Power control method, electronic device, computer storage medium and energy storage system

Abstract

The present invention discloses a power control method, an electronic device, a computer storage medium and an energy storage system, wherein the power control method comprises: obtaining the output power value and battery charge state of an adjacent energy storage converter, wherein the adjacent energy storage converter is an energy storage converter that performs limited communication with a target energy storage converter; and performing power correction on the target energy storage converter according to the output power value and the battery charge state. The method can be used to perform power compensation on the energy storage converter through limited communication to improve the rationality of the output power distribution of each energy storage converter, improve the overall benefit of the energy storage system, reduce the communication cost of the energy storage system, and accelerate the convergence rate of the output power.

Description

Technical Field

[0001] The present invention relates to the technical field of energy storage systems, and in particular to a power control method, electronic equipment, computer storage medium and energy storage system. Background Art

[0002] With the transformation of the global energy structure, renewable energy has received widespread attention and application. However, the randomness and intermittency of renewable energy have brought challenges to the stability of the power grid. In order to meet these challenges, energy storage systems are widely used to improve the consumption of renewable energy and the stability of the power grid. How to coordinate the output power of each energy storage inverter in the energy storage system has become an urgent problem to be solved. At present, when controlling the output power of each energy storage inverter, the output power of each energy storage inverter is allocated through the data of all energy storage inverters in the energy storage system. However, the allocation method has the problem of unreasonable output power allocation of each energy storage inverter, which reduces the overall benefit of the energy storage system. Summary of the invention

[0003] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, one purpose of the present invention is to propose a power control method, which can be used to perform power compensation on energy storage converters through limited communication to improve the rationality of output power distribution of each energy storage converter, improve the overall efficiency of the energy storage system, reduce the communication cost of the energy storage system, and accelerate the convergence rate of output power.

[0004] A second objective of the present invention is to provide an electronic device.

[0005] A third object of the present invention is to provide a computer storage medium.

[0006] A fourth object of the present invention is to provide a computer program product.

[0007] A fifth object of the present invention is to provide an energy storage system.

[0008] In order to solve the above problems, an embodiment of the first aspect of the present invention provides a power control method, including: obtaining the output power value and battery charge state of an adjacent energy storage inverter, wherein the adjacent energy storage inverter is an energy storage inverter that performs limited communication with a target energy storage inverter; and performing power correction on the target energy storage inverter according to the output power value and the battery charge state.

[0009] According to the power control method of the embodiment of the present invention, based on the communication mode of limited communication between the target energy storage inverter and the adjacent energy storage inverter, when allocating output power to the target energy storage inverter, the target energy storage inverter is power-corrected by the output power value and battery charge state of the adjacent energy storage inverter. Therefore, compared with the existing energy storage system that allocates the output power of each energy storage inverter by the data of all energy storage inverters, each energy storage inverter in the present application allocates the output power of each energy storage inverter by the data of its limitedly communicated adjacent energy storage inverters, so that each energy storage inverter improves the rationality of the output power allocation of each energy storage inverter without obtaining the data of all energy storage inverters, significantly improves the overall performance of the energy storage system, enhances the stability and efficiency of the energy storage system, reduces the communication cost of the energy storage system, and accelerates the convergence rate of the output power.

[0010] In some embodiments, power correction is performed on the target energy storage inverter according to the output power value and the battery state of charge, including: obtaining the actual active power value, initial active power value and actual state of charge of the target energy storage inverter; obtaining the power impact factor of each adjacent energy storage inverter on the target energy storage inverter; obtaining the power compensation value of the target energy storage inverter according to the output power value, the battery state of charge, the actual active power value, the actual state of charge and the power impact factor; and correcting the initial active power value according to the power compensation value to obtain the final active power value to be output by the target energy storage inverter.

[0011] In some embodiments, the final active power value is obtained by the following formula:

[0012] ,

[0013] ,

[0014] Among them, P ref.i is the final active power value of the target energy storage converter, P ref.i0 is the initial active power value of the target energy storage converter, P 补 is the power compensation value, P i is the actual active power value of the target energy storage converter, SOC i is the actual state of charge of the target energy storage converter, SOC j is the battery charge state of the adjacent energy storage converter, k ij is the power impact factor, P j is the output power value of the jth adjacent energy storage converter, is the number of adjacent energy storage converters.

[0015] In some embodiments, the method also includes: obtaining the actual reactive power value and reactive power reference value of the target energy storage converter; based on the virtual synchronous machine, calculating and obtaining a pulse control signal for controlling the operation of the target energy storage converter according to the final active power value, the actual active power value, the actual reactive power value and the reactive power reference value.

[0016] In some embodiments, based on the virtual synchronous machine, a pulse control signal for controlling the operation of the target energy storage converter is calculated according to the final active power value, the actual active power value, the actual reactive power value and the reactive power reference value, including: obtaining the actual electromotive force amplitude of the virtual synchronous machine according to the actual reactive power value and the reactive power reference value; obtaining the control output angular frequency of the virtual synchronous machine by calculating the motor rotor motion equation of the virtual synchronous machine according to the final active power value and the actual active power value; and performing voltage and current dual-loop control according to the actual electromotive force amplitude and the control output angular frequency to obtain the pulse control signal.

