Active power control optimization method for energy storage system

Abstract

The invention relates to an active power control optimization method for an energy storage system, and the method mainly achieves the control parameter setting and active power coordination control of a new energy storage system under different operation conditions, so as to achieve the limiting of the active power adjustment rate during the normal charging and discharging operation of the energy storage system, and guarantee the stable operation of a power grid. And under the working conditions of primary frequency modulation, emergency power control and the like, rapid adjustment is realized to provide support for a power grid. According to the method, the problems that the active power regulation rate of the current new energy storage system cannot adapt to automatic regulation of operation conditions and power coordination control among different operation conditions is incomplete are solved.

Description

Technical Field

[0001] The present invention relates to the field of new energy storage system access and control technology, and in particular to an energy storage system active power control optimization method. Background Art

[0002] Due to the fast regulation rate of energy storage, in order to ensure the safe operation of the power grid, the power grid organization requires that the regulation rate of the active power of the energy storage power station charging and discharging be limited under normal operating conditions. For example, during the power control capability test planned by a certain energy storage power station in the Southern Power Grid, the active power of the energy storage power station changed rapidly within the range of plus or minus 200MW, causing the active power of the AC outlet of a southern province and the deviation of the opposite end to jump too much instantly, triggering the AGC (automatic generation control) anti-error strategy, causing the AGC to suspend control for a short time, causing a large disturbance to the safe operation of the system. At the same time, under special conditions such as primary frequency regulation and emergency power control, the energy storage system needs to respond quickly to provide support for the power grid. At present, the energy storage system for new energy applications basically only sets a set of active power regulation parameters in the PCS main control program, and can only respond to a single operating condition at the same time scale. In addition, the PMS also lacks different operating condition judgment strategies and different operating condition active power coordination control strategies. The innovation of the present invention is to adjust the active power control parameters of different operating conditions in PCS, and to add judgment and coordination control strategies of different operating conditions in PMS. Through the coordinated cooperation of PMS and PCS, the problem that the current new energy storage system has only one set of active power control parameters in PCS, cannot automatically adjust the control parameters to adapt to different operating conditions such as normal operation, primary frequency modulation, emergency power support, and cannot coordinate the control of power commands between different operating conditions is solved. Summary of the invention

[0003] In order to solve the above problems, the present invention proposes an active power control optimization method for energy storage systems. This method uses the active power control parameters of different operating conditions to be set in the PCS, and adds the judgment and coordination control strategies of different operating conditions in the PMS. Through the coordinated cooperation between the PMS and the PCS, the new energy storage system can automatically adjust the control parameters to adapt to different operating conditions such as normal operation, primary frequency regulation, and emergency power support, and at the same time, coordinate the cross-coordination between different operating conditions.

[0004] The present invention is implemented in this way: while the active power regulation rate limit is maintained during normal charging and discharging operation of the energy storage power station, the active power regulation rate is not limited under the working conditions of primary frequency modulation, emergency power control, etc. It is necessary to optimize and adapt the power control strategy of the energy storage collaborative control system (Power Management System, PMS) and the energy storage converter (Power Convertion System, PCS) control system.

[0005] The specific method is as follows:

[0006] Step 1: Distinguish the working conditions of the energy storage device in the energy storage power station: ① Normal operation, the charge and discharge rate is less than 50Pn% / min, Pn is the rated power of the energy storage; ② Primary frequency modulation control, the energy storage system primary frequency modulation lag time is not more than 1s, the primary frequency modulation rise time is not more than 3s, and the primary frequency modulation adjustment time is not more than 4s; ③ When the electrochemical energy storage is used for emergency power support, the maximum dischargeable or rechargeable power is reached within 200ms;

[0007] Step 2: The state signal of the PMS during normal power regulation is recorded as N. First, two state signal points are added to the PMS: a frequency regulation action signal, which is triggered by whether the frequency change of the grid-connected point sampled by the PMS exceeds the frequency regulation dead zone, and its state signal is recorded as F; and an emergency power support signal, which is the received external signal, synthesized by signals such as grid faults and overload, and its state signal is recorded as S; the two state signal points realize the reliable transmission of real-time signal information between the PMS and the PCS through the general object-oriented substation event GOOSE communication protocol in the IEC 61850 communication protocol;

