KR102619724B1 - Battery pack, and dc/dc conveter control method of battery management system - Google Patents

Abstract

A DC/DC converter control method of a battery management system installed in a vehicle equipped with a first battery for motor driving, a second battery for electric load, and a DC/DC converter connected between the first and second batteries, the vehicle Upon entering the regenerative braking mode, controlling the output voltage of the DC/DC converter to a first voltage. When the end of the regenerative braking mode is requested, the DC/DC converter is controlled according to whether the first battery is fully charged. It may include changing the output voltage change rate, and reducing the output voltage of the DC/DC converter to a second voltage based on the output voltage change rate.

Description

Battery pack, and DC/DC converter control method of the battery management system {BATTERY PACK, AND DC/DC CONVETER CONTROL METHOD OF BATTERY MANAGEMENT SYSTEM}

Embodiments of the present invention relate to a battery pack and a DC/DC converter control method of a battery management system.

Recently, as environmental regulations such as CO2 regulations have been strengthened, interest in eco-friendly vehicles is increasing. Accordingly, automobile companies are actively conducting research and product development on not only hybrid vehicles or plug-in hybrid vehicles, but also pure electric vehicles or hydrogen vehicles.

Eco-friendly vehicles are equipped with an electric drive motor, a main battery for driving the motor, an auxiliary battery for electric loads, and a converter to charge the auxiliary battery from the main battery. In eco-friendly vehicles, the drive motor is driven by electrical energy stored in the battery to provide driving force for the vehicle, and in situations where vehicle deceleration is necessary, it rotates in the opposite direction to the vehicle's driving direction to decelerate the vehicle and generates counter electromotive force to protect the battery. It also recharges. In this way, charging the battery while decelerating the vehicle using the drive motor is called regenerative braking.

In eco-friendly vehicles, a DC/DC converter is installed between the high-voltage main battery and the low-voltage auxiliary battery. This DC/DC converter receives a required output voltage command from the vehicle controller (Hybrid Control Unit, or Vehicle Control Unit), and based on this, converts the high voltage output of the main battery into the required voltage to charge the auxiliary battery. Typically, the vehicle controller increases the output voltage of the DC/DC converter in the main battery charging mode to store as much energy as possible in the auxiliary battery, and in the main battery discharging mode, the DC/DC converter is used to minimize power consumption of the main battery. Lowers the output voltage of the DC converter. Therefore, while the vehicle is driving in regenerative braking mode, the output voltage of the DC/DC converter increases, and when regenerative braking ends, the output voltage of the DC/DC converter decreases.

If energy regeneration is maintained for a long time in situations where there is a lot of coasting or braking, such as a long downhill section, a situation may occur where the main battery is fully charged. When the main battery is fully charged, regenerative braking must end and the mode must be switched to friction braking using a brake disc pad. The section where regenerative braking is converted to friction braking is called the torque blending section. In this torque blending section, the sum of the torque caused by regenerative braking and the torque caused by friction braking may become the braking torque felt by the driver. At this time, even a slight torque change causes the driver to feel a jerk. Therefore, in the torque blending section, control of heterogeneous torques must be performed as precisely and smoothly as possible.

The technical problem to be solved through embodiments of the present invention is to provide a battery pack that can support smooth torque blending control when regenerative braking of a vehicle ends, and a DC/DC converter control method of a battery management system.

A battery management system installed in a vehicle equipped with a first battery for motor driving, a second battery for electric load, and a DC/DC converter connected between the first and second batteries according to an embodiment to solve the above problems. The DC/DC converter control method includes controlling the output voltage of the DC/DC converter to a first voltage as the vehicle enters the regenerative braking mode, and when termination of the regenerative braking mode is requested, the first voltage It may include changing the output voltage change rate of the DC/DC converter depending on whether the battery is fully charged, and reducing the output voltage of the DC/DC converter to a second voltage based on the output voltage change rate. .

The changing step may include setting the output voltage change rate to a first value when the first battery is in a fully charged state.