[0017] In some embodiments, voltage-current dual-loop control is performed according to the actual electromotive force amplitude and the control output angular frequency to obtain the pulse control signal, including: performing voltage loop control according to the actual electromotive force amplitude and the control output angular frequency to obtain a d-axis current reference value and a q-axis current reference value; performing current loop control according to the control output angular frequency, the d-axis current reference value and the q-axis current reference value to obtain a d-axis voltage reference value and a q-axis voltage reference value; performing coordinate transformation according to the d-axis voltage reference value and the q-axis voltage reference value to obtain a three-phase AC voltage value; and obtaining the pulse control signal according to the three-phase AC voltage value.

[0018] In some embodiments, voltage loop control is performed according to the actual electromotive force amplitude and the control output angular frequency to obtain a d-axis current reference value and a q-axis current reference value, including: obtaining a voltage loop proportional coefficient and a voltage loop integral coefficient, and obtaining a virtual impedance value and a filter capacitance value at the output end of the target energy storage converter; and obtaining the d-axis current reference value and the q-axis current reference value through a voltage loop control equation according to the actual electromotive force amplitude, the control output angular frequency, the voltage loop proportional coefficient, the voltage loop integral coefficient, the virtual impedance value and the filter capacitance value.

[0019] In some embodiments, current loop control is performed according to the control output angular frequency, the d-axis current reference value, and the q-axis current reference value to obtain a d-axis voltage reference value and a q-axis voltage reference value, including: obtaining a current loop proportional coefficient and a current loop integral coefficient, and obtaining a filter inductance value at the output end of the target energy storage converter; obtaining a d-axis voltage reference value and a q-axis voltage reference value through a current loop control equation according to the d-axis current reference value, the q-axis current reference value, the control output angular frequency, the filter inductance value, the current loop proportional coefficient, and the current loop integral coefficient.

[0020] In some embodiments, obtaining the pulse control signal according to the three-phase AC voltage value includes: comparing the three-phase AC voltage value with a triangular carrier to generate the pulse control signal.

[0021] In some embodiments, obtaining the actual active power value and the actual reactive power value of the target energy storage converter includes: obtaining three-phase current data and three-phase voltage data on the AC bus to which the target energy storage converter is connected; performing coordinate transformation according to the three-phase current data and the three-phase voltage data to obtain the actual reactive power value and the actual active power value.

[0022] A second aspect of the present invention provides an electronic device, comprising: at least one processor; a memory communicatively connected to at least one of the processors; wherein the memory stores a computer program executable by at least one of the processors, and when at least one of the processors executes the computer program, the power control method described in the above embodiment is implemented.

[0023] According to the electronic device of the embodiment of the present invention, by executing the power control method of the above embodiment, the energy storage inverter can be power compensated through limited communication to improve the rationality of the output power distribution of each energy storage inverter, improve the overall efficiency of the energy storage system, reduce the communication cost of the energy storage system, and accelerate the convergence rate of the output power.

[0024] A third aspect of the present invention provides a computer storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the power control method described in the above embodiment.

[0025] A fourth aspect of the present invention provides a computer program product, including a computer program, wherein the computer program implements the steps of the method described in the above embodiment when executed by a processor.

[0026] A fifth aspect of the present invention provides an energy storage system, comprising: an energy storage converter; and a controller, wherein the controller is connected to the energy storage converter and is used to execute the power control method described in the above embodiment.

[0027] According to the energy storage system of the embodiment of the present invention, by executing the power control method of the above embodiment, power compensation can be performed on the energy storage inverter through limited communication to improve the rationality of the output power distribution of each energy storage inverter, improve the overall efficiency of the energy storage system, reduce the communication cost of the energy storage system, and accelerate the convergence rate of the output power.

[0028] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0030] Figure 1 is a flow chart of a power control method according to an embodiment of the present invention;

[0031] Figure 2 is a schematic diagram of limited communication of multiple energy storage converters according to an embodiment of the present invention;

[0032] Figure 3 is a schematic diagram of a power control process according to an embodiment of the present invention;

[0033] Figure 4 It is a schematic diagram of the output power change of the energy storage converter in the prior art;

[0034] Figure 5 is a schematic diagram of output power variation of an energy storage converter according to an embodiment of the present invention;

[0035] Figure 6 is a structural block diagram of an electronic device according to an embodiment of the present invention;

[0036] Figure 7 is a structural block diagram of an energy storage system according to an embodiment of the present invention.

[0037] Reference numerals:

[0038] Energy storage system 20; electronic device 10;

[0039] Processor 1; memory 2; energy storage converter 3; controller 4; AC bus 5; filter resistor R f ; Filter inductor L; Filter capacitor C; Load Z. DETAILED DESCRIPTION

[0040] Embodiments of the present invention are described in detail below. The embodiments described with reference to the accompanying drawings are exemplary. Embodiments of the present invention are described in detail below.

[0041] In order to solve the above problems, the first aspect of the embodiment of the present invention provides a power control method, which can be used to perform power compensation on the energy storage inverter through limited communication, so as to improve the rationality of the output power distribution of each energy storage inverter, improve the overall efficiency of the energy storage system, reduce the communication cost of the energy storage system, and accelerate the convergence rate of the output power.

