A temperature control load frequency response comprehensive inertia control parameter design method

Abstract

The application provides a temperature-controlled load frequency response comprehensive inertia control parameter design method. The method comprises the following steps: a temperature-controlled load is integrated into a frequency response model of a power system by using comprehensive inertia control; a frequency response frequency domain expression of the system is obtained; a design scheme is given for response delay, droop control parameters and virtual inertia control parameters by considering the dual constraints of system frequency stability and load regulation capacity; and the design scheme has great reference significance for additional frequency response control of the temperature-controlled load.

Description

Technical Field

[0001] The present invention belongs to the technical field of power systems, and specifically relates to an application scenario of comprehensive inertia control parameter design for a temperature-controlled load cluster participating in power system frequency response. Background Art

[0002] A new power system characterized by a high proportion of renewable energy and power electronic equipment is emerging. However, this trend has led to a reduction in the capacity of traditional synchronous power sources, a decrease in inertia, and a weakening of primary frequency regulation capabilities, posing a serious challenge to grid frequency security. Academia and industry have primarily focused on inertia support for grid-connected renewable energy and grid-connected energy storage. However, the potential of the load side, particularly large-scale, distributed, and micro-loads, in providing inertial support for the power system has received less attention.

[0003] The rapid development of information communication and intelligent control technologies in recent years has provided new opportunities for clusters of temperature-controlled loads to participate in grid frequency regulation. The high bandwidth, low latency, and massive connectivity of 5G public communication networks provide critical support for the digital, networked, and intelligent transformation of power systems. This not only creates conditions for deep, two-way interaction between power supply and loads, but also enables centralized control and proactive response to grid frequency changes for large-scale temperature-controlled loads.

[0004] Utilizing open communication networks, information collection and command exchange can be achieved across a wide range of temperature-controlled loads. This foundation enables clustered power response control of massive temperature-controlled loads, enabling them to proactively provide inertial support to the power grid. This clustered frequency response control of temperature-controlled loads, based on new information and communication technologies such as 5G, will undoubtedly help alleviate the severe challenges facing frequency stability in new power systems.

[0005] The flexibility of temperature-controlled load demand response makes it suitable for use as a frequency regulation tool. Under centralized control, load clusters are uniformly managed and monitored by a central control system, either directly or indirectly through an intermediate control system. This provides high controllability and precision during regulation. However, the dynamic changes in temperature-controlled loads within the power system can significantly impact frequency stability. The simultaneous response of a large number of temperature-controlled loads can cause drastic fluctuations in system frequency, posing challenges to the safe and stable operation of the power grid.

[0006] Therefore, rationally designing the integrated inertia control parameters for the frequency response of temperature-controlled loads is crucial for improving the frequency stability of power systems. Through optimized design, temperature-controlled loads can be quickly and stably involved in frequency regulation, leveraging their flexibility to effectively support grid frequency stability. This is of great practical significance for addressing the frequency regulation pressures facing new power systems and represents a technical challenge that those skilled in the art urgently need to address. Summary of the Invention

[0007] The purpose of this invention is to propose a method for designing integrated inertial control parameters for the frequency response of temperature-controlled loads, balancing the response speed and frequency stability of temperature-controlled loads in power system frequency response. Design solutions for the integrated inertial control parameters and response delay of temperature-controlled load frequency response are provided to ensure rapid and stable regulation when frequency fluctuations occur.

[0008] To achieve the above object, the present invention adopts the following technical solutions:

[0009] A method for designing integrated inertial control parameters for a temperature-controlled load frequency response includes the following steps:

[0010] (1) Establishing a power system frequency response (SFR) control model:

[0011] a. The conventional units in the power system adopt hydropower units. The transfer function of hydropower units participating in frequency regulation is:

[0012]

[0013] The coefficients a0~a3 and b0~b4 in the formula are determined by the equivalent parameters of the single unit of the power system, the turbine and the speed control system parameters.

[0014] b. The temperature control load frequency response is integrated into the power system frequency response model using comprehensive inertia control:

[0015]

[0016] Where K vi , K dr , Δt d They are the temperature control load frequency response virtual inertia control parameters, droop control parameters and response delay.

[0017] (2) Parameter design based on power system frequency stability constraints;

[0018] a. Design of virtual inertia control parameters.

