阅读说明：本技术 一种混合储能系统的控制方法、装置、设备及介质 (Control method, device, equipment and medium of hybrid energy storage system ) 是由 闵歆 李杨 陈圣金 吴星亮 于 2021-08-31 设计创作，主要内容包括：本申请公开了一种混合储能系统的控制方法,包括：获取混合储能系统中储能电池的无功补偿功率；将无功补偿功率反馈至混合储能系统的超级电容器,以对混合储能系统进行控制。相较于现有技术而言,由于该控制方法增加了将储能电池的无功补偿功率反馈至混合储能系统中超级电容器的步骤,这样就可以相对降低混合储能系统中的电流跟踪误差,并能快速恢复混合储能系统中的直流链路电压。相应的,本申请所提供的一种混合储能系统的控制装置、设备及介质,同样具有上述有益效果。(The application discloses a control method of a hybrid energy storage system, comprising the following steps: acquiring reactive compensation power of an energy storage battery in the hybrid energy storage system; and feeding back the reactive compensation power to a super capacitor of the hybrid energy storage system so as to control the hybrid energy storage system. Compared with the prior art, the control method adds the step of feeding back the reactive compensation power of the energy storage battery to the super capacitor in the hybrid energy storage system, so that the current tracking error in the hybrid energy storage system can be relatively reduced, and the direct current link voltage in the hybrid energy storage system can be quickly recovered. Correspondingly, the control device, the equipment and the medium of the hybrid energy storage system have the beneficial effects.)

1. A method of controlling a hybrid energy storage system, comprising:

acquiring reactive compensation power of an energy storage battery in the hybrid energy storage system;

and feeding back the reactive compensation power to a super capacitor of the hybrid energy storage system so as to control the hybrid energy storage system.

2. The control method according to claim 1, wherein the process of obtaining the reactive compensation power of the energy storage battery in the hybrid energy storage system comprises:

acquiring the total current of the hybrid energy storage system, and acquiring the reference current of the energy storage battery according to the total current of the hybrid energy storage system;

and determining the reactive compensation power according to the reference current of the energy storage battery.

3. The control method according to claim 2, wherein the process of obtaining the total current of the hybrid energy storage system includes:

acquiring the total current of the hybrid energy storage system according to a current mathematical model;

wherein, the expression of the mathematical current model is as follows:

i_tot(t)＝K_{p_vdc}v_er+K_{i_vdc}∫v_erdt；

in the formula i_totIs the total current of the hybrid energy storage system, K_{p_vdc}And K_{i_vdc}Respectively a proportional constant and an integral constant, v, of a voltage control loop in the hybrid energy storage system_erTo the fault voltage, t is time.

4. The control method according to claim 3, wherein the process of obtaining the reference current of the energy storage battery according to the total current of the hybrid energy storage system comprises:

acquiring a reference current of the energy storage battery according to the total current of the hybrid energy storage system based on a target mathematical model;

wherein the expression of the target mathematical model is:

in the formula i_brefIs a reference current, ω, of the energy storage cell_cIs the cut-off frequency of the low-pass filter in the hybrid energy storage system, s is a Laplace transform factor, i_totIs the total current of the hybrid energy storage system.

5. The control method according to claim 4, wherein the determining the reactive compensation power according to the reference current of the energy storage battery comprises:

determining the reactive compensation power according to the reference current of the energy storage battery based on a power compensation model;

wherein the expression of the power compensation model is as follows:

P_{b_uncomp}(s)＝(i_bref(s)-i_b(s))v_b(s)

in the formula, P_{b_uncomp}For the reactive compensation power i_brefIs a reference current of the energy storage cell, i_bIs the actual current of the energy storage cell, v_bAnd s is the voltage of the energy storage battery and is a Laplace transform factor.