[0042] Reference below Figure 1 The power control method according to the embodiment of the present invention is described as follows: Figure 1 As shown, the method includes: step S1 to step S2.

[0043] Step S1, obtaining an output power value and a battery charge state of an adjacent energy storage converter, wherein the adjacent energy storage converter is an energy storage converter that performs limited communication with a target energy storage converter.

[0044] Among them, the energy storage converter (Power Conversion System, PCS) can control the charging and discharging process of the battery, perform AC-DC conversion, and can directly supply power to the AC load without a power grid. The energy storage converter can have a variety of topological structures, the common ones are three-phase two-level converter, NPC (Neutral Point Clamped, diode midpoint clamped) three-phase three-level converter, T-type three-phase three-level converter, three-phase cascade multi-level converter, etc., and there is no restriction on this. The battery charge state is the ratio of the remaining capacity of the battery managed by the adjacent energy storage converter after a period of use or long-term shelving to its fully charged capacity.

[0045] In the embodiment, limited communication refers to the target energy storage converter communicating with a limited number of adjacent energy storage converters, that is, building a distributed communication network, and enabling each energy storage converter to communicate with a limited number of adjacent energy storage converters, without requiring each energy storage converter to communicate with other energy storage converters. This communication method not only reduces the communication cost, but also improves the scalability of the system. The number of adjacent energy storage converters can be 1, 2 or 3, and there is no restriction on comparison. In addition, the number of adjacent energy storage converters is less than the total number of energy storage converters in the energy storage system.

[0046] Specifically, the output power value and battery charge state of the adjacent energy storage converter that performs limited communication with the target energy storage converter are obtained, for example, Figure 2 As shown, the energy storage converter PCS2 is the target energy storage converter, and the target energy storage converter PCS2 only communicates with the energy storage converter PCS1 and the energy storage converter PCS3. Then the energy storage converter PCS1 and the energy storage converter PCS3 are the adjacent energy storage converters of the target energy storage converter PCS2, and the output power values ​​and battery charge states of the adjacent energy storage converter PCS1 and the adjacent energy storage converter PCS3 are obtained.

[0047] Step S2, performing power correction on the target energy storage converter according to the output power value and the battery charge state.

[0048] Specifically, in order to solve this problem, in the present application, the output power of each energy storage inverter is power corrected by the output power value and battery state of charge of the adjacent energy storage inverter. That is to say, when each energy storage inverter in the energy storage system is used as the target energy storage inverter for power correction, since the output power of the target energy storage inverter is power corrected by the output power value and battery state of charge of the adjacent energy storage inverter, the adjacent energy storage inverter of the target energy storage inverter will also perform power correction on its output power by the output power value and battery state of charge of its adjacent energy storage inverter when it is used as another target energy storage inverter for power correction. That is to say, when the target energy storage inverter is power corrected, the power correction will be performed by the output power value and battery state of charge of the adjacent energy storage inverter after the power correction, and there is no need to obtain the data of the non-adjacent energy storage inverters of the target energy storage inverter. By analogy, when the power correction is performed on each energy storage inverter, the output power of the target energy storage inverter is indirectly corrected by the output power value and battery state of charge of the adjacent energy storage inverter. The output power values ​​of the remaining energy storage converters in the energy storage system and the battery charge state are used for power correction to realize the automatic distribution of the output power of each energy storage converter in the energy storage system, so that the target energy storage converter can realize the rapid and reasonable distribution of the output power of each energy storage converter without obtaining all the energy storage converter data. Therefore, compared with the existing energy storage system that distributes the output power of each energy storage converter through the data of all the energy storage converters, each energy storage converter in this application distributes the output power of each energy storage converter through the data of its limited communication adjacent energy storage converter, so that each energy storage converter can improve the rationality of the output power distribution of each energy storage converter without obtaining all the energy storage converter data, so as to significantly improve the overall performance of the energy storage system by optimizing the output power of each energy storage converter, enhance the stability and efficiency of the energy storage system, reduce the loss and failure risk of the energy storage system, reduce the communication cost of the energy storage system, and accelerate the convergence rate of the output power. In addition, the power control method in this application is applicable to both grid-connected and off-grid situations, and has strong versatility and practicality.

[0049] Exemplarily, the energy storage system includes three energy storage converters, such as Figure 2As shown, when the energy storage converter PCS1 is used as the target energy storage converter, the adjacent energy storage converter of the energy storage converter PCS1 is PCS2, and the power of the energy storage converter PCS1 is corrected by the output power value and battery charge state of the adjacent energy storage converter PCS2. When the adjacent energy storage converter PCS2 is used as the target energy storage converter, the adjacent energy storage converter of the adjacent energy storage converter PCS2 is PCS3, and the power of the energy storage converter PCS2 is corrected by the output power value and battery charge state of the adjacent energy storage converter PCS3, that is, when the power of the energy storage converter PCS1 is corrected, the power of the energy storage converter PCS3 is corrected. After the power of energy storage converter PCS2 is corrected by the data of energy storage converter PCS2, the power of energy storage converter PCS1 is corrected by the data of energy storage converter PCS2. That is to say, the power of energy storage converter PCS1 is corrected by the output power value and battery charge state of energy storage converter PCS2 and energy storage converter PCS2, and energy storage converter PCS1 does not need to obtain the data of non-adjacent energy storage converter PCS3. Therefore, each energy storage converter performs power correction through the data of adjacent energy storage converters obtained by limited communication, thereby indirectly performing power correction on each energy storage converter through the data of all energy storage converters in the energy storage system.

