CN116418080A

CN116418080A - Power supply control method, power conversion device, energy storage device and storage medium

Info

Publication number: CN116418080A
Application number: CN202310337013.7A
Authority: CN
Inventors: 王亚雄; 吴东; 陈熙; 王雷
Original assignee: Ecoflow Technology Ltd
Current assignee: Ecoflow Technology Ltd
Priority date: 2023-03-30
Filing date: 2023-03-30
Publication date: 2023-07-11

Abstract

The application is applicable to the technical field of energy storage, and provides a power supply control method, a power conversion device, energy storage equipment and a storage medium, wherein the method comprises the following steps: determining a battery module to be started and a battery module to be closed according to the starting state and the battery voltage of each connected battery module; obtaining a second target current according to the first target current currently output by the AC/DC conversion circuit, the required current of the battery module to be started and the required current of the battery module to be shut down; generating a first drive signal to an AC/DC conversion circuit; when the actual output current of the conversion circuit is matched with the second target current, the battery module to be closed is controlled to be closed, and the battery module to be opened is controlled to be opened. In the application, when the actual output current of the AC/DC conversion circuit is matched with the second target current, the switching operation of the battery module is performed, so that the condition that the load cannot work normally due to power failure in the switching process of the battery module can be avoided.

Description

Power supply control method, power conversion device, energy storage device and storage medium

Technical Field

The application belongs to the technical field of energy storage, and particularly relates to a power supply control method, a power conversion device, energy storage equipment and a storage medium.

Background

The energy storage device generally stores electric energy through the battery module, and releases the electric energy stored in the battery module when the energy storage device is needed. In practical application, a plurality of battery modules can be connected to the energy storage device to improve the battery capacity of the energy storage device. When the energy storage device is externally connected with a load and/or a power supply, the power supply supplies power to the battery module and a direct current load connected to the direct current bus through the inverter circuit.

In the related art, when the energy storage device is externally connected with a direct current load and a power supply, the power supply supplies power to the battery modules and the direct current load through the inverter circuit, if a plurality of battery modules need to be switched, namely, the battery modules are charged and switched from the battery module A to the battery module B for charging, in the process of switching the battery modules, if the power supply is powered off, the problem that the direct current load is closed due to no power supply easily occurs, and the use of a user is affected.

Disclosure of Invention

The embodiment of the application provides a power supply control method, a power conversion device, energy storage equipment and a storage medium, which can solve the problem that in the related art, when a battery module is switched, if a power supply is powered down, a direct current load is easily turned off due to no power supply, and the use of a user is affected.

A first aspect of an embodiment of the present application provides a power supply control method applied to a power conversion device; the power conversion device comprises an AC/DC conversion circuit and a DC/DC conversion circuit; the first end of the AC/DC conversion circuit is used for being connected with a power supply, and the second end of the AC/DC conversion circuit is connected with the first end of the DC/DC conversion circuit through a direct current bus; the direct current bus is also used for being connected with a direct current load; the second end of the DC/DC conversion circuit is used for being connected with at least one battery module; the method comprises the following steps:

when detecting that a direct current load and a power supply are externally connected, determining a battery module to be started and a battery module to be closed according to the starting state of each connected battery module and the battery voltage of each battery module;

obtaining a second target current of the AC/DC conversion circuit according to a first target current currently output to the DC bus by the AC/DC conversion circuit, a required current of a battery module to be started and a required current of the battery module to be shut down;

generating a first driving signal to the AC/DC conversion circuit according to the second target current, wherein the first driving signal is used for driving the AC/DC conversion circuit to output the second target current;

when the actual output current output by the AC/DC conversion circuit to the DC bus is matched with the second target current, the battery module to be closed is controlled to be closed, and the battery module to be opened is controlled to be opened.

A second aspect of the embodiments of the present application provides a power conversion apparatus, including a controller, an AC/DC conversion circuit, and a DC/DC conversion circuit; the first end of the AC/DC conversion circuit is used for being connected with a power supply, and the second end of the AC/DC conversion circuit is connected with the first end of the DC/DC conversion circuit through a direct current bus; the direct current bus is also used for being connected with a direct current load; the second end of the DC/DC conversion circuit is used for being connected with at least one battery module; the controller is configured to perform the steps of the power supply control method provided in the first aspect.

A third aspect of the embodiments of the present application provides an energy storage device, including a battery module, a power conversion device, a memory, a processor, and a computer program stored in the memory and executable on the processor, where the processor implements the steps of the power supply control method provided in the first aspect when executing the computer program.

A fourth aspect of the embodiments of the present application provides a computer-readable storage medium storing a computer program, which when executed by a processor, implements the steps of the power supply control method provided in the first aspect.

According to the power supply control method, the battery modules to be started and the battery modules to be shut down are determined through the starting states of the battery modules and the battery voltages, and the second target current of the AC/DC conversion circuit is obtained based on the first target current output to the DC bus by the AC/DC conversion circuit and the required current of the battery modules to be started and the battery modules to be shut down, and when the actual output current of the AC/DC conversion circuit is matched with the second target current, the switching operation of the battery modules is executed, so that the situation that the DC load cannot work normally due to power failure in the switching process of the battery modules can be avoided.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following description will briefly introduce the drawings that are needed in the embodiments or the related technical descriptions, and it is obvious that the drawings in the following description are only some embodiments of the present application, and other drawings may be obtained according to these drawings without inventive effort for a person of ordinary skill in the art.