[0019] a1. Establish the system open-loop transfer function of the temperature control load frequency response virtual inertia control link:

[0020]

[0021] a2. Obtain the system amplitude-frequency characteristic A(ω) and phase-frequency characteristic

[0022]

[0023] a3. Obtain the expression of the system phase margin γ and the system cutoff frequency ω respectively. c , virtual inertia control parameter K vi , load frequency response delay Δt d Correlation with the parameter change of phase margin γ;

[0024]

[0025] a4. Based on the parameter correlation in a3, the virtual inertia control parameter K vi When it is small, the load frequency response delay will not affect the system phase margin. Solve the maximum inertia control parameter that the phase margin is not affected by the delay

[0026]

[0027] Where,

[0028] a5. Based on the parameter correlation in a3, the virtual inertia control parameter K vi As the phase angle increases gradually, the system phase margin will be affected by the delay, and there will be a response delay Δt that stabilizes the system frequency. d The maximum delay of the temperature control load response subject to phase stability constraints is:

[0029]

[0030] a6. According to the parameter correlation in a3, the virtual inertia control parameters Response delay Let the amplitude A(ω) = 1 to solve the maximum virtual inertia control parameter of the temperature control load corresponding to the current delay:

[0031]

[0032] a7. According to the parameter correlation in a3, the response delay Δt d is close to 0, and the virtual inertia control parameter constrained by the system amplitude margin stability condition is:

[0033]

[0034] b. Design of droop control parameters.

[0035] b1. Establish the system open-loop transfer function of the temperature control load frequency response to the droop control link:

[0036]

[0037] b2. Obtain the system amplitude-frequency characteristic A(ω) and phase-frequency characteristic

[0038]

[0039] b3. Obtain the expression of the system phase margin γ and the system cutoff frequency ω respectively. c , droop control parameter K dr , load frequency response delay Δt d Correlation with the parameter change of phase margin γ;

[0040] b4. Based on the parameter correlation in b3, the maximum value of the temperature-controlled load droop control parameter when the phase margin is not affected by the delay is:

[0041]

[0042] Where,

[0043] b5. According to the parameter correlation in b3, the droop control parameters The maximum delay of the temperature-controlled load response subject to phase stability constraints is solved as follows:

[0044]

[0045] b6. Response delay according to parameter correlation in b3 Let the amplitude A(ω) = 1 to solve the maximum droop control parameter of the temperature control load corresponding to the current delay:

[0046]

[0047] b7. According to the parameter correlation in b3, the response delay Δt d Close to 0, the temperature control load droop control parameters are not constrained.

[0048] c. Comprehensive inertia control parameter design.

[0049] c1. The integrated inertia control of temperature control load gives priority to meeting the system inertia requirements, and the adjustment range of virtual inertia control parameters remains unchanged. The frequency stability constraint is satisfied by adjusting the droop control parameters.

[0050] c2. Use traversal method to determine the droop control parameters. According to the reference range of droop control parameters in b, Make a downward adjustment.

[0051] (3) Parameter design under the constraints of superimposed load regulation capacity.

[0052] a. Total regulating capacity of temperature control load ΔP IAC Always meet the power system power regulation instruction requirements, The comprehensive inertia control parameters are always limited to the system frequency stability constraint range;

[0053] b. The total regulation capacity of the cluster is less than the power regulation instruction requirement of the power system, Adjust the load side comprehensive inertia control parameters;

[0054] b1. Prioritize adjusting the temperature control load droop control parameter adjustment range to meet the load cluster regulation capacity constraint;

[0055] b2. Adjust the load droop control parameter to the boundary of 0. If the load cluster regulation capacity constraint still cannot be met, adjust the virtual inertia control parameter.

[0056] The method for designing integrated inertial control parameters for the frequency response of a temperature-controlled load, provided by this invention, provides a design scheme for integrated inertial control parameters based on the dual constraints of system frequency stability and temperature-controlled load capacity. Under the frequency stability constraint, the system's amplitude and phase characteristics are used to perform preliminary parameter design, ensuring that the temperature-controlled load frequency response meets the amplitude and phase stability requirements. Under the capacity constraint, the parameter design range is ensured to optimize the system's frequency response performance while meeting the load regulation capacity. This allows the system's frequency response to better adapt to load changes, environmental changes, and other actual operating conditions, providing a more effective and stable control scheme for the temperature-controlled load frequency response of power systems. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the specific embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0058] Figure 1 A schematic diagram of an equivalent model of a temperature-controlled load participating in a power system frequency response provided by an embodiment;

[0059] Figure 2 A schematic diagram of the design range of comprehensive inertia control parameters for temperature-controlled loads under the constraints of system frequency stability provided in the embodiment;

