CN111371082B

CN111371082B - High-voltage direct-current bus energy control system and method and automobile

Info

Publication number: CN111371082B
Application number: CN201811598077.8A
Authority: CN
Inventors: 杨志; 张雪冰; 喻皓; 廖赟; 张永红; 江海
Original assignee: Guangzhou Automobile Group Co Ltd
Current assignee: Gac Aion New Energy Vehicle Co ltd
Priority date: 2018-12-26
Filing date: 2018-12-26
Publication date: 2021-01-22
Anticipated expiration: 2038-12-26
Also published as: CN111371082A

Abstract

The application relates to a high-voltage direct-current bus energy control system, a high-voltage direct-current bus energy control method and an automobile; wherein, high voltage direct current bus energy control system includes: the controller is respectively connected with the first voltage sampling module, the second voltage sampling module, the bidirectional DC/DC power conversion module and the bus control device of the controller; the bus control device is connected between the first voltage sampling module and the second voltage sampling module; the second voltage sampling module is connected with the bidirectional DC/DC power conversion module; the bus control device comprises a switch module connected with the controller; the switch module is respectively connected with the first voltage sampling module, the second voltage sampling module and the high-voltage direct-current bus interface; the method and the device can realize orderly charging and discharging of the energy of the high-voltage bus, and ensure reliability and safety.

Description

High-voltage direct-current bus energy control system and method and automobile

Technical Field

The application relates to the technical field of automotive electronic design, in particular to a high-voltage direct-current bus energy control system and method and an automobile.

Background

With the rapid development of new energy automobiles, the integration and high efficiency of system components are more and more emphasized. The high-voltage direct current bus is used as a key device for connecting the high-voltage energy storage device and the high-voltage electric parts, and energy of the high-voltage direct current bus needs to be charged and discharged respectively in the high-voltage electrifying and high-voltage descending processes.

In the implementation process, the inventor finds that at least the following problems exist in the conventional technology: at present, in the case that a plurality of high-voltage power utilization parts correspond to a plurality of high-voltage direct-current bus interfaces, the conventional technology cannot realize ordered charging and discharging of high-voltage bus energy.

Disclosure of Invention

In view of the above, there is a need to provide a high voltage dc bus energy control system, a method and an automobile, which can realize orderly charging and discharging of specific high voltage bus energy.

In order to achieve the above object, in one aspect, an embodiment of the present invention provides an energy control system for a high-voltage direct current bus, including:

the bidirectional DC/DC power conversion device comprises a controller, a first voltage sampling module, a second voltage sampling module, a bidirectional DC/DC power conversion module and a bus control device, wherein the first voltage sampling module, the second voltage sampling module, the bidirectional DC/DC power conversion module and the bus control device are respectively connected with the controller; the bus control device is connected between the first voltage sampling module and the second voltage sampling module; the second voltage sampling module is connected with the bidirectional DC/DC power conversion module;

the first voltage sampling module is connected with the high-voltage energy storage device; the bidirectional DC/DC power conversion module is connected with the low-voltage energy storage device; the bus control device is connected with the high-voltage direct-current bus interface; the bus control device comprises a switch module connected with the controller; the switch module is respectively connected with the first voltage sampling module, the second voltage sampling module and the high-voltage direct-current bus interface;

the controller is used for controlling the bidirectional DC/DC power conversion module to take electricity from the low-voltage energy storage device or charge the low-voltage energy storage device according to the first voltage sampling module, the second voltage sampling module and the sampling voltage before and after the switch module is switched on and switched off, so that the high-voltage direct current bus is charged and discharged.

In one embodiment, the bus control device further comprises a current sampling module connected with the controller; the switch module comprises a high-voltage direct-current bus switch unit and a charge-discharge switch unit which are respectively connected with the controller;

one end of the high-voltage direct current bus switch unit is connected with the first voltage sampling module through the current sampling module, and the other end of the high-voltage direct current bus switch unit is connected with the high-voltage direct current bus interface and one end of the charge and discharge switch unit; the other end of the charge and discharge switch unit is connected with the second voltage sampling module;

when the high-voltage direct-current bus discharges, the controller monitors whether the sampling current of the current sampling module meets a preset condition or not, and carries out corresponding on-off control on the high-voltage direct-current bus switch unit and the charge and discharge switch unit when the sampling current meets the preset condition.

In one embodiment, the high-voltage direct current bus switch unit comprises a first high-voltage direct current bus switch and a second high-voltage direct current bus switch which are respectively connected with the controller; the charge and discharge switch unit comprises a first charge and discharge switch and a second charge and discharge switch which are respectively connected with the controller;

one end of the first high-voltage direct-current bus switch is connected with the first voltage sampling module through the current sampling module, and the other end of the first high-voltage direct-current bus switch is connected with the high-voltage direct-current bus interface and is connected with the second voltage sampling module through the first charge-discharge switch;

one end of the second high-voltage direct-current bus switch is connected with the first voltage sampling module through the current sampling module, and the other end of the second high-voltage direct-current bus switch is connected with the high-voltage direct-current bus interface and is connected with the second voltage sampling module through the second charge-discharge switch.

On the other hand, the embodiment of the invention also provides a high-voltage direct current bus charging method based on the high-voltage direct current bus energy control system, which comprises the following steps:

the bidirectional DC/DC power conversion module is switched to a stop working mode;

the control switch module is used for conducting a charge-discharge loop between the low-voltage energy storage device and the high-voltage direct-current bus;

acquiring an absolute value of a difference value of a sampling voltage of the second voltage sampling module and a sampling voltage of the first voltage sampling module;

if the absolute value is larger than the preset target value, controlling the bidirectional DC/DC power conversion module to switch to a boosting working mode and charge the high-voltage direct-current bus until the absolute value is smaller than or equal to the preset target value;

and if the absolute value is less than or equal to the preset target value, controlling the bidirectional DC/DC power conversion module to switch to a stop working mode, and controlling the switch module to disconnect a charge-discharge loop between the low-voltage energy storage device and the high-voltage direct current bus and switch on a high-voltage direct current bus loop between the high-voltage energy storage device and the high-voltage direct current bus.

In one embodiment, the step of closing the switch module to conduct the charge-discharge loop between the low-voltage energy storage device and the high-voltage direct-current bus includes:

a first charge-discharge switch and a second charge-discharge switch of the switch module are closed; or the like, or, alternatively,

closing a first charge-discharge switch and a second charge-discharge switch of the switch module, and disconnecting any one of a first high-voltage direct-current bus switch and a second high-voltage direct-current bus switch of the switch module;

the control switch module breaks the charge-discharge circuit between the low-voltage energy storage device and the high-voltage direct-current bus, and conducts the high-voltage direct-current bus circuit between the high-voltage energy storage device and the high-voltage direct-current bus, and the control switch module comprises the following steps:

and disconnecting the first charge-discharge switch and the second charge-discharge switch, and closing the first high-voltage direct-current bus switch and the second high-voltage direct-current bus switch.

