Energy storage battery low power consumption control method and energy storage power supply system

Abstract

The present invention discloses a low-power consumption control method for an energy storage battery and an energy storage power supply system. The method is applied to an energy storage power supply system, wherein the energy storage power supply system comprises an energy storage battery, a DC / DC module, a power supply module and a battery management system, wherein the energy storage battery is connected to a load through the DC / DC module and a DC bus in sequence, and the power supply module is connected to the energy storage battery, the DC / DC module and the battery management system respectively, and is characterized in that the power supply module is also connected to the DC bus, and the energy storage power supply system further comprises a current detection module, and the method comprises: after the DC / DC module outputs electric energy to the DC bus, obtaining the DC bus current value of the energy storage power supply system; and switching the energy storage battery or the DC bus to supply power to the power supply module according to the DC bus current value. Through the present invention, it is possible to avoid unnecessary consumption of electric energy of the energy storage battery and improve the utilization rate of the energy storage battery.

Description

Technical Field

[0001] The present invention relates to the field of electronic power technology, and in particular to a low power consumption control method for an energy storage battery and an energy storage power supply system. Background Art

[0002] Under the current overall requirements of carbon neutrality and carbon peak, the proportion of clean energy applications will become increasingly larger. Photovoltaics, as a clean energy, will provide important guarantees for carbon neutrality, and energy storage batteries, as energy storage units for photovoltaic power generation, play an important role in clean energy systems. As energy storage units, energy storage batteries have the problem that the energy charging and discharging utilization rate cannot reach 100%. For example, the energy storage battery is charged with 10kWh, and the final discharge is only 8kWh. One reason is that the energy storage battery has low power protection and cannot be fully discharged. Another reason is that the control components of the energy storage power supply system have operating power consumption, which leads to internal power consumption in the entire energy storage power supply system, thereby reducing the power utilization rate of the energy storage battery.

[0003] With regard to the problem that the control components of the energy storage power supply system in the prior art have operating power consumption, resulting in low power utilization of the energy storage battery, no effective solution has been proposed so far. Summary of the invention

[0004] The embodiments of the present invention provide a low power consumption control method for an energy storage battery and an energy storage power supply system to solve the problem in the prior art that the control components of the energy storage power supply system have operating power consumption, resulting in low power utilization of the energy storage battery.

[0005] In order to solve the above technical problems, the present invention provides a low-power consumption control method for an energy storage battery, which is applied to an energy storage power supply system. The energy storage power supply system includes an energy storage battery, a DC / DC module, a power module and a battery management system. The energy storage battery is connected to a load through the DC / DC module and a DC bus in sequence. The power module is connected to the energy storage battery, the DC / DC module and the battery management system respectively. It is characterized in that the power module is also connected to the DC bus. The energy storage power supply system also includes a current detection module. The method includes:

[0006] After the DC / DC module outputs electric energy to the DC bus, obtaining a DC bus current value of the energy storage power supply system;

[0007] The energy storage battery or the DC bus is switched according to the DC bus current value to supply power to the power module.

[0008] Further, switching the energy storage battery or the DC bus to supply power to the power module according to the DC bus current value includes:

[0009] Determining whether the DC bus current value meets a first preset condition;

[0010] If yes, controlling the DC bus to supply power to the power module;

[0011] If not, the energy storage battery is controlled to supply power to the power module.

[0012] Furthermore, the first preset condition is:

[0013] The DC bus current value is less than a preset current value; wherein the preset current value is determined according to the first DC bus current value and the second DC bus current value;

[0014] Among them, the first DC bus current value is the DC bus current value when the DC bus supplies power to the power module and the output power of the DC / DC module is zero; the second DC bus current value is the DC bus current value when the energy storage battery supplies power to the power module and the output power of the DC / DC module is zero.

[0015] Furthermore, the preset current value is determined according to the first DC bus current value and the second DC bus current value, including:

[0016] The preset current value is equal to the difference between the second DC bus current value and the first DC bus current value.

