be provided for the convenience of the mounting or implementation method. This leads to cost elevation.
An object of the present invention is to provide a redundantly configurable physical quantity conversion sensor and a motor control system using the physical quantity conversion sensor without increasing the cost.
In order to achieve the object, according to one embodiment of the present invention, there is provided a physical quantity conversion sensor including a first sensor element that outputs a first output signal in correspondence to a first physical quantity acting from the outside; a second sensor element that outputs a second output signal associated with the first output signal in correspondence to the first physical quantity acting from the outside; a first conversion processing section that converts the first output signal output from the first sensor element and the second output signal output from the second sensor element into the second physical quantity; and a second conversion processing section that converts the first output signal output from the first sensor element and the second output signal output from the second sensor element into the second physical quantity.
According to another embodiment of the present invention, there is provided a physical quantity conversion sensor including a first sensor element that outputs a first output signal in correspondence to a first physical quantity acting from the outside; a second sensor element that outputs a second output signal associated with the first output signal in correspondence to the first physical quantity acting from the outside; a first conversion processing section that converts the first output signal output from the first sensor element and the second output signal output from the second sensor element into the second physical quantity; and an output terminal that outputs an output of each of the first and second sensor elements to the outside of a first package. The first and second sensor elements and the first conversion processing section are arranged in the first package.
According to another embodiment of the present invention, there is provided a physical quantity conversion sensor including a first sensor element that outputs a first output signal in correspondence to a first physical quantity acting from the outside; a second sensor element that outputs a second output signal associated with the first output signal in correspondence to the first physical quantity acting from the outside; and a first conversion processing section that converts the first output signal output from the first sensor element and the second output signal output from the second sensor element into the second physical quantity; and a second conversion processing section that converts the first output signal output from the first sensor element and the second output signal output from the second sensor element into a third physical quantity associated with the second physical quantity.
According to another embodiment of the present invention, there is provided a physical quantity conversion sensor including a first sensor element that outputs a first output signal in correspondence to a first physical quantity acting from the outside; a second sensor element that outputs a second output signal associated with the first output signal in correspondence to the first physical quantity acting from the outside; a third sensor element that outputs the second output signal associated with the first output signal in correspondence to the first physical quantity acting from the outside; a first conversion processing section that converts the first output signal output from the first sensor element and the second output signal output from the second sensor element into the second physical quantity; and a second conversion processing section that converts the first output signal output from the first sensor element and the second output signal output from the third sensor element into a third physical quantity associated with the second physical quantity.
According to another embodiment of the present invention, there is provided a motor control system including a motor; a motor control device (means) that controls a rotation angle of the motor; a magnet that rotates with rotation of a rotation shaft of the motor; and a rotation angle sensor that detects a direction of magnetic flux lines generated by the magnet to thereby detect a rotation angle of the motor. The rotation angle of the motor is controlled in accordance with the rotation angle detected by the rotation angle sensor. The rotation angle sensor includes a first sensor element that outputs a first output signal in correspondence to a direction of the magnetic flux lines acting from the outside; a second sensor element that outputs a second output signal associated with the first output signal in correspondence to a direction of the magnetic flux lines acting from the outside; a first conversion processing section that converts the first output signal output from the first sensor element and the second output signal output from the second sensor element into a signal representing the rotation angle of the motor; and a second conversion processing section that converts the first output signal output from the first sensor element and the second output signal output from the second sensor element into the second physical quantity.
According to the present invention, the redundant configuration can be implemented without increasing the cost.
In the accompanying drawings:
The configuration of a redundantly configurable physical quantity conversion sensor of a first embodiment of the present invention will be described below with reference to
First, with reference to
Sensor elements 100-1 and 100-2 and a conversion processing section 200-1 are mounted or implemented inside of a package 70-1. The sensor element 100-1 outputs a signal 101-1 proportional to the sine (“sin”) of a rotation angle θ, and the sensor element 100-2 outputs a signal 101-2 proportional to the cosign (“cos”) of the rotation angle θ. However, the sensor elements 100-1 and 100-2, respectively, may output signals proportional to the sine (“sin”) and cosign (“cos”) of the rotation angle θ. The conversion processing section 200-1 executes conversion processing of the signal 101-1 proportional to the sine (“sin”) and the signal 101-2 proportional to the cosign (“cos”), whereby an estimated value φ201-1 of the rotation angle θ is obtained.
The sensor elements 100-1 and 100-2 each use giant magnetic resistance (GMR) elements, as described further below with reference to
The sensor elements 100-1 and 100-2 are arranged in the extension direction of, for example, a rotation shaft of a rotator (a rotation shaft of a motor (
In the present embodiment, the package 70-1 includes an output terminal 201-10 that outputs the estimated value φ201-1 of the rotation angle θ to the outside of the package 70-1. The package 70-1 further includes output terminals 101-10 and 101-2 that, respectively, output the signals 101-1 and 101-2 proportional to the sine (“sin”) and the cosign (“cos”) to the outside of the package 70-1.