FIG. 1 is a system architecture diagram of an application of a power control method according to an embodiment of the present application;

FIG. 2 is a flow chart of a power supply control method according to an embodiment of the present application;

fig. 3 is a flowchart of determining a battery module to be turned on and a battery module to be turned off according to an embodiment of the present application;

FIG. 4 is a flow chart of a power supply control method provided in another embodiment of the present application;

FIG. 5 is a flow chart of a power supply control method provided by a further embodiment of the present application;

FIG. 6 is a flow chart of a power supply control method provided in yet another embodiment of the present application;

FIG. 7 is a use scenario diagram of a power control method according to an embodiment of the present application;

FIG. 8 is a block diagram of a power conversion apparatus according to an embodiment of the present application;

fig. 9 is a block diagram of a power conversion apparatus according to another embodiment of the present application;

FIG. 10 is a block diagram of one embodiment of the present application is a block diagram of the energy storage device.

Detailed Description

In the following description, for purposes of explanation and not limitation, specific details are set forth, such as particular system configurations, techniques, etc. in order to provide a thorough understanding of the embodiments of the present application. It will be apparent, however, to one skilled in the art that the present application may be practiced in other embodiments that depart from these specific details. In other instances, detailed descriptions of well-known systems, devices, circuits, and methods are omitted so as not to obscure the description of the present application with unnecessary detail.

It should be understood that the terms "comprises" and/or "comprising," when used in this specification and the appended claims, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

As used in this specification and the appended claims, the term "if" may be interpreted as "when..once" or "in response to a determination" or "in response to detection" depending on the context. Similarly, the phrase "if a determination" or "if a [ described condition or event ] is detected" may be interpreted in the context of meaning "upon determination" or "in response to determination" or "upon detection of a [ described condition or event ]" or "in response to detection of a [ described condition or event ]".

Reference in the specification to "one embodiment" or "some embodiments" or the like means that a particular feature, structure, or characteristic described in connection with the embodiment is included in one or more embodiments of the application. Thus, appearances of the phrases "in one embodiment," "in some embodiments," "in other embodiments," and the like in the specification are not necessarily all referring to the same embodiment, but mean "one or more but not all embodiments" unless expressly specified otherwise. The terms "comprising," "including," "having," and variations thereof mean "including but not limited to," unless expressly specified otherwise.

In order to explain the technical aspects of the present application, the following examples are presented.

Referring to fig. 1, fig. 1 is a system architecture diagram to which a power supply control method according to an embodiment of the present application is applied. The power supply control method provided by the present embodiment corresponds to the power conversion apparatus 103. As shown in fig. 1, the power conversion device 103 may include an AC/DC conversion circuit 1031 and a DC/DC conversion circuit 1032.

A first end of the AC/DC conversion circuit 1031 is used for being connected with the power supply 102, and a second end of the AC/DC conversion circuit 1031 is connected with a first end of the DC/DC conversion circuit 1032 through a direct current bus; the direct current bus is also connected with a direct current load 101; a second terminal of the DC/DC conversion circuit 1032 is connected to the first battery module 104 and the second battery module 105. The AC load 106 is also connected to a first terminal of the AC/DC conversion circuit 1031. The dc load 101 is a device that receives dc power. Ac load 106 is a device that receives ac power. The power supply 102 in this embodiment is an AC power supply, and the input AC power can directly supply power to the AC load 106, or can supply power to the DC load 101 after AC/DC conversion by the AC/DC conversion circuit in the power conversion device 103, or can supply power to each battery module, such as the first battery module 104 and the second battery module 105, after voltage increase and decrease by the DC/DC conversion circuit. The number of the battery modules may be single or two or more.

In some application scenarios, the power conversion device 103 may be detachably connected to the battery modules, where the power conversion device 103, the first battery module 104, and the second battery module 105 are used as separate components. In other application scenarios, the power conversion device 103 may also be integrated with the first battery module 104 as an energy storage device. And the energy storage equipment is provided with a parallel operation port for connecting other battery modules with the battery modules in the energy storage equipment.

When detecting that the direct current load 101 and the power supply 102 are externally connected, the power conversion device 103 determines a battery module to be started and a battery module to be shut down according to the starting state of each connected battery module and the battery voltage of each battery module; obtaining a second target current of the AC/DC conversion circuit 1031 according to a first target current currently output to the DC bus by the AC/DC conversion circuit 1031, a required current of the battery module to be turned on, and a required current of the battery module to be turned off; generating a first drive signal to the AC/DC conversion circuit 1031 according to the second target current, wherein the first drive signal is used to drive the AC/DC conversion circuit 1031 to output the second target current; when the actual output current output by the AC/DC conversion circuit 1031 to the DC bus is matched with the second target current, the battery module to be turned off is controlled to be turned on, and the battery module to be turned on is controlled to be turned on. When the actual output current output by the conversion circuit is matched with the second target current, the switching operation of the battery module is performed, and the condition that the load cannot work normally due to power failure in the switching process of the battery module can be avoided.

It should be noted that, the power supply control method provided in the embodiment of the present application is performed by the power conversion device 103, and may specifically be performed by a controller in the power conversion device 103.

It should be understood that the numbers of the dc loads 101, the power supply 102, the power conversion device 103, the first battery module 104, and the second battery module 105 in fig. 1 are merely illustrative. There may be any number of power supplies 102, power conversion devices 103, first battery modules 104, and second battery modules 105, as needed for implementation.

Referring to fig. 2, fig. 2 is a flowchart of a power supply control method according to an embodiment of the present application, and the flowchart may include the following steps 201 to 204.

Step 201, when detecting that a direct current load and a power supply are externally connected, determining a battery module to be turned on and a battery module to be turned off according to the starting state of each connected battery module and the battery voltage of each battery module.