The embodiment of the invention provides a high-voltage direct current bus discharging method based on the high-voltage direct current bus energy control system, which comprises the following steps:

acquiring sampling current of a current sampling module in a bus control device; if the sampling current is less than or equal to the target current, controlling the switch module and disconnecting a high-voltage direct current bus circuit between the high-voltage energy storage device and the high-voltage direct current bus;

acquiring a first absolute value of a difference value of a sampling voltage of a second voltage sampling module and a sampling voltage of a first voltage sampling module;

if the first absolute value is larger than a first preset target value, controlling the bidirectional DC/DC power conversion module to switch to a boosting working mode and charge the high-voltage direct-current bus until the first absolute value is smaller than or equal to the first preset target value;

if the first absolute value is smaller than or equal to the first preset target value, the bidirectional DC/DC power conversion module is controlled to be switched to a work stopping mode, and the switch module is controlled to conduct a charge-discharge loop between the low-voltage energy storage device and the high-voltage direct current bus;

acquiring a second absolute value of a difference value between the sampling voltage of the second voltage sampling module and the target voltage;

if the second absolute value is larger than a second preset target value, controlling the bidirectional DC/DC power conversion module to switch to a voltage reduction working mode, and performing voltage reduction conversion on the voltage of the high-voltage direct current bus until the second absolute value is smaller than or equal to the second preset target value;

and if the second absolute value is less than or equal to the second preset target value, controlling the bidirectional DC/DC power conversion module to switch to a work stopping mode, and controlling the switch module to disconnect a charge-discharge loop between the low-voltage energy storage device and the high-voltage direct current bus.

In one embodiment, if the sampled current is less than or equal to the target current, the step of controlling the switch module and disconnecting the high-voltage direct current bus circuit between the high-voltage energy storage device and the high-voltage direct current bus comprises:

disconnecting a first high-voltage direct-current bus switch and a second high-voltage direct-current bus switch of the switch module; or the like, or, alternatively,

disconnecting a first high-voltage direct-current bus switch and a second high-voltage direct-current bus switch in the switch module; any one of a first charge-discharge switch and a second charge-discharge switch of the switch module is closed;

the step of controlling the switch module to conduct the charge-discharge loop between the low-voltage energy storage device and the high-voltage direct-current bus comprises the following steps:

closing the first charge-discharge switch and the second charge-discharge switch;

the step of controlling the switch module to disconnect the charging and discharging loop comprises the following steps:

and disconnecting the first charge-discharge switch and the second charge-discharge switch.

The embodiment of the invention provides a low-voltage energy storage device charging method based on the high-voltage direct current bus energy control system, which comprises the following steps:

and if the absolute value is less than or equal to the preset target value, the bidirectional DC/DC power conversion module is controlled to be switched to a stop working mode, the switch module is controlled to conduct a high-voltage direct-current bus circuit between the high-voltage energy storage device and the high-voltage direct-current bus, and the bidirectional DC/DC power conversion module is controlled to be switched to a step-down working mode to perform step-down conversion on the voltage of the high-voltage direct-current bus and transmit the voltage to the low-voltage energy storage.

In one embodiment, the step of controlling the switch module to conduct the charge-discharge loop between the low-voltage energy storage device and the high-voltage direct-current bus includes:

the step of control switch module switch on high voltage direct current bus return circuit between high pressure energy memory and the high voltage direct current bus includes:

and closing the first high-voltage direct-current bus switch and the second high-voltage direct-current bus switch.

An automobile comprises any one of the high-voltage direct-current bus energy control systems.

One of the above technical solutions has the following advantages and beneficial effects:

according to the method, for the situation that a plurality of high-voltage power utilization parts correspond to a plurality of high-voltage direct-current bus interfaces, the on-off of a switch module in a bus control device corresponding to a specific high-voltage direct-current bus is controlled according to the sampling voltage of the high-voltage direct-current bus and a charging and discharging circuit, and the bidirectional DC/DC power conversion module is used for realizing ordered charging and discharging of the energy of the specific high-voltage bus, so that the reliability and the safety are ensured. For current need use different control system respectively to realize charging and discharging the energy of high voltage direct current generating line, this application adopts same set of control system can satisfy these two kinds of functions simultaneously, has realized integrating with high efficiency.

Drawings

Other features, objects and advantages of the present application will become more apparent upon reading of the following detailed description of non-limiting embodiments thereof, made with reference to the accompanying drawings in which:

FIG. 1 is a first schematic block diagram of an embodiment of a high voltage direct current bus energy control system;

FIG. 2 is a second schematic block diagram of an embodiment of a high voltage direct current bus energy control system;

FIG. 3 is a third schematic block diagram of an embodiment of an energy control system for a high voltage direct current bus;

FIG. 4 is a fourth schematic block diagram of an embodiment of an energy control system for a high voltage direct current bus;

FIG. 5 is a first schematic diagram of a charging process for an exemplary HVDC bus;

FIG. 6 is a second schematic diagram of a charging process for the HVDC bus according to an embodiment;

FIG. 7 is a first schematic diagram of a discharging process of the HVDC bus according to an embodiment;

FIG. 8 is a second schematic diagram of a discharging process of the HVDC bus according to an embodiment;

FIG. 9 is a first schematic diagram of a low voltage energy storage device charging process according to an embodiment;

fig. 10 is a second schematic diagram illustrating a charging process of the low-voltage energy storage device according to an embodiment.

Detailed Description

In order to make the objects, technical solutions and advantages of the present application more apparent, the present application is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present application and are not intended to limit the present application.

The high-voltage direct current bus is used as a key device for connecting the high-voltage energy storage device and the high-voltage electric parts, and energy of the high-voltage direct current bus needs to be charged and discharged respectively in the high-voltage electrifying and high-voltage descending processes. In addition, in order to guarantee that the low-voltage power consumption part can meet the continuous power consumption requirement of the low-voltage power, a unidirectional DC/DC power conversion module is usually used for getting power from the high-voltage energy storage device to charge the low-voltage energy storage device, so that the low-voltage energy storage device is ensured not to have power shortage risks.

The plurality of high-voltage power utilization parts correspond to the plurality of high-voltage direct-current bus interfaces, and may include a special high-voltage power taking port of a motor controller, a special high-voltage power taking port of a high-voltage air conditioner, a special high-voltage power taking port of a motor, and the like. For the situation that a plurality of high-voltage power utilization parts correspond to a plurality of high-voltage direct-current bus interfaces, how to realize ordered charging and discharging on specific high-voltage bus energy needs to be researched; in addition, for how to realize reliable and safe charging and discharging of the high-voltage bus energy, certain improvement and improvement spaces exist in the aspects of integration level and efficiency index at present.