The changing step may further include setting the output voltage change rate to a second value greater than the first value if the first battery is not in a fully charged state.

The DC/DC converter control method may further include determining whether the first battery is fully charged according to the state of charge of the first battery or the voltage of the first battery.

Accordingly, a step of changing the rate of change of the regenerative braking torque may be further included.

In addition, a battery pack installed in a vehicle having a first battery for driving a motor, a second battery for an electrical load, and a DC/DC converter connected between the first and second batteries according to an embodiment of the present invention is the vehicle. When entering this regenerative braking mode, the output voltage of the DC/DC converter is controlled to the first voltage, and when termination of the regenerative braking mode is requested, the DC/DC is set differently depending on whether the first battery is fully charged. It may include a first controller that reduces the output voltage of the DC/DC converter to a second voltage based on the rate of change of the output voltage of the converter.

The first controller controls the output voltage change rate to a first value when the first battery is in a fully charged state when the end of the regenerative braking mode is requested, and when the end of the regenerative braking mode is requested, the first battery is in a fully charged state. Alternatively, the output voltage change rate may be controlled to a second value greater than the first value.

The battery pack may further include a battery management system that determines whether the first battery is fully charged based on the state of charge of the first battery or the voltage of the first battery.

The battery pack may include the DC/DC converter.

The first controller may be a converter controller that controls the output voltage of the DC/DC converter.

The first controller may be a battery management system.

According to an embodiment of the present invention, smooth torque blending control is possible when regenerative braking of a vehicle ends, and overcharging of the battery can be prevented in this process.

Figure 1 schematically shows a vehicle control system according to an embodiment of the present invention.
2A and 2B show examples of controlling the braking torque of a vehicle in a vehicle control system according to an embodiment of the present invention.
Figure 3 shows examples of controlling the output voltage of a DC/DC converter in a vehicle control system according to an embodiment of the present invention.
Figure 4 schematically shows a DC/DC converter control method in a vehicle control system according to an embodiment of the present invention.

Hereinafter, with reference to the attached drawings, various embodiments will be described in detail so that those skilled in the art can easily perform them. Embodiments may be implemented in various different forms and are not limited to the embodiments described herein.

In order to clearly describe the embodiments, parts not related to the description are omitted, and identical or similar components are assigned the same reference numbers throughout the specification. Therefore, reference numbers of components used in previous drawings can be used in the next drawing.

In addition, since the size and thickness of each component shown in the drawings are arbitrarily shown for convenience of explanation, the embodiments are not necessarily limited to what is shown. In order to clearly express multiple layers and areas in the drawing, the thickness and area may be exaggerated.

Electrically connecting two components includes not only directly connecting the two components, but also connecting the two components via another component. Other components may include switches, resistors, capacitors, etc. In describing embodiments, the expression to connect means to connect electrically, if there is no expression to connect directly.

Hereinafter, a vehicle control system including a battery management system and a DC/DC converter control method of the vehicle control system according to an embodiment of the present invention will be described in detail with reference to the necessary drawings.

Figure 1 schematically illustrates a vehicle control system according to an embodiment of the present invention, and parts that are not relevant to the description are omitted to clearly describe the embodiment. In addition, Figures 2A and 2B show examples of controlling the braking torque of a vehicle in a vehicle control system according to an embodiment of the present invention, and Figure 3 shows a DC/DC converter in a vehicle control system according to an embodiment of the present invention. Examples of controlling the output voltage are shown.

Referring to FIG. 1, the vehicle control system 100 according to an embodiment of the present invention includes a main battery 110, an auxiliary battery 120, a DC/DC converter (DC to DC converter) 130, and a converter controller 140. ), a battery management system (BMS) 150, a vehicle controller (Hybrid Control Unit, or Vehicle Control Unit) 160, a regenerative braking system 170, and a friction braking system 180. there is.

The main battery 110 is a high-voltage battery that provides driving energy (electrical energy) to the vehicle's driving motor (not shown).

