This application claims the priority benefit of Taiwan application serial no. 107120338, filed on Jun. 13, 2018. The entirety of the above-mentioned patent application is hereby incorporated by reference herein and made a part of this specification.
The invention relates to an alternator apparatus and a voltage converter, particularly related to an alternator apparatus and a voltage converter which can execute electric energy recovery and energy flywheel.
In vehicle devices, power generators for vehicles are usually composed of rotors, stators, bridge rectifiers, regulators, and pulleys. According to the working principle of a power generator, an excitation is executed in the rotor, such that the rotor generates a magnetic field, and rotates according to energy provided by an engine. Through the rotation of the rotor, the magnetic field of the rotor cuts a stator coil. In addition, by cutting effect of the magnetic field, the stator generates AC power correspondingly, and the generated AC power is rectified to DC power after a full wave rectification. The generated power is transferred to a battery and an electrical load of a vehicle.
To correspond to the present electronic applications of vehicles, alternator apparatus of vehicle devices may generate a plurality of powers (e.g. dual power) by using voltage converters. Furthermore, when load dumping of the alternator apparatus occurs, the alternator apparatus generates unstable bounce owing to rapid changes of load state. Improving the efficiency of power usage of the alternator apparatus, and reducing the impact caused by load dumping are important issues for people skilled in the art.
The invention provides an alternator apparatus and a voltage converter, which can execute an electric energy recovery during a reset time period.
The voltage converter of one exemplary embodiment of the invention includes a voltage converting circuit and an auxiliary circuit. The voltage converting circuit comprises a first power end, a second power end and an inductor. The voltage converting circuit, during an operation time period, converts a first voltage on the first power end so as to generate a second voltage on the second power end, or the voltage converting circuit, during the operation time period, converts the second voltage on the second power end so as to generate the first voltage on the first power end, wherein a voltage value of the first voltage is larger than a voltage value of the second voltage. The auxiliary circuit is coupled between the first power end and the second power end. The auxiliary circuit, during the reset time period, forms a first loop between the first power end and the inductor, or forms a second loop between the second power end and the inductor, or forms a third loop in the auxiliary circuit. The first loop and the second loop execute electric energy recovery, and the third loop executes energy flywheel.
The alternator apparatus of one exemplary embodiment of the invention includes a power generator and the aforementioned voltage converter. The power generator has a rotor and a stator, where the stator generates an output voltage. The power generator transmits the output voltage to the first power end or the second power end of the voltage converter as the first power or the second power.
In view of the above, the voltage converter of one exemplary embodiment of the invention, during the operation time period, provides different modes of voltage converting operation. In addition, during the reset time period, a circuit loop is formed between a reference ground end and the first power end or the second power end to execute energy recovery or energy flywheel. As such, when the load dumping of the alternator apparatus occurs, the value of the output voltage will become stable rapidly, and the probability of having negative effects on the system will be reduced.
To provide a further understanding of the aforementioned and other features and advantages of the disclosure, exemplary embodiments, together with the reference drawings, are described in detail below.
On the other hand, when a load dumping occurs, the voltage converting circuit 110 operates during a reset time period in the boost mode. At this time, the voltage converting circuit 110 stops executing the voltage converting operation. Correspondingly, a loop is formed through the auxiliary circuit 120, which is between the second power end E2 as the input end and a reference ground, and thus during the reset time period, the energy stored on the voltage converting circuit 110 could be recovered to the input end (i.e. the second power end E2) or be stored by executing flywheel energy storage for extra energy, so as to rapidly reduce voltage fluctuation situation of the voltage V1 and the voltage V2. The flywheel energy storage mentioned in the embodiment is by continuing the energy flow in a current loop. As such, the electric energy may be effectively stored in a current loop, and may not be wasted. Moreover, when the voltage converter 100 restarts to operate, a normal operating state may be rapidly resumed.
Besides, when the voltage converting circuit 110 operates during the operation time period in the buck mode, the first power end E1 of the voltage converting circuit 110 is used as an input end. The voltage converting circuit 110 receives the voltage V1 by the first power end E1, and the voltage converting operation in the buck mode is executed according to the voltage V1, so as to generate the voltage V2 on the second power end E2.
On the other hand, when, for example, the load dumping occurs, the voltage converting circuit 110 operates during the reset time period in the buck mode. At this time, the voltage converting circuit 110 stops executing the voltage converting operation. Correspondingly, a loop is formed through the auxiliary circuit 120, which is between the first power end E1 (used as the input end) and the reference ground end, and thus during the reset time period, the energy stored on the voltage converting circuit 110 could be recovered to the input end (the first power end E1), or flywheel energy storage could be executed in the auxiliary circuit 120, so as to rapidly reduce voltage fluctuation situation of the voltage V1 and the voltage V2.
Based on the aforementioned illustrations, it is acquired that, when the voltage (the voltage V1 or V2) state occurs abnormal changes (for example, having the load dumping), by the loop formed through the auxiliary circuit 120 during the reset time period, the energy stored in the voltage converting circuit 110 may be effectively recovered to the input end or be stored by executing the flywheel energy storage in the auxiliary circuit 120. The voltage instability caused by the load dumping may be rapidly reduced. Apart from effectively applying energy, the voltage generated by the voltage converting circuit 110 may become stable rapidly, so as to enhance the stability of the system operation.