[0060] Figure 3 Schematic diagram of the design range of comprehensive inertia control parameters for temperature-controlled loads under the dual constraints of system frequency stability and load capacity provided in the embodiment;

[0061] Figure 4 Design range curves for frequency response delay, virtual inertia control parameters, and droop control parameters of temperature-controlled load clusters;

[0062] Figure 5System frequency response curves for temperature-controlled load clusters based on different response delays, virtual inertia control parameters, and droop control parameters;

[0063] Figure 6 The actual frequency response output of the temperature-controlled load cluster under different capacity constraints and the output curve of conventional hydropower units;

[0064] Figure 7 The system frequency response curve of the temperature-controlled load cluster under different capacity constraints. DETAILED DESCRIPTION

[0065] The embodiments of the present invention are implemented based on the technical solutions and provide detailed implementation methods, but the protection scope of the present invention is not limited to the following embodiments.

[0066] The method for designing the integrated inertial control parameters of the temperature-controlled load frequency response proposed in the present invention comprises the following steps:

[0067] 1. If Figure 1 As shown, a power system frequency response (SFR) control model integrating temperature control load cluster is established:

[0068] The conventional units in the power system are hydropower units, and the transfer function of the hydropower units participating in frequency regulation is:

[0069]

[0070] The coefficients a0~a3, b0~b4 are determined by the following formula:

[0071]

[0072] Where M is the system inertia time constant. D is the system damping. w K is the time constant of water hammer effect. P , K I and K D are the proportional, integral and differential coefficients of the turbine PID governor respectively. p is the adjustment coefficient. y is the servo system time constant.

[0073] The temperature-controlled load frequency response is integrated into the power system frequency response model using comprehensive inertia control:

[0074]

[0075] Where K vi , K dr , Δt dThey are the temperature control load frequency response virtual inertia control parameters, droop control parameters and response delay.

[0076] 2. Parameter design based on power system frequency stability constraints;

[0077] (1) Design of virtual inertia control parameters.

[0078] Establish the system open-loop transfer function of the temperature control load frequency response virtual inertia control link:

[0079]

[0080] The system amplitude-frequency characteristic A(ω) is obtained:

[0081]

[0082] Amplitude margin stability condition: A(ω p )<1,ω p is the phase crossing frequency, that is, the input signal frequency corresponding to the phase of the system frequency characteristic is -π. The system amplitude-frequency characteristic is only affected by the temperature control load cluster virtual inertia control parameter K vi The impact of K vi As the value increases, the system amplitude margin decreases and the stability deteriorates.

[0083] System phase-frequency characteristics

[0084]

[0085] The expression of system phase margin γ is obtained:

[0086]

[0087] ω c is the cut-off frequency, that is, the input signal frequency corresponding to when the system amplitude-frequency characteristic crosses the 0dB line. The phase margin is only affected by the load frequency response delay Δt d The time delay increases and the phase margin decreases.

[0088] When the temperature control load virtual inertia control parameter K vi When ω is small, the system amplitude-frequency characteristic curve has no intersection with the 0dB line, and the system phase margin is infinite, that is, the temperature-controlled load frequency response delay will not cause system frequency oscillation. Using the Routh approximation method, the model W(s) of the conventional hydropower unit participating in the frequency response is reduced to second order, and the system amplitude-frequency characteristic A(ω) is set to 1. The following expression is obtained:

[0089] aω 4 +bω 2 +c=0 (25)

[0090] Where,

[0091] Equation discriminant Δ = b 2 -4ac = 0, the system amplitude-frequency characteristic curve is tangent to the 0dB line, there is a unique cut-off frequency ω c , at this time the virtual inertia control parameter is the maximum inertia control parameter unaffected by the delay. It can be obtained that:

[0092]

[0093] In the formula,

[0094] Therefore, when the virtual inertia control parameter of the temperature control load is lower than the parameter set by the following formula, the frequency stability of the system is not affected by the size of the delay. Solve the maximum inertia control parameter of the phase angle margin which is not affected by the delay

[0095]

[0096] In the formula,

[0097] With the increase of K vi , the system amplitude-frequency characteristic curve moves up, intersects with the 0dB line, there is a phase angle margin, and the frequency stability of the system will be affected by the delay, that is, there is a range of delay values that makes the system frequency stable. When the phase-frequency characteristic is , the maximum delay of the temperature control load response constrained by the phase stability is:

[0098]

[0099] Virtual inertia control parameter Response delay According to the phase-frequency characteristic, the frequency ω(Δt d ) when d is obtained, and ω(Δt d ) is substituted into the amplitude-frequency characteristic. Let the amplitude A(ω) = 1 to solve the maximum virtual inertia control parameter of the temperature control load corresponding to the current delay:

[0100] When the frequency response delay of the temperature control load is close to 0, with the increase of the frequency ω, the amplitude condition A(ω)≈K vi a3 / b4 = K vi / M, the virtual inertia control parameter constrained by the amplitude margin stability condition of the system is:

[0101]

[0102]

[0103] (2) Design of droop control parameters.