The auxiliary battery 120 is a battery for the vehicle's electrical load and is a low-voltage battery.

The DC/DC converter 130 is connected between the main battery 110 and the auxiliary battery 120, and can convert the output voltage of the main battery 110 into the charging voltage of the auxiliary battery 120. That is, the DC/DC converter 130 can convert the high voltage output of the main battery 110 into a low voltage and then output it to the auxiliary battery 120.

The converter controller 140 can control the output voltage of the DC/DC converter 130. Here, the output voltage of the DC/DC converter 130 is determined by at least one of the converter controller 140, BMS 150, and vehicle controller 160, and is determined by the vehicle's driving mode (regenerative braking mode, friction braking mode). etc.), whether the main battery 110 is charged, the state of charge (SOC) of the main battery 110, the voltage of the main battery 110, and whether a high-voltage electric load is driven.

The converter controller 140 may increase the output voltage of the DC/DC converter 130 in order to store as much electrical energy as possible in the auxiliary battery 120 in the charging mode of the main battery 110. On the other hand, the converter controller 140 consumes power of the main battery 110 by reducing the output voltage of the DC/DC converter 130 in the discharge mode of the main battery 110 compared to the charging mode of the main battery 110. can be minimized. For example, the converter controller 140 controls the output voltage of the DC/DC converter 130 to 15V in the charging mode of the main battery 110, and the DC/DC converter 130 in the discharging mode of the main battery 110. ) can be controlled to 13V. Hereinafter, for convenience of explanation, the output voltage of the DC/DC converter 130 in the charging mode of the main battery 110 will be referred to as 'first voltage', and the DC/DC in the discharging mode of the main battery 110 will be referred to as 'first voltage'. The output voltage of the converter 130 is called 'second voltage' and is used.

While the vehicle is driving in regenerative braking mode, the driving motor of the vehicle generates back electromotive force to charge the main battery 110. Accordingly, while the vehicle is traveling in regenerative braking mode, the main battery 110 operates in charging mode, and the converter controller 140 can control the output voltage of the DC/DC converter 130 to the first voltage. When the regenerative braking mode is terminated due to the charging of the main battery 110, driver operation (brake pedal or accelerator pedal operation, etc.), the converter controller 140 converts the output voltage of the DC/DC converter 130 to the second voltage. Change to

Meanwhile, when a regenerative braking termination situation occurs, the converter controller 140 changes the output voltage of the DC/DC converter 130 from the first voltage to the second voltage, instead of immediately changing the output voltage of the DC/DC converter 130. It may have a section where it gradually decreases from the first voltage to the second voltage. At this time, the rate of change (output voltage change slope) of the output voltage of the DC/DC converter 130 may be controlled differently depending on the charging state of the main battery 110. In this document, the output voltage change rate of the DC/DC converter 130 represents the rate at which the output voltage of the DC/DC converter 130 changes over time. When regenerative braking is terminated by the full charge of the main battery 110, the braking torque of the vehicle is changed from the braking torque generated by the regenerative braking system 170 (hereinafter referred to as 'regenerative braking torque') to the friction braking system 180. ) is gradually converted to the braking torque generated by (hereinafter referred to as 'friction braking torque'). In this document, in the process where the vehicle's braking torque is converted from regenerative braking torque to friction braking torque, the section in which the regenerative braking torque and friction braking torque are blended to form the vehicle's braking torque is called the 'torque blending section'. do.

The braking torque of the vehicle felt by the driver in the torque blending section where the braking torque of the vehicle is converted from regenerative braking torque to friction braking torque corresponds to the sum of the regenerative braking torque and friction braking torque. Therefore, if the balance between the regenerative braking torque and the friction braking torque is broken during the torque blending section, the vehicle's braking torque changes, and even a slight change in the braking torque can cause the driver to feel a jolting feeling of strangeness. In order to prevent this heterogeneity, control of different types of braking torque must be performed as precisely and smoothly as possible. However, the actuator of the regenerative braking system 170 that generates the regenerative braking torque and the actuator of the friction braking system 180 that generates the friction braking torque have different reactivity, so it is not easy to precisely create a single braking torque. In particular, the shorter the torque blending section, the more difficult it is to control the balance between the two braking torques.