[0008] Step 3: Active power control with grid voltage directional loss is adopted. First, the current command is obtained by preprocessing the power command, and then the PI regulator is used to perform closed-loop control on the current. At the same time, the feedforward link decouples the d-axis current and q-axis current obtained after Clark coordinate transformation of the three-phase current. The current control loop can be simplified to a second-order system. Let K i / K p =R / L eliminates the low-frequency pole introduced by the resistance and inductance to optimize the system dynamic performance, and the closed-loop output of the current control loop is obtained as:

[0009]

[0010] in:

[0011]

[0012] K p is the proportionality coefficient, K i is the integral coefficient, R is the system resistance, L is the system inductance, ζ is the second-order system damping ratio, ω n is the undamped natural oscillation angular frequency. According to the time domain response of the second-order system and ω n The relationship between the system response speed and stability is adjusted to design the PI parameters of PCS (i.e., K p With K i ), store 3 groups of active power control current loops (i.e. K Ni / K NP , K Fi / KFP , K Si / K SP ), the control effect of each group of PI parameters meets the corresponding state condition requirements in step 1;

[0013] Step 4: PCS receives and stores the power instructions of the three working conditions respectively, and comprehensively judges different energy storage operating conditions according to the remote adjustment power instructions and remote signal issued by PMS, so as to call different PI parameters for charging and discharging power control; when F = S = 0, the first working condition in step 1 adopts the method of PMS decomposing power instructions and sending them to PCS for gradual adjustment according to the different adjustment rates of the energy storage system required, or PMS directly sends power instructions and PCS decomposes instructions for gradual execution. Substituting formula (1) into it, the power instruction executed by PCS during normal operation power adjustment is as follows:

[0014]

[0015] Formula (3) represents the rounding function; I0 is the initial current value; ΔI is the adjustment step, which is automatically calculated by the system after the adjustment rate parameter configuration is modified in the system; m is the round number of the multi-round instruction, P ref Indicates the power command, I ref Indicates current instruction;

[0016] Step 5: When F=1, S=0, the power command increment of the second working condition in step 1 is calculated by PMS according to formula (5). The power command executed by PCS during the primary frequency modulation is as shown in formula (6):

[0017]

[0018] Where: ΔP t K is the change in active power of the energy storage system; t is the active frequency modulation coefficient; Δf is the power system frequency deviation; f N is the rated frequency of the power system, unit: Hz; P t is the active power of the energy storage system.

[0019]

[0020] Step 6: When F=0, S=1, the power command for the third working condition in step 1 is issued by the PMS according to the direction of the required power support, and the full power charge / discharge command is executed by the PCS. The power command executed by the PCS is as follows:

[0021]

[0022] Step 7: When two or more of the three operating conditions described in step 1 are triggered simultaneously, the PMS increases the power command coordination logic strategy issued.

[0023] Furthermore, the primary frequency modulation lag time described in step 1 is the time from when the system frequency exceeds the frequency modulation dead zone to when the actual output active power change of the electrochemical energy storage system reaches 10% of the difference between the active target value and the initial value.

[0024] Furthermore, the primary frequency modulation rise time described in step 1 is the time from when the system frequency exceeds the frequency modulation dead zone to when the actual output active power change of the electrochemical energy storage power station reaches 90% of the difference between the active target value and the initial value.

[0025] Furthermore, the frequency regulation time described in step 1 is the shortest time from when the system frequency exceeds the frequency regulation dead zone to when the absolute value of the difference between the measured active power output value and the active power target value of the electrochemical energy storage power station does not exceed 2% of the difference between the active power target value and the initial value.

[0026] Further, in step 7, when two or more of the three working conditions described in step 1 are triggered at the same time, the PMS increases the power command coordination logic strategy issued as follows:

[0027] When S=1, only the emergency power support command of formula (7) is executed, and the PMS locks the primary frequency modulation and normal power regulation command;

[0028] When S=0, F=1, N=1, the coordination relationship between primary frequency modulation and normal power regulation is divided into the following five types. Each mode is realized by the PMS program function. Only one coordination mode can be put into use at the same time. ① Same direction superposition, reverse blocking normal regulation: When the primary frequency modulation and normal regulation instructions are in the same direction, the PCS executes the power instruction as the algebraic sum of the normal regulation amount and the primary frequency modulation response regulation amount. At the same time, formula (6) is executed first, and formula (4) is executed later. When the primary frequency modulation and normal regulation instructions are in opposite directions, the PMS blocks the normal regulation instruction and the PCS executes the power instruction of formula (6); ② Same direction superposition, reverse blocking primary frequency modulation: Primary frequency modulation and normal regulation When the command directions are the same, the power command executed by PCS is the algebraic sum of the normal adjustment amount and the primary frequency modulation response adjustment amount, and at the same time, it gives priority to executing formula (6) and then executing formula (4). When the directions of the primary frequency modulation and the normal adjustment command are opposite, PMS blocks the primary frequency modulation command and PCS executes the power command of formula (4); ③ Command superposition: The power command executed by PCS is the algebraic sum of the normal adjustment amount and the primary frequency modulation response adjustment amount, and at the same time, it gives priority to executing formula (6) and then executing formula (4). ④ Normal adjustment priority: PMS blocks the primary frequency modulation command and PCS executes the power command of formula (4); ⑤ Primary frequency modulation priority, PMS blocks the normal adjustment command and PCS executes the power command of formula (6).