[0104] Establish the system open-loop transfer function of the temperature control load frequency response to the droop control link:

[0105]

[0106] Get the system amplitude-frequency characteristic A(ω) and phase-frequency characteristic

[0107]

[0108]

[0109] Obtain the expression of the system phase margin γ and the system cutoff frequency ω respectively c , droop control parameter K dr , load frequency response delay Δt d The correlation with the parameter change of the phase margin γ is solved; the maximum value of the temperature control load droop control parameter when the phase margin is not affected by the delay is:

[0110]

[0111] Where,

[0112] Droop control parameters The maximum delay of the temperature-controlled load response subject to phase stability constraints is solved as follows:

[0113]

[0114] Response delay Let the amplitude A(ω) = 1 to solve the maximum droop control parameter of the temperature control load corresponding to the current delay:

[0115]

[0116] Response delay Δt d Close to 0, the temperature control load droop control parameters are not constrained.

[0117] (3) Comprehensive inertia control parameter design.

[0118] When adopting comprehensive inertia control, the virtual inertia control parameters and droop control parameter range based on frequency stability adjustment may cause system frequency oscillation instability. Against the background of increasing penetration of new energy, the low inertia characteristics of the power system are significant. Therefore, the comprehensive inertia control of temperature-controlled loads gives priority to meeting the system inertia requirements, and the adjustment range of the virtual inertia control parameters remains unchanged, that is, The frequency stability constraint is satisfied by adjusting the droop control parameters.

[0119] Since the system amplitude-phase characteristics in the integrated inertia control are coupled with the integrated inertia control parameters, the phase-frequency characteristics no longer independently reflect the characteristics related to the demand response delay. Therefore, it is impossible to redefine the droop control parameters based solely on the phase-frequency characteristics. In this case, this paper adopts the ergodic method to determine the droop control parameters. According to the reference range in the previous section, Adjust the temperature control load comprehensive inertia control parameter range obtained by adjustment as follows Figure 2 shown.

[0120]

[0121] 3. Parameter design under superimposed load regulation capacity constraints.

[0122] After the power system suffers power disturbance, there are Δf(t) and f rate (t) Make the total power instruction of the temperature control load cluster reach the maximum value It can be approximately considered that the maximum value of the total power instruction of the temperature-controlled load cluster occurs at the lowest point of the system frequency. Therefore, the above expression can be simplified to:

[0123] If the total regulation capacity of the temperature control load cluster ΔP IAC Always meet the power system power regulation instruction requirements, that is, The comprehensive inertia control parameters are always limited within the system frequency stability constraint range.

[0124] If the total regulation capacity of the cluster is less than the power regulation instruction requirement of the power system, that is, The load-side integrated inertia control parameters need to be adjusted so that the power response command meets the load cluster regulation capacity constraint. The parameter adjustment rules are as follows: Figure 3 shown.

[0125] (1) Prioritize adjusting the temperature control load droop control parameter adjustment range to meet the load cluster regulation capacity constraint:

[0126]

[0127] (2) Adjust the load droop control parameter to 0. If the load cluster regulation capacity constraint is still not met, adjust the virtual inertia control parameter. In this case The adjustment range of the virtual inertia control parameter of the temperature-controlled load constrained by the load cluster adjustment capacity is:

[0128]

[0129] Considering the dual constraints of system frequency stability and load regulation capacity, the adjustment rules of the comprehensive inertia control parameters of the temperature-controlled load cluster frequency response can be summarized as follows:

[0130]

[0131] The analysis is based on the scenario where the temperature-controlled load cluster participates in the power system frequency response.

[0132] At t=0.5s, the system was subjected to a 0.2pu power disturbance, and the frequency exceeded the limit. The hydropower units and the temperature control load cluster responded to the system frequency change and provided power support for system frequency recovery.