The output terminals 101-10 and 101-20 are, respectively, lead pins 101-10 and 101-20 described further below with reference to
Example practical configurations of physical quantity conversion sensors of the present embodiment will be described herebelow with reference to
First, a first example practical configuration will be described hereinbelow with reference to
The sensor elements 100-1 and 100-2, respectively, are provided in separate chips, and are laminated on a circuit board or lead frame 71-1. Further, the conversion processing section 200-1 is fixed on the circuit board or lead frame 71-1. Leads are provided as the output terminals 101-10 and 101-20 on the side where the sensor elements 100-1 and 100-2 are located. Leads are provided as the output terminal 201-10 on the side where the conversion processing section 200-1 is located. The sensor elements 100-1 and 100-2, the conversion processing section 200-1, the circuit board or lead frame 71-1, the output terminals 101-10 and 101-20, and the output terminal 201-10 are integrally molded from resin, thereby configuring the package 70-1.
In the present example configuration of the physical quantity conversion sensor of the third embodiment of the present invention, the respective sensor elements 100-1 and 100-2 are laminated in separate chips, so that the probability of simultaneous faults in the sensor elements 100-1 and 100-2 can be reduced, i.e., the degree of independence of faults in the sensor elements 100-1 and 100-2 can be increased.
Next, a second example practical configuration will be described herebelow with reference to
In the present example configuration, the respective sensor elements 100-1 and 100-2 are provided in a common chip. Other configuration portions are identical to those shown in
In the present example configuration, positional and angular misalignments between the sensor elements 100-1 and 100-2 are minimized, so that accuracy is optimized to be highest.
Next, a third example practical configuration will be described herebelow with reference to
In the present example configuration, the respective sensor elements 100-1 and 100-2 are provided in separate chips, and are mounted on both sides of the circuit board or lead frame 71-1.
In the present configuration, the degree of independence in probability of simultaneous faults, i.e., faults, in the sensor elements 100-1 and 100-2 can be maximized. This is because the configuration is formed such that the circuit board or lead frame 71-1 is interposed between the sensor elements 100-1 and 100-2.
Next, a fourth example practical configuration will be described herebelow with reference to
In the present example configuration, the respective sensor elements 100-1 and 100-2 are provided in separate chips, and are mounted on both sides of the circuit board or lead frame substrate 71-1a. Leads are provided as the output terminals 101-10 and 101-20 on one of both of the sides. The sensor elements 100-1 and 100-2, the circuit board or lead frame 71-1a, and the output terminals 101-10 and 101-20 are integrally molded from resin, thereby configuring a package 70-1a (or “first package,” herebelow).
Further, the conversion processing section 200-1 is fixed to a circuit board or lead frame 71-1b. Leads are provided as the output terminal 201-10 and 201-20 on one of both of the sides. The conversion processing section 200-1, the circuit board or lead frame 71-1b, and the output terminal 201-10 are integrally molded from resin, thereby configuring a package 70-1b (or “second package,” herebelow).
Further, connection leads connect between the first and second packages 70-1a and 70-1b.
Next, a fifth example practical configuration will be described herebelow with reference to
In the present example configuration, the respective sensor elements 100-1 and 100-2 are provided in separate chips, and are mounted on both sides of the circuit board or lead frame substrate 71-1a. Leads are provided as the output terminals 101-10 and 101-20 on one of both of the sides. The sensor elements 100-1 and 100-2, the circuit board or lead frame 71-1a, and the output terminal 101-10 and 101-20 are integrally molded from resin, thereby configuring the first package 70-1a.
Further, the conversion processing section 200-1 is fixed to the circuit board or lead frame 71-1b. Leads are provided as the output terminals 201-10 and 201-20 on one of both of the sides. The conversion processing section 200-1, the circuit board or lead frame 71-1b, and the output terminal 201-10 are integrally molded from resin, thereby configuring the second package 70-1b.
Further, as shown in
Next, a physical quantity conversion sensor having a redundant configuration (or “redundantly configured physical quantity conversion sensor,” herebelow) according to a second embodiment of the present invention will be described with reference to
First, a basic construction of the physical quantity conversion sensor of the present embodiment will be described herebelow with reference to
The present example configuration includes a second package 70-2 in addition to the configuration shown in
The respective signals 101-1 and 101-2 proportional to the sine (“sin”) and the cosign (“cos”), which have been derived by the output terminals 101-10 and 101-20 to the outside of the package 70-1, are input into the inside of the second package 70-2 through input terminals 203-20 and 204-20 and are further input into the conversion processing section 200-2.
In the present embodiment, the conversion processing sections 200-1 and 200-2 are designed in compliance with common specifications. As such, as shown in
According to this example configuration, the outputs φ201-l and φ′201-2 of the respective redundantly configured conversion processing sections 200-1 and 200-2 are compared with one another, whereby faults of the respective conversion processing section 200-1, 200-2 can be detected.
Next, implementation or mounting of the physical quantity conversion sensor of the present embodiment will be described herebelow with reference to
First, a first example practical configuration will be described hereinbelow.