6. The control method according to claim 1, wherein the process of feeding back the reactive compensation power to the super capacitor of the hybrid energy storage system to control the hybrid energy storage system comprises:

obtaining reactive compensation current of the energy storage battery by using the reactive compensation power, and obtaining instantaneous effective current of the energy storage battery;

and jointly acting the reactive compensation current of the energy storage battery, the instantaneous effective current of the energy storage battery and the actual current of the super capacitor on the super capacitor so as to control the hybrid energy storage system.

7. A control apparatus of a hybrid energy storage system, comprising:

the power acquisition module is used for acquiring reactive compensation power of an energy storage battery in the hybrid energy storage system;

and the system control module is used for feeding the reactive compensation power back to the super capacitor of the hybrid energy storage system so as to control the hybrid energy storage system.

8. A control apparatus of a hybrid energy storage system, characterized by comprising:

a memory for storing a computer program;

a processor for implementing the steps of a method of controlling a hybrid energy storage system according to any one of claims 1 to 6 when executing the computer program.

9. A computer-readable storage medium, characterized in that a computer program is stored thereon, which computer program, when being executed by a processor, carries out the steps of a method of controlling a hybrid energy storage system according to any one of claims 1 to 6.

Technical Field

The invention relates to the technical field of hybrid energy storage, in particular to a control method, a control device, control equipment and a control medium of a hybrid energy storage system.

Background

The hybrid energy storage system can adopt different storage technologies to improve the performance of the whole energy storage system, so that the hybrid energy storage system is widely applied in actual life. Because the combination mode of the energy storage battery and the super capacitor can effectively solve the power fluctuation of different changes in the hybrid energy storage system and reduce the pressure of the battery energy storage system, the combination mode of the energy storage battery and the super capacitor is one of the most common configurations of the current hybrid energy storage system.

In the prior art, the total current in the hybrid energy storage system is divided into an average current and an instantaneous current by a low-pass filter, wherein the average current generated by the low-pass filter is used as a reference current of the energy storage battery in the hybrid energy storage system, and the instantaneous current generated by the low-pass filter is used as a reference current of the super capacitor in the hybrid energy storage system. Because the dynamic changes of the energy storage battery, the battery controller and the bidirectional DC-DC Converter (Direct Current Converter) in the hybrid energy storage system are relatively slow, a large Current tracking error exists in the hybrid energy storage system, and the voltage of the internal Direct Current link cannot be quickly recovered. At present, no effective solution exists for the technical problem.

Disclosure of Invention

In view of the above, an object of the present invention is to provide a method, an apparatus, a device and a medium for controlling a hybrid energy storage system, so as to reduce a current tracking error in the hybrid energy storage system and quickly recover a dc link voltage in the hybrid energy storage system. The specific scheme is as follows:

a method of controlling a hybrid energy storage system, comprising:

acquiring reactive compensation power of an energy storage battery in the hybrid energy storage system;

and feeding back the reactive compensation power to a super capacitor of the hybrid energy storage system so as to control the hybrid energy storage system.

Preferably, the process of obtaining the reactive compensation power of the energy storage battery in the hybrid energy storage system includes:

acquiring the total current of the hybrid energy storage system, and acquiring the reference current of the energy storage battery according to the total current of the hybrid energy storage system;

and determining the reactive compensation power according to the reference current of the energy storage battery.

Preferably, the process of obtaining the total current of the hybrid energy storage system includes:

acquiring the total current of the hybrid energy storage system according to a current mathematical model;

wherein, the expression of the mathematical current model is as follows:

i_tot(t)＝K_{p_vdc}v_er+K_{i_vdc}∫v_erdt；

in the formula i_totIs the total current of the hybrid energy storage system, K_{p_vdc}And K_{i_vdc}Respectively a proportional constant and an integral constant, v, of a voltage control loop in the hybrid energy storage system_erTo the fault voltage, t is time.

Preferably, the process of obtaining the reference current of the energy storage battery according to the total current of the hybrid energy storage system includes:

acquiring a reference current of the energy storage battery according to the total current of the hybrid energy storage system based on a target mathematical model;

wherein the expression of the target mathematical model is:

in the formula i_brefIs a reference current, ω, of the energy storage cell_cIs the cut-off frequency of the low-pass filter in the hybrid energy storage system, s is a Laplace transform factor, i_totIs the total current of the hybrid energy storage system.