[0017] Further, after controlling the DC bus to supply power to the power module, the method further includes:

[0018] Determining whether the power level of the energy storage battery is less than or equal to a preset threshold;

[0019] If yes, the DC bus is controlled to start charging the energy storage battery.

[0020] Further, after controlling the energy storage battery to supply power to the power module, the method further includes:

[0021] Determining whether the power level of the energy storage battery is less than or equal to a preset threshold;

[0022] If yes, the DC bus is controlled to start charging the energy storage battery.

[0023] The present invention also provides an energy storage power supply system, comprising an energy storage battery, a DC / DC module, a power module and a battery management system, wherein the energy storage battery is connected to a load via the DC / DC module and a DC bus in sequence, the power module is respectively connected to the energy storage battery, the DC / DC module and the battery management system, the power module is also connected to the DC bus, the energy storage power supply system further comprises a current detection module for obtaining a DC bus current value of the energy storage power supply system; the battery management system is also used to switch the energy storage battery or the DC bus to supply power to the power module according to the DC bus current value.

[0024] Furthermore, the energy storage power supply system also includes:

[0025] The first switch is arranged between the energy storage battery and the power module, and is used to control the connection between the energy storage battery and the power module.

[0026] Furthermore, the energy storage power supply system also includes:

[0027] A manual switch is arranged in parallel with the first switch, and is used for manually controlling the energy storage battery to supply power to the power module.

[0028] Furthermore, the energy storage power supply system also includes:

[0029] The second switch is arranged between the DC bus and the power module, and is used to control the connection and disconnection between the DC bus and the power module.

[0030] Furthermore, the energy storage power supply system also includes:

[0031] The third switch is arranged between the energy storage battery and the DC / DC module, and is used to control the on-off between the energy storage battery and the DC / DC module.

[0032] Furthermore, the energy storage power supply system also includes:

[0033] A charging circuit, comprising a fourth switch and a first resistor arranged in series, wherein the charging circuit is arranged between the energy storage battery and the DC / DC module, and is used to control whether the energy storage battery charges the DC / DC module.

[0034] The present invention also provides a computer-readable storage medium on which a computer program is stored, and when the program is executed by a processor, the above-mentioned energy storage battery low power consumption control method is implemented.

[0035] By applying the technical solution of the present invention, by obtaining the DC bus current value of the energy storage power supply system, the energy storage battery or the DC bus is switched to power the power module according to the DC bus current value. When the load is low, the DC bus can be switched to power the power module, which can avoid unnecessary consumption of the energy storage battery and improve the utilization rate of the energy storage battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 According to the structural diagram of the existing energy storage power supply system;

[0037] Figure 2 A structural diagram of an energy storage power supply system according to an embodiment of the present invention;

[0038] Figure 3 is a flow chart of a method for controlling low power consumption of an energy storage battery according to an embodiment of the present invention;

[0039] Figure 4 4 is a structural diagram of an energy storage power supply system according to another embodiment of the present invention. DETAILED DESCRIPTION

[0040] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0041] The terms used in the embodiments of the present invention are only for the purpose of describing specific embodiments, and are not intended to limit the present invention. The singular forms "a", "said" and "the" used in the embodiments of the present invention and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings, and "multiple" generally includes at least two.

[0042] It should be understood that the term "and / or" used in this article is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0043] It should be understood that although the terms first, second, third, etc. may be used to describe switches in the embodiments of the present invention, the switches should not be limited to these terms. These terms are only used to distinguish switches arranged at different positions. For example, without departing from the scope of the embodiments of the present invention, the first switch may also be referred to as the second switch, and similarly, the second switch may also be referred to as the first switch.