[0133] According to the frequency stability, the relationship between the maximum time delay of the temperature control load demand response and the maximum virtual inertia control parameters and the droop control parameters is obtained as follows: Figure 4 When the virtual inertia control parameter is small, the system stability is not affected by the demand response delay. Figure 4 (b) It can be seen that the maximum virtual inertia control parameter that is not affected by the delay after the amplitude-frequency characteristic adjustment is 4.18. The verification results of the virtual inertia control parameter of the temperature control load are as follows: Figure 5 As shown in (a), take K vi =4, even if the delay Δt d =1.5s, the system frequency remains stable. K vi = The maximum delay of demand response calculated theoretically at 7 hours From the verification results, it can be seen that when the response delay is less than the set value The system frequency is stable, otherwise, the system phase margin is negative and the frequency oscillation is unstable.

[0134] Depend on Figure 4 (c) It can be seen that the maximum droop control parameter not affected by the delay is 5.24, K dr =15 Theoretically calculated maximum demand response delay The verification results of the virtual inertia control parameters of the temperature control load are as follows: Figure 5 As shown in (b), the same conclusion can be drawn from the simulation results: when the response delay is less than the set value The system frequency is stable, otherwise, the system phase margin is negative and the frequency oscillation is unstable.

[0135] Therefore, when selecting the virtual inertia control parameters and droop control parameters of the temperature-controlled load frequency response, the parameter design range adjusted in this paper has great reference significance.

[0136] When the frequency response delay of the temperature-controlled load based on the time trigger mechanism is 1s, the value range constraints of the virtual inertia control parameter and the droop control parameter are: K vi ≤4.18, K dr≤18.94. The temperature control load demand response adopts comprehensive inertia control. The above parameter value range will cause system instability. Therefore, the droop control parameter range is adjusted again based on the frequency stability constraint. The droop control parameter K can be obtained by traversal method. dr ≤15.10.

[0137] Furthermore, considering the regulation capacity constraint of the temperature control load, the comprehensive inertia parameters of the temperature control load are optimized.

[0138] Scenario A: All loads are in full load working state, and the maximum adjustment capacity of the temperature control load is 0.2pu.

[0139] Lowering the droop control parameter to 10.98 can satisfy the temperature control load capacity constraint.

[0140] Scenario B: Some loads are off or operating at less than full load. The maximum regulation capacity of the temperature-controlled load cluster is 0.1 pu.

[0141] Lowering the droop control parameter to 3.47 can satisfy the temperature control load capacity constraint.

[0142] Scenario C: During a certain period, the demand for temperature control load is low, and the maximum adjustment capacity of the temperature control load cluster is only 0.05pu.

[0143] Lowering the droop control parameter to 0 still cannot meet the temperature control load capacity constraint. Start to lower the virtual inertia control parameter, K vi The capacity constraint is met when ≤3.02.

[0144] Figure 6-7 is the system frequency response result with the load regulation capacity constraint. From the simulation results of 6(a), we can see that under the comprehensive inertia control parameters adjusted based on the dual constraints of frequency stability and regulation capacity, the load frequency response power will be more in line with engineering and practical needs while satisfying the comprehensive inertia control law. In addition, Figure 6 (b) and Figure 7 It can be seen that the temperature control load can provide more regulation capacity, the frequency regulation pressure of the synchronous power supply will be further reduced, and the dynamic improvement effect on the grid frequency will be better.

[0145] The above-described embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present application, and should all be included in the scope of protection of the present application.

Claims

1. A method for designing integrated inertial control parameters for temperature-controlled load frequency response, comprising the following steps: (1) Establishing a power system frequency response (SFR) control model: a. The conventional units in the power system adopt hydropower units. The transfer function of hydropower units participating in frequency regulation is: The coefficients a0~a3, b0~b4 in the formula are determined by the equivalent parameters of the single unit of the power system, the turbine and the speed control system parameters; b. The temperature control load frequency response is integrated into the power system frequency response model using comprehensive inertia control: Where K vi , K dr , Δt d They are the temperature control load frequency response virtual inertia control parameters, droop control parameters and response delay; (2) Parameter design based on power system frequency stability constraints; a. Design of virtual inertia control parameters; b. Design of droop control parameters; c. Comprehensive inertia control parameter design; c1. The integrated inertia control of the temperature-controlled load prioritizes meeting the system inertia requirements. Based on system stability considerations, the virtual inertia control parameter range in a remains unchanged, and the frequency stability constraint is met by adjusting the droop control parameters in b. c2. Determine the droop control parameters using the ergodic method; adjust the droop control parameters downward according to the reference range in b; (3) Parameter design under the constraints of superimposed load regulation capacity; a. Total regulating capacity of temperature control load ΔP IAC Always meet the power system power regulation instruction requirements, The comprehensive inertia control parameters are always limited to the system frequency stability constraint range; b. The total regulation capacity of the cluster is less than the power regulation instruction requirement of the power system, Adjust the load side comprehensive inertia control parameters; b1. Prioritize adjusting the temperature control load droop control parameter adjustment range to meet the load cluster regulation capacity constraint; b2. Adjust the load droop control parameter to the boundary of 0. If the load cluster regulation capacity constraint still cannot be met, adjust the virtual inertia control parameter.