In one embodiment, as shown in fig. 1, there is provided a high voltage direct current bus energy control system, which may include:

a controller 110 connected to the first voltage sampling module 120, the second voltage sampling module 130, the bidirectional DC/DC power conversion module 140, and the bus control device 150 of the controller 110, respectively; the bus control device 150 is connected between the first voltage sampling module 120 and the second voltage sampling module 130; the second voltage sampling module 130 is connected to the bidirectional DC/DC power conversion module 140;

the first voltage sampling module 120 is connected with the high-voltage energy storage device; the bidirectional DC/DC power conversion module 140 is connected with a low-voltage energy storage device; the bus control device 150 is connected with the corresponding high-voltage direct-current bus interface; the bus control device 150 includes a switch module connected to the controller; the switch module is respectively connected with the first voltage sampling module 120, the second voltage sampling module 130 and the high-voltage direct-current bus interface;

the controller 110 is configured to control the bidirectional DC/DC power conversion module 140 to take power from the low-voltage energy storage device or charge the low-voltage energy storage device according to the first voltage sampling module 120, the second voltage sampling module 130, and the sampled voltages before and after the switch module is turned on and off, so as to charge and discharge the high-voltage DC bus.

Specifically, when the high-voltage direct-current bus is charged and discharged, the controller selects the corresponding switch module of the bus control device and performs corresponding on-off control, and then controls the bidirectional DC/DC power conversion module to take power from the low-voltage energy storage device or charge the low-voltage energy storage device according to the first voltage sampling module, the second voltage sampling module and the sampling voltage before and after the on-off of the switch module, so that the charging and discharging of the high-voltage direct-current bus are completed.

The high-voltage energy storage device is connected with the first voltage sampling module and can be used for storing electric energy; the low-voltage energy storage device is connected with the bidirectional DC/DC power conversion module and is used for storing electric energy;

the first voltage sampling module is connected with the controller and used for sampling voltage and reporting a sampling value to the controller; and the second voltage sampling module is connected with the switch module, the bidirectional DC/DC power conversion module and the controller and used for sampling voltage and reporting the sampling value to the controller.

The switch module is connected with the controller and used for receiving the instruction of the controller to switch on and off the circuit; the high-voltage direct-current bus interface is connected with the switch module and is used for providing an electrical interface for high-voltage electric parts; in one particular example, the switch modules may be respective switches on which the high voltage dc bus is located.

And one end of the bidirectional DC/DC power conversion module is connected with the second voltage sampling module, and the other end of the bidirectional DC/DC power conversion module is connected with the low-voltage energy storage device and used for converting electric energy. It should be noted that the function of the bidirectional DC/DC power conversion module can be implemented by using the existing bidirectional DC/DC converter; the charging and discharging of the energy of the specific high-voltage direct-current bus can be realized through switching of a switch: the conversion function of the electric energy is specifically boosting and reducing voltage, and the boosting is to boost the voltage of the low-voltage energy storage device so as to charge the high-voltage direct-current bus; the voltage reduction is to reduce the voltage of the high-voltage direct-current bus so as to charge the low-voltage energy storage device and realize the discharge of the energy of the high-voltage direct-current bus.

For the situation that a plurality of high-voltage power utilization parts correspond to a plurality of high-voltage direct-current bus interfaces, the on-off of a switch module in a bus control device corresponding to a specific high-voltage direct-current bus is controlled, and the bidirectional DC/DC power conversion module is used for realizing ordered charging and discharging of the energy of the specific high-voltage bus, so that the reliability and the safety are ensured. Need use different control system to realize respectively charging and discharging the energy of high voltage direct current generating line for the prior art, this application adopts one set of control system can satisfy these two kinds of functions simultaneously, has realized integrating with high efficiency.

In a specific example, as shown in fig. 1, the number of the bus bar control devices may be plural; and each bus control device is used for being respectively connected with the corresponding high-voltage direct-current bus interface.

Based on the structure of the application, before the high-voltage bus is precharged and pre-discharged, a secondary line voltage pre-regulation mechanism for increasing the high-voltage bus and pre-charging the high-voltage bus is adopted, namely, the first voltage sampling module and the second voltage sampling module are used for monitoring the voltage difference between the front and the back of the pre-charging switch, under the condition that the voltage difference exceeds the threshold value, the bidirectional DC power conversion module is used for taking electricity from the low-voltage energy storage module, after the voltage difference between the front and the back of the pre-charging switch is adjusted to be smaller than the threshold value, the pre-charging switch is actuated again, under the condition that an external cooling module or a circuit stabilizing component is not required to be added, the high-voltage bus before actuation of the bus.

When charging the energy of the high-voltage direct-current bus: because the high-voltage direct current bus and the high-voltage energy storage device have a pressure difference, when the energy of the high-voltage direct current bus is charged, if the high-voltage direct current bus is improperly controlled, the high impact current is easy to cause damage to components such as a switch; for high-voltage electrification, the traditional technology provides that the problem of impact current is avoided by additionally adding an electric automobile soft start circuit based on a negative temperature coefficient thermistor, but the problem of low integration level exists.

And when discharging the energy of the high-voltage direct-current bus: in order to avoid safety problems caused by residual energy of the high-voltage direct-current bus, the energy of the high-voltage direct-current bus needs to be discharged. For high-voltage low-voltage power supply, the conventional technology proposes to consume the energy of the high-voltage direct-current bus inside the motor through the control of a motor controller, but the problem of energy waste exists.

For another example, in the conventional technology, a DC/DC converter is additionally arranged and placed between a high-voltage energy storage device and a high-voltage direct-current bus switch to charge and discharge a high-voltage direct-current bus, but the integration level is not high.

Compared with the scheme that a DC/DC converter is additionally arranged in the traditional technology and is arranged between a high-voltage energy storage device and a high-voltage direct-current bus switch, the bidirectional DC/DC power conversion module is arranged between a low-voltage energy storage device and a second voltage sampling module, so that ordered charging and discharging of specific high-voltage bus energy can be realized, the conventional unidirectional DC/DC power conversion module can be replaced to take electricity from the high-voltage energy storage device to charge the low-voltage energy storage device, and the integration level is further improved.

In addition, thereby compare in the prior art through the motor controller control with the energy consumption of high voltage direct current bus waste in the motor is inside, this application proposes the energy storage with the high voltage direct current bus at low pressure energy memory to efficiency has been improved.

In the high-voltage direct current bus energy control system, the on-off of the switch module in the bus control device corresponding to the specific high-voltage direct current bus is controlled, and the bidirectional DC/DC power conversion module is used for realizing the ordered charging and discharging of the specific high-voltage bus energy, so that the charging and discharging reliability and safety of the high-voltage direct current bus are ensured in the situation that a plurality of high-voltage power utilization parts correspond to a plurality of high-voltage direct current bus interfaces.