The voltage converting circuit 210 has the first power end E1 and the second power end E2. The voltage converting circuit 210 includes switches SW1 and SW2 and an inductor L1. The switches SW1 and SW2 are constructed by transistors. Regarding an operation method of the voltage converting circuit 210, during the operation time period in the boost mode, the switches SW1 and SW2 are interactively turned on and turned off, and a boost operation is executed according to the voltage V2. When the switch SW2 is turned on (while the switch SW1 is turned off), a loop is formed through the second power end E2, the inductor L1 and the switch SW2, such that the inductor L1 stores energy. Then, when the switch SW1 is turned on (while the switch SW2 is turned off), the energy in the inductor L1 is provided to the first power end E1 through the switch SW1, and the voltage V1 is generated.
During the operation time period in the buck mode, the switches SW1 and SW2 are interactively turned on and turned off, a buck operation is executed according to the voltage V1, and the voltage V2 is generated on the second power end E2. When the switch SW1 is turned on (while the switch SW2 is turned off), a loop is formed through the first power end E1, the switch SW1, and the inductor L1, such that the inductor L1 stores energy according to the voltage V1. Then, when the switch SW2 is turned on (while the switch SW1 is turned off), a first end of the inductor L1 is coupled to a reference ground end GND through the switch SW2, and the buck operation is executed to generate the voltage V2.
In this embodiment, the auxiliary circuit 220 includes switches SW3 and SW4 and an auxiliary inductor LA1. The switch SW3 is coupled between the first power end E1 and a first end of the auxiliary inductor LA1, and is controlled by a control signal CTA1, so as to be turned on or turned off. The switch SW4 is serially connected between the first end of the auxiliary inductor LA1 and the reference ground end GND, and is controlled by a control signal CTA2 so as to be turned on or turned off. A second end of the auxiliary inductor LA1 is coupled to the second power end E2.
During the operation time period, the operation manners of the auxiliary circuit 220 and the voltage converting circuit 210 are similar. For example, when the voltage converting circuit 210 executes a voltage converting operation of buck and generates the voltage V2, the auxiliary circuit 220 provides transient energy flow, so as to generate an auxiliary voltage VA2 on the second power end E2 according to the voltage V1. Similarly, when the voltage converting circuit 210 executes a voltage converting operation of boost and generates the voltage V1, the auxiliary circuit 220 also provides transient energy flow, so as to generate the auxiliary voltage VA1 on the first power end E1 according to the voltage V2. It should be noted that, an operating bandwidth of the auxiliary circuit 220 is larger than an operating bandwidth of the voltage converting circuit 210.
Specifically, when the voltage converting circuit 210 and the auxiliary circuit 220 executes a voltage converting operation of buck at the same time, a switching frequency of the switch SW3 is higher than a switching frequency of the switch SW1, such that the operating bandwidth of the auxiliary circuit 220 is larger than the operating bandwidth of the voltage converting circuit 210. On the other hand, when the voltage converting circuit 210 and the auxiliary circuit 220 execute the voltage converting operation of boost at the same time, a switching frequency of the switch SW3 and a switching frequency of the switch SW4 are higher than the switching frequencies of the switches SW1 and SW2, such that the operating bandwidth of the auxiliary circuit 220 is larger than the operating bandwidth of the voltage converting circuit 210.
On the other hand, please refer to
On the other hand, during the reset time period in the boost mode, the switch SW1 in the voltage converting circuit 210 and the switch SW3 in the auxiliary circuit 220 are constantly in the turn-on state, whereas the switch SW2 in the voltage converting circuit 210 and the switch SW4 in the auxiliary circuit 220 are constantly in the turn-off state. As such, a loop LP3 is formed in the auxiliary circuit 220. Through the loop LP3, during the reset time period in the boost mode, the energy flywheel operation is executed in the auxiliary circuit 220.
It should be noted that, in the voltage converter 200 of the embodiment, during the operation time period, the auxiliary voltage VA1 or VA2 is provided by the auxiliary circuit 210 to effectively enhance efficiency. In addition, during the reset time period, by providing energy recovering or by energy flywheel, extent of voltage overshoot or undershoot of the generated voltage V1 or V2 may be effectively reduced to maintain the system stability.
While entering the reset time period, the switches SW3 and SW4 are turned on. The loop LP3 is formed through the switches SW3 and SW4 and the inductor L1 to execute energy flywheel operation, where an energy transmission direction of the loop LP3 is related to whether the voltage converter 300 operates in the boost mode or in the buck mode. When the voltage converter 300 operates in the buck mode, the energy transmission direction of the loop LP3 is in counterclockwise direction. Contrarily, when the voltage converter 300 operates in the boost mode, the energy transmission direction of the loop LP3 is in clockwise direction.
In this embodiment, the transistors M1 and M2 are coupled in the back-to-back manner. Resistance value provided when the transistors M1 and M2 are turned on is lowered, so as to improve the performance of energy flywheel.