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] At present, the energy storage system of new energy application basically only sets a set of active power adjustment parameters in the PCS main control program. It can only respond to a unique operating condition under the same time scale. Generally, a set of parameters with a faster adjustment rate is used to give priority to the primary frequency regulation requirements. During normal adjustment, the power command is decomposed and issued by PMS to meet the rate limit requirements. Due to communication delay and other reasons, the instructions decomposed by PMS cannot be very small, resulting in the adjustment effect of this method being step-type and not smooth enough; at the same time, PMS also lacks different operating condition judgment strategies and different operating condition active power coordination control strategies, and some increase the cost by adding an additional primary frequency regulation device to achieve coordinated control. The present invention sets the active power control parameters of different operating conditions in the PCS main control to adapt to different adjustment rates, avoids the problem of communication delay, and the adjustment effect is close to the ramp type during normal adjustment, and the adjustment effect is smooth and effective in controlling the rate. At the same time, through the coordinated cooperation of PMS and PCS, the current new energy storage system cannot adapt well to different operating conditions such as normal operation, primary frequency regulation, emergency power support, etc. to automatically adjust the control parameters and cannot coordinate the power command between different operating conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a vector control block diagram of the three-phase three-wire energy storage PCS of the present invention directed by the grid voltage;

[0032] Figure 2 It is a simplified control block diagram of the current loop of the present invention;

[0033] Figure 3 It is a flow chart for implementing the present invention. DETAILED DESCRIPTION

[0034] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention is further described in detail below in conjunction with embodiment.It will be appreciated by those skilled in the art that, unless otherwise defined, all terms (including technical terms and scientific terms) used herein have the same meaning as the general understanding of those of ordinary skill in the field to which the present invention belongs.It will be appreciated by those skilled in the art that the following examples are only used to illustrate the present invention and should not be considered as limiting the scope of the present invention.In the embodiment, those who do not indicate specific techniques or conditions are carried out according to the techniques or conditions described in the literature in this area or according to the product specification.Reagents used or instruments that do not indicate manufacturers are conventional products that can be obtained by purchase.

[0035] Example:

[0036] A method for optimizing active power control of an energy storage system. The method uses active power control parameters of different operating conditions to be set in PCS, adds judgment and coordination control strategies of different operating conditions in PMS, and realizes automatic adjustment of control parameters of the new energy storage system to adapt to different operating conditions such as normal operation, primary frequency regulation, and emergency power support through the coordinated cooperation of PMS and PCS. At the same time, cross-coordinated control is carried out between different operating conditions.

[0037] While the active power regulation rate is limited during normal charging and discharging operation of the energy storage power station, the active power regulation rate is not limited under primary frequency regulation, emergency power control and other working conditions. It is necessary to optimize and adapt the power control strategy of the energy storage collaborative control system PMS and the energy storage converter PCS control system. The specific methods are as follows:

[0038] Step 1: Distinguish the working conditions of the energy storage device into: ① Normal operation, satisfying the charge and discharge rate is less than 50Pn% / min (Pn is the rated power of the energy storage, the value can be set); ② Primary frequency modulation control, which must meet the requirements that the primary frequency modulation lag time of the energy storage system (the time from the system frequency exceeding the frequency modulation dead zone to the time when the actual output active power change of the electrochemical energy storage system reaches 10% of the difference between the active target value and the initial value) is no more than 1s, the primary frequency modulation rise time (the time from the system frequency exceeding the frequency modulation dead zone to the time when the actual output active power change of the electrochemical energy storage power station reaches 90% of the difference between the active target value and the initial value) is no more than 3s, and the primary frequency modulation adjustment time (the shortest time from the system frequency exceeding the frequency modulation dead zone to the absolute value of the difference between the actual measured value of the active power output of the electrochemical energy storage power station and the active target value always does not exceed 2% of the difference between the active target value and the initial value) is no more than 4s; ③ When the electrochemical energy storage is used for emergency power support, the maximum dischargeable or rechargeable power is reached within 200ms.