Preferably, the determining the reactive compensation power according to the reference current of the energy storage battery includes:

determining the reactive compensation power according to the reference current of the energy storage battery based on a power compensation model;

wherein the expression of the power compensation model is as follows:

P_{b_uncomp}(s)＝(i_bref(s)-i_b(s))v_b(s)

in the formula, P_{b_uncomp}For the reactive compensation power i_brefIs a reference current of the energy storage cell, i_bIs the actual current of the energy storage cell, v_bAnd s is the voltage of the energy storage battery and is a Laplace transform factor.

Preferably, the process of feeding back the reactive compensation power to a super capacitor of the hybrid energy storage system to control the hybrid energy storage system includes:

obtaining reactive compensation current of the energy storage battery by using the reactive compensation power, and obtaining instantaneous effective current of the energy storage battery;

and jointly acting the reactive compensation current of the energy storage battery, the instantaneous effective current of the energy storage battery and the actual current of the super capacitor on the super capacitor so as to control the hybrid energy storage system.

Correspondingly, the invention also discloses a control device of the hybrid energy storage system, which comprises:

the power acquisition module is used for acquiring reactive compensation power of an energy storage battery in the hybrid energy storage system;

and the system control module is used for feeding the reactive compensation power back to the super capacitor of the hybrid energy storage system so as to control the hybrid energy storage system.

Correspondingly, the invention also discloses a control device of the hybrid energy storage system, which comprises:

a memory for storing a computer program;

a processor for implementing the steps of a method of controlling a hybrid energy storage system as disclosed in the foregoing when executing said computer program.

Accordingly, the present invention also discloses a computer readable storage medium having a computer program stored thereon, which, when being executed by a processor, implements the steps of a method for controlling a hybrid energy storage system as disclosed in the foregoing.

Therefore, in the invention, firstly, the reactive compensation power of the energy storage battery in the hybrid energy storage system is obtained, and then, the reactive compensation power is fed back to the super capacitor in the hybrid energy storage system, so as to control the hybrid energy storage system. Compared with the prior art, the control method adds the step of feeding back the reactive compensation power of the energy storage battery to the super capacitor in the hybrid energy storage system, so that the current tracking error in the hybrid energy storage system can be relatively reduced, and the direct current link voltage in the hybrid energy storage system can be quickly recovered. Correspondingly, the control device, the equipment and the medium of the hybrid energy storage system have the beneficial effects.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the provided drawings without creative efforts.

Fig. 1 is a flowchart of a control method of a hybrid energy storage system according to an embodiment of the present invention;

fig. 2 is a schematic diagram illustrating a hybrid energy storage system controlled by reactive compensation power of an energy storage battery according to an embodiment of the present invention;

fig. 3 is a structural diagram of a control device of a hybrid energy storage system according to an embodiment of the present invention;

fig. 4 is a structural diagram of a control device of a hybrid energy storage system according to an embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Referring to fig. 1, fig. 1 is a flowchart of a control method of a hybrid energy storage system according to an embodiment of the present invention, where the control method includes:

step S11: acquiring reactive compensation power of an energy storage battery in the hybrid energy storage system;

step S12: and feeding back the reactive compensation power to a super capacitor of the hybrid energy storage system so as to control the hybrid energy storage system.

In this embodiment, a control method of a hybrid energy storage system is provided, where the control method is used to control the hybrid energy storage system, so that a current tracking error in the hybrid energy storage system can be reduced, and a dc link voltage in the hybrid energy storage system can be recovered quickly.

In the control method, firstly, the reactive compensation power of the energy storage battery in the hybrid energy storage system is obtained, and after the reactive compensation power of the energy storage battery in the hybrid energy storage system is obtained, the reactive compensation power of the energy storage battery is fed back to the super capacitor of the hybrid energy storage system, so that the hybrid energy storage system is controlled.