Wherein the enabling state includes an on state and an off state. When the battery module is in an on state, the battery module can charge through the electric energy converted by the power conversion device or supply power to the power conversion device. When the battery module is in a closed state, the battery module is not charged or discharged.

The battery voltage is the voltage between the anode and the cathode of the battery module, namely the voltage output by the battery module.

The battery module to be turned on is usually a battery module to be turned on, and the battery module to be turned off is usually a battery module to be turned off.

The power conversion device may be provided with an interface for connecting a dc load, an interface for connecting a power supply, and an interface for connecting a battery module. The power conversion device can detect whether a direct current load is externally connected by detecting the current at the direct current load interface or confirm whether the direct current load is externally connected by judging whether a hardware in-place signal is received at the direct current load interface. The power conversion device can also detect whether a power supply is externally connected by detecting the current at the power supply interface, detect the starting state of the battery module by detecting the current at the battery module interface or directly detect the starting state of the battery module by acquiring the states of a charging switch tube and a discharging switch tube in the battery module. Of course, the power conversion device may also directly read the activation state identifier of the battery module to determine the activation state of the battery module, for example, when the activation state identifier is a first value, the battery module is confirmed to be in an on state, or else, the battery module is confirmed to be in an off state. Specifically, when the power conversion device detects current at the direct current load interface, it can be determined that the power conversion device is externally connected with a direct current load; when the power conversion device detects current at the power supply interface, it can be determined that the power conversion device is externally connected with a power supply; when the power conversion device detects current at the battery module interface, the connected battery module can be determined to be in an on state, and when the power conversion device does not detect current at the battery module interface, the connected battery module can be determined to be in an off state.

A battery management module (Battery Management System, BMS) for managing battery charging is generally included in the battery module, and the BMS may perform voltage detection on the battery module and then transmit the detected battery voltage to the power conversion device.

The power conversion device can obtain the battery voltage of each battery module through communication with the BMS. At this time, it is necessary to determine whether parallel charging is necessary or to switch the battery pack for charging in combination with the activation state of the battery module.

Specifically, when the current battery modules are in the closed state, determining whether the voltage deviation between the battery voltages is smaller than a preset deviation threshold according to the battery voltages of the battery modules, if so, determining the battery modules with the voltage deviation within the preset deviation threshold as the battery modules to be turned on, and keeping the other battery modules in the closed state. And if the voltage deviation among the current battery voltages is larger than a preset deviation threshold value, determining the battery module with the lowest battery voltage as the battery module to be started, and keeping other battery modules in a closed state.

When the battery module in the open state exists, the parallel voltage range is determined according to the battery module in the open state, and if the battery voltage of the battery module in the closed state exists in the parallel voltage range, the battery module is determined to be the battery module to be opened. If the battery voltage of the battery module in the open state is no longer within the parallel voltage range, the battery module is determined to be closed. And when the battery voltage of the battery module in the closed state is not in the parallel voltage electric power range and the absolute value of the deviation between the battery voltage of the battery module in the open state and the battery voltage of the battery module is larger than a preset value, determining the battery module as the battery module to be opened, and determining all the battery modules in the open state as the battery module to be closed.

The above-mentioned process of determining the battery module to be turned on and the battery module to be turned off is essentially to determine whether parallel charging between the battery modules is possible or whether cutting charging is required, and other determination logic in the art may be adopted.

Step 202, obtaining a second target current of the AC/DC conversion circuit according to a first target current currently output to the DC bus by the AC/DC conversion circuit, a required current of the battery module to be turned on, and a required current of the battery module to be turned off.

The required current is usually the charging current required by the corresponding battery module during charging. The required current for the battery module to be turned on is usually the charging current required when the battery module to be turned on is charged. The required current for the battery module to be turned off is usually the charging current required for charging the battery module to be turned off.

The power conversion device can obtain switching current deviation between the battery module to be started and the battery module to be closed through the required current of the battery module to be started and the required current of the battery module to be closed, and then the switching current deviation is adopted to update the first target current of the AC/DC conversion circuit, so that the second target current output by the AC/DC conversion circuit after the battery module is switched is obtained. Here, the switching current deviation is a deviation of the required current before and after the switching of the battery module. For example, the first target current of the AC/DC conversion circuit is 10A, the required current of the battery module to be turned on is 6A, the required current of the battery module to be turned off is 4A, the switching current deviation may be obtained as 2A, and at this time, the second target current of the AC/DC conversion circuit after the battery module is switched may be obtained as 12A by using the switching current deviation 2A.

Step 203, generating a first driving signal to the AC/DC conversion circuit according to the second target current.

The first driving signal is used for driving the AC/DC conversion circuit to output a second target current.

The power conversion device may generate the first driving signal after obtaining the second target current, and then transmit the generated first driving signal to the AC/DC conversion circuit, thereby controlling the AC/DC conversion circuit to output the second target current.

And 204, when the actual output current output by the AC/DC conversion circuit to the DC bus is matched with the second target current, controlling the battery module to be closed and controlling the battery module to be opened.

The power conversion device can detect the actual output current output to the direct current bus by the AC/DC conversion circuit, and compare the detected actual output current with the second target current to obtain the current deviation between the actual output current and the second target current. When the current deviation is smaller than or equal to a preset current deviation threshold value, it can be determined that the actual output current output by the AC/DC conversion circuit to the direct current bus is matched with the second target current. In addition, when the current deviation between the actual output current and the second target current is greater than the preset current deviation threshold, it may be determined that the actual output current output by the AC/DC conversion circuit to the DC bus is not adapted to the second target current. Here, the preset current deviation threshold is generally a threshold of a preset current deviation. For example, 0.5A.