[0044] As used herein, the words "if" and "if" may be interpreted as "at the time of" or "when" or "in response to determining" or "in response to detecting", depending on the context. Similarly, the phrases "if it is determined" or "if (stated condition or event) is detected" may be interpreted as "when it is determined" or "in response to determining" or "when detecting (stated condition or event)" or "in response to detecting (stated condition or event)", depending on the context.

[0045] It should also be noted that the term "includes", "comprising" or any other variation thereof is intended to cover non-exclusive inclusion, so that a commodity or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such commodity or device. In the absence of more restrictions, the elements defined by the sentence "comprising a ..." do not exclude the existence of other identical elements in the commodity or device including the elements.

[0046] The optional embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0047] Example 1

[0048] This embodiment provides a low power consumption control method for an energy storage battery 1, which is applied to an energy storage power supply system. Figure 1 According to the structure diagram of the existing energy storage power supply system, Figure 1 As shown, the existing energy storage power supply system includes an energy storage battery 1, a DC / DC module 2, a power module 3 and a battery management system 4. The energy storage battery 1 is connected to the load 5 through the DC / DC module 2 and the DC bus in sequence. The power module 3 is connected to the energy storage battery 1, the DC / DC module 2 and the battery management system 4 respectively. The above energy storage power supply system also includes a power grid. The power grid is connected to the DC / DC module 2 through an AC / DC module, which is used to output electric energy to the DC bus to realize power supply for the load 5. In the above energy storage power supply system, the battery management system 4 needs to control the charging and discharging of the energy storage battery 1 through a control component, and the energy storage battery 1 is connected to the power module 3. The above operations all need to consume a part of electric energy, which is the internal power consumption of the energy storage power supply system. In the above energy storage system, the internal power consumption is provided by the energy storage battery 1, so the internal power consumption will reduce the power utilization rate of the energy storage battery 1. When the load 5 is low, the power of the DC bus is sufficient. Therefore, it can be considered to power the power module 3 through the DC bus to reduce the power consumption of the energy storage battery 1 and improve the utilization rate of the energy storage battery 1. Based on the above concept, an energy storage power supply system is provided. Figure 2 is a structural diagram of an energy storage power supply system according to an embodiment of the present invention, such as Figure 2As shown, based on the existing energy storage power supply system, the power supply module 3 is also connected to the DC bus, and the energy storage power supply system also includes a current detection module 6.

[0049] This embodiment also provides a method for controlling low power consumption of an energy storage battery. Figure 3 Flow chart of a method for controlling low power consumption of an energy storage battery according to an embodiment of the present invention. Figure 3 As shown, the above energy storage battery low power consumption control method includes:

[0050] S101, after the DC / DC module outputs electric energy to the DC bus, a DC bus current value of the energy storage power supply system is obtained.

[0051] S102, switching the energy storage battery or the DC bus to supply power to the power module according to the DC bus current value.

[0052] The energy storage battery low power consumption control method of this embodiment obtains the DC bus current value of the energy storage power supply system, and switches the energy storage battery or the DC bus to power the power module according to the DC bus current value. When the load is low, the DC bus can be switched to power the power module, which can avoid unnecessary consumption of the energy storage battery and improve the utilization rate of the energy storage battery.

[0053] Example 2

[0054] This embodiment provides another energy storage battery low power consumption control method, the DC bus current can reflect that in order to switch the power supply of the power module according to the load, the energy storage battery or the DC bus is switched to power the power module according to the DC bus current value, including: judging whether the DC bus current value meets the first preset condition; if yes, it indicates that the load is very low, and the DC bus is controlled to power the power module to reduce the power consumption of the energy storage battery; if not, it indicates that the load is high, and the energy storage battery is controlled to power the power module. Among them, the above-mentioned first preset condition is: the DC bus current value is less than the preset current value; wherein the preset current value is determined according to the first DC bus current value I1 and the second DC bus current value I2. The first DC bus current value I1 is the DC bus current value when the DC bus supplies power to the power module and the output power of the DC / DC module is zero; the second DC bus current value I2 is the DC bus current value when the energy storage battery supplies power to the power module and the output power of the DC / DC module is zero. The preset current value is equal to the difference between the second DC bus current value I2 and the first DC bus current value I1. In specific implementation, after the energy storage system is powered on, the energy storage battery is controlled to be connected to the DCDC module and the power module, while the DC / DC module does not output current to the outside, and the current current value of the bus is detected and marked as the first DC bus current I1; the energy storage battery is controlled to be disconnected from the DCDC module, the energy storage battery is disconnected from the power module, and the DC bus is connected to the power module, and the current value of the bus current is detected and marked as the second DC bus current value I2, and the preset current value Ik=I2-I1 is calculated.