2. The method for designing comprehensive inertia control parameters for temperature-controlled load frequency response according to claim 1, characterized in that: A power system frequency response model integrating temperature-controlled loads is established. The temperature-controlled loads are integrated into the model using PD control as a fast frequency response resource. The comprehensive inertia control parameters of the temperature control load are designed using the dual constraints of system stability and load frequency regulation capacity; The comprehensive inertia control parameter design analyzes the virtual inertia control link and the droop control link respectively, giving priority to the load's support for the system's virtual inertia; The temperature-controlled load frequency response integrated inertia control parameter design method provides a complete application solution for droop control parameters and virtual inertia control parameters.

3. A method for designing virtual inertia and droop control parameters for temperature-controlled loads based on frequency stability includes the following steps: (1) Obtain the frequency domain amplitude and phase characteristics of the system under virtual inertia control; a. Establish the system open-loop transfer function of the temperature control load frequency response virtual inertia control link: b. Obtain the system amplitude-frequency characteristic A(ω) and phase-frequency characteristic (2) Obtain the expression of the system phase margin γ and the system cutoff frequency ω respectively c , virtual inertia control parameter K vi , load frequency response delay Δt d Correlation with the parameter change of phase margin γ; (3) Adjust the virtual inertia control parameters and load response delay according to the system amplitude and phase stability margin; a. Based on the parameter correlation in (2), the virtual inertia control parameter K vi When the load frequency response delay is small, the system phase margin will not be affected by the load frequency response delay. The maximum inertia control parameter that is not affected by the phase margin is solved. Where, b. Based on the parameter correlation in (2), the virtual inertia control parameter K vi As the phase angle increases gradually, the system phase margin will be affected by the delay, and there will be a response delay Δt that stabilizes the system frequency. d The range of values ​​is: The maximum delay of the temperature control load response subject to phase stability constraints is: c. According to the parameter correlation in (2), the virtual inertia control parameter Response delay Let the amplitude-frequency characteristic A(ω) = 1 to solve the maximum virtual inertia control parameter of the temperature control load corresponding to the current delay: d. According to the parameter correlation in (2), the response delay Δt d is close to 0, and the virtual inertia control parameter constrained by the stability margin condition of the system amplitude-frequency characteristic is: (4) Obtain the frequency domain amplitude and phase characteristics of the system under droop control; a. Establish the system open-loop transfer function of the temperature control load frequency response to the droop control link: b. Obtain the system amplitude-frequency characteristic A(ω) and phase-frequency characteristic (5) Obtain the expression of the system phase margin γ and the system cutoff frequency ω respectively c , droop control parameter K dr , load frequency response delay Δt d Correlation with the parameter change of phase margin γ; (6) Adjust the droop control parameters and load response delay according to the system amplitude and phase stability margin; a. Based on the parameter correlation in (5), the maximum value of the temperature-controlled load droop control parameter when the phase margin is not affected by the delay is: Where, b. According to the parameter correlation in (5), the droop control parameters The maximum delay of the temperature-controlled load response subject to phase stability constraints is solved as follows: c. According to the parameter correlation in (5), response delay Let the amplitude-frequency characteristic A(ω) = 1 to solve the maximum droop control parameter of the temperature control load corresponding to the current delay: d. According to the parameter correlation in (5), the response delay Δt d Close to 0, the temperature control load droop control parameters are not constrained.

4. The method for designing virtual inertia and droop control parameters for temperature-controlled loads based on frequency stability according to claim 3, characterized in that: The virtual inertia control parameters and droop control parameters are designed according to the system amplitude and phase stability margins. According to the system phase angle stability margin, the reference range of load frequency response delay is obtained; According to the amplitude and phase characteristics of the system, the functional relationship between the virtual inertia control parameters and the droop control parameters and the response delay coupling was obtained, which provides comprehensive guidance for the selection of frequency response control parameters for temperature-controlled loads.

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