With the aforementioned energy recovery or energy flywheel mechanism, when the voltage V1 or V2 generated by the voltage converter 300 occurs abnormal changes, such as overshoot or undershoot, the voltage variation may be reduced thereby, and a steady state may be quickly returned.
It should be noted that, in the voltage converter 300 of the embodiment, through energy flywheel operation during the reset time period, the extent of voltage overshoot of the generated voltage V1 or V2 may be effectively reduced. In addition, it is not necessary for the loop LP3 generated by the voltage converter 300 to operate with a battery element as an auxiliary mechanism for energy recovery, and the variation degree of the voltage V1 or V2 is effectively stable. Besides, the auxiliary circuit 320 of this embodiment merely requires simple circuit architecture. Therefore, the design also has its advantages on design cost.
In this embodiment, a capacitor C1 is coupled between the first power end E1 and the reference ground end GND, and a capacitor C2 is coupled between the second power end E2 and the reference ground end GND, where the capacitors C1 and C2 may be used as voltage regulating (energy storing) capacitors.
On the other hand, the auxiliary circuit 420 includes switches SW3 and SW4, and diodes D1, D2 and D3. The auxiliary circuit 420 and the voltage converting circuit 410 share some elements such as the diode D1 and the switch SW3. The diode D1 is coupled between the second end of the inductor L1 and the reference ground end GND, where the anode of the diode D1 is coupled to the reference ground end GND, and the cathode of the diode D1 is coupled to the second end of the inductor L1. Besides, the switch SW3 is coupled between the second end of the inductor L1 and the second power end E2. The switch SW3 also receives the control signal CT3, so as to be turned on or turned off according to the control signal CT3. The diode D2 is coupled between the first power end E1 and the second end of the inductor L1. The diode D3 is coupled between the second power end E2 and the switch SW4. The switch SW4 is further coupled to the first end of the inductor L1, receiving and being controlled by a control signal CT4 so as to be turned on or turned off, where the anode of the diode D2 is coupled to the second end of the inductor L1, and the cathode of the diode D2 is coupled between the first power end E1. The anode of the diode D3 is coupled to the first end of the inductor L1. The cathode of the diode D3 is coupled to the second power end E2.
Regarding the operation method of a voltage converter 400, please refer to
On the other hand, in the auxiliary circuit 420, the switch SW3 is constantly in a turn-on state, and the switch SW4 is constantly in a turn-off state.
In
In
On the other hand, in the auxiliary circuit 420, the switch SW3 is constantly in the turn-on state, and the switch SW4 is constantly in the turn-off state.
In
It should also be mentioned that, in the aforementioned embodiments, the switches SW1-SW4 may be constructed by transistors or any other kind of semiconductor devices or components. The diodes D1-D3 may be constructed by transistors coupled as diode configuration, P-N junction diode, or any other forms that are familiar to people skilled in the art, which is not limited thereto.
The generation methods of the control signals CT1-CT4 may be generated by disposing a control signal (not illustrated). The control signal generator may be constructed by a pulse width modulation (PWM) signal generator according to the conventional voltage converter technical field, which is not limited thereto.
On the other hand, through a simple control mechanism, the voltage converter 400 of this embodiment, may effectively execute energy recovery operation, effectively enhance the stability of the voltages V1 and V2, and maintain system efficiency.
The alternator apparatus 600 provides different voltage values of the voltage V1 and V2 so as to generate dual power to drive loads, which require different power consumption in the driving system, so as to enhance power efficiency. Furthermore, the voltage converter 620 may be implemented according to the aforementioned voltage converters 100, 200, 300 or 400, such that when the voltages V1 and V2 occur voltage changes, the output voltage generated by the alternator apparatus 600 is stable. Moreover, through the energy recovery mechanism or the energy flywheel during the reset time period, the power efficiency is improved.
The voltage converter 712 may be implemented according to the aforementioned embodiments of the voltage converters 100, 200, 300 or 400. Regarding operating details of the voltage converter 712, the detailed illustrations are elaborated in the aforementioned embodiments, which shall not be repeated.
In
The voltage converter 722 may be implemented according to the aforementioned embodiments of the voltage converters 100, 200, 300, or 400. Regarding operating details of the voltage converter 722, the detailed illustrations thereof are elaborated in the aforementioned embodiments, which shall not be repeated.
In summary of the above, the voltage converter having energy recovering ability is disposed in the alternator apparatus of the invention. When the load dumping occurs, the voltage concussion generated by, for example, load instantaneous changes, may be effectively controlled through the energy recovering mechanism of the voltage converter or the energy flywheel mechanism, such that the output voltage generated by the alternator apparatus is stably enhanced, and the system effective operation is maintained.
Although the invention is disclosed as the embodiments above, the embodiments are not meant to limit the invention. Any person skilled in the art may make slight modifications and variations without departing from the spirit and scope of the invention. Therefore, the protection scope of the invention shall be defined by the claims attached below.
Number | Date | Country | Kind |
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107120338 | Jun 2018 | TW | national |