[0055] When the power of the energy storage battery is lower than a certain value, the energy storage battery needs to be charged. Therefore, after controlling the DC bus to supply power to the power module, the above method further includes: judging whether the power of the energy storage battery is less than or equal to a preset threshold; if so, it indicates that the power of the energy storage battery is insufficient, and the DC bus is controlled to start charging the energy storage battery; if not, it indicates that the power of the energy storage battery is normal, and the DC bus continues to be controlled to supply power to the power module.

[0056] Similarly, after controlling the energy storage battery to supply power to the power module, the method further includes: determining whether the power level of the energy storage battery is less than or equal to a preset threshold; if so, it indicates that the power level of the energy storage battery is insufficient, and the DC bus is controlled to start charging the energy storage battery; if not, it indicates that the power level of the energy storage battery is normal, and the energy storage battery continues to be controlled to supply power to the power module.

[0057] Example 3

[0058] This embodiment provides an energy storage power supply system, as mentioned above Figure 1As shown in, the energy storage power supply system includes an energy storage battery 1, a DC / DC module 2, a power module 3 and a battery management system 4. The energy storage battery 1 is connected to a load 5 through the DC / DC module 2 and a DC bus in sequence. The power module 3 is respectively connected to the energy storage battery 1, the DC / DC module 2 and the battery management system 4. The power module 3 is also connected to the DC bus. The energy storage power supply system also includes a current detection module 6 for obtaining a DC bus current value of the energy storage power supply system; the battery management system 4 is also used to switch the energy storage battery 1 or the DC bus to supply power to the power module 3 according to the DC bus current value.

[0059] The energy storage power supply system of this embodiment obtains the DC bus current value of the energy storage power supply system, and switches the energy storage battery 1 or the DC bus to supply power to the power module 3 according to the DC bus current value. When the load 5 is low, the DC bus can be switched to supply power to the power module 3, thereby avoiding unnecessary consumption of electric energy of the energy storage battery 1 and improving the utilization rate of the energy storage battery 1.

[0060] Example 4

[0061] This embodiment provides another energy storage power supply system. Figure 4 is a structural diagram of an energy storage power supply system according to another embodiment of the present invention, in order to switch the power supply of the power module 3, such as Figure 4 As shown, the energy storage power supply system further includes: a first switch K1, which is arranged between the energy storage battery 1 and the power module 3, and is used to control the on-off between the energy storage battery 1 and the power module 3. A manual switch S is arranged in parallel with the first switch K1, and is used to manually control the energy storage battery 1 to supply power to the power module 3. In a specific implementation, the energy storage battery 1 can supply power to the power module 3 by manually pressing the manual switch S. A second switch K2 is arranged between the DC bus and the power module 3, and is used to control the on-off between the DC bus and the power module 3.

[0062] When the power level of the energy storage battery 1 is lower than a certain value, the energy storage battery 1 needs to be charged. At this time, the energy storage battery 1 and the DC / DC module 2 need to be connected. When the energy storage battery 1 supplies power to the DC bus, the energy storage battery 1 and the DC / DC module 2 also need to be connected. Therefore, the energy storage power supply system further includes: a third switch K3, which is arranged between the energy storage battery 1 and the DC / DC module 2, and is used to control the on-off between the DC / DC module 2 and the charging of the energy storage battery 1.