When the actual output current outputted from the AC/DC conversion circuit to the DC bus is matched with the second target current, a switching operation of the battery module may be performed. At this time, the power conversion device can send a closing instruction to the BMS of the battery module to be closed, control the battery module to be closed to close and charge, send an opening instruction to the battery module to be opened, and control the battery module to be opened to open and charge.

In some embodiments, the power conversion device may also update the target voltage output by the AC/DC conversion circuit. As an example, the power conversion device may obtain a required voltage of the battery module to be turned on through the BMS of the battery module to be turned on, and obtain a required voltage of the load. The power conversion device takes the required voltage of a load as the load target voltage of the AC/DC conversion circuit, takes the required voltage of the battery module as the battery target voltage of the DC/DC conversion circuit, further controls the AD/DC conversion circuit according to the load target voltage of the AC/DC conversion circuit and the power supply voltage of the power supply source so as to enable the AD/DC conversion circuit to output the load target voltage, and controls the DC/DC conversion circuit according to the output voltage of the AC/DC conversion circuit and the battery target voltage so as to enable the DC/DC conversion circuit to output the battery target voltage.

According to the power supply control method provided by the embodiment, the battery modules to be started and the battery modules to be shut down are determined according to the starting state and the battery voltage of each battery module, and the second target current of the AC/DC conversion circuit is obtained based on the first target current currently output to the DC bus, the battery modules to be started and the required current of the battery modules to be shut down, and when the actual output current output by the AC/DC conversion circuit is matched with the second target current, the switching operation of the battery modules is executed, so that the situation that the load caused by power failure cannot work normally in the switching process of the battery modules can be avoided.

In the related art, when the battery modules are switched to charge, for example, when the first battery module 104 needs to be switched to the second battery module 105 to supply power, the charging switch tube and the discharging switch tube in the first battery module 104 are turned off, and then the charging switch tube and the discharging switch tube in the second battery module 105 needing to be charged are turned on, in this process, a short neutral period occurs, and the first battery module 104 and the second battery module 105 are both turned off, once the power supply 102 is powered down, the problem that the load has no power supply and is powered down and turned off occurs at the moment, and the load cannot work any more, thereby affecting the use of users. In this embodiment, before the battery module is switched, the AC/DC conversion circuit in the power conversion device 103 is controlled according to the second target current after switching, so that when the actual output current of the AC/DC conversion circuit is ensured to be matched with the second target current after switching (that is, the magnitude is within the allowable deviation range), the switching operation of the battery module is performed, so that the actual output of the AC/DC conversion circuit can meet the load power supply requirement in the cutting process and the power supply requirement of the battery module after cutting, and the problem that the load cannot be normally supplied due to the power failure of the power supply or the increase of the required current of the battery module after switching does not occur, and the charging efficiency and the stability of the charging on-load cutting machine are improved.

Referring to fig. 3, fig. 3 is a flowchart for determining a battery module to be turned on and a battery module to be turned off according to an embodiment of the present application, and the flowchart may include the following steps 301 to 303.

Step 301, determining and powering the voltage range according to the battery voltage of the activated battery module in each battery module.

The parallel operation voltage range is generally a range of voltages of the battery modules that can be used in parallel operation. The combined voltage range is typically a range consisting of a combined voltage upper limit and a combined voltage lower limit. Here, the parallel voltage upper limit is a voltage maximum value corresponding to the parallel voltage range, and the parallel voltage lower limit is a voltage minimum value corresponding to the parallel voltage range.

The power conversion device may determine and power the voltage range in a number of ways.

As one example, the power conversion device may determine the parallel machine voltage range using a target battery module among the activated battery modules and a preset parallel machine deviation. Here, the target battery module may be the battery module with the highest corresponding voltage in the activated battery modules, the battery module with the lowest corresponding voltage in the activated battery modules, or the battery module selected randomly from the activated battery modules. The preset parallel operation deviation is usually a deviation of preset parallel operation voltage, and the preset parallel operation deviation can comprise an on-parallel operation deviation and an off-parallel operation deviation. For example, if the battery module with the highest corresponding voltage of the enabled battery modules is taken as the target battery module, the battery voltage of the battery module with the highest corresponding voltage of the enabled battery modules is 10V, the onboard deviation is +0.5v, the off-board deviation is-0.5V, and the power conversion device can determine that the voltage range is 9.5V to 10.5V.

As another example, the power conversion device may determine the parallel voltage electric power range by taking the battery voltage of the battery module having the highest corresponding voltage among the activated battery modules as the upper limit of the parallel voltage electric power range and the battery voltage of the battery module having the lowest corresponding voltage among the activated battery modules as the lower limit of the parallel voltage electric power range. For example, if the battery voltage of the battery module with the highest voltage among the activated battery modules is 10V and the battery voltage of the battery module with the lowest voltage is 9V, the power conversion device may determine that the combined voltage is in the range of 9V to 10V. It will be appreciated that the manner in which the voltage range is determined and is not limited to that mentioned above, but may be determined in other ways known in the art.

In step 302, if there is a battery voltage of the non-activated battery module lower than the preset voltage threshold and the battery voltage is not within the parallel voltage range, determining the non-activated battery module as a battery module to be activated, and determining all activated battery modules as battery modules to be deactivated.

The preset voltage threshold is usually a preset voltage value. When the battery voltage of the battery module is lower than the preset voltage threshold, the battery module is low in electric quantity, and the battery module needs to be charged.