As shown in
As shown in
Next, a second practical configuration example will be described herebelow with reference to
As shown in
The second package 70-2 includes the conversion processing section 200-2 provided on leads 71-2. The second package 70-2 includes input terminals 203-20 and 204-20 on one side and an output terminal 201-20. The input terminal 203-20 inputs the signal 101-1 proportional to the sine (“sin”), the input terminal 204-20 inputs the signal 101-2 proportional to the cosign (“cos”), and the output terminal 201-20 outputs the estimated value φ201-1 of the rotation angle θ.
The packages 70-1a and 70-1b are arranged on one side of the circuit board 71, and the package 70-2 is arranged on the other side of the circuit board the 71. Then, through the through-hole 73 formed in the circuit board the 71, the output terminal 101-10 of the package 70-1 and the input terminal 203-20 of the package 70-2 can be interconnected, and the output terminal 101-20 of the package 70-1 and the input terminal 204-20 of the second package 70-2 can be interconnected.
Next, the leads of the lead frames that connect between the sensor elements 100-1 and 100-2 and the conversion processing sections 200-1 and 200-2 and signal allocation to bonding pads that electrically connect (or, simply “connect,” hereinbelow) signals to the conversion processing section 200-1 will be described with reference to
As further described below with reference to
More specifically, from the sensor element 100-1, a SIN_N signal 101-1n and a SIN_P signal 101-1p are output, and the VCC voltage and the GND voltage are supplied. Similarly, from the sensor element 100-2, a COS_N signal 101-2n and a COS_P signal 101-2p are output, and the VCC voltage and the GND voltage are supplied.
First signal allocation will be described herebelow with reference to
Reference is made to the respective cases shown in
As described with reference to, for example,
According to the arrangements described above, the output signals of the sensor elements 100-1 and 100-2 can be connected to the conversion processing section 200-1 by use of wiring patterns of the circuit board of the single layer and the leads of the lead frame. Thereby, the signals are input to input terminals of the conversion processing section 200-1, as follows:
the SIN_P signal 101-1p is input to a SIN_IN_P terminal 203-10p of the conversion processing section 200-1;
the SIN_N signal 101-1n is input to a SIN_IN_N terminal 203-10n of the conversion processing section 200-1;
the COS_P signal 101-2p is input to a COS_IN_P terminal 204-10p of the conversion processing section 200-1; and
the COS_N signal 101-2n is input to a COS_IN_N terminal 204-10n of the conversion processing section 200-1.
Inside of the conversion processing section 200-1, there is performed a conversion expressed below.
Next, second signal allocation will be described herebelow with reference to
Reference is made to, for example, the case where, as shown in
Thereby, the signals are input to the conversion processing section 200-1, as follows:
the COS_N signal 101-2n is input to the SIN_IN_P terminal 203-10p of the conversion processing section 200-1;
the COS_P signal 101-2p to the SIN_IN_N terminal 203-10n of the conversion processing section 200-1;
the SIN_N signal 101-1n to the COS_IN_P terminal 204-10p of the conversion processing section 200-1; and
the SIN_P signal 101-1p to the COS_IN_N terminal 204-10n of the conversion processing section 200-1.
Inside of the conversion processing section 200-2, there is performed a conversion expressed below.
Next, third signal allocation will be described herebelow.
In the case where, as shown in
Thus, as shown in
Descriptions made in regard to
In the present example, wiring layers 710 and 712 are formed on two layers on the obverse and reverse sides, in which the wiring layers are interconnected through via-holes 711. In order to secure an area for mounting of the sensor element 100-2 on the reverse face, the wiring pattern on the reverse face is formed in the manner that the signals 101-1 and 101-2 are connected to the output terminals 101-10 and 101-20 signal 101-2 by circumventing the area where the sensor element 100-2 is mounted. In the case the sensor element 100-2 is not mounted or three or more wiring layers are provided, connection of the signals can be accomplished in a minimum distance, without circumventing the area of the sensor element 100-2.
Next, a redundantly configured physical quantity conversion sensor according to a third embodiment of the present invention will be described herebelow with reference to
First, a basic construction of the physical quantity conversion sensor of the present embodiment will be described with reference to
In the present embodiment, the sensor elements 100-1 and 100-2 and the conversion processing sections 200-1 and 200-2 are mounted in a common package 70. The configuration may be such that the conversion processing section 200-2 is mounted or is not mounted. Depending on the type of configuration, the common package or package-forming mold, and the common circuit board or lead frame are used. Thereby, the configuration can be tailored to be usable either as a redundantly configured sensor (or, “redundant sensor,” hereinbelow) or as a non-redundantly configured sensor. For example, for a use case not requiring the redundancy, only the sensor elements 100-1 and 100-2 and conversion processing section 200-1 are mounted on the circuit board or lead frame. On the other hand, however, for a use case requiring the redundancy, the sensor elements 100-1 and 100-2 and the conversion processing sections 200-1 and 200-2 are mounted on the circuit board or lead frame.
