This disclosure is directed to an ultracapacitor module with dead band bus voltage control system.
Typically, an ultracapacitor module connected to a voltage supply bus has no ability to control the current sourced from or provided to the ultracapacitor. An example of this may be found in an ultracapacitor module in a voltage stabilization system that increases the voltage of the voltage supply bus of a vehicle while the starter system of an internal combustion engine is engaged and includes a parallel DC/DC converter to recharge the capacitors in the ultracapacitor module. Another example is a backup power supply module which increases the voltage of the voltage supply bus of a vehicle when the bus voltage sags. This module also includes a parallel DC/DC converter to recharge the capacitors in the ultracapacitor module. These examples have no need for adaptive voltage control because they have no method of controlling a response of the ultracapacitor module to voltage transients on the voltage supply bus. In these examples, the capacitor voltage and the working range of the voltage supply bus are the same. There is no control of the bus voltage other than the natural control provided by the capacitor(s).
In some aspects, the techniques described herein relate to an ultracapacitor module, including: an ultracapacitor cell stack containing one or more ultracapacitor cells; a bidirectional boost/buck DC/DC converter, wherein the ultracapacitor cell stack and the DC/DC converter are configured to be connected in series with a voltage supply bus of a vehicle; one or more voltage sensors configured to determine an operating voltage Vo of the voltage supply bus; and an electronic controller in electrical communication with the DC/DC converter and the one or more voltage sensors, wherein the electronic controller is configured to: control the DC/DC converter using a first set of control parameters when the operating voltage Vo is greater than a target bus voltage value Vt, and control the DC/DC converter using a second set of control parameters different from the first set of control parameters when the operating voltage Vo is less than the target bus voltage value Vt.
In some aspects, the techniques described herein relate to a method of operating an ultracapacitor module connected to a voltage bus of a vehicle, the ultracapacitor module having an ultracapacitor cell stack containing one or more ultracapacitor cells, a bidirectional boost/buck DC/DC converter, wherein the ultracapacitor cell stack and the DC/DC converter are connected in series with the voltage bus, one or more voltage sensors configured to determine an operating voltage Vo of the voltage bus, and an electronic controller in electrical communication with the DC/DC converter and the one or more voltage sensors, the method including: controlling the DC/DC converter using a first set of control parameters when the operating voltage Vo is greater than a target bus voltage value Vt; and controlling the DC/DC converter using a second set of control parameters different from the first set of control parameters when the operating voltage Vo is less than the target bus voltage value Vt.
In some aspects, the techniques described herein relate to a computer readable medium containing program instructions for operating an ultracapacitor module connected to a voltage bus of a vehicle, the ultracapacitor module having an ultracapacitor cell stack containing one or more ultracapacitor cells, a bidirectional boost/buck DC/DC converter, wherein the ultracapacitor cell stack and the DC/DC converter are connected in series with the voltage bus, one or more voltage sensors configured to determine an operating voltage Vo of the voltage bus, and an electronic controller in electrical communication with the DC/DC converter and the one or more voltage sensors, wherein execution of the program instructions by one or more processors of a computer system causes the electronic controller to carry out: controlling the DC/DC converter using a first set of control parameters when an operating voltage Vo is greater than a target bus voltage value Vt; and controlling the DC/DC converter using a second set of control parameters different from the first set of control parameters when the operating voltage Vo is less than the target bus voltage value Vt.
The ultracapacitor module will now be described, by way of example with reference to the accompanying drawings, in which:
The present disclosure describes an ultracapacitor module shown in
As shown in
The UCM 100 further includes a bidirectional boost/buck DC/DC converter 208 that is capable of conducting at least the same current as the ultracapacitor cell stack 202 as the current flows in to or out of the ultracapacitor cell stack 202. Under the control of the electronic controller 206, the DC/DC converter 208 quickly switches between boost and buck modes. The time period for this transition is preferably in the order of 25 to 100 microseconds. Other electronic modules connected to the voltage supply bus 218 may also include capacitors that are appropriately sized to provide electrical power to these electronic modules during voltage transients on the voltage supply bus 218 while the DC/DC converter 208 is transitioning between boost and buck modes. The electronic controller 206 also controls the direction and the magnitude of electrical power flowing through the DC/DC converter 208. The electronic controller 206 additionally monitors the voltage of the voltage supply bus 218 and adaptively determines its nominal value, its rate of change, and, optionally, its frequency spectrum content. The UCM 100 may optionally include a switch 210 to protect against reverse polarity voltage.