The power conversion device may compare the battery voltage of the non-activated battery module with a preset voltage threshold, and a combined voltage upper limit and a combined voltage lower limit of the combined voltage range, respectively. If the battery voltage of the non-activated battery module is lower than the preset voltage threshold and the battery voltage is not within the parallel voltage range, the electric quantity of the non-activated battery module is relatively low, the non-activated battery module needs to be charged, and the non-activated battery module and the activated battery module cannot be charged in parallel. At this time, the power conversion device may determine the inactive battery module as a battery module to be turned on, and determine all the activated battery modules as battery modules to be turned off.

And step 303, if the battery voltage of the non-activated battery module is within the parallel voltage range, determining the non-activated battery module as the battery module to be started.

If there is a battery voltage of the non-activated battery module within the parallel voltage range, indicating that the voltage difference between the non-activated battery module and the activated battery module is small, the non-activated battery module may be charged in parallel with the activated battery module. At this time, the power conversion device may determine the inactive battery module as the battery module to be turned on.

It will be appreciated that step 303 and step 302 are two cases in parallel, and it is determined whether step 303 or step 302 needs to be performed according to the actual situation.

According to the power supply control method provided by the embodiment, the parallel voltage range is determined through the battery voltage of the started battery module, whether the non-started battery module can be subjected to parallel charging with the started battery module or not is determined based on the parallel voltage range, the quick and accurate determination of the battery module to be started and the battery module to be closed can be realized, and the efficiency of determining the battery module to be started and the battery module to be closed can be improved.

Referring to fig. 4, fig. 4 is a flowchart of a power supply control method according to another embodiment of the present application, and the flowchart may include the following steps 401 to 402.

Step 401, outputting a disable signal to the DC/DC conversion circuit to control the DC/DC conversion circuit to stop operating.

The disable signal is typically a signal for instructing the DC/DC converter circuit to stop operating.

When the power supply supplies power to the battery module, the power supply generally needs to convert electric energy through a DC/DC conversion circuit in the power conversion device, and then the converted electric energy is transmitted to the battery module. A bus capacitor is usually arranged between the AC/DC conversion circuit and the DC/DC conversion circuit, and when the battery module needs to be switched, the power conversion device can output a disable signal to the DC/DC conversion circuit first to control the DC/DC conversion circuit to stop working, so that the electric energy provided by the power supply is stored in the bus capacitor.

Step 402, after the battery module to be turned on is turned on, an enabling signal is output to the DC/DC conversion circuit to enable the DC/DC conversion circuit to operate.

The enable signal is typically a signal for indicating start of operation.

After the battery module to be started is started, the battery module is indicated to finish switching operation, the power conversion device needs to restart the DC/DC conversion circuit, so that electric energy provided by the power supply is converted by the DC/DC conversion circuit and then is transmitted to the battery module to charge the battery module.

Here, in the process from stopping the operation to restarting the operation of the DC/DC conversion circuit, the electric energy stored in the bus capacitor is used to supply power to the DC load, so as to ensure the use requirement of the DC load.

According to the power supply control method provided by the embodiment, the DC/DC conversion circuit is controlled to stop working, so that no power supply is used for supplying power to the battery module in the switching process, the safety of the switching machine is improved, at the moment, the power supply charges the bus capacitor through the AC/DC conversion circuit, after the battery module to be started is started, the DC/DC conversion circuit is controlled to work, stable electric energy can be provided for the direct-current load through the bus capacitor in the switching process of the battery module, and the power utilization stability of the direct-current load is guaranteed.

In other embodiments, the AC/DC conversion circuit may be disabled after ensuring that the output of the AC/DC conversion circuit matches the second target current, so as to be turned on after switching between the battery modules is completed. And in the switching process, the bus capacitor on the direct current bus is used for maintaining the power supply of the direct current load.

In some embodiments, the obtaining the second target current of the AC/DC conversion circuit according to the first target current currently output to the DC bus by the AC/DC conversion circuit, the required current of the battery module to be turned on, and the required current of the battery module to be turned off may include: and adding the first target current currently output to the direct current bus by the AC/DC conversion circuit to the required current of the battery module to be started to obtain a current sum, and subtracting the required current of the battery module to be closed from the current sum to obtain a second target current.

When determining the second target current of the AC/DC conversion circuit, the power conversion device may add the required current of the battery module to be turned on to obtain a current sum, and subtract the required current of the battery module to be turned off to obtain the second target current on the basis of the first target current currently output by the AC/DC conversion circuit. For example, if the first target current currently output by the AC/DC conversion circuit is 10A, the required current of the battery module to be turned on is 6A, and the required current of the battery module to be turned off is 4A, the power conversion device may add 6A to 10A to obtain a current sum of 16A, and subtract 4A to obtain a second target current of 12A.

The power conversion device can firstly subtract the required current of the battery module to be closed to obtain a current difference on the basis of the first target current currently output by the AC/DC conversion circuit, and then add the required current of the battery module to be opened to obtain a second target current. For example, if the first target current currently output by the AC/DC conversion circuit is 10A, the required current of the battery module to be turned on is 6A, and the required current of the battery module to be turned off is 4A, the power conversion device may first subtract 4A from 10A to obtain a current difference of 6A, and then add 6A to obtain a second target current of 12A.

In this embodiment, the current sum is obtained by the first target current currently output by the AC/DC conversion circuit and the required current of the battery module to be turned on, and then the second target current is obtained by adopting the required current and the current sum of the battery module to be turned off, so that the second target current can be quickly determined, so that the power conversion module can generate a corresponding driving signal based on the second target current, and further the switching efficiency of the battery module is improved.