Next, practical implementation examples of the physical quantity conversion sensor of the present embodiment will be described with reference to
First, a first example practical configuration will be described with reference to
In the present example configuration, the sensor elements 100-1 and 100-2 and conversion processing sections 200-1 and 200-2 are mounted by being laminated on the circuit board or lead frame 71-1.
Next, a second example practical configuration will be described with reference to
In the present example configuration, the respective sensor elements 100-1 and 100-2 and the respective conversion processing sections 200-1 and 200-2 are mounted on both sides of the circuit board or lead frame 71-1.
In the present example configuration, since the circuit board or lead frame 71-1 is interposed between the conversion processing sections 200-1 and 200-2, the degree of independence in probability of simultaneous faults, i.e., faults, in the conversion processing sections 200-1 and 200-2 is maximized.
Next, a third example practical configuration will be described herebelow with reference to
In the present example configuration, the sensor elements 100-1 and 100-2 and the conversion processing sections 200-1 and 200-2 can interconnected by the leads. In this configuration also, similarly as in the example configuration shown in
A redundantly configured physical quantity conversion sensor according to a fourth embodiment of the present invention will be described with reference to
As shown in
According to the present embodiment, even in the event that the conversion processing section 200-1, 200-2A has produced same outputs including an error resulting from, for example, a design related weak point, one of them is not the negative value thereof, so that the error can be detected. Consequently, the effect of double errors resulting from, for example, design related weak point can be prevented.
Further, as shown in
A redundantly configured physical quantity conversion sensor according to a fifth embodiment of the present invention will be described with reference to
In the present embodiment, the signals are input to the conversion processing section 200-1, as follows:
the signal 101-1 proportional to the sine (“sin”) from the sensor element 100-1 is input to a SIN signal input terminal of the conversion processing section 200-1; and
the signal 101-2 proportional to the cosine (“cos”) from the sensor element 100-2 is input to a COS signal input terminal of the conversion processing section 200-1.
On the other hand, signals are input to the conversion processing section 200-2, as follows:
the signal 101-2 proportional to the cosine (“cos”) from the sensor element 100-2 is input to a SIN signal input terminal of the conversion processing section 200-2; and
the signal 101-1 proportional to the sine (“sin”) from the sensor element 100-1 is input to a COS signal input terminal of the conversion processing section 200-2.
Thus, as compared to the examples such as shown in
The present embodiment can be applied to the conversion processing sections 200-1 and 200-2 shown in
An output φ of the conversion processing section 200-1 is represented as
The conversion processing section 200-2 executes a process similar to that of the conversion processing section 200-1. However, since the input signals are reverse, an output φ′ is represented as
According to the present embodiment, similarly as in the embodiment examples shown in
A redundantly configured physical quantity conversion sensor according to a sixth embodiment of the present invention will be described with reference to
In the present embodiment, the conversion processing sections 200-1 and 200-2, respectively, include diagnostic function sections 205-1 and 205-2. The diagnostic function sections 205-1 and 205-2, respectively, output diagnosis results 202-1 and 202-2.
As diagnosis contents of the diagnostic function sections 205-1 and 205-2, those as described in, for example, Japanese Patent Application No. 2006-307317 submitted in the past are utilized. The diagnostic function sections 205-1 and 205-2, respectively, provide the contents of processing that are substantially the same as the contents of conversion processing in the conversion processing sections 200-1 and 200-2. The diagnostic function sections 205-1 and 205-2 perform simplified conversion processes. More specifically, the diagnostic function sections 205-1 and 205-2, respectively, perform comparison between the results of the conversion processes in the conversion processing sections 200-1 and 200-2 and the results of the their own simplified conversion processes, and determine the comparison results to be normal when matches are attained between the results of the simplified conversion processes.
(Sensor Element Configuration in Respective Embodiments)
The configurations of the sensor elements as used and for use in the physical quantity conversion sensors of the respective embodiments of the present invention will be described herebelow with reference to
The sensor elements 100-1 and 100-2 each use giant magnetic resistance (GMR) elements. However, magnetic resistance (MR) elements can be displaced by the GMR elements. Description herebelow refers to the GMR elements to be inclusive of the MR elements.
With reference to
With reference to
While the fixed magnetic layer is invariant in magnetization direction, the magnetization direction of a free magnetic layer follows the direction of an external magnetic field H. A resistance value of the GMR element is reliant to an angle difference a between the magnetization directions of the fixed magnetic layer and the free magnetic layer, and varies in proportion to (1−cos α).
Accordingly, a signal 101-1 proportional to Vin·sin(θ) is obtained in the first Wheatstone Bridge circuit that constitutes the sensor element 100-1. Similarly, a signal 101-2 proportional to Vin·cos(θ) (where Vin=input voltage) is obtained in the second Wheatstone Bridge circuit that constitutes the sensor element 100-2.
More specifically, the sensor elements 100-1 and 100-2, respectively, output the signal 101-1 proportional to the sine (“sin”) and the signal 101-2 proportional to the cosign (“cos”). That is, the sensor elements 100-1 and 100-2, respective, output the signals related to one another. A DC (direct current) voltage is used as the input voltage Vin that is applied to the sensor elements 100-1 and 100-2.
