Micro-grid group operation mode seamless switching control method based on hybrid active disturbance rejection

Abstract

The invention provides a hybrid active disturbance rejection-based microgrid group operation mode seamless switching control method, which comprises the following steps of: firstly, introducing a differential component of an output frequency / voltage of a non-contained distributed power supply and synchronously tracking the differential component of the frequency / voltage of the contained distributed power supply of a microgrid group layer; calculating a non-contained distributed power supply frequency / voltage anti-interference secondary control compensation amount of the micro-grid layer, and designing each contained distributed power supply frequency / voltage anti-interference recovery controller of the micro-grid group layer so as to ensure that each region reliably and stably operates in a new operation mode; and then, through active / reactive power control of a micro-grid layer and a micro-grid group layer, a pre-synchronization controller is additionally designed in combination with hybrid active disturbance rejection, so that voltages and phase angles on the two sides before an interconnection switch is closed are matched, and the hybrid active disturbance rejection is introduced into each control level of the micro-grid group by the method; frequency / voltage autonomous control and pre-synchronization compensation are realized based on system disturbance estimation compensation so as to cope with seamless transition among multiple types of operation modes.

Description

Technical Field

[0001] The present invention relates to the technical field of microgrid group operation control, and in particular to a microgrid group operation mode seamless switching control method based on hybrid auto-disturbance rejection. Background Art

[0002] With the increasing proportion of distributed power sources and new loads, the complexity and coupling of network structure have greatly increased. Microgrid groups will inevitably suffer from abnormal disturbances and sudden faults during operation. If timely and reliable control measures are not taken, disturbances or faults may spread faster, leading to regional cascading faults and even the system entering a completely black state. According to the load operation, operating the section switch / circuit breaker to adjust the network topology is an effective means for microgrid groups to resist abnormal and fault conditions, and how to ensure smooth switching between operating modes is the key to the smooth transition of the system. Most of the existing microgrid group operating mode switching methods consider planned specific scenarios with a certain response margin, but ignore the rapid and real-time action requirements of switches under fault conditions, making it difficult to alleviate the power fluctuations caused by the switching moment and the transient shocks caused by the sudden change of the control signal state quantity. In addition, microgrid groups are nonlinear systems with large dimensions, high orders, multiple disturbances and uncertainties. It is difficult to establish a system response analysis model that takes into account the mapping relationship of switch states, resulting in limited accuracy in suppressing switching disturbances.

[0003] Active disturbance rejection control is an advanced control method without model and parameter dependence, which aims to improve the dynamic response performance of traditional PID controllers, which is difficult to meet the operating requirements of nonlinear, multivariable, and strongly coupled systems. Its core idea is to actively extract disturbance information from the input / output signal of the controlled object before the disturbance has an adverse effect on the system output, and then use the control signal feedforward real-time compensation to eliminate the disturbance as soon as possible, thereby minimizing its impact on the controlled quantity. Active disturbance rejection control can improve the system's active anti-disturbance capability and the accuracy of synchronously tracking the system frequency / voltage reference value, and has a better response speed to internal and external disturbances and shocks caused by changes in the system's operating mode. Summary of the invention

[0004] In view of the deficiencies and gaps in the prior art, the present invention provides a seamless switching control method for a microgrid group operating mode based on hybrid active disturbance rejection to solve the problems existing in the above-mentioned background technology.

[0005] To achieve the above objectives, the present invention is implemented through the following technical solutions:

[0006] On the one hand, a seamless switching control method for a microgrid group operation mode based on hybrid active disturbance rejection is provided, comprising:

[0007] Step A: Collect the state information of each microgrid, introduce the differential component of the output frequency / voltage of the non-constrained distributed power source to synchronize and track the differential component of the frequency / voltage of the microgrid group-level controlled distributed power source, and calculate the secondary control compensation of the frequency / voltage anti-disturbance of the non-constrained distributed power source at the microgrid level;

[0008] Step B: For each distributed power source at the microgrid group level, a frequency / voltage anti-disturbance recovery controller is designed to achieve fast synchronous tracking of the frequency / voltage of the microgrid group to the rated reference value of the system, so as to ensure reliable and stable operation of each area under the new operation mode;

[0009] Step C: Combine the active / reactive power control at the microgrid layer and the microgrid group layer to optimize the power distribution of the interconnected microgrid group so that all distributed power sources in the microgrid group can achieve uniform output of active and reactive power according to their capacity;

[0010] Step D: Based on the above control, a pre-synchronization controller is further designed using hybrid active disturbance rejection to match the voltage and phase angle on both sides before the interconnection switch is closed, further reducing transient fluctuations when the system mode switches to combined operation.