Therefore, in the vehicle control system 100 according to an embodiment of the present invention, when regenerative braking is terminated by charging the main battery 110, the rate of change (change slope) of the required torque required for the regenerative braking system 170 is changed. , When regenerative braking is terminated for other reasons, the rate of change in torque required for the regenerative braking system 170 is controlled to be smaller, and the braking torque of the vehicle is converted from regenerative braking torque to friction braking torque due to the full charge of the main battery 110. The length of the torque blending section can be increased. In this document, the rate of change of torque refers to the rate at which the corresponding torque changes over time.

FIG. 2A shows, as an example, the change in braking torque when regenerative braking is terminated due to charging of the main battery 110, and FIG. 2B illustrates the change in braking torque when regenerative braking is terminated for reasons other than charging of the main battery 110. This is shown using braking torque change as an example. Referring to FIGS. 2A and 2B, the rate of change (TR1) of the regenerative braking torque when the regenerative braking is terminated due to charging of the main battery 110 is the rate of change (TR1) of the regenerative braking torque when the regenerative braking is terminated for another reason ( TR2), and as a result, the torque blending section when regenerative braking is terminated due to charging of the main battery 110 may be longer than the torque blending section when regenerative braking is terminated for other reasons.

When regenerative braking ends, the torque required for the regenerative braking system 170 and the friction braking system 180 may be set by the vehicle controller 160. When the required torque (or required torque change rate) of the regenerative braking system 170 and the friction braking system 180 is determined, the vehicle controller 160 operates the actuators of the regenerative braking system 170 and the friction braking system 180 in response to this. Control signals for controlling can be output to the regenerative braking system 170 and the friction braking system 180, respectively.

Meanwhile, increasing the torque blending section by adjusting the rate of change (slope) of the regenerative braking torque may increase the regenerative braking time and cause overcharging of the main battery 110, which may lead to vehicle safety problems.

Accordingly, the vehicle control system 100 according to an embodiment of the present invention performs torque blending by controlling the change rate of the torque required for the regenerative braking system 170 when the regenerative braking termination situation is due to the full charge of the main battery 110. In addition to increasing the section, overcharging of the main battery 110 can be prevented by gently adjusting the rate of change (falling slope) of the output voltage of the DC/DC converter 130. Referring to FIG. 3, the output voltage change rate (VR1) of the DC/DC converter 130 when the regenerative braking is terminated due to charging of the main battery 110 is the DC/DC when the regenerative braking is terminated for other reasons. It may be set to be smaller than the output voltage change rate (VR2) of the converter 130. Accordingly, when regenerative braking is terminated by charging the main battery 110, the energy used to charge the auxiliary battery 120 increases in the process of terminating regenerative braking, and as a result, even if the torque blending section is increased, the main battery 110 is fully charged. Overcharging of the battery 110 can be prevented. Therefore, when regenerative braking ends when the main battery 110 is fully charged, not only is smooth torque blending control possible by increasing the torque blending section, but it also prevents the main battery 110 from being overcharged due to the increase in the torque blending section. can do.

Whether the main battery 110 is fully charged may be determined by the BMS 150. The BMS 150 may determine that the main battery 110 is in a fully charged state if the SOC of the main battery 110 is greater than or equal to the threshold or the voltage of the main battery 110 is greater than or equal to the threshold. On the other hand, if the SOC of the main battery 110 is less than the threshold and the voltage of the main battery 110 is also less than the threshold, the BMS 150 may determine that the main battery 110 is not in a fully charged state. Here, the threshold used to determine whether the main battery 110 is fully charged may be an SOC value and a voltage value set in response to the fully charged state of the main battery 110.