In one embodiment, as shown in fig. 2, there is provided a high voltage dc bus energy control system, which may include:

a controller 210 connected to the first voltage sampling module 220, the second voltage sampling module 230, the bidirectional DC/DC power conversion module 240, and each bus control device 250 of the controller 210; the bus control device 250 is connected between the first voltage sampling module 220 and the second voltage sampling module 230; the second voltage sampling module 230 is connected to the bidirectional DC/DC power conversion module 240;

the first voltage sampling module 220 is connected with the high-voltage energy storage device; the bidirectional DC/DC power conversion module 240 is connected with a low-voltage energy storage device; each bus control device 250 is connected with a corresponding high-voltage direct-current bus interface; bus control device 250 includes a switch module connected to controller 210; the switch module is respectively connected with the first voltage sampling module 220, the second voltage sampling module 230 and the high-voltage direct-current bus interface;

the controller 210 is configured to control the bidirectional DC/DC power conversion module 240 to take power from the low-voltage energy storage device or charge the low-voltage energy storage device according to the first voltage sampling module 220, the second voltage sampling module 230, and the sampled voltages before and after the switch module is turned on and off, so as to charge and discharge the high-voltage DC bus.

In a particular embodiment, bus control device 250 further includes a current sampling module coupled to controller 210; the switch module comprises a high-voltage direct-current bus switch unit and a charge-discharge switch unit which are respectively connected with the controller;

one end of the high-voltage direct current bus switch unit is connected with the first voltage sampling module 220 through the current sampling module, and the other end of the high-voltage direct current bus switch unit is connected with the high-voltage direct current bus interface and one end of the charge and discharge switch unit; the other end of the charge and discharge switch unit is connected with the second voltage sampling module 230;

Specifically, the high-voltage energy storage device is connected with the first voltage sampling module and can be used for storing electric energy; the low-voltage energy storage device is connected with the bidirectional DC/DC power conversion module and is used for storing electric energy;

the first voltage sampling module is connected with the controller and the current sampling module and used for sampling voltage and reporting a sampling value to the controller; and the second voltage sampling module is connected with the charge and discharge switch unit, the bidirectional DC/DC power conversion module and the controller and is used for sampling voltage and reporting the sampling value to the controller. And the current sampling module is connected with the high-voltage direct-current bus switch unit and the controller and is used for sampling current and reporting the sampling value to the controller.

The high-voltage direct-current bus switch unit and the charge-discharge switch unit are respectively connected with the controller and used for receiving the instruction of the controller to switch on and off the circuit; the high-voltage direct current bus interface is connected between the high-voltage direct current bus switch unit and the charge and discharge switch unit and used for providing an electrical interface for high-voltage electric parts.

And one end of the bidirectional DC/DC power conversion module is connected with the second voltage sampling module, and the other end of the bidirectional DC/DC power conversion module is connected with the low-voltage energy storage device and used for converting electric energy.

According to the method, for the situation that a plurality of high-voltage power utilization parts correspond to a plurality of high-voltage direct-current bus interfaces, the on-off of a high-voltage direct-current bus switch unit and a charging and discharging switch unit where a specific high-voltage direct-current bus is located is controlled, and the bidirectional DC/DC power conversion module is used for achieving ordered charging and discharging of specific high-voltage bus energy, so that the reliability and the safety are guaranteed. For current need use different control system respectively to realize charging and discharging the energy of high voltage direct current generating line, this application adopts same set of control system can satisfy these two kinds of functions simultaneously, has realized integrating with high efficiency.

In one embodiment, as shown in fig. 3, there is provided a high voltage dc bus energy control system, which may include:

a controller 310 connected to the first voltage sampling module 320, the second voltage sampling module 330, the bidirectional DC/DC power conversion module 340, and the bus control devices of the controller 310, respectively; the bus control device is connected between the first voltage sampling module 320 and the second voltage sampling module 330; the second voltage sampling module 330 is connected to the bidirectional DC/DC power conversion module 340;

the first voltage sampling module 320 is connected with the high-voltage energy storage device; the bidirectional DC/DC power conversion module 340 is connected with a low-voltage energy storage device; each bus control device is respectively connected with a corresponding high-voltage direct-current bus interface; the bus control device comprises a switch module connected with the controller; the switch modules are respectively connected with the first voltage sampling module 320,

A second voltage sampling module 330 and a high voltage dc bus interface;

the controller 310 is configured to control the bidirectional DC/DC power conversion module 340 to take power from the low-voltage energy storage device or charge the low-voltage energy storage device according to the first voltage sampling module 320, the second voltage sampling module 330, and the sampled voltages before and after the switch module is turned on and off, so as to charge and discharge the high-voltage DC bus.

In a specific embodiment, the bus control apparatus further comprises a current sampling module connected to the controller 310; the switch module comprises a high-voltage direct-current bus switch unit and a charge-discharge switch unit which are respectively connected with the controller 310;

one end of the high-voltage direct current bus switch unit is connected with the first voltage sampling module 320 through the current sampling module, and the other end of the high-voltage direct current bus switch unit is connected with the high-voltage direct current bus interface and one end of the charge and discharge switch unit; the other end of the charge and discharge switch unit is connected with the second voltage sampling module 330;

when the high-voltage direct-current bus discharges, the controller 310 monitors whether the sampling current of the current sampling module meets a preset condition, and performs corresponding on-off control on the high-voltage direct-current bus switch unit and the charge and discharge switch unit when the sampling current meets the preset condition.

In a specific embodiment, the high voltage dc bus switch unit includes a first high voltage dc bus switch and a second high voltage dc bus switch connected to the controller 310; the charge and discharge switch unit comprises a first charge and discharge switch and a second charge and discharge switch which are respectively connected with the controller 310;

one end of the first high-voltage direct-current bus switch is connected with the first voltage sampling module 320 through the current sampling module, and the other end of the first high-voltage direct-current bus switch is connected with the high-voltage direct-current bus interface and is connected with the second voltage sampling module 330 through the first charge-discharge switch;

one end of the second high-voltage direct-current bus switch is connected with the first voltage sampling module 320 through the current sampling module, and the other end of the second high-voltage direct-current bus switch is connected with the high-voltage direct-current bus interface and is connected with the second voltage sampling module 330 through the second charge-discharge switch.

Specifically, the high-voltage energy storage device is connected with the first voltage sampling module and used for storing electric energy; and the low-voltage energy storage device is connected with the bidirectional DC/DC power conversion module and is used for storing electric energy.