[0011] Furthermore, in step A, calculating the compensation amount required for frequency / voltage regulation in each microgrid includes steps A01 to A03:

[0012] Step A01: Introduce the differential component of the distributed power output frequency / voltage to improve the response speed to system disturbances. Construct the non-constrained distributed power frequency anti-disturbance secondary controller of the microgrid layer according to the following formula:

[0013]

[0014] In the formula, Unconstrained Distributed Generation The hybrid auto-disturbance rejection output frequency adjustment amount, for Linear self-disturbance rejection output frequency adjustment, for Nonlinear self-disturbance rejection output frequency adjustment; for The weight coefficient of frequency regulation; for Positive gain for frequency regulation; for The frequency constant term gain of the linear feedback controller; for The frequency derivative gain of the linear feedback controller; for The frequency constant term gain of the nonlinear feedback controller; for Frequency derivative gain of nonlinear feedback controller; for The frequency-regulated linear observer estimates the total disturbance; for The nonlinear observer of frequency regulation estimates the total disturbance; fhan is a nonlinear function; for The output frequency of k,pin To control the output frequency of distributed power sources; is estimated by the linear observer Frequency derivative; is estimated by the nonlinear observer Frequency derivative; To correspond to the frequency differential component of the distributed power source; for Nonlinear factor of the nonlinear function of the frequency constant term; for Linear interval of nonlinear function of frequency constant term; for Nonlinear factor of the nonlinear function of the frequency differential term; for Linear interval of nonlinear function of frequency differential term; for and The weight between for Get the weight of the frequency reference information.

[0015] Step A02: For The average voltage observer is composed of its local output voltage and the hybrid auto-disturbance rejection output. The specific form is as follows:

[0016]

[0017] In the formula, Unconstrained Distributed Generation Output voltage for The weighted average voltage of for Weight coefficient for average voltage estimation; for Positive gain for average voltage estimation; for Average voltage constant term gain of linear feedback controller; for Average voltage derivative gain of the linear feedback controller; for Average voltage constant term gain of nonlinear feedback controller; for Average voltage derivative gain of the nonlinear feedback controller; for The linear observer of the average voltage estimate estimates the total disturbance; for The nonlinear observer for the average voltage estimate estimates the total disturbance; is estimated by the linear observer Average voltage differential; is estimated by the nonlinear observer Average voltage differential; for Nonlinear factor of the nonlinear function of the average voltage constant term; for The linear interval of the nonlinear function of the average voltage constant term; for Nonlinear factor of the nonlinear function of the average voltage differential term; for The linear interval of the nonlinear function of the average voltage differential term.

[0018] Step A03: Based on the average voltage observer designed by the hybrid anti-disturbance output, the voltage anti-disturbance secondary controller of the microgrid layer is constructed as follows:

[0019]

[0020] In the formula, Unconstrained Distributed Generation The hybrid auto-disturbance rejection output voltage regulation, for Linear self-disturbance rejection output voltage regulation, for Nonlinear self-disturbance rejection output voltage regulation; for Weight coefficient for voltage regulation; for Positive gain for voltage regulation; for The voltage constant term gain of the linear feedback controller; for The voltage derivative gain of the linear feedback controller; for The voltage constant term gain of the nonlinear feedback controller; for The voltage derivative gain of the nonlinear feedback controller; for Linear observer for voltage regulation estimates total disturbance; for Nonlinear observer for voltage regulation estimates total disturbance; is the weighted average voltage corresponding to the distributed generation; To correspond to the average voltage differential of the distributed power source; for Nonlinear factor of the nonlinear function of the voltage constant term; for The linear interval of the nonlinear function of the voltage constant term; for Nonlinear factor of the nonlinear function of the voltage differential term; for Linear interval of nonlinear function of voltage differential term; for Gets the weight of the voltage reference information.