It can be understood that when the reactive compensation power of the energy storage battery is fed back to the super capacitor of the hybrid energy storage system, the reactive compensation power of the energy storage battery is equivalently introduced into the feedback control of the hybrid energy storage system, so that the current tracking error of the hybrid energy storage system can be relatively reduced. It is conceivable that, after the current tracking error in the hybrid energy storage system is reduced, the hybrid energy storage system can quickly recover the dc link voltage therein.

In addition, by the control mode, the pressure of a primary energy storage system in the hybrid energy storage system can be reduced in the load and power generation step change of the hybrid energy storage system, and the overshoot phenomenon of the direct-current link voltage in the hybrid energy storage system can be inhibited.

Therefore, in this embodiment, firstly, the reactive compensation power of the energy storage battery in the hybrid energy storage system is obtained, and then, the reactive compensation power is fed back to the super capacitor in the hybrid energy storage system, so as to control the hybrid energy storage system. Compared with the prior art, the control method adds the step of feeding back the reactive compensation power of the energy storage battery to the super capacitor in the hybrid energy storage system, so that the current tracking error in the hybrid energy storage system can be relatively reduced, and the direct current link voltage in the hybrid energy storage system can be quickly recovered.

Based on the above embodiments, this embodiment further describes and optimizes the technical solution, and as a preferred implementation, the above steps: the process of obtaining the reactive compensation power of the energy storage battery in the hybrid energy storage system comprises the following steps:

acquiring the total current of the hybrid energy storage system, and acquiring the reference current of the energy storage battery according to the total current of the hybrid energy storage system;

and determining reactive compensation power according to the reference current of the energy storage battery.

In this embodiment, a specific implementation method of reactive compensation power of an energy storage battery in a hybrid energy storage system is provided, in the process of obtaining the reactive compensation power of the energy storage battery, first obtaining a total current of the hybrid energy storage system, and obtaining a reference current of the energy storage battery according to the total current of the hybrid energy storage system; and then, determining the reactive compensation power of the energy storage battery according to the reference current of the energy storage battery.

It can be understood that, unlike the conventional control strategy, the overall power of the hybrid energy storage system is divided into an average power and an instantaneous power during the variation of the load and the power generation amount of the hybrid energy storage system, and then the power balance equation of the hybrid energy storage system can be expressed as:

in the formula (I), the compound is shown in the specification,P_l(t)、P_ren(t)、P_b(t)、P_sc(t) respectively representing load power, photovoltaic power generation power, battery power and super capacitor power in the hybrid energy storage system,andmean power and instantaneous power are indicated separately.

In order to keep the dc link voltage in the hybrid energy storage system within a certain level, the net power required to be provided by the hybrid energy storage system is:

in the formula (I), the compound is shown in the specification,andrespectively representing average and instantaneous power, V_dcIs a DC link voltage i_totRepresents the total current of the hybrid energy storage system, and t is time.

In order to enable the dc link voltage in the hybrid energy storage system to remain constant, the total current provided by the hybrid energy storage system can be expressed as follows:

in the formula (I), the compound is shown in the specification,andrespectively representing average and instantaneous power, V_dcIs a voltage of the direct current link and,which represents the average current of the current flowing through the current collector,representing the instantaneous current, t is time.

As a preferred embodiment, the above steps: a process for obtaining a total current for a hybrid energy storage system, comprising:

acquiring the total current of the hybrid energy storage system according to the current mathematical model;

wherein, the expression of the current mathematical model is as follows:

i_tot(t)＝K_{p_vdc}v_er+K_{i_vdc}∫v_erdt；

in the formula i_totIs the total current of the hybrid energy storage system, K_{p_vdc}And K_{i_vdc}Proportional constant and integral constant, v, of the voltage control loop in the hybrid energy storage system_erTo the fault voltage, t is time.