The sensor elements 100-1 and 100-2 are arranged in the extension direction of, for example, a rotation shaft of a rotator (a rotation shaft of a motor (
A redundantly configured physical quantity conversion sensor according to a seventh embodiment of the present invention will be described with reference to
In the present embodiment, the conversion processing section 200-1 includes a drive power generating section 206-1. The drive power generating section 206-1 outputs a drive power F(t), thereby to drive the respective sensor element 100-1, 100-2. The drive power F(t) is a cycle function, such as a sinusoidal wave voltage.
Further, the conversion processing section 200-1 includes a synchronous detector section 207-1, and the conversion processing section 200-2 includes a synchronous detector section 207-2. In accordance with the detection of the output of the respective sensor element 100-1, 100-2 by the synchronous detector section 207-1, 207-2, the respective conversion processing section 200-1, 200-2 is enabled to increase the S/N ratio. Further, with the use of the synchronous detection method, even when the drive power F(t) is set to a low current or power, a predetermined S/N ratio can still be obtained. This makes it possible to reduce migration and heat associated with the drive power F(t) in the respective sensor element 100-1, 100-2, consequently making it achieving an increase in the service life thereof.
A redundantly configurable quantity conversion sensor of an eighth embodiment of the present invention will be described with reference to
In the present embodiment, as shown in
The outputs 101-10′ and 101-2′ of the interface sections 200-3 and 200-3′ are input into a microprocessing unit, for example, as described further below (in
Although, in
Further, as shown in
A redundantly configurable quantity conversion sensor of a ninth embodiment of the present invention will be described with reference to
In the present embodiment, as shown in
In this connection, the package 70-1 includes an output terminal 101-30 to output the signal 101-3, which is proportional to the sine (“sin”) or cosign (“cos”), to the outside of the package 70-1.
Alternatively, the configuration may by such that the first and second sensor elements 100-1 and 100-2 are formed on the first package 70-1, and an area for mounting of the third sensor element 100-3 is provided in a second package.
As shown in
Since the circuit board or lead frame 71-1 is interposed, the degree of independence in probability of simultaneous faults, that is, the degree of independence in faults in the third sensor element 100-3 and the sensor elements 100-1 and 100-2 is maximized. Even in the case of lamination on the lead frame 71-1, the degree of independence in faults can be reduced.
Further, the sensor elements 100-1 and 100-2 are provided in one chip, the positional, angular misalignment between the sensor elements 100-1 and 100-2 can be minimized.
As described above, in the present embodiment, compatibility can be achieved between degree of independence in probability of simultaneous faults, i.e., faults, in the sensor elements and the positional, angular misalignment, i.e., inter-sensor element accuracy.
Further, the configuration may be formed in the manner that a space for mounting the third sensor element 100-3 and a wire-bonding space for extending the signal lines are preliminarily provided on the lead frame 71-1, and the third sensor element 100-3 is mounted only when sensor element redundancy is necessary. In this case, in the event the redundancy is not necessary, cost increases can be restrained, thereby making it possible to provide sensors at costs corresponding to required reliability.
The output terminal 101-30 for outputting the signal 101-3 proportional to the sine (“sin”) or the cosine (“cos”) can be formed into the configuration shown in, for example,
Example practical configurations of redundantly configured quantity conversion sensors of the present embodiment of the present invention will be described herebelow with reference to
To begin with, a first example practical configuration of the redundantly configured quantity conversion sensor of the present embodiment will be described herebelow with reference to
In the example practical configuration, the output terminals 101-10, 101-3 are provided. Hence, in addition to the conversion processing section 200-1 in the package 70-1, the conversion processing section 200-2 mounted in the second package 70-2 is provided, thereby to form the configuration into the redundant configuration. In the example practical configuration, the third sensor element 100-3 outputs the signal 101-3 proportional to the cosign (“cos”).
Next, a second example practical configuration of the redundantly configured quantity conversion sensor of the present embodiment will be described herebelow with reference to
In the present example practical configuration, the sensor elements 100-1 to 100-3 and conversion processing sections 200-1 and 200-2 are mounted in the common package 70-1. Further, the configuration may be formed in the manner that spaces for mounting of the third sensor element 100-3 and the conversion processing section 200-2 and a wire-bonding space for extending the signal lines are preliminarily provided on the lead frame 71-1. Then, the third sensor element 100-3 and the conversion processing section 200-2 are mounted only when the redundancy of the conversion processing section is necessary. In this case, in the event the redundancy is not necessary, cost increases can be restrained, thereby making it possible to provide sensors at costs corresponding to required reliability.