[0039] Step 2: When the PMS is operating normally and adjusting power, the state signal is recorded as N. First, two state signal points are added to the PMS, namely, the primary frequency regulation action signal (triggered by whether the frequency change of the grid-connected point sampled by the PMS exceeds the frequency regulation dead zone), the state signal is recorded as F; and the emergency power support signal (received external signal, synthesized by grid fault and overload signals, etc.), the state signal is recorded as S; the two state signal points realize the reliable transmission of real-time signal information between the PMS and the PCS through the Generic Object Oriented Substation Event (GOOSE) communication protocol in IEC 61850.

[0040] Step 3: The simplified block diagram of active power control using grid voltage directional vector is as follows: Figure 1As shown. First, the current command is obtained by preprocessing the power command, and then the PI regulator is used to perform closed-loop control on the current. At the same time, the feedforward link decouples the d-axis current and the q-axis current. The current control loop can be simplified as Figure 2 For the second-order system shown in Figure 1, let K i / K p =R / L eliminates the low-frequency pole introduced by the resistance and inductance to optimize the system dynamic performance, and the closed-loop output of the current control loop is obtained as:

[0041]

[0042] in:

[0043]

[0044] ζ is the damping ratio of the second-order system, ω n is the undamped natural oscillation angular frequency. According to the time domain response of the second-order system and ω n The relationship between ζ and ζ is adjusted between the rapidity of system response and stability, and the PI parameters of PCS are designed. Three groups of active power control current loop PI parameters need to be stored in the PCS main control program, and the control effect of each group of PI parameters meets the requirements in step 1;

[0045] Step 4: PCS receives and stores the power instructions of the three working conditions respectively, and comprehensively judges the different energy storage operating conditions according to the remote adjustment power instructions and remote signal issued by PMS to call different PI parameters for charging and discharging power control. When F=S=0, the first working condition in step 1 has different adjustment rates of the energy storage system according to the requirements. It can be adopted that the PMS decomposes the power instruction and sends it to the PCS for gradual adjustment, or the PMS directly sends the power instruction and the PCS decomposes the instruction and gradually executes it. The power instruction executed by the PCS is as follows:

[0046]

[0047] Wherein, formula (3) represents the floor function; I0 is the initial value of the current; ΔI is the adjustment step, which is automatically calculated by the system after the adjustment rate parameter configuration is modified in the system; m is the round number of the multi-round instruction.

[0048] Step 5: When F=1, S=0, the power command increment of the second working condition in step 1 is calculated by the PMS according to formula (5), and the power command executed by the PCS is as follows:

[0049]

[0050] Where: ΔP t K is the change in active power of the energy storage system; t is the active frequency modulation coefficient; Δf is the power system frequency deviation; fN is the rated frequency of the power system, unit: Hz; f is the grid connection point frequency; P t is the active power of the energy storage system.

[0051]

[0052] Step 6: When F=0, S=1, the power command for the third working condition in step 1 is issued by the PMS according to the direction of the required power support, and the full power charge / discharge command is executed by the PCS. The power command executed by the PCS is as follows:

[0053]

[0054] Step 7: When two or more of the three working conditions described in step 1 are triggered simultaneously, the PMS increases the power command coordination logic strategy as follows:

[0055] When S=1, only the emergency power support command of formula (7) is executed, and the PMS locks the primary frequency modulation and normal power regulation command;

[0056] When S=0, F=1, and N=1, the coordination relationship between primary frequency modulation and normal power regulation is divided into the following five types. Each mode is implemented by the PMS program function. Only one coordination mode can be put into use at the same time. ① Same-direction superposition and reverse blocking of normal regulation: When the primary frequency modulation and normal regulation instructions are in the same direction, the power instruction executed by the PCS is the algebraic sum of the normal regulation amount and the primary frequency modulation response regulation amount, and at the same time, formula (6) is executed first, and formula (4) is executed later. When the primary frequency modulation and normal regulation instructions are in opposite directions, the PMS blocks the normal regulation instruction, and the PCS executes the power instruction of formula (6); ② Same-direction superposition and reverse blocking of primary frequency modulation: When the primary frequency modulation and normal regulation instructions are in the same direction, the power instruction executed by the PCS is the algebraic sum of the normal regulation amount and the primary frequency modulation response regulation amount, and at the same time, formula (6) is executed first, and formula (4) is executed later. When the primary frequency modulation is in the opposite direction to the normal adjustment command, the PMS blocks the primary frequency modulation command and the PCS executes the power command of formula (4); ③ Command superposition: The power command executed by the PCS is the algebraic sum of the normal adjustment amount and the primary frequency modulation response adjustment amount, and the formula (6) is executed at the same time, and the formula (4) is executed later. ④ Normal adjustment priority: The PMS blocks the primary frequency modulation command and the PCS executes the power command of formula (4); ⑤ Primary frequency modulation priority, the PMS blocks the normal adjustment command and the PCS executes the power command of formula (6).