Referring to fig. 5, fig. 5 is a flowchart of a power supply control method according to another embodiment of the present application, and the flowchart may include the following steps 501 to 502.

And step 501, controlling the battery module to be closed.

When the actual output current output to the direct current bus by the AC/DC conversion circuit is matched with the second target current, the power conversion module can send a closing instruction to the BMS of the battery module to be closed, and the battery module to be closed is controlled to be closed for charging.

Step 502, after confirming that the battery module to be turned off is turned off, controlling the battery module to be turned on.

In the process of switching the battery module, the power replacement device can detect the current at the interface of the battery module to be closed, and when the current at the interface of the battery module to be closed is lower than the connection current threshold value, the battery module to be closed is confirmed to be closed. The power device is connected with the battery module to be closed through the battery module interface to be closed. In one embodiment, the connection current threshold may be set to 0A.

If the battery module needs to be switched, the battery voltage of the battery module to be switched off (the battery module in the on state before the switching) is higher than the battery voltage of the battery module to be switched on (the battery module in the off state before the switching), and the voltage difference between the battery module to be switched on and the battery module to be switched off is usually larger than a preset voltage difference threshold, and the battery module to be switched on and the battery module to be switched off cannot be charged in parallel. In the process of switching the battery modules, if the battery module to be closed is not closed and the battery module to be opened is opened, the battery module to be closed supplies power to the battery module to be opened, and the battery module to be opened is easy to damage.

The power conversion device can send a closing instruction to the BMS of the battery module to be opened after confirming that the battery module to be closed is closed, and control the battery module to be opened.

According to the power supply control method provided by the embodiment, the battery module to be closed is controlled to be closed firstly, and after the battery module to be closed is confirmed to be closed, the battery module to be opened is controlled to be opened, so that the situation that the battery module to be closed is not closed and the battery module to be opened is opened, and the battery module to be closed supplies power to the battery module to be opened, and the situation that the battery module to be opened is damaged is avoided, and the safety of switching the battery modules can be improved.

Referring to fig. 6, fig. 6 is a flowchart of a power supply control method according to another embodiment of the present application, and the flowchart may include the following steps 601 to 602.

And step 601, closing a charging switch tube and a discharging switch tube of the battery module to be closed.

The charging switch tube is a switch for controlling the charge on and charge off. The charging switch tube can be a charging MOS tube, the charging MOS tube can be a charging NMOS tube with high-level signal conduction and low-level signal closing, and can also be a charging PMOS tube with low-level signal conduction and high-level signal closing.

The discharge switching tube is a switch for controlling the discharge to be turned on and off. The discharge switch tube can be a discharge MOS tube, the discharge MOS tube can be a discharge NMOS tube with high-level signal conduction and low-level signal closing, and can also be a discharge PMOS tube with low-level signal conduction and high-level signal closing.

Here, each battery module may include a battery cell module, a charge switching tube, and a discharge switching tube, and the power conversion device may transmit a shutdown instruction to the BMS of the battery module to be shutdown, and control the BMS of the battery module to be shutdown to shutdown the charge switching tube and the discharge switching tube of the battery module to be shutdown.

Step 602, after confirming that the charging switch tube and the discharging switch tube of the battery module to be turned off are both turned off, turning on the charging switch tube and the discharging switch tube of the battery module to be turned on.

The power conversion device can detect the current at the interface of the battery module to be closed, and when the current at the interface of the battery module to be closed is lower than the connection current threshold, the charging switch tube and the discharging switch tube of the battery module to be closed are confirmed to be turned off. And then, the power conversion device can send an opening instruction to the BMS of the battery module to be opened, and the BMS of the battery module to be opened is controlled to open a charging switch tube and a discharging switch tube of the battery module to be opened.

According to the power supply control method provided by the embodiment, the on-off tube of the charging switch tube and the discharging switch is controlled through the voltage signal, so that the battery module can be quickly turned on and off, and the switching efficiency of the battery module is improved.

In some embodiments, the power supply control method may further include: if the deviation between the second target current and the actual output current output to the direct current bus by the AC/DC conversion circuit is larger than a preset current threshold value within the preset waiting time for outputting the first driving signal, generating fault alarm information.

The preset waiting time period is usually a preset waiting time period, for example, 200ms.

The preset current threshold is usually a preset current value, for example, 0.1A.

The fault alarm information is usually information for alarming a fault. The implementation forms of the fault warning information can include a voice form, a text form, a video form and the like.

The power conversion device may start timing when the first driving signal is output, and after a preset waiting period, the power conversion device may detect an actual output current output by the AC/DC conversion circuit to the DC bus, and then compare the detected actual output current with the second target current. If the deviation between the second target current and the actual output current is larger than the preset current threshold value, the output of the AC/DC conversion circuit is not synchronous with the first driving signal and has a fault, so that the power conversion device can generate fault alarm information to prompt a user that the power conversion device has a fault. For example, if the preset waiting time is 200ms, the second target current is 10A, the preset current threshold is 0.1A, the power conversion device starts to count when outputting the first driving signal, after 200ms, it is detected that the actual output current of the AC/DC conversion circuit output to the DC bus is 9.5A, the deviation between the second target current and the actual output current is 0.5A, and is greater than the preset current threshold, the power conversion device can generate fault alarm information in voice form to inform the user that the power conversion device has a fault.

According to the power supply control method provided by the embodiment, when the actual output current of the AC/DC conversion circuit is not matched with the second target current within the preset waiting time, the fault alarm information for prompting the user that the power conversion device has faults is generated, so that the user can find the faults in time and accordingly make corresponding solving measures.