Next, an example configuration of the redundantly configurable quantity conversion sensor of the present embodiment will be described herebelow with reference to
In the present example configuration, an interface section 200-3 mounted outside of the package 70-1 is added in addition to the conversion processing section 200-1 located inside of the package 70-1. As described further below, the interface section 200-3 sends an input(s) into the microprocessing unit as described further below (in
Next, another example configuration of the redundantly configurable quantity conversion sensor of the present embodiment will be described herebelow with reference to
In the present example configuration, the interface section 200-3 and the sensor element 100-3 are mounted in a single chip, and the sensor element 100-3 is mounted in the same package as the sensor elements 100-1 and 100-2. In this case, the configuration may be formed in the manner that a space for mounting of the single chip inclusive of the interface section 200-3 and the sensor element 100-3 and a wire-bonding space for extending the signal lines inclusive of the interface section 200-3 and the sensor element 100-3 are preliminarily provided on the lead frame 71-1. Then, the single chip inclusive of the interface section 200-3 and the sensor element 100-3 are mounted only when the redundancy of the conversion processing section is necessary. In this case, in the event the redundancy is not necessary, cost increases can be restrained, thereby making it possible to provide sensors at costs corresponding to required reliability.
(Motor Control Systems in Respective Embodiments)
Next, example configurations of motor control systems using the physical quantity conversion sensors of the respective embodiments of the present invention will be described herebelow with reference to
First, a first example configuration of a motor control system using the physical quantity conversion sensor of the respective embodiment of the present invention will be described herebelow with reference to
The motor control system includes a motor section 80 and a motor controller 1. A rotor magnet 610 of the motor section 80 is attached to a rotation shaft of a motor 600. The sensor elements 100-1 and 100-2 are arranged in the extension direction of the rotation shaft of the motor 600 and in the vicinity of the rotor magnet 610.
The rotor magnet 610 supplies the respective sensor elements 100-1 and 100-2 with magnetic flux lines corresponding to the rotation angle θ of the rotation shaft of the motor 600. Corresponding to the rotation angle θ of the motor 600, the sensor elements 100-1 and 100-2, respectively, output the signal 101-1 proportional to the sine (“sin”) of the rotation angle θ and the signal 101-2 proportional to the cosign (“cos”).
The signal 101-1, which is proportional to the sine (“sin”) from the sensor element 100-1, and the signal 101-2, which is proportional to the cosign (“cos”) from the sensor element 100-2, are input into the respective conversion processing sections 200-1 and 200-2, and are converted thereby into estimated values (201-1 and φ201-2 of the rotation angle θ.
The estimated values φ201-1 and φ201-2 are input into a microprocessing unit 20 of the motor controller 1. The microprocessing unit 20 performs comparison-checking of the input estimated values φ201-1 and φ201-2 of the rotation angle θ, thereby to determine whether the estimated values φ201-1 and φ201-2 are normal. Further, in the event that the estimated values φ201-1 and φ201-2 are normal, the microprocessing unit 20 outputs a command that is implemented to generate an appropriate three-phase AC current to an inverter 30 in accordance with the estimated values φ201-1 and φ201-2. The inverter 30 outputs the three-phase AC current in accordance with the command supplied from the microprocessing unit 20, thereby to drive the motor 600.
In many cases, control to be performed in the microprocessing unit 20 is vector control. As such, in many cases, the command supplied from the microprocessing unit 20 to generate the three-phase AC current microprocessing unit 20 is a PWM (pulse width modulation) wave indicative of the respective phase.
In the event that, as a result of the comparison-checking of the input estimated values φ201-1 and φ201-2 in the microprocessing unit 20, a significant difference therebetween has been detected, any one of the estimated values φ201-1 and φ201-2 is determined to be abnormal. In this event, the microprocessing unit 20 causes outputting to the inverter 30 to stop, thereby to cause driving of the motor 600 to stop.
In regard to the implementation (or mounting) method, the method of the type shown in
Next, a second example configuration of a motor control system using the physical quantity conversion sensor of the respective embodiment of the present invention will be described herebelow with reference to
In the present example, as shown in
A command signal supplied from the microprocessing unit 20 to the inverter 30 is input into an AND gate 40 together with the diagnosis result signal 202-2 from the diagnostic function section 205-2 provided inside of the conversion processing section 200-2 and an abnormal detection signal 11 from the diagnostic function section 20-1 of the microprocessing unit 20. Then, only in the event of an H level indicative that all are normal, the inverter 30 drives the motor 600.
Further, in the event that an abnormal value has been detected, a power source relay 50 and a motor driving relay 60 are controlled in accordance with the abnormal detection signal 11 from the diagnostic function section 20-1 of the microprocessing unit 20, thereby to cause driving of the motor 600 to stop.
In this case, although not shown in the drawing, the power source relay 50 and the motor driving relay 60 may be controlled in accordance with the diagnosis result signal 202-2 that is output from the diagnostic function section 205-2. Still alternatively, the power source relay 50 and the motor driving relay 60 may be controlled in accordance with the result of AND-ing (AND-logic integration) of the abnormal detection signal 11 from the microprocessing unit 20 and the diagnosis result signal 202-2 from the diagnostic function section 205-2.