[0021] Furthermore, in step B, a frequency / voltage disturbance rejection and restoration controller at the microgrid group level is designed according to the following steps B01 to B03 to achieve fast synchronous tracking of the frequency / voltage of the microgrid group to the system rated reference value:

[0022] Step B01: Since the system frequency / voltage reference value is a constant, the corresponding tracking differential reference value in the hybrid active disturbance rejection control is 0, and the frequency disturbance rejection recovery controller at the microgrid group level is designed as follows:

[0023]

[0024] In the formula, Ω Hωk,pin For MG k The hybrid anti-disturbance output frequency adjustment value of the distributed power supply is controlled in the middle, Ω Lωk,pin The linear self-disturbance rejection output frequency adjustment corresponding to the distributed power supply is Ω Nωk,pin The corresponding nonlinear self-disturbance rejection output frequency adjustment value of the distributed power supply; ε ωk,pin b is the weight coefficient for controlling the frequency regulation of distributed power sources; ωk,pin To control the positive gain of the distributed power frequency regulation; k L1ωk,pin k is the frequency constant gain of the linear feedback controller for controlling distributed power supply; L2ωk,pin To control the frequency differential gain of the distributed power linear feedback controller; k N1ωk,pin k is the frequency constant gain of the nonlinear feedback controller for controlling distributed power generation; N2ωk,pin To control the frequency differential gain of the distributed power nonlinear feedback controller; L3ωk,pin Estimation of total disturbance for linear observer to control frequency regulation of distributed generation; N3ωk,pin To estimate the total disturbance of the nonlinear observer for the frequency regulation of distributed generation; ω *is the system rated frequency; The frequency derivative of the pinned distributed generation estimated by the linear observer; is the frequency differential component of the distributed generation estimated by the nonlinear observer; ρ′ N1ωk,pin The nonlinear factor that controls the nonlinear function of the frequency constant term of the distributed power supply; δ′ N1ωk,pin is the linear interval of the nonlinear function of the frequency constant term of the distributed power supply; ρ′ N2ωk,pin The nonlinear factor that controls the nonlinear function of the frequency differential term of the distributed power supply; δ′ N2ωk,pin The linear interval for controlling the nonlinear function of the frequency differential term of the distributed power supply; a kl For MG k Central control of distributed power generation and MG l The weight between distributed generation in the middle; g ωk,pin The weight of obtaining rated frequency information for controlling distributed generation.

[0025] Step B02: Based on the hybrid ADRC, an average voltage observer is constructed for each distributed power source in the upper network as shown below:

[0026]

[0027] In the formula, u k,pin For MG k Control the output voltage of distributed power supply; is the weighted average voltage corresponding to the distributed generation; The weight coefficient for estimating the average voltage of distributed generation; To contain the positive gain of the average voltage estimate of the distributed generation; To control the average voltage constant gain of the distributed power linear feedback controller; To control the average voltage differential gain of the distributed power linear feedback controller; To control the average voltage constant gain of the distributed power nonlinear feedback controller; To control the average voltage differential gain of the distributed power nonlinear feedback controller; Estimation of total disturbance for linear observer to pin down average voltage estimation of distributed generation; Estimation of total disturbance for nonlinear observer to pin down average voltage estimation of distributed generation; The average voltage derivative of the distributed generation estimated by the linear observer; The average voltage derivative of the pinned distributed generation estimated by the nonlinear observer; The nonlinear factor for restraining the nonlinear function of the average voltage constant term of the distributed generation; To control the linear interval of the nonlinear function of the average voltage constant term of the distributed generation; The nonlinear factor to control the nonlinear function of the average voltage differential term of the distributed generation; It is the linear interval to control the nonlinear function of the differential term of the average voltage of distributed generation.

[0028] Step B03: Based on the average voltage observer, an average voltage recovery controller for each distributed power source at the microgrid group level is constructed as follows:

[0029]