The present application also provides an energy storage device, as shown in fig. 7. The energy storage device 107 comprises a power conversion means 103 and a first battery module 104. The second battery module 105 is connected to one end of the DC/DC conversion circuit 1032 through a parallel port (not shown) on the energy storage device 107. The power conversion device 103 includes an AC/DC conversion circuit 1031, a DC/DC conversion circuit 1032, and a controller 1033, a first terminal of the AC/DC conversion circuit 1031 is used for connecting to the power supply 102, and a second terminal of the AC/DC conversion circuit 1031 is connected to the first terminal of the DC/DC conversion circuit 1032 through a DC bus; a BUS capacitor C is arranged on the direct current BUS (between BUS+ and BUS), and the direct current BUS is also connected with a direct current load 101; a second terminal of the DC/DC conversion circuit 1032 is connected to the first battery module 104 and the second battery module 105, and the AC/DC conversion circuit 1031 and the DC/DC conversion circuit 1032 are connected to the controller 1033, respectively. The first battery module 104 includes a first battery cell module 1043, a first charge switching tube 1041, and a first discharge switching tube 1042. The first charge switching tube 1041 and the first discharge switching tube 1042 are sequentially connected between the first cell module 1043 and the second end of the DC/DC conversion circuit 1032, for controlling the charge and discharge of the first cell module 1043. The second battery module 105 includes a second battery cell module 1053, a second charge switching tube 1051, and a second discharge switching tube 1052. The second charge switching tube 1051 and the second discharge switching tube 1052 are sequentially connected between the second cell module 1053 and the second end of the DC/DC converter circuit 1032, for controlling the charge and discharge of the second cell module 1053. The controller 1033 in the energy storage device 107 is configured to implement any of the power supply control methods described above in the embodiments.

In other embodiments, the energy storage device 107 may include a plurality of battery modules.

Referring to fig. 8, fig. 8 is a block diagram illustrating a power conversion apparatus 103 according to an embodiment of the present application. As shown in fig. 8, the power conversion device 103 includes an AC/DC conversion circuit 1031, a DC/DC conversion circuit 1032, and a controller 1033. The AC/DC conversion circuit 1031 is connected to the DC/DC conversion circuit 1032 via a DC bus, and the AC/DC conversion circuit 1031 and the DC/DC conversion circuit 1032 are connected to the controller 1033, respectively. The power conversion device 103 may simultaneously control the AC/DC conversion circuit 1031 and the DC/DC conversion circuit 1032 through the controller 1033. The power conversion apparatus 103 may perform the steps in the embodiments of the respective power supply control methods described above through the controller 1033.

In some embodiments, the power conversion device 103 may also implement control of the AC/DC conversion circuit 1031 and the DC/DC conversion circuit 1032 by multiple controllers. Referring to fig. 9, fig. 9 is a block diagram illustrating a power conversion apparatus 103 according to another embodiment of the present application. As shown in fig. 9, the power conversion device 103 includes an AC/DC conversion circuit 1031, a DC/DC conversion circuit 1032, and a controller 1033, and the controller 1033 includes a first controller 1034 and a second controller 1035. The power conversion device 103 may control the AC/DC conversion circuit 1031 through the first controller 1034 and the DC/DC conversion circuit 1032 through the second controller 1035. The power conversion apparatus 103 may perform the steps in the embodiments of the respective power supply control methods described above through the first controller 1034 and the second controller 1035.

Referring to fig. 10, fig. 10 is a block diagram illustrating a structure of an energy storage device 107 according to another embodiment of the present application. As shown in fig. 10, the energy storage device 107 includes at least one battery module 1004 (only one battery module is shown in fig. 10), the power conversion apparatus 103, at least one processor 1001 (only one processor is shown in fig. 10), a memory 1002, and a computer program 1003, such as a charge control program, stored in the memory 1002 and executable on the at least one processor 1001. The processor 1001, when executing the computer program 1003, implements the steps in the embodiments of the respective power supply control methods described above.

The energy storage device 107 may include, but is not limited to, a processor 1001, a memory 1002, a battery module 1004, and a power conversion apparatus 103. It will be appreciated by those skilled in the art that fig. 10 is merely an example of the energy storage device 107 and is not limiting of the energy storage device 107 and may include more or fewer components than shown, or certain components may be combined, or different components.

The processor 1001 may be a central processing unit (Central Processing Unit, CPU), but may also be other general purpose processors, digital signal processors (Digital Signal Processor, DSP), application specific integrated circuits (Application Specific Integrated Circuit, ASIC), off-the-shelf programmable gate arrays (Field-Programmable Gate Array, FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, or the like. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like.

The memory 1002 may be an internal storage unit of the energy storage device 107, such as a hard disk or a memory of the energy storage device 107. The memory 1002 may also be an external storage device of the energy storage device 107, such as a plug-in hard disk, a Smart Media Card (SMC), a Secure Digital (SD) Card, a Flash memory Card (Flash Card) or the like, which are provided on the energy storage device 107. Alternatively, the memory 1002 may also include both internal and external storage units of the energy storage device 107. The memory 1002 is used to store computer programs and other programs and data needed by the energy storage device 107. The memory 1002 may also be used to temporarily store data that has been output or is to be output.

In addition, each functional unit in each embodiment of the present application may be integrated in one processing unit, or each unit may exist alone physically, or two or more units may be integrated in one unit. The integrated units may be implemented in hardware or in software functional units.