[0050] According to the power control method of the embodiment of the present invention, based on the communication mode of limited communication between the target energy storage inverter and the adjacent energy storage inverter, when allocating output power to the target energy storage inverter, the target energy storage inverter is power-corrected by the output power value and battery charge state of the adjacent energy storage inverter. Therefore, compared with the existing energy storage system that allocates the output power of each energy storage inverter by the data of all energy storage inverters, each energy storage inverter in the present application allocates the output power of each energy storage inverter by the data of its limitedly communicated adjacent energy storage inverters, so that each energy storage inverter improves the rationality of the output power allocation of each energy storage inverter without obtaining the data of all energy storage inverters, significantly improves the overall performance of the energy storage system, enhances the stability and efficiency of the energy storage system, reduces the communication cost of the energy storage system, and accelerates the convergence rate of the output power.

[0051] In some embodiments, the target energy storage converter is power-corrected according to the output power value and the battery state of charge, including: obtaining the actual active power value, the initial active power value and the actual state of charge of the target energy storage converter; obtaining the power influence factor of each adjacent energy storage converter on the target energy storage converter; obtaining the power compensation value of the target energy storage converter according to the output power value, the battery state of charge, the actual active power value, the actual state of charge and the power influence factor; and correcting the initial active power value according to the power compensation value to obtain the final active power value to be output by the target energy storage converter. That is to say, Figure 3 As shown, through the output power value Pj , Battery State of Charge SOC j , actual active power value P i , actual state of charge SOC i and P ref_0 That is, the initial active power value P ref.i0 , to calculate the final active power value P ref.i .

[0052] In some embodiments, the final active power value is obtained by the following formula:

[0053] (1),

[0054] (2),

[0055] Among them, P ref.i is the final active power value of the target energy storage converter, P ref.i0 is the initial active power value of the target energy storage converter, P 补 is the power compensation value, P i is the actual active power value of the target energy storage converter, SOC i is the actual state of charge of the target energy storage converter, SOC j is the battery charge state of the adjacent energy storage converter, k ij is the power impact factor, P j is the output power value of the jth adjacent energy storage converter, is the number of adjacent energy storage converters.

[0056] Specifically, obtain the actual active power value P of the target energy storage converter i , initial active power value P ref.i0 and actual state of charge SOC i , and obtain the power impact factor k of each adjacent energy storage converter on the target energy storage converter ij , and obtain the output power value P j and battery state of charge SOC j , then the output power value P j , Battery State of Charge SOC j , actual active power value P i , actual state of charge SOC i and power influence factor k ij Substitute into formula (2) to calculate the power compensation value P of the target energy storage converter 补 .

[0057] Then the initial active power value P is adjusted by the power compensation value ref.i0Correction is performed, that is, the sum of the overpower compensation value and the initial active power value is calculated to obtain the final active power value P that the target energy storage converter needs to output ref.i The power compensation value P 补 and the initial active power value P ref.i0 Substitute into formula (1) to calculate the final active power value P ref.i .

[0058] For example, Figure 4 As shown in the figure, the power changes of the three energy storage converters (PCS1, PCS2, PCS3) without power compensation value for output power compensation are shown in the figure. Figure 4 It can be seen that when the virtual impedance is inconsistent with the actual line impedance, there is a deviation in the output power of each energy storage converter, and the output power of the energy storage converter converges slowly. The output power distribution of each energy storage converter is uneven, which will cause some energy storage converters to be overloaded or underloaded. Figure 5 As shown, the power change of the three energy storage converters (PCS1, PCS2, PCS3) after the power compensation value of the present application is used to compensate the output power, that is, the final active power value. The three energy storage converters communicate with each other in a limited manner. Figure 5 It can be seen that the output power distribution of each energy storage converter is more reasonable, the convergence speed of the output power is accelerated, and the overall performance of the energy storage system is significantly improved.

[0059] Therefore, in the present application, the target energy storage converter obtains the corrected final active power value through the power compensation value, that is, the final active power value is used as the output power of the target energy storage converter, so that the output power distribution of the energy storage converter is more reasonable, and the convergence speed of the output power is accelerated, and the overall performance of the energy storage system is significantly improved.

[0060] In some embodiments, the actual reactive power value and reactive power reference value of the target energy storage converter are obtained; based on a virtual synchronous generator (VSG), a pulse control signal for controlling the operation of the target energy storage converter is calculated according to the final active power value, the actual active power value, the actual reactive power value and the reactive power reference value.

[0061] Specifically, the energy storage converter adopts virtual synchronous machine control based on virtual resistance, and compensates the line impedance through virtual impedance to simulate the operating characteristics of the synchronous generator. That is to say, the virtual synchronous machine is based on the final active power value P ref.i , actual active power value P i , actual reactive power value Q m and reactive power reference value Q ref, in order to calculate the pulse control signal g for controlling the operation of the target energy storage converter. Thus, the pulse control signal is obtained through the virtual synchronous machine, which can improve the response speed and stability of the energy storage converter, thereby enhancing the performance of the energy storage system, and the energy storage converter has the ability to seamlessly switch between grid-connected and off-grid.