Next, a third example configuration of a motor control system using the physical quantity conversion sensor of the respective embodiment of the present invention will be described herebelow with reference to
In the present example, the configuration includes a microprocessing unit 21 in addition to the microprocessing unit 20. The microprocessing unit 21 also performs comparison-checking of the input estimated values φ201-1 and φ201-2 of the rotation angle θ, thereby to determine whether the estimated values φ201-1 and φ201-2 are normal. As a result, in the event that an abnormal value has been detected, the microprocessing unit 21 outputs the abnormal detection signal 11.
Next, example configurations of motor sections used in the motor control systems of the respective embodiments of the present invention will be described below with reference to
First, a first example configuration of the motor section of the respective embodiment of the present invention will be described herebelow with reference to
The motor 600 of the motor section 80 includes a housing 603 and a rotor 604. A stator is not shown in the drawing.
A rotation shaft 601 to which the rotor 604 is attached is attached to the housing 603 of the motor to be rotatable through a bearing 602. The rotor magnet 610 is attached to one end of the rotor 604. In the present example configuration, the rotor magnet 610 is a two-pole type having N and S poles.
A package 70 of a rotation angle sensor, which is a physical quantity conversion sensor, is provided in the extension direction of the rotation shaft 604 of the rotor magnet 610. The package 70 is mounted onto a circuit board 72. A seal 72 is provided between the rotor magnet 610 and the package 70. The provision of the seal 72 prevents that foreign matters, such as dust and oil mist, adhere or deposit onto electronic components including the package 70 mounted on the circuit board 72 to the extent of causing deterioration and/or operation failure.
Next, a second example configuration of the motor section of the respective embodiment of the present invention will be described herebelow with reference to
In the present example configuration, the rotor magnet 610 is of a four-pole type having two N poles and two S poles. In the case of the four-pole type, compared with the two-pole type, the frequency of the signal proportional to the sine (“sin”) or cosign (“cos”) is twice (cycle is half) the signal in the case of the two-pole type.
Next, a fourth example configuration of a motor control system using the physical quantity conversion sensor of the respective embodiment of the present invention will be described herebelow with reference to
A motor section 80 includes the interface section 200-3 in addition to the conversion processing section 200-1. In addition to the estimated value φ201-l of the rotation angle θ from the conversion processing section 200-1, the signal 101-1 proportional to the sine (“sin”) from the sensor element 100-1 is input as an interface-section output 101-1′ (of the interface section 200-3) into the microprocessing unit 20.
The microprocessing unit 20 estimates a value of the interface-section output 101-1′ from the input estimated value φ201-1 of the rotation angle θ. Then, the microprocessing unit 20 performs comparison-checking of the estimated value with the actually input interface-section output 101-1′, thereby to determine whether the estimated values φ201-1 of the rotation angle θ is normal.
As a result, in the event the estimated value φ201-1 is normal, the microprocessing unit 20 controls the inverter 30 to operate in accordance with the estimated value φ201-1, thereby to drive the motor 600. In the event the estimated value φ201-1 is abnormal, the microprocessing unit 20 causes outputting to the inverter 30 to stop, thereby to stop driving of the motor 600. The implementation (or mounting) methods shown in
Further, as shown by the broken line in the drawing, the configuration can include an interface section 200-3′. In this case, in addition to the estimated value of the rotation angle θ from the conversion processing section 200-1, the signal 101-1 proportional to the sine (“sin”) from the sensor element 100-1 and the signal 101-2 proportional to the cosign (“cos”) from the sensor element 100-2 are both input into the microprocessing unit 20. The respective estimated values φ201-1 and φ201-2 are thus input as interface-section outputs 101-1′ and 101-2′ through the respective interface sections 200-3 and 200-3′. The microprocessing unit 20 estimates a value of the rotation angle θ from the input interface-section outputs 101-1′ and 101-2′. Then, the microprocessing unit 20 performs comparison-checking of the estimated result with the input estimated value φ201-1, thereby to determine whether the estimated values φ201-1 of the rotation angle θ is normal. The estimation of the rotation angle θ in the microprocessing unit 20 can be implemented by performing a process similar in contents to the conversion processing in the conversion processing section 200-1.
Next, a fifth example configuration of a motor control system using the physical quantity conversion sensor of the respective embodiment of the present invention will be described herebelow with reference to
In the present example configuration, in addition to the estimated value φ201-1 of the rotation angle θ from the conversion processing section 200-1, the signal 101-1 proportional to the sine (“sin”) from the sensor element 100-1 is input into the microprocessing unit 20. The microprocessing unit 20 estimates a value of the signal 101-1 proportional to the sine (“sin”) from the input estimated value φ201-1 of the rotation angle θ. Then, the microprocessing unit 20 performs comparison-checking of the estimated value with the actually input signal 101-1 proportional to the sine (“sin”), thereby to determine whether the estimated values φ201-1 of the rotation angle θ is normal.