In some embodiments, UCM 100 includes a plurality of ultracapacitor cells 204 connected in series with one another to form an ultracapacitor cell stack 202, a DC/DC converter 208, a switch 210 and an electronic controller 206. As shown in
As shown in
As shown in
As further shown in
As shown in
The operating voltage Vo has a relatively large variance range due to temperature, operational tolerances of other components, vehicle-to-vehicle variance, ultracapacitor module life stage, and electrical noise on the voltage supply bus 218. Dual dead bands shown in the electronic controller 206 in
The UCM 100 mitigates several types of voltage fluctuations or transients on the voltage supply bus 218 as shown in
To control the two different voltage disturbances on the voltage supply bus 218, the electronic controller 206 has two individual control loops with different gain characteristics for voltage sags and voltage spikes. Each control loop has a dead band so that the DC/DC converter 208 avoids transitioning from boost mode to buck mode during the same transient.
An upper or positive dead band 302, shown in
To control different types of voltage disturbances (e.g., sags, spikes) on the voltage supply bus 218, the electronic controller 206 has two individual control loops with different gain characteristics. Each control loop has a dead band so that the DC/DC converter 208 avoids transitioning from boost mode to buck mode during the same transient. An upper dead band 302, shown in
Additionally, the electronic controller 206 may measure the direction and frequency content of disturbances on the voltage supply bus 218 and use this information to modify the dead bands. Some examples of this feature are shown in
In some embodiments, the target bus voltage value Vt, the upper dead band limit and the lower dead band limit may be set by an external module over a LIN/CAN communication bus so that the UCM 100 operates in a primary/secondary relationship with a vehicle DC/DC converter (not shown). In other embodiments, the target bus voltage value Vt, the upper dead band limit and the lower dead band limit may be set to the same value by an external module over a LIN/CAN communication bus to provide filtering of a sinusoidal noise voltage on the voltage supply bus 218, e.g., caused by an alternator.
The upper voltage limit is set to protect the ultracapacitor cell stack 202 from absorbing excess voltage from the voltage supply bus 218 that would damage the ultracapacitor cell stack 202. The lower voltage limit is set at a level below which the ultracapacitor cell stack 202 is not able to supply enough power to the DC/DC converter 208 to raise the voltage on the voltage supply bus 218. The programmable float voltage value Vf is set between the upper and lower voltage limits and can be controlled by the electronic controller 206. The float voltage value Vf can be shifted down to increase charging headroom between the float voltage value Vf and the upper voltage limit, which decreases the discharging headroom between the float voltage value Vf and the lower voltage limit. Alternatively, the float voltage value Vf can be shifted up to increase discharging headroom between the float voltage value Vf and the lower voltage limit, which decreases the charging headroom between the float voltage value Vf and the upper voltage limit. The ultracapacitor cell stack 202 is charged to absorb excess voltage on the voltage supply bus 218 and the ultracapacitor cell stack 202 is discharged to provide electrical power to raise the voltage on the voltage supply bus 218.
In some embodiments, the electronic controller 206 disables the DC/DC converter 208 when the operating voltage Vo is within a predetermined dead band voltage range greater than and/or below the target bus voltage value Vt. In this state the switching of the DC/DC converter 208 may be stopped to minimize power consumption, reduce electrical noise, and ensure that no current is flowing into or out of the ultracapacitor cell stack 202.