[0062] In some embodiments, based on the virtual synchronous machine, a pulse control signal for controlling the operation of the target energy storage converter is calculated according to the final active power value, the actual active power value, the actual reactive power value and the reactive power reference value, including: calculating the actual electromotive force amplitude of the virtual synchronous machine according to the actual reactive power value Q and the reactive power reference value; the virtual synchronous machine calculates the actual electromotive force amplitude of the virtual synchronous machine according to the actual reactive power value Q m and reactive power reference value Q ref The actual electromotive force amplitude E of the virtual synchronous machine is calculated; the control output angular frequency of the virtual synchronous machine is calculated according to the final active power value and the actual active power value through the motor rotor motion equation of the virtual synchronous machine, such as Figure 3 As shown, the final active power value P ref.i And the actual active power value P i The virtual synchronous machine is input to calculate the control output angular frequency ω; the voltage and current dual loop control is performed according to the actual electromotive force amplitude E and the control output angular frequency ω to obtain the pulse control signal g.

[0063] In the embodiment, a virtual synchronous machine is used to control the output characteristics of the simulated synchronous generator, and the virtual synchronous machine rotor motion equation is:

[0064] (3),

[0065] (4),

[0066] Among them, E is the actual electromotive force amplitude, Q ref is the reactive power reference value, Q m is the actual reactive power value, n is the reactive power adjustment coefficient, E ref is the virtual electromotive force reference value, ω is the control output angular frequency, P ref.i is the final active power value, P i is the actual active power value, J is the virtual inertia coefficient, D is the virtual damping coefficient, ω n is the rated angular frequency. In addition, in order to avoid a large excitation surge current during startup, E ref It should be gradually increased from 0 to the rated value within a certain period of time after the virtual synchronous machine is started. n In a 50Hz system it is 100π.

[0067] Specifically, the actual reactive power value Q m and reactive power reference value Qref Substitute into formula (3) to calculate the actual electromotive force amplitude E of the virtual synchronous machine, that is, the actual electromotive force amplitude of the virtual synchronous machine is calculated by the reactive power-voltage equation, and the final active power value P ref.i And the actual active power value P i Substitute the motor rotor motion equation (4) of the virtual synchronous machine to calculate the control output angular frequency ω of the virtual synchronous machine. Based on this, the voltage and current dual-loop control is performed according to the actual electromotive force amplitude E and the control output angular frequency ω to obtain the pulse control signal g, wherein the voltage and current dual-loop control can be an outer loop voltage control and an inner loop current control, the control quantity output by the outer loop controller is a voltage reference value, and the control quantity output by the inner loop controller is a current reference value. The pulse control signal is used to control the switch of the target energy storage converter. The pulse control signal can be a PWM signal, and then the switch action of the target energy storage converter is driven by the pulse control signal to change the waveform of the output current and power supply of the target energy storage converter, thereby controlling the final active power value output by the target energy storage converter.

[0068] In some embodiments, voltage and current dual loop control is performed according to the actual electromotive force amplitude and the control output angular frequency to obtain a pulse control signal, including: performing voltage loop control according to the actual electromotive force amplitude and the control output angular frequency to obtain a d-axis current reference value and a q-axis current reference value; performing current loop control according to the control output angular frequency, the d-axis current reference value and the q-axis current reference value to obtain a d-axis voltage reference value and a q-axis voltage reference value; performing coordinate transformation according to the d-axis voltage reference value and the q-axis voltage reference value to obtain a three-phase AC voltage value; and obtaining a pulse control signal according to the three-phase AC voltage value. Figure 3 As shown, according to the d-axis voltage reference value V ref_d and q-axis voltage reference value V ref_q Perform (DQ / ABC) coordinate transformation to obtain the three-phase AC voltage value V ref_abc ; According to the three-phase AC voltage value V ref_abc A pulse control signal g is obtained, thereby controlling the switching action of the target energy storage converter through the pulse control signal g.

[0069] (5),

[0070] Among them, V ref_d is the d-axis voltage reference value, V ref_q is the q-axis voltage reference value, θ is the virtual synchronous machine control output angle, V ref_a is the A phase AC voltage value, V ref_b is the AC voltage value of phase B, V ref_c is the C phase AC voltage value.

[0071] Specifically, voltage loop control is performed according to the actual electromotive force amplitude and the control output angular frequency to obtain the d-axis current reference value and the q-axis current reference value, and then current loop control is performed according to the control output angular frequency, the d-axis current reference value and the q-axis current reference value to obtain the d-axis voltage reference value V ref_d and q-axis voltage reference value V ref_q , and then the d-axis voltage reference value V ref_d and q-axis voltage reference value V ref_q Substitute into the change formula (5) to perform coordinate transformation, that is, convert the two-phase DC quantity into the three-phase AC quantity to calculate the three-phase AC voltage value, where the three-phase AC voltage value includes V ref_a 、V ref_b and V ref_c , based on this, a pulse control signal is obtained according to the three-phase AC voltage value, so as to drive the switching action of the target energy storage converter through the pulse control signal, so as to control the target energy storage converter to output the final active power value through energy change.