The first voltage sampling module is connected with the high-voltage energy storage device, the current sampling module and the controller and used for sampling voltage and reporting a sampling value to the controller; the current sampling module is connected with the current sampling module, the first high-voltage direct-current bus switch, the second high-voltage direct-current bus switch and the controller and used for sampling current and reporting a sampling value to the controller; the second voltage sampling module is connected with the first charge-discharge switch, the second charge-discharge switch, the bidirectional DC/DC power conversion module and the controller and used for sampling voltage and reporting a sampling value to the controller;

the first high-voltage direct-current bus switch is connected with the current sampling module, the high-voltage direct-current bus interface, the first charge-discharge switch and the controller and is used for receiving an instruction of the controller to switch on and off the circuit; the second high-voltage direct-current bus switch is connected with the current sampling module, the high-voltage direct-current bus interface, the second charge and discharge switch and the controller and is used for receiving an instruction of the controller to switch on and off the circuit; the first charge and discharge switch is connected with the second voltage sampling module, the high-voltage direct current bus interface, the first high-voltage direct current bus switch and the controller and used for receiving an instruction of the controller to switch on and off the circuit; the second charge and discharge switch is connected with the second voltage sampling module, the high-voltage direct current bus interface, the second high-voltage direct current bus switch and the controller and used for receiving an instruction of the controller to switch on and off the circuit; the high-voltage direct-current bus interface is connected with the first high-voltage direct-current bus switch, the second high-voltage direct-current bus switch, the first charge and discharge switch and the second charge and discharge switch and is used for providing an electrical interface for high-voltage power utilization parts;

The structure shown in fig. 4 is taken as an example, and the working process of the high-voltage direct-current bus energy control system of the present application is described with reference to a specific embodiment; it should be noted that the relevant components and connection relationships in fig. 4 may correspond to the relevant components and connection relationships in fig. 3 one to one, and are not described herein again.

In an embodiment, a method for charging a high-voltage direct-current bus is provided, which is described by taking an example of applying the method to a controller in the present application, and may include the following steps:

In a specific embodiment, the step of closing the switch module to conduct the charge-discharge loop between the low-voltage energy storage device and the high-voltage direct-current bus includes:

a first charge-discharge switch and a second charge-discharge switch of the switch module are closed;

Specifically, as shown in fig. 5, the method for controlling the charging of the energy of the high-voltage direct-current bus may include the following steps:

step 11: the bidirectional DC/DC power conversion module is switched to a stop working mode;

step 12: charging and discharging switch S_iP(i.e., first charge and discharge switch) and S_iN(i.e., the second charge and discharge switch) are allClosed, except S_iPAnd S_iNThe other charge and discharge switches are turned off;

step 13: determine the sampling voltage V of the voltage sampling module 2 (i.e., the second voltage sampling module)_iAnd a preset target voltage V_HTaking an absolute value of the difference value to see whether the absolute value is not more than a preset target value delta V₁If yes, go to step 15, if no, go to step 14. Wherein the target voltage V is preset_HIs the sampling voltage of the voltage sampling module 1 (i.e. the first voltage sampling module), and the preset target value Δ V₁Is 3V;

step 14: the bidirectional DC/DC power conversion module is switched to a boosting working mode, and the method specifically comprises the following steps:

the bidirectional DC/DC power conversion module gets electricity from the low-voltage energy storage device, performs voltage boosting conversion on the electricity, and outputs the electricity to the ith high-voltage direct current bus so that the ith high-voltage direct current bus is in a charging process, and in the process, the voltage V output to the ith high-voltage direct current bus_iGradually rises to a preset target voltage V_HThe difference of (a) is smaller and smaller;

step 15: the bidirectional DC/DC power conversion module is switched to a stop working mode;

step 16: charging and discharging switch S_iPAnd S_iNAre all disconnected;

and step 17: high-voltage direct-current bus switch K_iP(i.e. first high voltage dc bus switch) and K_iN(i.e. the second high voltage dc bus switch) is closed.

Specifically, as shown in fig. 6, the method for controlling the charging of the energy of the high-voltage direct-current bus may include the following steps:

step 21: the bidirectional DC/DC power conversion module is switched to a stop working mode;

step 22: high-voltage direct-current bus switch K_iPOr K_iNOne of the high-voltage direct-current bus switches is closed, and the other high-voltage direct-current bus switch which is not closed is kept in an open state; charging and discharging switch S_iPAnd S_iNAre all closed except S_iPAnd S_iNThe other charge and discharge switches are turned off;

step 23: judging the sampling voltage V of the voltage sampling module 2_iAnd a preset target voltage V_HTaking an absolute value of the difference value to see whether the absolute value is not more than a preset target value delta V₁If yes, go to step 25, if no, go to step 24. Wherein the target voltage V is preset_HIs the sampling voltage of the voltage sampling module 1, and a preset target value DeltaV₁Is 3V;

step 24: the bidirectional DC/DC power conversion module is switched to a boosting working mode, and the method specifically comprises the following steps:

step 25: the bidirectional DC/DC power conversion module is switched to a stop working mode;

step 26: charging and discharging switch S_iPAnd S_iNAre all disconnected;

step 27: in step 22, another unclosed high voltage dc bus switch is closed.

In one embodiment, a high-voltage direct-current bus discharging method is provided, which is described by taking an example of applying the method to a controller in the application, and includes the following steps:

It should be noted that, in practical applications, the sampling current of the current sampling module is generally polar (positive or negative), and when the high-voltage direct-current bus discharging method provided by the application judges the magnitude relation between the sampling current and the target current, the absolute value of the sampling current can be taken for comparison.

In a specific embodiment, if the sampled current is less than or equal to the target current, the step of controlling the switch module and disconnecting the high-voltage dc bus circuit between the high-voltage energy storage device and the high-voltage dc bus includes:

disconnecting a first high-voltage direct-current bus switch and a second high-voltage direct-current bus switch of the switch module;

Specifically, as shown in fig. 7, the method for controlling the discharge of the energy of the high-voltage direct-current bus may include the following steps:

step 31: the bidirectional DC/DC power conversion module is switched to a stop working mode;

step 32: judging the sampling current I of the current sampling module I_iIs not greater than a preset target current I₁(i.e., the target current), if yes, step 33 is entered, and if no, step 32 is entered. Wherein a target current I is preset₁Is 1A;

step 33: high-voltage direct-current bus switch K_iPAnd K_iNAre all disconnected;

step 34: judging the sampling voltage V of the voltage sampling module 2_iAnd a preset target voltage V_HIs taken as an absolute value (i.e., a first absolute value) to see whether it is not greater than a preset target value Δ V₂(i.e., the first preset target value), if yes, step 36 is entered, and if no, step 35 is entered. Wherein the target voltage V is preset_HIs the sampling voltage of the voltage sampling module 1, and a preset target value DeltaV₂Is 3V;

step 35: the bidirectional DC/DC power conversion module is switched to a boosting working mode, and the method specifically comprises the following steps:

the bidirectional DC/DC power conversion module gets electricity from the low-voltage energy storage device, performs voltage boosting conversion on the electricity, and outputs the electricity to the ith high-voltage direct current bus so that the ith high-voltage direct current bus is in a charging process, and in the process, the voltage V output to the ith high-voltage direct current bus_iGradually rises to a preset target voltage V_HIn the process, the voltage V output to the ith high-voltage direct-current bus_iGradually rises to a preset target voltage V_HThe difference of (a) is smaller and smaller;

step 36: the bidirectional DC/DC power conversion module is switched to a stop working mode;

step 37: charging and discharging switch S_iPAnd S_iNAre all closed;

step 38: judging the sampling voltage V of the voltage sampling module 2_iAnd a preset target voltage V_LThe absolute value (i.e., the second absolute value) of the difference (i.e., the target voltage) is determined to see whether it is not greater than the preset target value Δ V₃(i.e., the second preset target value), if yes, step 40 is entered, and if no, step 39 is entered. Wherein a target voltage V is preset_LIs 60V, a preset target value DeltaV₃Is 3V;

step 39: the bidirectional DC/DC power conversion module is switched to a voltage reduction working mode, and the method specifically comprises the following steps:

the bidirectional DC/DC power conversion module obtains electricity from the ith high-voltage direct-current bus, performs voltage reduction conversion on the voltage of the ith high-voltage direct-current bus, and outputs the voltage to the low-voltage energy storage device, wherein in the process, the voltage V of the ith high-voltage direct-current bus_iGradually dropping to a preset target voltage V_L。

Step 40: the bidirectional DC/DC power conversion module is switched to a stop working mode;

step 41: charging and discharging switch S_iPAnd S_iNIs disconnected.