[0063] Since there is a bus capacitor (not shown in the figure) in the DC / DC module 2, the bus capacitor needs to be charged before supplying power to the load 5. Therefore, the energy storage power supply system also includes: a charging circuit 7, which includes a fourth switch K4 and a first resistor R1 arranged in series. The charging circuit 7 is arranged between the energy storage battery 1 and the DC / DC module 2, and is used to control whether the energy storage battery 1 charges the DC / DC module 2.

[0064] In order to achieve unidirectional current conduction, a diode D is further provided between the DC bus and the power module 3 to control the current to flow only from the DC bus to the power module 3 .

[0065] In order to realize overload, short circuit and undervoltage protection functions, such as Figure 4 As shown, a first circuit breaker QF1 is provided between the energy storage battery 1 and the power module 3 , and a second circuit breaker QF2 is also provided between the DC bus and the power module 3 .

[0066] In order to achieve unidirectional current conduction, a diode is also arranged between the DC bus and the power module to control the current to flow only from the DC bus to the power module.

[0067] The control process of the energy storage power supply system in this embodiment is as follows:

[0068] S1, the energy storage battery is powered on, the battery management system controls the third switch K3 and the first switch K1 to close, and at the same time controls the DC / DC module not to output electric energy to the outside, and the current detection module obtains the current DC bus current value, which is marked as the first DC bus current value I1.

[0069] S2, the power management system controls the second switch K2 to close and the first switch K1 to open, the current detection module obtains the current DC bus current, marked as the second DC bus current value I2, and after detecting the current value, controls the first switch K1 to close and the second switch K2 to open. The current detection module transmits the current values ​​I1 and I2 to the battery management system through CAN communication, and the battery management system calculates the preset current value Ik=I2-I1.

[0070] S3, the DC / DC module opens the output power, outputs the current to the DC bus, detects the bus current value I in real time, and transmits the DC bus current value to the battery management system through the CAN bus;

[0071] S4, the battery management system performs low power consumption control according to the DC bus current value and the battery power.

[0072] State 1: When I≤Ik, and the battery power is greater than 10%, the energy storage battery does not need to output current to the DC bus. The battery management system controls the second switch K2 to close, and controls the first switch K1 and the third switch K3 to open, so that the energy storage battery does not discharge externally;

[0073] State 2: When I≤Ik, and the battery power is less than or equal to 10%, the energy storage system needs to be charged. The battery management system controls the third switch K3 to remain closed, controls the second switch K2 to close, and disconnects the first switch K1. The DC / DC module starts to charge the energy storage battery.

[0074] State 3: When I>Ik, and the battery power is greater than 10%, the energy storage battery needs to output current to the DC bus, and the battery management system controls the third switch K3 and the first switch K1 to close, and controls the second switch K2 to open;

[0075] State 4: When I>Ik, and the battery power is less than or equal to 10%, the energy storage battery needs to be charged. The battery management system controls the third switch K3 to close, controls the second switch K2 to close, and disconnects the first switch K1. The DC / DC module starts to charge the energy storage battery.

[0076] In this embodiment, the battery management system communicates with the DC / DC module via the CAN bus. The battery management system obtains the DC bus current value through communication, and controls the energy storage battery to close or disconnect according to the DC bus current value, so that the energy storage battery can be connected to the grid and the load has no power demand. When the power consumption of the energy storage battery is minimized.