Specifically, in the embodiment, when the total current of the hybrid energy storage system is obtained, the total current of the hybrid energy storage system may be obtained from a voltage control loop of the hybrid energy storage system. That is, the total current of the hybrid energy storage system is obtained according to the current mathematical model.

As a preferred embodiment, the above steps: the process of obtaining the reference current of the energy storage battery according to the total current of the hybrid energy storage system comprises the following steps:

acquiring a reference current of the energy storage battery according to the total current of the hybrid energy storage system based on a target mathematical model;

wherein, the expression of the target mathematical model is as follows:

in the formula i_brefFor reference current of energy storage cell, omega_cFor hybrid energy storage systemsCut-off frequency of the medium low-pass filter, s is Laplace transform factor, i_totIs the total current of the hybrid energy storage system.

In a conventional hybrid energy storage system control strategy, a low pass filter in the hybrid energy storage system is used to derive a total current i from the energy storage hybrid system_totIn which case the average current of the hybrid energy storage systemIt can be calculated according to the following formula:

in the formula i_brefFor reference current, omega, controlled by a battery converter in a hybrid energy storage system_cFor the cut-off frequency of the low-pass filter in the hybrid energy storage system, s represents the laplace transform factor.

As can be seen from the above formula, in this embodiment, the reference current i of the energy storage battery can be calculated according to the target mathematical model_bref. It should be noted that the target mathematical model needs to be calculated under the laplace transform.

As a preferred embodiment, the above steps: the process of determining reactive compensation power according to a reference current of an energy storage battery comprises the following steps:

determining reactive compensation power according to the reference current of the energy storage battery based on the power compensation model;

wherein, the expression of the power compensation model is as follows:

P_{b_uncomp}(s)＝(i_bref(s)-i_b(s))v_b(s)

in the formula, P_{b_uncomp}For reactive compensation of power, i_brefFor reference current of energy storage cell, i_bIs the actual current of the energy storage cell, v_bS is the laplace transform factor, which is the voltage of the energy storage battery.

It is understood that in practical applications, the cut-off frequency of the low pass filter in the hybrid energy storage system is 10 π rad/sec, and the average current in the hybrid energy storage system is controlled by the energy storage battery. Because dynamic changes of the battery, the battery controller and the bidirectional DC-DC converter in the hybrid energy storage system are very slow, the reactive compensation power of the energy storage battery can be obtained by observation, namely:

P_{b_uncomp}(s)＝(i_bref(s)-i_b(s))v_b(s)

in the formula, P_{b_uncomp}For reactive compensation of power, i_brefFor reference current of energy storage cell, i_bIs the actual current of the energy storage cell, v_bS is the laplace transform factor, which is the voltage of the energy storage battery.

Obviously, by calculating the reactive compensation power of the energy storage battery by the method provided by the embodiment, the reactive compensation power of the energy storage battery can be more accurately and reliably obtained.

Based on the above embodiments, this embodiment further describes and optimizes the technical solution, and as a preferred implementation, the above steps: the process of feeding back reactive compensation power to a super capacitor of a hybrid energy storage system to control the hybrid energy storage system comprises the following steps:

obtaining reactive compensation current of the energy storage battery by using the reactive compensation power, and obtaining instantaneous effective current of the energy storage battery;

and jointly acting the reactive compensation current of the energy storage battery, the instantaneous effective current of the energy storage battery and the actual current of the super capacitor to the super capacitor so as to control the hybrid energy storage system.

In this embodiment, in the process of feeding back the reactive compensation power of the energy storage battery to the super capacitor of the hybrid energy storage system, it is necessary to obtain the reactive compensation current of the energy storage battery by using the reactive compensation power, and obtain the instantaneous effective current of the energy storage battery, and then jointly apply the reactive compensation current of the energy storage battery, the instantaneous effective current of the energy storage battery and the actual current of the super capacitor to the super capacitor of the hybrid energy storage system to control the hybrid energy storage system.