The output voltage of the DC/DC converter 130 at the end of regenerative braking may be determined by the converter controller 140. That is, at the end of regenerative braking, the converter controller 140 receives the full charge determination result of the main battery 110 from the BMS 150 and, based on this, determines the output voltage change rate of the DC/DC converter 130 in the torque blending section. You can decide.

The output voltage of the DC/DC converter 130 at the end of regenerative braking may be determined by the BMS 150. That is, the BMS 150 may determine the output voltage change rate target value of the DC/DC converter 130 in the torque blending section according to the result of the full charge determination result of the main battery 110 at the end of regenerative braking. In this case, the BMS 150 transmits a control signal corresponding to the determined voltage change rate target to the converter controller 140, and the converter controller 140 operates in the torque blending section based on the voltage change rate target determined by the BMS 150. The output voltage of the DC/DC converter 130 can be controlled.

The output voltage of the DC/DC converter 130 at the end of regenerative braking may be determined by the vehicle controller 140. That is, the vehicle controller 140 receives the full charge determination result of the main battery 110 at the end of regenerative braking from the BMS 150, and based on this, sets the target output voltage change rate of the DC/DC converter 130 in the torque blending section. can be decided. In this case, the vehicle controller 160 transmits a control signal corresponding to the determined voltage change rate target to the converter controller 140, and the converter controller 140 performs torque blending based on the voltage change rate target determined by the vehicle controller 160. A target value for the output voltage change rate of the DC/DC converter 130 in the section can be set, and based on this, the output voltage of the DC/DC converter 130 in the torque blending section can be controlled.

Meanwhile, the BMS 150 and the vehicle controller 160 may each determine the target output voltage or voltage change rate of the DC/DC converter 150 depending on the situation, and transmit corresponding control signals to the converter controller 140, respectively. there is. Accordingly, the converter controller 140, which has received both control signals for the voltage change rate from the BMS 150 and the vehicle controller 160, selects one of them and operates the DC/DC converter 130 based on the selected control signal. ) can control the output voltage. In this case, the BMS 150 determines the output voltage change rate of the DC/DC converter 130 based on whether the main battery 110 is charged, the state of charge (SOC) of the main battery 110, and the voltage of the main battery 110. The target value may be determined, and a control signal for the voltage change rate may be transmitted to the converter controller 140 in response to this. In addition, the vehicle controller 160 determines the output voltage change rate target value of the DC/DC converter 130 based on the vehicle's driving condition and whether or not the high-voltage electric load is driven, and in response, converter controller 140 adjusts the voltage change rate. Control signals can be transmitted. The converter controller 140, which receives both the target output voltage or voltage change rate of the DC/DC converter 130 from the BMS 150 and the vehicle controller 160, can select one of the two according to preset selection conditions. For example, when regenerative braking is terminated by the full charge of the main battery 110, the BMS 150 sets the target voltage change rate lower than the default value in the torque blending section and sends the corresponding control signal to the converter. It can be output to the controller 140. In addition, the vehicle controller 160 sets the default value in the torque blending section as the voltage change rate target regardless of whether the battery 110 is fully charged at the end of regenerative braking, and sends the corresponding control signal to the converter controller 140. Can be printed. In this case, the converter controller 140 gives priority to the control signal received from the BMS 150 according to preset selection conditions, and based on the control signal for the voltage change rate received from the BMS 150, in the torque blending section. The output voltage of the DC/DC converter 130 can be controlled.

The regenerative braking system 170 is a system that controls regenerative braking to charge the main battery 110 while decelerating the vehicle. The regenerative braking system 170 includes an actuator (not shown) for generating regenerative braking torque using the vehicle's drive motor (not shown), and controls it based on a control signal received from the vehicle controller 160. The output of regenerative braking torque can be controlled.

The friction braking system 180 is a system for decelerating the vehicle due to frictional force. The friction braking system 180 includes an actuator (not shown) for controlling a brake disc pad, etc. to generate friction braking torque, and controls it based on a control signal received from the vehicle controller 160 to generate friction braking torque. Output can be controlled.