Specifically, as shown in fig. 8, the method for controlling the discharge of the energy of the high-voltage direct-current bus may include the following steps:

step 51: the bidirectional DC/DC power conversion module is switched to a stop working mode;

step 52: judging the sampling current I of the current sampling module I_iIs not greater than a preset target current I₁If yes, step 53 is entered, and if no, step 52 is entered. Wherein a target current I is preset₁Is 1A;

step 53: high-voltage direct-current bus switch K_iPAnd K_iNAre all disconnected; charging and discharging switch S_iPOr S_iNOne of the charge and discharge switches is closed, and the other one of the charge and discharge switches which is not closed keeps an open state;

step 54: judging the sampling voltage V of the voltage sampling module 2_iAnd a preset target voltage V_HIs taken as an absolute value (i.e., a first absolute value) to see whether it is not greater than a preset target value Δ V₂(i.e., the first preset target value), if yes, step 36 is entered, and if no, step 35 is entered. Wherein the target voltage V is preset_HIs the sampling voltage of the voltage sampling module 1, and a preset target value DeltaV₂Is 3V;

step 55: the bidirectional DC/DC power conversion module is switched to a boosting working mode, and the method specifically comprises the following steps:

the bidirectional DC/DC power conversion module takes electricity from the low-voltage energy storage device and converts the electricityThe voltage is subjected to boost conversion and then is output to the ith high-voltage direct current bus, so that the ith high-voltage direct current bus is in the process of being charged, and in the process, the voltage V output to the ith high-voltage direct current bus_iGradually rises to a preset target voltage V_HIn the process, the voltage V output to the ith high-voltage direct-current bus_iGradually rises to a preset target voltage V_HThe difference of (a) is smaller and smaller;

step 56: the bidirectional DC/DC power conversion module is switched to a stop working mode;

and 57: in step 53, the other unclosed charge and discharge switch is closed;

step 58: judging the sampling voltage V of the voltage sampling module 2_iAnd a preset target voltage V_LTaking the absolute value (i.e. the second absolute value) of the difference value to see whether the absolute value is not greater than the preset target value DeltaV₃(i.e., the second preset target value), if yes, step 60 is entered, and if no, step 59 is entered. Wherein a target voltage V is preset_LIs 60V, a preset target value DeltaV₃Is 3V;

step 59: the bidirectional DC/DC power conversion module is switched to a voltage reduction working mode, and the method specifically comprises the following steps:

Step 60: the bidirectional DC/DC power conversion module is switched to a stop working mode;

step 61: charging and discharging switch S_iPAnd S_iNIs disconnected.

In one embodiment, a method for charging a low-voltage energy storage device is provided, which is exemplified by a controller applied in the present application, and includes the following steps:

In a specific embodiment, the step of controlling the switch module to conduct the charge-discharge loop between the low-voltage energy storage device and the high-voltage direct-current bus includes:

Specifically, as shown in fig. 9, the control method for taking power from the high-voltage energy storage device to charge the low-voltage energy storage device may include the following steps:

step 71: the bidirectional DC/DC power conversion module is switched to a stop working mode;

step 72: charging and discharging switch S_iPAnd S_iNAre all closed except S_iPAnd S_iNThe other charge and discharge switches are turned off;

step 73: judging the sampling voltage V of the voltage sampling module 2_iAnd a preset target voltage V_HTaking an absolute value of the difference value to see whether the absolute value is not more than a preset target value delta V₁If yes, go to step 75, if no, go toStep 74; wherein the target voltage V is preset_HIs the sampling voltage of the voltage sampling module 1, and a preset target value DeltaV₁Is 3V;

step 74: the bidirectional DC/DC power conversion module is switched to a boosting working mode, and the method specifically comprises the following steps:

step 75: the bidirectional DC/DC power conversion module is switched to a stop working mode;

step 76: high-voltage direct-current bus switch K_iPAnd K_iNAre all closed;

step 77: the bidirectional DC/DC power conversion module is switched to a voltage reduction working mode, and the method specifically comprises the following steps:

and the bidirectional DC/DC power conversion module obtains electricity from the ith high-voltage direct-current bus, performs voltage reduction conversion on the voltage of the ith high-voltage direct-current bus, and outputs the voltage to the low-voltage energy storage device.

Specifically, as shown in fig. 10, the control method for taking power from the high-voltage energy storage device to charge the low-voltage energy storage device may include the following steps:

step 81: the bidirectional DC/DC power conversion module is switched to a stop working mode;

step 82: high-voltage direct-current bus switch K_iPOr K_iNOne of the high-voltage direct-current bus switches is closed, and the other high-voltage direct-current bus switch which is not closed is kept in an open state; charging and discharging switch S_iPAnd S_iNAre all closed except S_iPAnd S_iNThe other charge and discharge switches are turned off;

step 83: judging the sampling voltage V of the voltage sampling module 2_iAnd a preset target voltage V_HTaking an absolute value of the difference value to see whether the absolute value is not more than a preset target value delta V₁If yes, go to step 85, if no, go to step 84; wherein the target voltage V is preset_HIs the sampling voltage of the voltage sampling module 1, and a preset target value DeltaV₁Is 3V;

step 84: the bidirectional DC/DC power conversion module is switched to a boosting working mode, and the method specifically comprises the following steps:

step 85: the bidirectional DC/DC power conversion module is switched to a stop working mode;

step 86: in the step 82, the other unclosed high-voltage direct-current bus switch is closed;

step 87: the bidirectional DC/DC power conversion module is switched to a voltage reduction working mode, and the method specifically comprises the following steps:

In the high-voltage direct current bus energy control method (including the high-voltage direct current bus charging and discharging method and the low-voltage energy storage device charging method), based on the structure of the high-voltage direct current bus energy control system, the low-voltage energy storage device can be charged, a conventional unidirectional DC/DC power conversion module can be replaced to take electricity from the high-voltage energy storage device to charge the low-voltage energy storage device, and the integration level is further improved.

The application provides more reasonable switch actuation logic, and before ensuring actuation, the same reference voltage is provided, so that the risk of switch damage caused by excessive differential pressure in the instant of switch actuation is reduced.