In some aspects, the techniques described herein relate to an ultracapacitor module, including: an ultracapacitor cell stack containing one or more ultracapacitor cells; a bidirectional boost/buck DC/DC converter, wherein the ultracapacitor cell stack and the DC/DC converter are configured to be connected in series with a voltage supply bus of a vehicle; one or more voltage sensors configured to determine an operating voltage Vo of the voltage supply bus; and an electronic controller in electrical communication with the DC/DC converter and the one or more voltage sensors, wherein the electronic controller is configured to: control the DC/DC converter using a first set of control parameters when the operating voltage Vo is greater than a target bus voltage value Vt, and control the DC/DC converter using a second set of control parameters different from the first set of control parameters when the operating voltage Vo is less than the target bus voltage value Vt.
In some aspects, the techniques described herein relate to an ultracapacitor module, wherein electronic controller is further configured to control the DC/DC converter using the first set of control parameters when the operating voltage Vo is at or greater than an upper dead band limit of an upper dead band voltage range, and control the DC/DC converter using the second set of control parameters when the operating voltage Vo is at or below a lower dead band limit of a lower dead band voltage range.
In some aspects, the techniques described herein relate to an ultracapacitor module, wherein the electronic controller is further configured to disable the DC/DC converter when the operating voltage Vo is within an upper dead band voltage range greater than the target bus voltage value Vt.
In some aspects, the techniques described herein relate to an ultracapacitor module, wherein the electronic controller is further configured to disable the DC/DC converter when the operating voltage Vo is within a lower dead band voltage range below the target bus voltage value Vt.
In some aspects, the techniques described herein relate to an ultracapacitor module, wherein a magnitude of the upper dead band voltage range is different than a magnitude of the lower dead band voltage range.
In some aspects, the techniques described herein relate to an ultracapacitor module, wherein the lower dead band voltage range is determined by the electronic controller based on transitions of the operating voltage Vo relative to the target bus voltage value Vt.
In some aspects, the techniques described herein relate to an ultracapacitor module, wherein the lower dead band voltage range is further determined by the electronic controller based on frequency content of the transitions of the operating voltage Vo relative to the target bus voltage value Vt.
In some aspects, the techniques described herein relate to an ultracapacitor module, wherein the upper dead band voltage range is determined by the electronic controller based on transitions of the operating voltage Vo relative to the target bus voltage value Vt.
In some aspects, the techniques described herein relate to an ultracapacitor module, wherein the upper dead band voltage range is further determined by the electronic controller based on frequency content of the transitions of the operating voltage Vo relative to the target bus voltage value Vt.
In some aspects, the techniques described herein relate to a method of operating an ultracapacitor module connected to a voltage bus of a vehicle, the ultracapacitor module having an ultracapacitor cell stack containing one or more ultracapacitor cells, a bidirectional boost/buck DC/DC converter, wherein the ultracapacitor cell stack and the DC/DC converter are connected in series with the voltage bus, one or more voltage sensors configured to determine an operating voltage Vo of the voltage bus, and an electronic controller in electrical communication with the DC/DC converter and the one or more voltage sensors, the method including: controlling the DC/DC converter using a first set of control parameters when the operating voltage Vo is greater than a target bus voltage value Vt; and controlling the DC/DC converter using a second set of control parameters different from the first set of control parameters when the operating voltage Vo is less than the target bus voltage value Vt.
In some aspects, the techniques described herein relate to a method, wherein the method further includes controlling the DC/DC converter using the first set of control parameters when the operating voltage Vo is at or greater than an upper dead band limit of an upper dead band voltage range, and controlling the DC/DC converter using the second set of control parameters when the operating voltage Vo is at or below a lower dead band limit of a lower dead band voltage range.
In some aspects, the techniques described herein relate to a method, wherein the method further includes disabling the DC/DC converter when the operating voltage Vo is within an upper dead band voltage range greater than the target bus voltage value Vt.
In some aspects, the techniques described herein relate to a method, wherein the method further includes disabling the DC/DC converter when the operating voltage Vo is within a lower dead band voltage range below the target bus voltage value Vt.
In some aspects, the techniques described herein relate to a method, wherein a magnitude of the upper dead band voltage range is different than a magnitude of the lower dead band voltage range.
In some aspects, the techniques described herein relate to a method, wherein the lower dead band voltage range is determined by the electronic controller based on transitions of the operating voltage Vo relative to the target bus voltage value Vt.