[0057] like Figure 1 As shown, the three-phase voltage U is collected from the PCS main circuit through the sampling circuit abc and current i abcThe system phase angle is input into the PCS main controller (such as a DSP digital signal processing chip). The sampling signal is first transformed by Clark to obtain the d-axis and q-axis components, and then subtracted from the current command calculated by the execution power command of the PCS in the embodiment. The deviation is subjected to feedforward decoupling and PI control algorithm to obtain a voltage reference value. The voltage reference value is subjected to coordinate inverse transformation to generate a modulation signal, and then a modulation algorithm (such as SPWM sinusoidal pulse width modulation, SVPMW voltage space vector modulation, etc.) is used to generate the driving waveform required for the operation of the switching device IGBT (insulated gate bipolar transistor) in the PCS, and finally the command power is output to complete the closed-loop control.

[0058] Application examples:

[0059] A new energy storage station is equipped with a 10MW / 20MWh energy storage system. Set the power control PI parameters for emergency power support, primary frequency regulation, and normal regulation for call. Define the energy storage power symbol "-" for charging and "+" for discharging, and define the instruction P. The numbers in the following table represent the instruction rounds, and the letters represent the adjustment parameters for the execution of the instructions in this round. Set the initial current value I0 to 0; the ΔI adjustment step is 5%I n ; K t The active frequency regulation coefficient is 100; Δf is the power system frequency deviation of +0.15Hz, then the power increment calculated after frequency regulation is -3MW. The normal regulation power command is set to +1MW. Table 1 shows the typical results of this example.

[0060] Table 1

[0061]

[0062] The above shows and describes the basic principles, main features and advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments, and the above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention to be protected. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A method for optimizing active power control of an energy storage system, characterized in that: Follow these steps: Step 1: Distinguish the working conditions of the energy storage device in the energy storage power station: ① Normal operation, the charge and discharge rate is less than 50Pn% / min, Pn is the rated power of the energy storage; ② Primary frequency modulation control, the energy storage system primary frequency modulation lag time is not more than 1s, the primary frequency modulation rise time is not more than 3s, and the primary frequency modulation adjustment time is not more than 4s; ③ When the electrochemical energy storage is used for emergency power support, the maximum dischargeable or rechargeable power is reached within 200ms; Step 2: The state signal of the PMS during normal power regulation is recorded as N. First, two state signal points are added to the PMS: a frequency regulation action signal, which is triggered by whether the frequency change of the grid-connected point sampled by the PMS exceeds the frequency regulation dead zone, and its state signal is recorded as F; and an emergency power support signal, which is the received external signal, synthesized by signals such as grid faults and overload, and its state signal is recorded as S; the two state signal points realize the reliable transmission of real-time signal information between the PMS and the PCS through the general object-oriented substation event GOOSE communication protocol in the IEC 61850 communication protocol; Step 3: Active power control with grid voltage directional loss is adopted. First, the current command is obtained by preprocessing the power command, and then the PI regulator is used to perform closed-loop control on the current. At the same time, the feedforward link decouples the d-axis current and q-axis current obtained after Clark coordinate transformation of the three-phase current. The current control loop can be simplified to a second-order system. Let K i / K p =R / L eliminates the low-frequency pole introduced by the resistance and inductance to optimize the system dynamic performance, and the closed-loop output of the current control loop is obtained as: in: K p is the proportionality coefficient, K i is the integral coefficient, R is the system resistance, L is the system inductance, ζ is the second-order system damping ratio, ω n is the undamped natural oscillation angular frequency. According to the time domain response of the second-order system and ω n The relationship between ζ and system response speed and stability is adjusted to design the PI parameter K of PCS. p With K i , store 3 groups of active power control current loops, namely K in the PCS main control program Ni / K NP , K Fi / K FP , K Si / K SP , the control effect of each group of PI parameters meets the corresponding state condition requirements in step 1; Step 4: PCS receives and stores the power instructions of the three working conditions respectively, and comprehensively judges different energy storage operating conditions according to the remote adjustment power instructions and remote signal issued by PMS, so as to call different PI parameters for charging and discharging power control; when F = S = 0, the first working condition in step 1 adopts the method of PMS decomposing power instructions and sending them to PCS for gradual adjustment according to the different adjustment rates of the energy storage system required, or PMS directly sends power instructions and PCS decomposes instructions for gradual execution. Substituting formula (1) into it, the power instruction executed by PCS during normal operation power adjustment is as follows: Formula (3) represents the rounding function; I0 is the initial current value; ΔI is the adjustment step, which is automatically calculated by the system after the adjustment rate parameter configuration is modified in the system; m is the round number of the multi-round instruction, P ref Indicates the power command, I ref Indicates current instruction; Step 5: When F=1, S=0, the power command increment of the second working condition in step 1 is calculated by PMS according to formula (5). The power command executed by PCS during the primary frequency modulation is as shown in formula (6): Where: ΔP t K is the change in active power of the energy storage system; t is the active frequency modulation coefficient; Δf is the power system frequency deviation; f N is the rated frequency of the power system, unit: Hz; P t is the active power of the energy storage system. Step 6: When F=0, S=1, the power command for the third working condition in step 1 is issued by the PMS according to the direction of the required power support, and the full power charge / discharge command is executed by the PCS. The power command executed by the PCS is as follows: Step 7: When two or more of the three operating conditions described in step 1 are triggered simultaneously, the PMS increases the power command coordination logic strategy issued.