Meanwhile, in the energy control method, more reasonable control logic is provided, namely before charging and discharging, the voltage difference value at two ends of the switch is judged, and if the voltage difference value is lower than a preset value, the charging and discharging action of the DCDC power conversion module is carried out, so that the situation that the DCDC power conversion module works frequently is avoided, and the charging and discharging speed can be improved in a specific scene.

More than, this application is before high-voltage bus precharge and predischarge, increase the high-voltage bus and carry out the secondary circuit voltage preconditioning mechanism in advance for the high-voltage bus, through voltage sampling module control precharge switch front and back pressure differential promptly, under the condition that pressure differential surpassed the threshold value, get the electricity from low pressure energy storage module through two-way DC power conversion module, adjust before and after precharge switch pressure differential is less than the threshold value, attract precharge switch again, under the condition that need not to increase outside cooling module or circuit stable components and parts, ensure that the high-voltage bus before bus switch actuation has the same reference voltage with for high-voltage bus charging circuit, improve high-voltage bus circuit's reliability.

It should be understood that although the various steps in the flowcharts of fig. 5-10 are shown in order as indicated by the arrows, the steps are not necessarily performed in order as indicated by the arrows. The steps are not performed in the exact order shown and described, and may be performed in other orders, unless explicitly stated otherwise. Moreover, at least some of the steps in fig. 5-10 may include multiple sub-steps or multiple stages that are not necessarily performed at the same time, but may be performed at different times, and the order of performance of the sub-steps or stages is not necessarily sequential, but may be performed in turn or alternating with other steps or at least some of the sub-steps or stages of other steps.

In one embodiment, there is provided a high voltage dc bus charging apparatus comprising:

the first on-off module is used for controlling the high-voltage direct current bus to correspond to a switch module in the bus control device and conducting a charge-discharge loop between the low-voltage energy storage device and the high-voltage direct current bus when the bidirectional DC/DC power conversion module is switched to a work stopping mode;

the processing module is used for acquiring the absolute value of the difference value of the sampling voltage of the second voltage sampling module and the sampling voltage of the first voltage sampling module; if the absolute value is larger than the preset target value, controlling the bidirectional DC/DC power conversion module to switch to a boosting working mode and charge the high-voltage direct-current bus until the absolute value is smaller than or equal to the preset target value;

and the second on-off module is used for controlling the bidirectional DC/DC power conversion module to switch to a work stopping mode if the absolute value is less than or equal to a preset target value, and controlling the switch module to disconnect a charge-discharge loop between the low-voltage energy storage device and the high-voltage direct current bus and switch on a high-voltage direct current bus loop between the high-voltage energy storage device and the high-voltage direct current bus.

In one embodiment, there is provided a high voltage dc bus discharging apparatus comprising:

the first on-off module is used for acquiring sampling current of the current sampling module in the bus control device when the bidirectional DC/DC power conversion module is switched to a work stopping mode; if the sampling current is less than or equal to the target current, controlling the switch module and disconnecting a high-voltage direct current bus circuit between the high-voltage energy storage device and the high-voltage direct current bus;

the second on-off module is used for acquiring a first absolute value of a difference value of the sampling voltage of the second voltage sampling module and the sampling voltage of the first voltage sampling module; if the first absolute value is larger than a first preset target value, controlling the bidirectional DC/DC power conversion module to switch to a boosting working mode and charge the high-voltage direct-current bus until the first absolute value is smaller than or equal to the first preset target value; if the first absolute value is smaller than or equal to the first preset target value, the bidirectional DC/DC power conversion module is controlled to be switched to a work stopping mode, and the switch module is controlled to conduct a charge-discharge loop between the low-voltage energy storage device and the high-voltage direct current bus;

the third on-off module is used for acquiring a second absolute value of the difference value between the sampling voltage of the second voltage sampling module and the target voltage; if the second absolute value is larger than a second preset target value, controlling the bidirectional DC/DC power conversion module to switch to a voltage reduction working mode, and performing voltage reduction conversion on the voltage of the high-voltage direct current bus until the second absolute value is smaller than or equal to the second preset target value; and if the second absolute value is less than or equal to the second preset target value, controlling the bidirectional DC/DC power conversion module to switch to a work stopping mode, and controlling the switch module to disconnect a charge-discharge loop between the low-voltage energy storage device and the high-voltage direct current bus.

In one embodiment, there is provided a low voltage energy storage charging device comprising:

the first on-off module is used for controlling the switch module to conduct a charge-discharge loop between the low-voltage energy storage device and the high-voltage direct-current bus when the bidirectional DC/DC power conversion module is switched to a work stopping mode;

the second on-off module is used for acquiring the absolute value of the difference value of the sampling voltage of the second voltage sampling module and the sampling voltage of the first voltage sampling module; if the absolute value is larger than the preset target value, controlling the bidirectional DC/DC power conversion module to switch to a boosting working mode and charge the high-voltage direct-current bus until the absolute value is smaller than or equal to the preset target value; and if the absolute value is less than or equal to the preset target value, the bidirectional DC/DC power conversion module is controlled to be switched to a stop working mode, the switch module is controlled to conduct a high-voltage direct-current bus circuit between the high-voltage energy storage device and the high-voltage direct-current bus, and the bidirectional DC/DC power conversion module is controlled to be switched to a step-down working mode to perform step-down conversion on the voltage of the high-voltage direct-current bus and transmit the voltage to the low-voltage energy storage.

For specific limitations of the charging and discharging device for the high-voltage direct current bus and the low-voltage energy storage charging device, reference may be made to the above limitations on the charging and discharging method for the high-voltage direct current bus and the charging method for the low-voltage energy storage device, which are not described herein again. The various modules in the above-described apparatus may be implemented in whole or in part by software, hardware, and combinations thereof. The modules can be embedded in a hardware form or independent from a processor in the computer device, and can also be stored in a memory in the computer device in a software form, so that the processor can call and execute operations corresponding to the modules.

In one embodiment, an automobile is provided, and the automobile comprises any one of the high-voltage direct current bus energy control systems.

In one particular example, the vehicle may be a new energy vehicle.

In one embodiment, a computer readable storage medium is provided, on which a computer program is stored, the computer program being executed by a processor to perform any one of the above-mentioned charging and discharging method for a high voltage dc bus and charging method for a low voltage energy storage device.

It will be understood by those skilled in the art that all or part of the processes of the methods of the embodiments described above can be implemented by hardware instructions of a computer program, which can be stored in a non-volatile computer-readable storage medium, and when executed, can include the processes of the embodiments of the methods described above. Any reference to memory, storage, database, or other medium used in the embodiments provided herein may include non-volatile and/or volatile memory, among others. Non-volatile memory can include read-only memory (ROM), Programmable ROM (PROM), Electrically Programmable ROM (EPROM), Electrically Erasable Programmable ROM (EEPROM), or flash memory. Volatile memory can include Random Access Memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in a variety of forms such as Static RAM (SRAM), Dynamic RAM (DRAM), Synchronous DRAM (SDRAM), Double Data Rate SDRAM (DDRSDRAM), Enhanced SDRAM (ESDRAM), Synchronous Link DRAM (SLDRAM), Rambus Direct RAM (RDRAM), direct bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM).