In some aspects, the techniques described herein relate to a method, wherein the lower dead band voltage range is further determined by the electronic controller based on frequency content of the transitions of the operating voltage Vo relative to the target bus voltage value Vt.
In some aspects, the techniques described herein relate to a method, wherein the upper dead band voltage range is determined by the electronic controller based on transitions of the operating voltage Vo relative to the target bus voltage value Vt.
In some aspects, the techniques described herein relate to a method, wherein the upper dead band voltage range is further determined by the electronic controller based on frequency content of the transitions of the operating voltage Vo relative to the target bus voltage value Vt.
In some aspects, the techniques described herein relate to a computer readable medium containing program instructions for operating an ultracapacitor module connected to a voltage bus of a vehicle, the ultracapacitor module having an ultracapacitor cell stack containing one or more ultracapacitor cells, a bidirectional boost/buck DC/DC converter, wherein the ultracapacitor cell stack and the DC/DC converter are connected in series with the voltage bus, one or more voltage sensors configured to determine an operating voltage Vo of the voltage bus, and an electronic controller in electrical communication with the DC/DC converter and the one or more voltage sensors, wherein execution of the program instructions by one or more processors of a computer system causes the electronic controller to carry out: controlling the DC/DC converter using a first set of control parameters when an operating voltage Vo is greater than a target bus voltage value Vt; and controlling the DC/DC converter using a second set of control parameters different from the first set of control parameters when the operating voltage Vo is less than the target bus voltage value Vt.
In some aspects, the techniques described herein relate to a computer readable medium, wherein execution of the program instructions by one or more processors of a computer system further causes the electronic controller to control the DC/DC converter using the first set of control parameters when the operating voltage Vo is at or greater than an upper dead band limit of an upper dead band voltage range, and control the DC/DC converter using the second set of control parameters when the operating voltage Vo is at or below a lower dead band limit of a lower dead band voltage range.
While the invention has been described with reference to an exemplary embodiment(s), it will be understood by those skilled in the art that various changes may be made, and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention is not limited to the disclosed embodiment(s), but that the invention will include all embodiments falling within the scope of the appended claims.
As used herein, ‘one or more’ includes a function being performed by one element, a function being performed by more than one element, e.g., in a distributed fashion, several functions being performed by one element, several functions being performed by several elements, or any combination of the above.
It will also be understood that, although the terms first, second, etc. are, in some instances, used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, a first contact could be termed a second contact, and, similarly, a second contact could be termed a first contact, without departing from the scope of the various described embodiments. The first contact and the second contact are both contacts, but they are not the same contact.
The terminology used in the description of the various described embodiments herein is for the purpose of describing particular embodiments only and is not intended to be limiting. As used in the description of the various described embodiments and the appended claims, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will also be understood that the term “and/or” as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items. It will be further understood that the terms “includes,” “including,” “comprises,” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.
As used herein, the term “if” is, optionally, construed to mean “when” or “upon” or “in response to determining” or “in response to detecting,” depending on the context. Similarly, the phrase “if it is determined” or “if [a stated condition or event] is detected” is, optionally, construed to mean “upon determining” or “in response to determining” or “upon detecting [the stated condition or event]” or “in response to detecting [the stated condition or event],” depending on the context.
Additionally, while terms of ordinance or orientation may be used herein these elements should not be limited by these terms. All terms of ordinance or orientation, unless stated otherwise, are used for purposes distinguishing one element from another, and do not denote any particular order, order of operations, direction or orientation unless stated otherwise.
This application claims the benefit of and priority to U.S. Provisional Application 63/427,179, titled “Ultracapacitor Module with Dead Band Voltage Control System”, filed Nov. 22, 2022, and further claims the benefit of and priority to U.S. Provisional Application 63/462,332, titled “Ultracapacitor Module with Dead Band Voltage Control System”, filed Apr. 27, 2023, the contents of each of which are incorporated by reference herein.
Number | Date | Country | |
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63427179 | Nov 2022 | US | |
63462332 | Apr 2023 | US |