[0072] In some embodiments, voltage loop control is performed according to the actual electromotive force amplitude and the control output angular frequency to obtain a d-axis current reference value and a q-axis current reference value, including: obtaining a voltage loop proportional coefficient and a voltage loop integral coefficient, and obtaining a virtual impedance value and a filter capacitance value at the output end of a target energy storage converter; and obtaining a d-axis current reference value and a q-axis current reference value through a voltage loop control equation according to the actual electromotive force amplitude, the control output angular frequency, the voltage loop proportional coefficient, the voltage loop integral coefficient, the virtual impedance value and the filter capacitance value.

[0073] In an embodiment, Figure 3 As shown, the energy storage converter 3 is connected in sequence with a filter resistor R f , filter inductor L and filter capacitor C, and the AC bus 5 is connected to a load Z.

[0074] (6),

[0075] Among them, I ref_d is the d-axis current reference value, I ref_q is the q-axis current reference value, k up is the voltage loop proportional coefficient, k ui is the voltage loop integral coefficient, L v is the virtual impedance value, C f is the filter capacitor value, E is the actual electromotive force amplitude, ω is the control output angular frequency, U d is the d-axis voltage measurement value, U q is the q-axis voltage measurement value, S is the differential operator, I d is the d-axis current measurement value, I q is the q-axis current measurement value.

[0076] Specifically, the actual electromotive force amplitude E, the control output angular frequency ω, and the voltage loop proportional coefficient k up , voltage loop integration coefficient k ui , virtual impedance value L v , filter capacitor value C f , d-axis current measurement value I d , q-axis current measurement value I q , d-axis voltage measurement value U d and the q-axis voltage measurement value U q Substitute into formula (6), the voltage loop control equation, to calculate the d-axis current reference value I ref_d and q-axis current reference value I ref_q .

[0077] In some embodiments, current loop control is performed according to the control output angular frequency, d-axis current reference value and q-axis current reference value to obtain d-axis voltage reference value and q-axis voltage reference value, including: obtaining the current loop proportional coefficient and the current loop integral coefficient, and obtaining the filter inductance value at the output end of the target energy storage converter; obtaining the d-axis voltage reference value and the q-axis voltage reference value through the current loop control equation according to the d-axis current reference value, the q-axis current reference value, the control output angular frequency, the filter inductance value, the current loop proportional coefficient and the current loop integral coefficient.

[0078] (7),

[0079] Among them, V ref_d is the d-axis voltage reference value, V ref_q is the q-axis voltage reference value, k ip is the current loop proportionality coefficient, k ii is the current loop integral coefficient, S is the differential operator, I d is the d-axis current measurement value, I q is the q-axis current measurement value, ω is the control output angular frequency, L f is the filter inductance value, U d is the d-axis voltage measurement value, U q is the q-axis voltage measurement value.

[0080] Specifically, the d-axis current reference value I ref_d , q-axis current reference value I ref_q , control output angular frequency ω, filter inductance value L f , current loop proportionality coefficient k ip , current loop integral coefficient k ii , d-axis current measurement value I d , q-axis current measurement value I q , d-axis voltage measurement value U d and the q-axis voltage measurement value U qSubstitute into formula (7) the current loop control equation to calculate the d-axis voltage reference value V ref_d and q-axis voltage reference value V ref_q .

[0081] In some embodiments, a pulse control signal is obtained according to a three-phase AC voltage value, including: comparing the three-phase AC voltage value with a triangular carrier to generate a pulse control signal g, that is, generating a pulse control signal through the comparison result of the three-phase AC voltage value and the triangular carrier, wherein the comparison result may be that the three-phase AC voltage value is greater than the triangular carrier, or the three-phase AC voltage value is less than the triangular carrier, thereby driving the switching action of the target energy storage inverter through the pulse control signal to control the target energy storage inverter to output a final active power value through energy changes, thereby achieving precise control of the output voltage, frequency, and output power of the target energy storage inverter.

[0082] In some embodiments, obtaining the actual active power value and the actual reactive power value of the target energy storage converter includes: obtaining three-phase current data and three-phase voltage data on the AC bus to which the target energy storage converter is connected; performing coordinate transformation according to the three-phase current data and the three-phase voltage data to obtain the actual reactive power value and the actual active power value.

[0083] (8),

[0084] (9),

[0085] (10),

[0086] Among them, θ is the virtual synchronous machine control output angle, U a is the phase voltage of phase A, U b is the phase voltage of phase B, U c is the phase voltage of phase C, U d is the d-axis voltage measurement value, U q is the q-axis voltage measurement value, I a is the current value of phase A, I b is the current value of phase B, I c is the current value of phase C, I d is the d-axis current measurement value, I q is the q-axis current measurement value, P i is the actual active power value, Q m is the actual reactive power value.

[0087] Specifically, Figure 3As shown, a voltage sensor VT and a current sensor CT are provided on the AC bus 5. The voltage sensor is used to collect three-phase voltage data Ug_abc, and the current sensor is used to collect three-phase current data Ig_abc. The three-phase voltage data includes U a , U b and U c , three-phase current data includes I a ,I b and I c , coordinate transformation is performed based on the three-phase current data and the three-phase voltage data to obtain the actual reactive power value Q m And the actual active power value P i First, the three-phase current data is transformed by the conversion formula (8), and the three-phase voltage data is transformed by the conversion formula (9), that is, the voltage and current values ​​of phase A, phase B and phase C are transformed to obtain the two-phase current data I g_dq And two-phase voltage data U g_dq , where the two-phase current data includes I d and I q , two-phase voltage data including U d and U q Then, by substituting the two-phase current data and the two-phase voltage data into the power calculation formula (10), the actual reactive power value Q is calculated. m And the actual active power value P i .