The integrated modules, if implemented in the form of software functional units and sold or used as a stand-alone product, may be stored in a computer readable storage medium. Based on such understanding, the present application implements all or part of the flow of the method of the above embodiments, and a computer program that may be implemented by a computer program to instruct related hardware may be stored in a computer readable storage medium, where the computer program when executed by a processor may implement the steps of each of the method embodiments described above. Wherein the computer program comprises computer program code, which may be in the form of source code, object code, executable files or in some intermediate form, etc. The computer readable medium may include: any entity or device capable of carrying computer program code, a recording medium, a U disk, a removable hard disk, a magnetic disk, an optical disk, a computer Memory, a Read-Only Memory (ROM), a random access Memory (RAM, random Access Memory), an electrical carrier signal, a telecommunications signal, a software distribution medium, and so forth. It should be noted that the content of the computer readable medium can be appropriately increased or decreased according to the requirements of the jurisdiction's jurisdiction and the patent practice, for example, in some jurisdictions, the computer readable medium does not include electrical carrier signals and telecommunication signals according to the jurisdiction and the patent practice.

In the foregoing embodiments, the descriptions of the embodiments are emphasized, and in part, not described or illustrated in any particular embodiment, reference is made to the related descriptions of other embodiments.

The above embodiments are only for illustrating the technical solution of the present application, and are not limiting thereof; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit and scope of the technical solutions of the embodiments of the present application, and are intended to be included in the scope of the present application.

Claims

1. A power supply control method, characterized by being applied to a power conversion device; the power conversion device comprises an AC/DC conversion circuit and a DC/DC conversion circuit; the first end of the AC/DC conversion circuit is used for being connected with a power supply, and the second end of the AC/DC conversion circuit is connected with the first end of the DC/DC conversion circuit through a direct current bus; the direct current bus is also used for being connected with a direct current load; the second end of the DC/DC conversion circuit is used for being connected with at least one battery module; the method comprises the following steps:

obtaining a second target current of the AC/DC conversion circuit according to a first target current currently output to the DC bus by the AC/DC conversion circuit, a required current of the battery module to be started and a required current of the battery module to be shut down;

and when the actual output current output by the AC/DC conversion circuit to the direct current bus is matched with the second target current, controlling the battery module to be closed and controlling the battery module to be opened.

2. The power supply control method according to claim 1, wherein the determining the battery module to be turned on and the battery module to be turned off according to the activation state of each connected battery module and the battery voltage of each battery module includes:

Determining a parallel voltage electric pressure range according to the battery voltage of the started battery module in each battery module;

if the battery voltage of the non-activated battery module is lower than a preset voltage threshold and the battery voltage is not in the parallel voltage range, determining the non-activated battery module as the battery module to be started, and determining all the started battery modules as the battery module to be closed;

and if the battery voltage of the non-activated battery module is within the parallel voltage range, determining the non-activated battery module as the battery module to be started.

3. The power supply control method according to claim 1, wherein when detecting that the dc load and the power supply are externally connected, determining the battery module to be turned on and the battery module to be turned off according to the activation state of each connected battery module and the battery voltage of each battery module, further comprises:

outputting a disable signal to the DC/DC conversion circuit to control the DC/DC conversion circuit to stop working;

and outputting an enabling signal to the DC/DC conversion circuit after the battery module to be started is started, so that the DC/DC conversion circuit works.

4. The power supply control method according to claim 1, wherein the obtaining the second target current of the AC/DC conversion circuit according to the first target current currently output to the DC bus by the AC/DC conversion circuit, the required current of the battery module to be turned on, and the required current of the battery module to be turned off includes:

Adding a first target current currently output to the direct current bus by the AC/DC conversion circuit to the required current of the battery module to be started to obtain a current sum;

and subtracting the required current of the battery module to be closed from the current sum to obtain the second target current.

5. The power supply control method according to claim 1, wherein the controlling the battery module to be turned off and the controlling the battery module to be turned on includes:

controlling the battery module to be closed;

and after the battery module to be closed is confirmed to be closed, controlling the battery module to be opened.

6. The power supply control method according to claim 5, wherein each battery module includes a cell module, a charge switching tube, and a discharge switching tube; the charging switch tube and the discharging switch tube are used for controlling the charging and discharging states of the battery cell module; the controlling the battery module to be closed and the controlling the battery module to be opened includes:

closing a charging switch tube and a discharging switch tube of the battery module to be closed;

and after the fact that the charging switch tube and the discharging switch tube of the battery module to be closed are both closed is confirmed, the charging switch tube and the discharging switch tube of the battery module to be opened are turned on.

7. The power supply control method according to any one of claims 1 to 6, characterized in that the method further comprises:

and if the deviation between the second target current and the actual output current is larger than a preset current threshold value within the preset waiting time for outputting the first driving signal, generating fault alarm information.

8. A power conversion device is characterized by comprising a controller, an AC/DC conversion circuit and a DC/DC conversion circuit; the first end of the AC/DC conversion circuit is used for being connected with a power supply, and the second end of the AC/DC conversion circuit is connected with the first end of the DC/DC conversion circuit through a direct current bus; the direct current bus is also used for being connected with a direct current load; the second end of the DC/DC conversion circuit is used for being connected with at least one battery module; the controller is configured to execute the power supply control method according to any one of claims 1 to 7.

9. An energy storage device comprising a battery module, a power conversion means, a memory, a processor and a computer program stored in the memory and executable on the processor, characterized in that the processor implements the power supply control method according to any one of claims 1-7 when executing the computer program.

10. A computer-readable storage medium storing a computer program, wherein the computer program, when executed by a processor, implements the power supply control method according to any one of claims 1 to 7.