In the vehicle control system 100 described above, the BMS 150 may be packaged with at least one of the main battery 110 and the auxiliary battery 120 to form a battery pack. Additionally, the BMS 150 may be packaged with the converter controller 140 within one battery pack.

Meanwhile, FIG. 1 shows an example where the converter controller 140 exists separately from the BMS 150 and the vehicle controller 160 in the vehicle, but the present invention is not limited to this. The functionality of converter controller 140 may be implemented within BMS 150 or vehicle controller 160.

Figure 4 schematically shows a DC/DC converter control method of a vehicle control system according to an embodiment of the present invention.

Referring to FIG. 4, according to an embodiment of the present invention, the vehicle control system 100 of the vehicle changes the output voltage of the DC/DC converter 130 to the first voltage as the vehicle enters the regenerative braking mode (S100). (See V2 in FIG. 3) (S110).

In step S110, when the vehicle starts operating in regenerative braking mode, the vehicle control system 100 gradually increases the output voltage of the DC/DC converter 130 from the second voltage (see V1 in FIG. 3) to the first voltage. can be increased.

Thereafter, when the end of regenerative braking is requested (S120), and the main battery 110 at this time is in a fully charged state (S130), the vehicle control system 100 increases the torque blending section and The output voltage change rate of the /DC converter 130 is controlled to the first value (S140).

Meanwhile, in step S130, whether the main battery 110 is fully charged may be determined by comparing the SOC or voltage of the main battery 110 with a threshold. For example, if the SOC of the main battery 110 is above the threshold or the voltage of the main battery 110 is above the threshold, it may be determined that the main battery 110 is in a fully charged state. Additionally, for example, if the SOC of the main battery 110 is less than the threshold and the voltage of the main battery 110 is less than the threshold, it may be determined that the main battery 110 is not in a fully charged state.

In step S140, the vehicle control system 100 reduces the required torque change rate (see TR1 in FIG. 2A) of the regenerative braking system 170 through the vehicle controller 160, thereby reducing the torque blending section in the regenerative braking termination process. can be increased.

Meanwhile, when end of regenerative braking is requested (S120), the vehicle control system 100 of the vehicle sets the torque blending section during the end of regenerative braking to the normal state if the main battery 110 is not fully charged (S130). and the output voltage change rate of the DC/DC converter 130 is controlled to a second value greater than the first value (S150).

In step S150, the torque blending section in the normal state is set to have a shorter length than the torque blending section in step S140. That is, in step S150, the vehicle control system 100 sets the required torque change rate of the regenerative braking system 170 to an increased value (see TR2 in FIG. 2b) than in step S140 through the vehicle controller 160. , the torque blending section is controlled to be shorter than in step S140.

In step S150, the second value may be greater than the first value. That is, the output voltage of the DC/DC converter 130 may fall more gently when the change rate changes to the first value than when the change rate changes to the second value.

In steps S140 and S150, the output voltage change rate of the DC/DC converter 130 may be determined by any one of the converter controller 140, BMS 150, and vehicle controller 160.

For example, when regenerative braking ends, the converter controller 140 receives the full charge determination result of the main battery 110 from the BMS 150 and, based on this, output voltage of the DC/DC converter 130 in the torque blending section. The rate of change can be determined.

Additionally, for example, at the end of regenerative braking, the BMS 150 may determine the target output voltage change rate of the DC/DC converter 130 in the torque blending section according to the result of determining that the main battery 110 is fully charged.

In addition, for example, when regenerative braking ends, the vehicle controller 140 receives the result of determining the full charge of the main battery 110 from the BMS 150, and based on this, the DC/DC converter 130 in the torque blending section The output voltage change rate target value can also be determined.