As a result, in the event the estimated value φ201-1 is normal, the microprocessing unit 20 controls the inverter 30 to operate in accordance with the estimated value φ201-1, thereby to drive the motor 600. In the event that the estimated value φ201-1 has been determined to be abnormal, the microprocessing unit 20 causes outputting to the inverter 30 to stop, thereby to causing driving of the motor 600 to stop. The implementation (or mounting) methods shown in
Further, as shown by the broken line, in addition to the estimated value φ201-1 of the rotation angle θ from the signal 101-1 proportional to the sine (“sin”) from the sensor element 100-1 conversion processing section 200-1, the signal 101-1 proportional to the sine (“sin”) from the sensor element 100-1 and the signal 101-2 proportional to the cosign (“cos”) from the sensor element 100-2 may be input into the microprocessing unit 20. In this case, the microprocessing unit 20 estimates the rotation angle θ from the signal 101-1 proportional to the sine (“sin”) and signal 101-2 proportional to the cosign (“cos”). Then, the microprocessing unit 20 performs comparison-checking of the estimated result with the input estimated value φ201-1 of the rotation angle θ, thereby to determine whether the estimated values φ201-1 of the rotation angle θ is normal.
Also in each of the embodiment examples shown in
Next, an electric power steering system, which is a first practical example of the motor control system of the respective embodiment of the present invention, will be described herebelow with reference to
In the present practical example, in addition to the motor controller 1 and the motor section 80, which are provided in the example configuration of the motor control system shown in
The microprocessing unit 20 of the motor controller 1 controls the motor 600 so that the motor 600 outputs an assist torque corresponding to an operation force of a driver or vehicle operator detected by a torque sensor 3.
In the electric power steering system shown in
Next, an electronically-controlled throttle system, a second practical example of the motor control system of the respective embodiment of the present invention, will be described herebelow with reference to
In the present practical example, as shown in
The amount of operation of the accelerator pedal 5 by the driver is input as redundant outputs φ201-1′ and φ201-2 into the microprocessing unit 20. Similarly, the travel or opening (position) of the throttle valve 310 is input as redundant outputs φ201-1 and 201-2 into the microprocessing unit 20.
The microprocessing unit 20 controls the opening of the throttle valve 310 in accordance with the redundant outputs φ201-1′ and φ201-2′. The opening of the throttle valve 310 is input as redundant outputs φ201-1 and φ201-2 into the microprocessing unit 20. The microprocessing unit 20 performs control so that the difference from the redundant outputs φ201-1′ and φ201-2′, which are each a target value becomes zero.
The power of the motor 600 is transmitted to a throttle valve shaft 40 via a gear mechanism 303 (including a pinion 303A, intermediate gear 303B, and final gear 303C) thereby to drive the throttle valve 310.
Further, in the event that a mismatching or contradictory relationship occurs between the redundant outputs φ201-1 and φ201-2′ of the accelerator position sensor and the redundant outputs φ201-1 and φ201-2 of the throttle position sensor, the accelerator position sensor and/or the throttle position sensor is abnormal. Hence, devices (means) shown in, for example,
Next, an example configuration of an electronically-controlled throttle device will be described herebelow with reference to
A gear cover 314 of the gear mechanism 303 for motor power transmission is attached to a throttle body 300 that includes the throttle valve 310. A throttle position sensor (throttle valve rotation angle detection device) is attached to the gear cover 314. The gear cover 314 is made of a synthetic resin, and is integrally formed with a connector 313 that includes an external connection terminal that is used for electrical connection between an external device and a power supply. In the throttle body 300, a motor housing 301 for housing the motor 600 that drives the throttle valve shaft 40, and a gear housing 306 in which the gear mechanism 303 and the default mechanism are arranged, are integrally formed. The gear cover 314 covers the gear housing 306. A sensor housing is formed in the gear cover 314.
Power supply terminals of motor 600 (302A and 302B in a brushed motor/302A, 302B, and 302C in a brushless motor) are connected to intermediate terminals 312A and 312B provided to the gear cover 314 via a connection metal furniture 311. The power of the motor 600 is transmitted to the throttle valve shaft 40 via the gear mechanism 303 (pinion 303A, intermediate gear 303B, and final gear 303C) thereby to drive the throttle valve 310. The rotor magnet 610 is attached to one end 41 of the throttle valve shaft 40. A return force is exerted by a return spring 305 on the throttle valve shaft 40.
Next, another example configuration of an electronically-controlled throttle system, which is a second practical example of the motor control system of the respective embodiment of the present invention, will be described herebelow with reference to
In the present configuration example, the power of the motor 600 is transmitted to the throttle valve shaft 40 without being passed through the gear mechanism, thereby to drive the throttle valve 310.
As described above, according to the respective embodiment of the present invention, the output terminals for outputting the signals proportional to the sine (“sin”) and cosign (“cos”) from the sensor elements to the outside of the package. Thereby, the conversion processing sections can be redundantly provided on the outside of the package by necessity, and hence the fault detection for the conversion processing sections can be implemented, and costs can be optimized.
Further, in the case where the conversion processing sections redundantly provided on the outside of the package are implemented with software to be operable in a microcomputer, a necessary minimum redundant configuration can be realized without additional hardware being required. This leads to cost reduction.
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2007-224447 | Aug 2007 | JP | national |
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