2. The method for optimizing active power control of an energy storage system according to claim 1, characterized in that: The primary frequency modulation lag time described in step 1 is the time required from the system frequency exceeding the frequency modulation dead zone to the actual output active power change of the electrochemical energy storage system reaching 10% of the difference between the active target value and the initial value.

3. The method for optimizing active power control of an energy storage system according to claim 1, characterized in that: The primary frequency modulation rise time described in step 1 is the time required from the system frequency exceeding the frequency modulation dead zone to the actual output active power change of the electrochemical energy storage power station reaching 90% of the difference between the active target value and the initial value.

4. The method for optimizing active power control of an energy storage system according to claim 1, characterized in that: The frequency regulation time described in step 1 is the shortest time from when the system frequency exceeds the frequency regulation dead zone to when the absolute value of the difference between the measured active power output value of the electrochemical energy storage power station and the active power target value never exceeds 2% of the difference between the active power target value and the initial value.

5. The method for optimizing active power control of an energy storage system according to claim 1, characterized in that: In step 7, when two or more of the three working conditions described in step 1 are triggered at the same time, the PMS increases the power command coordination logic strategy issued as follows: When S=1, only the emergency power support command of formula (7) is executed, and the PMS locks the primary frequency modulation and normal power regulation command; When S=0, F=1, N=1, the coordination relationship between primary frequency modulation and normal power regulation is divided into the following five types. Each mode is realized by the PMS program function. Only one coordination mode can be put into use at the same time. ① Same direction superposition, reverse blocking normal regulation: When the primary frequency modulation and normal regulation instructions are in the same direction, the PCS executes the power instruction as the algebraic sum of the normal regulation amount and the primary frequency modulation response regulation amount. At the same time, formula (6) is executed first, and formula (4) is executed later. When the primary frequency modulation and normal regulation instructions are in opposite directions, the PMS blocks the normal regulation instruction and the PCS executes the power instruction of formula (6); ② Same direction superposition, reverse blocking primary frequency modulation: Primary frequency modulation and normal regulation When the command directions are the same, the power command executed by PCS is the algebraic sum of the normal adjustment amount and the primary frequency modulation response adjustment amount, and at the same time, it gives priority to executing formula (6) and then executing formula (4). When the directions of the primary frequency modulation and the normal adjustment command are opposite, PMS blocks the primary frequency modulation command and PCS executes the power command of formula (4); ③ Command superposition: The power command executed by PCS is the algebraic sum of the normal adjustment amount and the primary frequency modulation response adjustment amount, and at the same time, it gives priority to executing formula (6) and then executing formula (4). ④ Normal adjustment priority: PMS blocks the primary frequency modulation command and PCS executes the power command of formula (4); ⑤ Primary frequency modulation priority, PMS blocks the normal adjustment command and PCS executes the power command of formula (6).

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