The expression of the instantaneous effective current of the energy storage battery is as follows:

in the formula (I), the compound is shown in the specification,for instantaneous effective current, omega, of energy-storage cells_cIs the cut-off frequency of a low-pass filter in the hybrid energy storage system, s is a Laplace transform factor, i_totIs the total current of the hybrid energy storage system.

The expression of the reactive compensation current of the energy storage battery is as follows:

in the formula i_scref(s) is the reactive compensation current of the energy storage battery,for instantaneous effective current of energy-storage battery, i_b(s) is the current of the energy storage cell, v_b(s) is the voltage of the energy storage cell, v_sc(s) is the voltage of the supercapacitor.

Referring to fig. 2, fig. 2 is a schematic diagram illustrating a hybrid energy storage system controlled by reactive compensation power of an energy storage battery according to an embodiment of the present invention. In fig. 2, PI represents a PI (Proportional Integral) controller, LPF represents a low pass filter in the hybrid energy storage system, and v in the dashed box_b/v_scDenotes a correction coefficient, v_refRepresenting the reference voltage, V, of a hybrid energy storage system_dcFor the DC link voltage i_totRepresents the total current of the hybrid energy storage system,Represents the average current,Representing instantaneous current, i_bFor the actual current, i, of the energy storage cell_{b_err}For fault currents, i, of energy storage cells_brefFor reference current, i, of energy storage cell_scIs the current of the supercapacitor, d_scIs the DC current of the super capacitor_b、sw_c、sw_dAnd sw_eAre all control switches of a DC-DC converter in the hybrid energy storage system. Wherein, the control switch sw_bAnd sw_cEnergy storage battery for controlling hybrid energy storage system and control switch sw_dAnd sw_eFor controlling a supercapacitor in a hybrid energy storage system.

Obviously, by the technical scheme provided by the embodiment, the current tracking error in the hybrid energy storage system can be reduced, and the direct-current link voltage in the hybrid energy storage system can be quickly recovered.

Referring to fig. 3, fig. 3 is a structural diagram of a control device of a hybrid energy storage system according to an embodiment of the present invention, where the control device includes:

the power obtaining module 21 is configured to obtain reactive compensation power of an energy storage battery in the hybrid energy storage system;

and the system control module 22 is used for feeding back the reactive compensation power to the super capacitor of the hybrid energy storage system so as to control the hybrid energy storage system.

The control device of the hybrid energy storage system provided by the embodiment of the invention has the beneficial effects of the control method of the hybrid energy storage system disclosed in the foregoing.

Referring to fig. 4, fig. 4 is a structural diagram of a control device of a hybrid energy storage system according to an embodiment of the present invention, where the control device includes:

a memory 31 for storing a computer program;

a processor 32 for implementing the steps of a method of controlling a hybrid energy storage system as disclosed in the foregoing when executing a computer program.

The control device of the hybrid energy storage system provided by the embodiment of the invention has the beneficial effects of the control method of the hybrid energy storage system disclosed in the foregoing.

Accordingly, the present invention also discloses a computer readable storage medium, on which a computer program is stored, which, when being executed by a processor, implements the steps of the control method of the hybrid energy storage system as disclosed in the foregoing.

The computer-readable storage medium provided by the embodiment of the invention has the beneficial effects of the control method of the hybrid energy storage system disclosed in the foregoing.

The embodiments are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same or similar parts among the embodiments are referred to each other. The device disclosed by the embodiment corresponds to the method disclosed by the embodiment, so that the description is simple, and the relevant points can be referred to the method part for description.

Finally, it should also be noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.

The above detailed description is provided for the control method, apparatus, device and medium of the hybrid energy storage system, and the specific examples are applied herein to explain the principle and implementation of the present invention, and the description of the above embodiments is only used to help understanding the method and the core idea of the present invention; meanwhile, for a person skilled in the art, according to the idea of the present invention, there may be variations in the specific embodiments and the application scope, and in summary, the content of the present specification should not be construed as a limitation to the present invention.