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only express several embodiments of the present application, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the concept of the present application, which falls within the scope of protection of the present application. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims

1. The high-voltage direct current bus energy control system is characterized by comprising a controller, a first voltage sampling module, a second voltage sampling module, a bidirectional DC/DC power conversion module and a plurality of bus control devices, wherein the first voltage sampling module, the second voltage sampling module, the bidirectional DC/DC power conversion module and the plurality of bus control devices are respectively connected with the controller; the bus control device is connected between the first voltage sampling module and the second voltage sampling module; the second voltage sampling module is connected with the bidirectional DC/DC power conversion module;

the first voltage sampling module is connected with the high-voltage energy storage device; the bidirectional DC/DC power conversion module is connected with a low-voltage energy storage device; each bus control device is respectively used for connecting a corresponding high-voltage direct-current bus interface; the bus control device comprises a switch module connected with the controller; the switch module is respectively connected with the first voltage sampling module, the second voltage sampling module and the high-voltage direct-current bus interface; the low-voltage energy storage device is used for supplying power to low-voltage electric parts of the automobile;

the controller is used for controlling the bidirectional DC/DC power conversion module to take electricity from or charge the low-voltage energy storage device according to the first voltage sampling module, the second voltage sampling module and sampling voltages before and after the switch module is switched on and off, so that charging and discharging of the high-voltage direct current bus are realized.

2. The HVDC bus energy control system of claim 1, wherein the bus control apparatus further comprises a current sampling module connected to the controller; the switch module comprises a high-voltage direct-current bus switch unit and a charge and discharge switch unit which are respectively connected with the controller;

when the high-voltage direct-current bus discharges, the controller monitors whether the sampling current of the current sampling module meets a preset condition or not, and when the sampling current meets the preset condition, the controller carries out corresponding on-off control on the high-voltage direct-current bus switch unit and the charge and discharge switch unit.

3. The high voltage direct current bus energy control system of claim 2,

the high-voltage direct current bus switch unit comprises a first high-voltage direct current bus switch and a second high-voltage direct current bus switch which are respectively connected with the controller; the charge and discharge switch unit comprises a first charge and discharge switch and a second charge and discharge switch which are respectively connected with the controller;

one end of the first high-voltage direct-current bus switch is connected with the first voltage sampling module through the current sampling module, and the other end of the first high-voltage direct-current bus switch is connected with the high-voltage direct-current bus interface and is connected with the second voltage sampling module through the first charge and discharge switch;

one end of the second high-voltage direct-current bus switch is connected with the first voltage sampling module through the current sampling module, and the other end of the second high-voltage direct-current bus switch is connected with the high-voltage direct-current bus interface and is connected with the second voltage sampling module through the second charge and discharge switch.

4. A method for charging a high voltage dc bus based on the energy control system of the high voltage dc bus of any of claims 1 to 3, comprising:

controlling the switch module to conduct a charge-discharge loop between the low-voltage energy storage device and the high-voltage direct-current bus;

acquiring an absolute value of a difference value of the sampling voltage of the second voltage sampling module and the sampling voltage of the first voltage sampling module;

if the absolute value is larger than a preset target value, controlling the bidirectional DC/DC power conversion module to switch to a boosting working mode and charge the high-voltage direct-current bus until the absolute value is smaller than or equal to the preset target value;

and if the absolute value is less than or equal to the preset target value, controlling the bidirectional DC/DC power conversion module to switch to a work stopping mode, and controlling the switch module to disconnect a charge-discharge loop between the low-voltage energy storage device and the high-voltage direct current bus and switch on a high-voltage direct current bus loop between the high-voltage energy storage device and the high-voltage direct current bus.

5. The method of charging a high voltage direct current bus according to claim 4,

the step of closing the switch module to conduct the charge-discharge loop between the low-voltage energy storage device and the high-voltage direct-current bus comprises the following steps:

closing a first charge-discharge switch and a second charge-discharge switch of the switch module; or the like, or, alternatively,

the method comprises the following steps of controlling the switch module to disconnect a charge-discharge loop between a low-voltage energy storage device and the high-voltage direct-current bus and switch on a high-voltage energy storage device and a high-voltage direct-current bus loop between the high-voltage direct-current buses, wherein the steps comprise:

6. A high voltage dc bus discharging method based on the high voltage dc bus energy control system of any of claims 1 to 3, comprising:

acquiring sampling current of a current sampling module in the bus control device; if the sampling current is less than or equal to the target current, controlling the switch module and disconnecting a high-voltage direct current bus circuit between the high-voltage energy storage device and the high-voltage direct current bus;

if the first absolute value is smaller than or equal to the first preset target value, controlling the bidirectional DC/DC power conversion module to switch to a stop working mode, and controlling the switch module to conduct a charge-discharge loop between the low-voltage energy storage device and the high-voltage direct-current bus;

and if the second absolute value is smaller than or equal to a second preset target value, controlling the bidirectional DC/DC power conversion module to switch to a stop working mode, and controlling the switch module to disconnect a charge-discharge loop between the low-voltage energy storage device and the high-voltage direct-current bus.

7. The high-voltage direct current bus discharging method according to claim 6, wherein if the sampled current is less than or equal to a target current, the step of controlling the switch module and disconnecting the high-voltage direct current bus loop between the high-voltage energy storage device and the high-voltage direct current bus comprises:

disconnecting a first high-voltage direct-current bus switch and a second high-voltage direct-current bus switch in the switch module; closing any one of a first charge-discharge switch and a second charge-discharge switch of the switch module;

the step of controlling the switch module to disconnect the charge-discharge loop comprises the following steps:

8. A low-voltage energy storage device charging method based on the high-voltage direct current bus energy control system of any one of claims 1 to 3 is characterized by comprising the following steps:

and if the absolute value is less than or equal to a preset target value, controlling the bidirectional DC/DC power conversion module to switch to a stop working mode, controlling the switch module to conduct a high-voltage direct-current bus circuit between the high-voltage energy storage device and the high-voltage direct-current bus, and controlling the bidirectional DC/DC power conversion module to switch to a voltage reduction working mode so as to perform voltage reduction conversion on the voltage of the high-voltage direct-current bus and transmit the voltage to the low-voltage energy storage device.

9. The method of charging a low voltage energy storage device of claim 8,

controlling the switch module to conduct a charge-discharge loop between the low-voltage energy storage device and the high-voltage direct-current bus, and the method comprises the following steps:

the step of controlling the switch module to conduct a high-voltage direct current bus loop between the high-voltage energy storage device and the high-voltage direct current bus comprises the following steps:

10. An automobile, characterized by comprising the high voltage direct current bus energy control system of any one of claims 1 to 3.