[0088] A second aspect of the present invention provides an electronic device, such as Figure 6 As shown, the electronic device 10 includes: at least one processor 1 and a memory 2 communicatively connected to the at least one processor 1 .

[0089] The memory 2 stores a computer program executable by at least one processor 1, and the power control method of the above embodiment is implemented when the at least one processor 1 executes the computer program. The electronic device can be a device independent of the energy storage converter, or a device arranged in the energy storage converter.

[0090] It should be noted that the specific implementation method of the electronic device of the embodiment of the present invention is similar to the specific implementation method of the power control method of any of the above embodiments of the present invention. Please refer to the description of the method part for details. In order to reduce redundancy, it will not be repeated here.

[0091] According to the electronic device of the embodiment of the present invention, by executing the power control method of the above embodiment, the energy storage inverter can be power compensated through limited communication to improve the rationality of the output power distribution of each energy storage inverter, improve the overall efficiency of the energy storage system, reduce the communication cost of the energy storage system, and accelerate the convergence rate of the output power.

[0092] A third aspect of the present invention provides a computer storage medium having a computer program stored thereon, wherein the computer program implements the power control method of the above embodiment when executed by a processor.

[0093] A fourth aspect of the present invention provides a computer program product, including a computer program, wherein the computer program implements the steps of the method described in the above embodiment when executed by a processor.

[0094] A fifth aspect of the present invention provides an energy storage system 20, such as Figure 7 As shown, the energy storage system 20 includes: an energy storage converter 3 and a controller 4 .

[0095] The controller 4 is connected to the energy storage converter 3 and is used to execute the power control method of the above embodiment. There are multiple energy storage converters 3, and a distributed communication network is constructed by multiple energy storage converters 3. Each energy storage converter can communicate with a limited number of adjacent energy storage converters. The energy storage system can be a distributed energy storage system.

[0096] It should be noted that the specific implementation of the energy storage system of the embodiment of the present invention is similar to the specific implementation of the power control method of any of the above embodiments of the present invention. Please refer to the description of the method part for details. In order to reduce redundancy, it will not be repeated here.

[0097] According to the energy storage system of the embodiment of the present invention, by executing the power control method of the above embodiment, power compensation can be performed on the energy storage inverter through limited communication to improve the rationality of the output power distribution of each energy storage inverter, improve the overall efficiency of the energy storage system, reduce the communication cost of the energy storage system, and accelerate the convergence rate of the output power.

[0098] In the description of this specification, any process or method description in a flowchart or otherwise described herein may be understood to represent a module, fragment or portion of code including one or more executable instructions for implementing the steps of a custom logical function or process, and the scope of the preferred embodiments of the present invention includes alternative implementations in which functions may not be performed in the order shown or discussed, including performing functions in a substantially simultaneous manner or in reverse order depending on the functions involved, which should be understood by technicians in the technical field to which the embodiments of the present invention belong.

[0099] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as an ordered list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by an instruction execution system, device or apparatus (such as a computer-based system, a system including a processor, or other system that can fetch instructions from an instruction execution system, device or apparatus and execute instructions), or in combination with these instruction execution systems, devices or apparatuses. For the purposes of this specification, "computer-readable medium" can be any device that can contain, store, communicate, propagate or transmit a program for use by an instruction execution system, device or apparatus, or in combination with these instruction execution systems, devices or apparatuses. More specific examples (non-exhaustive list) of computer-readable media include the following: an electrical connection with one or more wires (electronic device), a portable computer disk box (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable and programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disk read-only memory (CDROM). In addition, the computer-readable medium may even be paper or other suitable medium on which the program is printed, since the program may be obtained electronically, for example, by optically scanning the paper or other medium and then editing, interpreting or processing in other suitable ways if necessary, and then stored in a computer memory.

[0100] It should be understood that the various parts of the present invention can be implemented by hardware, software, firmware or a combination thereof. In the above-mentioned embodiments, multiple steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or their combination: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0101] A person skilled in the art may understand that all or part of the steps in the method for implementing the above-mentioned embodiment may be completed by instructing related hardware through a program, and the program may be stored in a computer-readable storage medium, which, when executed, includes one or a combination of the steps of the method embodiment.

[0102] In addition, each functional unit in each embodiment of the present invention may be integrated into a processing module, or each unit may exist physically separately, or two or more units may be integrated into one module. The above-mentioned integrated module may be implemented in the form of hardware or in the form of a software functional module. If the integrated module is implemented in the form of a software functional module and sold or used as an independent product, it may also be stored in a computer-readable storage medium.

[0103] The storage medium mentioned above may be a read-only memory, a magnetic disk or an optical disk, etc. Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limiting the present invention. A person of ordinary skill in the art may change, modify, replace and modify the above embodiments within the scope of the present invention.

[0104] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example.