In addition, for example, when regenerative braking ends, the BMS 150 and the vehicle controller 160 each determine the target output voltage or output voltage change rate of the DC/DC converter 150 and send the corresponding control signals to the converter controller ( 140), the converter controller 140 may select one of these according to preset selection conditions. When regenerative braking is terminated by charging the main battery 110, the converter controller 140 may select the control signal received from the BMS 150 according to preset selection conditions. At this time, the control signal received from the BMS 150 may correspond to an output voltage change rate (first value) set lower than the default value in the torque blending section. Meanwhile, when regenerative braking is terminated for reasons other than charging of the main battery 110, the converter controller 140 may select a control signal received from the vehicle controller 160. At this time, the control signal received from the vehicle controller 160 may correspond to the default output voltage change rate (second value) in the torque blending section.

According to the above-described embodiment of the present invention, the vehicle control system 100 controls the rate of change of the torque required for the regenerative braking system 170 when the regenerative braking termination situation is due to the full charge of the main battery 110. In addition to increasing the blending section, the output voltage change rate (falling slope) of the DC/DC converter 130 is gently adjusted. Accordingly, when regenerative braking is terminated due to the full charge of the main battery 110, not only is smooth torque blending control possible due to an increase in the torque blending section, but the increase in the torque blending section also prevents the main battery 110 from being overcharged. It can be prevented.

The drawings and detailed description of the invention described so far are merely illustrative of the present invention, and are used only for the purpose of explaining the present invention, and are not used to limit the meaning or scope of the present invention described in the claims. That is not the case. Therefore, those skilled in the art will understand that various modifications and other equivalent embodiments are possible therefrom. Therefore, the true scope of technical protection of the present invention should be determined by the technical spirit of the appended claims.

100: Vehicle control system
110: main battery
120: Auxiliary battery
130: DC/DC converter
140: converter controller
150: BMS
160: vehicle controller
170: Regenerative braking system
180: Friction braking system

Claims (9)

It is installed in a vehicle equipped with a first battery for driving a motor, a second battery for electric load, a DC/DC converter connected between the first and second batteries, and a converter controller that controls the output voltage of the DC/DC converter. In the DC/DC converter control method of the battery management system,
As the vehicle enters the regenerative braking mode, controlling the output voltage of the DC/DC converter to a first voltage through the converter controller,
When termination of the regenerative braking mode is requested, changing the output voltage change rate of the DC/DC converter depending on whether the first battery is fully charged, and
Based on the changed output voltage change rate, a DC/DC converter control method comprising reducing the output voltage of the DC/DC converter to a second voltage through the converter controller. According to paragraph 1,
The above changing steps are:
A DC/DC converter control method comprising setting the output voltage change rate to a first value when the first battery is in a fully charged state. According to paragraph 2,
The above changing steps are:
If the first battery is not fully charged, the DC/DC converter control method further includes setting the output voltage change rate to a second value greater than the first value. According to paragraph 1,
A DC/DC converter control method further comprising determining whether the first battery is fully charged according to the state of charge of the first battery or the voltage of the first battery. It is installed in a vehicle equipped with a first battery for driving a motor, a second battery for electric load, a DC/DC converter connected between the first and second batteries, and a converter controller that controls the output voltage of the DC/DC converter. In the battery pack,
The output voltage of the DC/DC converter is controlled through the converter controller, and when the vehicle enters the regenerative braking mode, the output voltage of the DC/DC converter is controlled to the first voltage, and the end of the regenerative braking mode is controlled. When requested, a battery pack including a first controller that reduces the output voltage of the DC/DC converter to a second voltage based on the output voltage change rate of the DC/DC converter, which is set differently depending on whether the first battery is fully charged. . According to clause 5,
The first controller controls the output voltage change rate to a first value when the first battery is in a fully charged state when the end of the regenerative braking mode is requested, and when the end of the regenerative braking mode is requested, the first battery is in a fully charged state. Alternatively, the battery pack controls the output voltage change rate to a second value greater than the first value. According to clause 5,
A battery pack further comprising a battery management system that determines whether the first battery is fully charged based on the state of charge of the first battery or the voltage of the first battery. delete According to clause 5,
The first controller is a battery pack that is a battery management system.

Images