[0077] The system embodiment described above is merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0078] Through the description of the above implementation methods, those skilled in the art can clearly understand that each implementation method can be implemented by means of software plus a necessary general hardware platform, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solution is essentially or the part that contributes to the prior art can be embodied in the form of a software product, and the computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a disk, an optical disk, etc., including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0079] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A low power consumption control method for an energy storage battery, applied to an energy storage power supply system, wherein the energy storage power supply system comprises an energy storage battery, a DC / DC module, a power module and a battery management system, wherein the energy storage battery is connected to a load through the DC / DC module and a DC bus in sequence, and the power module is connected to the energy storage battery, the DC / DC module and the battery management system respectively, characterized in that: The power supply module is also connected to the DC bus, the energy storage power supply system also includes a current detection module, and the method includes: After the DC / DC module outputs electric energy to the DC bus, obtaining a DC bus current value of the energy storage power supply system; Switching the energy storage battery or the DC bus to supply power to the power module according to the DC bus current value; including: judging whether the DC bus current value meets a first preset condition; if yes, controlling the DC bus to supply power to the power module; if not, controlling the energy storage battery to supply power to the power module; the first preset condition is: the DC bus current value is less than a preset current value; wherein the preset current value is equal to the difference between the second DC bus current value and the first DC bus current value; wherein the first DC bus current value is the DC bus current value when the DC bus supplies power to the power module and the output power of the DC / DC module is zero; the second DC bus current value is the DC bus current value when the energy storage battery supplies power to the power module and the output power of the DC / DC module is zero.

2. The method according to claim 1, characterized in that After controlling the DC bus to supply power to the power module, the method further includes: Determining whether the power level of the energy storage battery is less than or equal to a preset threshold; If yes, the DC bus is controlled to start charging the energy storage battery.

3. The method according to claim 1, characterized in that After controlling the energy storage battery to supply power to the power module, the method further includes: Determining whether the power level of the energy storage battery is less than or equal to a preset threshold; If yes, the DC bus is controlled to start charging the energy storage battery.

4. An energy storage power supply system, comprising an energy storage battery, a DC / DC module, a power module and a battery management system, wherein the energy storage battery is connected to a load through the DC / DC module and a DC bus in sequence, and the power module is connected to the energy storage battery, the DC / DC module and the battery management system respectively, characterized in that: The power supply module is also connected to the DC bus, and the energy storage power supply system also includes a current detection module for obtaining the DC bus current value of the energy storage power supply system; the battery management system is also used to switch the energy storage battery or the DC bus to power the power supply module according to the DC bus current value; The method includes: determining whether the DC bus current value satisfies a first preset condition; if yes, controlling the DC bus to supply power to the power module; if not, controlling the energy storage battery to supply power to the power module; the first preset condition is: the DC bus current value is less than a preset current value; wherein the preset current value is equal to the difference between the second DC bus current value and the first DC bus current value; wherein the first DC bus current value is the DC bus current value when the DC bus supplies power to the power module and the output power of the DC / DC module is zero; and the second DC bus current value is the DC bus current value when the energy storage battery supplies power to the power module and the output power of the DC / DC module is zero.

5. The energy storage power supply system according to claim 4, characterized in that: The energy storage power supply system also includes: The first switch is arranged between the energy storage battery and the power module, and is used to control the connection between the energy storage battery and the power module.

6. The energy storage power supply system according to claim 5, characterized in that: The energy storage power supply system also includes: A manual switch is arranged in parallel with the first switch, and is used for manually controlling the energy storage battery to supply power to the power module.

7. The energy storage power supply system according to claim 4, characterized in that: The energy storage power supply system also includes: The second switch is arranged between the DC bus and the power module, and is used to control the connection and disconnection between the DC bus and the power module.

8. The energy storage power supply system according to claim 4, characterized in that: The energy storage power supply system also includes: The third switch is arranged between the energy storage battery and the DC / DC module, and is used to control the on-off between the energy storage battery and the DC / DC module.

9. The energy storage power supply system according to claim 4, characterized in that: The energy storage power supply system also includes: A charging circuit, comprising a fourth switch and a first resistor arranged in series, wherein the charging circuit is arranged between the energy storage battery and the DC / DC module, and is used to control whether the energy storage battery charges the DC / DC module.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the method according to any one of claims 1 to 3 is implemented.

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