[0105] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A power control method, characterized in that: include: Acquire an output power value and a battery charge state of an adjacent energy storage converter, wherein the adjacent energy storage converter is an energy storage converter that performs limited communication with the target energy storage converter; Performing power correction on the target energy storage converter according to the output power value and the battery state of charge; The power correction of the target energy storage converter is performed according to the output power value and the battery state of charge, including: Obtaining an actual active power value, an initial active power value, and an actual state of charge of the target energy storage converter; Obtaining a power impact factor of each adjacent energy storage converter on the target energy storage converter; Obtaining a power compensation value of the target energy storage converter according to the output power value, the battery state of charge, the actual active power value, the actual state of charge and the power impact factor; The initial active power value is corrected according to the power compensation value to obtain a final active power value that the target energy storage converter needs to output.

2. The power control method according to claim 1, characterized in that: The final active power value is obtained by the following formula: Among them, P ref.i is the final active power value of the target energy storage converter, P ref.i0 is the initial active power value of the target energy storage converter, is the power compensation value, P i is the actual active power value of the target energy storage converter, SOC i is the actual state of charge of the target energy storage converter, SOC j is the battery charge state of the adjacent energy storage converter, k ij is the power impact factor, P j is the output power value of the jth adjacent energy storage converter, is the number of adjacent energy storage converters.

3. The power control method according to claim 1 or 2, characterized in that: The method further comprises: Obtaining an actual reactive power value and a reactive power reference value of the target energy storage converter; Based on the virtual synchronous machine, a pulse control signal for controlling the operation of the target energy storage converter is calculated according to the final active power value, the actual active power value, the actual reactive power value and the reactive power reference value.

4. The power control method according to claim 3, characterized in that: Based on the virtual synchronous machine, a pulse control signal for controlling the operation of the target energy storage converter is calculated according to the final active power value, the actual active power value, the actual reactive power value and the reactive power reference value, including: Calculate the actual electromotive force amplitude of the virtual synchronous machine according to the actual reactive power value and the reactive power reference value; Calculating the control output angular frequency of the virtual synchronous machine according to the final active power value and the actual active power value through the motor rotor motion equation of the virtual synchronous machine; The pulse control signal is obtained by performing voltage and current dual-loop control according to the actual electromotive force amplitude and the control output angular frequency.

5. The power control method according to claim 4, characterized in that: Performing voltage and current dual-loop control according to the actual electromotive force amplitude and the control output angular frequency to obtain the pulse control signal includes: Performing voltage loop control according to the actual electromotive force amplitude and the control output angular frequency to obtain a d-axis current reference value and a q-axis current reference value; Performing current loop control according to the control output angular frequency, the d-axis current reference value, and the q-axis current reference value to obtain a d-axis voltage reference value and a q-axis voltage reference value; Performing coordinate transformation according to the d-axis voltage reference value and the q-axis voltage reference value to obtain a three-phase AC voltage value; The pulse control signal is obtained according to the three-phase AC voltage value.

6. The power control method according to claim 5, characterized in that: Performing voltage loop control according to the actual electromotive force amplitude and the control output angular frequency to obtain a d-axis current reference value and a q-axis current reference value includes: Obtaining a voltage loop proportional coefficient and a voltage loop integral coefficient, and obtaining a virtual impedance value and a filter capacitance value at the output end of the target energy storage converter; The d-axis current reference value and the q-axis current reference value are obtained through a voltage loop control equation according to the actual electromotive force amplitude, the control output angular frequency, the voltage loop proportional coefficient, the voltage loop integral coefficient, the virtual impedance value and the filter capacitance value.

7. The power control method according to claim 5 or 6, characterized in that: Performing current loop control according to the control output angular frequency, the d-axis current reference value, and the q-axis current reference value to obtain a d-axis voltage reference value and a q-axis voltage reference value, comprising: Obtaining a current loop proportional coefficient and a current loop integral coefficient, and obtaining a filter inductance value at an output end of the target energy storage converter; The d-axis voltage reference value and the q-axis voltage reference value are obtained through the current loop control equation according to the d-axis current reference value, the q-axis current reference value, the control output angular frequency, the filter inductance value, the current loop proportional coefficient and the current loop integral coefficient.

8. The power control method according to claim 5, characterized in that: Obtaining the pulse control signal according to the three-phase AC voltage value includes: The three-phase AC voltage value is compared with a triangular carrier to generate the pulse control signal.

9. The power control method according to claim 3, characterized in that: Obtaining the actual active power value and the actual reactive power value of the target energy storage converter includes: Acquire three-phase current data and three-phase voltage data on the AC bus to which the target energy storage converter is connected; Coordinate transformation is performed according to the three-phase current data and the three-phase voltage data to obtain the actual reactive power value and the actual active power value.

10. An electronic device, characterized in that: include: at least one processor; a memory communicatively coupled to at least one of the processors; The memory stores a computer program executable by at least one of the processors, and when at least one of the processors executes the computer program, the power control method according to any one of claims 1 to 9 is implemented.

11. A computer storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the power control method according to any one of claims 1 to 9 is implemented.

12. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the steps of the power control method according to any one of claims 1 to 9 are implemented.

13. An energy storage system, characterized in that: include: Energy storage converter; A controller, wherein the controller is connected to the energy storage converter and is used to execute the power control method according to any one of claims 1 to 9.

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