[0030] In the formula, Φ Huk,pin For MG k The hybrid auto-disturbance rejection output voltage regulation of the distributed power supply is controlled by Φ Luk,pin To correspond to the linear self-disturbance rejection output voltage regulation of the distributed power supply, Φ Nuk,pin The corresponding nonlinear self-disturbance rejection output voltage regulation value of the distributed power supply; ε uk,pin b is the weight coefficient for controlling the voltage regulation of distributed power supply; uk,pin To control the positive gain of the distributed power supply voltage regulation; k L1uk,pin k is the voltage constant gain of the distributed power linear feedback controller; L2uk,pin To control the voltage differential gain of the distributed power linear feedback controller; k N1uk,pin k is the voltage constant gain of the distributed power nonlinear feedback controller; N2uk,pin To control the voltage differential gain of the distributed power nonlinear feedback controller; L3uk,pin Estimation of total disturbance for linear observer to control distributed generation voltage regulation; N3uk,pin Estimation of total disturbance for nonlinear observer to control distributed generation voltage regulation; is the system rated voltage; The average voltage derivative of the distributed generation estimated by the linear observer; is the average voltage differential of the distributed generation estimated by the nonlinear observer; ρ′ N1uk,pin The nonlinear factor to control the nonlinear function of the voltage constant term of the distributed power supply; δ′ N1uk,pin is the linear interval of the nonlinear function of the voltage constant term of the distributed power supply; ρ′ N2uk,pin The nonlinear factor to control the nonlinear function of the differential term of the distributed power supply voltage; δ′ N2uk,pin g is the linear interval for controlling the nonlinear function of the differential term of the distributed power supply voltage; uk,pin The weight of obtaining rated voltage information for controlling distributed generation.

[0031] Furthermore, in step C, the active / reactive power control at the microgrid layer and the microgrid group layer is combined according to the following steps, so that all distributed power sources in the microgrid group can achieve uniform output of active and reactive power according to their capacities:

[0032] Step C01: Considering that the active and reactive power output by the controlled distributed power sources in the microgrid are affected by the upper network information interaction, there is no need to obtain power state quantity information from the non-controlled distributed power sources. The power sharing controller in the microgrid is constructed as follows:

[0033]

[0034] In the formula, Unconstrained Distributed Generation Active power regulation; Unconstrained Distributed Generation Reactive power regulation; and They are Positive control gain for active and reactive power regulation; and They are Active and reactive power droop coefficients; and They are Output active and reactive power; m k,pin and n k,pin MG k The active and reactive power droop coefficients of distributed generation are controlled; P k,pin , and Q k,pin They are used to control the output active and reactive power of distributed power sources respectively; is the lower layer network G k The sth triggering moment, is the sth triggering moment of the upper network; and They are Get the weights of active and reactive power reference information.

[0035] Step C02: Considering that the droop coefficient of the distributed power source is inversely proportional to the starting capacity, each controlled distributed power source can exchange the capacity information of its corresponding microgrid through the upper network, and then continuously iterate and correct the output deviation of each controlled distributed power source to achieve uniform output among microgrids according to the capacity size. The power sharing controller at the microgrid group layer is designed as follows:

[0036]

[0037] In the formula, Ω Pk,pin For MG kThe active power regulation amount of the distributed power source is controlled; Φ Qk,pin For MG k The reactive power regulation of distributed power generation is controlled in the middle; k Pk,pin and k Qk,pin They are the positive control gains for controlling the active and reactive power regulation of distributed generation respectively.

[0038] Furthermore, in step D, a presynchronization controller is additionally designed using hybrid active disturbance rejection in the following steps, so that the voltages and phase angles on both sides are matched before the interconnection switch is closed, and the transient fluctuations when the system mode is switched to the combined operation are further reduced:

[0039] Step D01: The difference between the dq axis components of the voltages on both sides of the interconnected switch represents the amplitude difference and phase angle difference. Then for the i-th distributed generation DG k,i , the presynchronization controller can be expressed as:

[0040]

[0041] In the formula, Ω sk,i To superimpose on DG k,i The adjustment amount of the active power-frequency droop equation; Φ sk,i To superimpose on DG k,i The regulation quantity of reactive power-power droop equation; ξ k is the pre-synchronization start coefficient, if ξ k =1, indicating that the voltage / phase angle synchronization control is started on both sides of the interconnection, otherwise it is 0; and Respectively represent the voltage phase angle difference and amplitude difference on both sides of the switch to be closed; Ω Lsk,i is the phase angle adjustment value generated by the corresponding linear auto-disturbance rejection; Ω Nsk,i is the phase angle adjustment value generated by the nonlinear self-disturbance rejection; Φ Lsk,i is the amplitude adjustment value generated by the corresponding linear auto-disturbance rejection; Φ Nsk,i is the amplitude adjustment value generated by the corresponding nonlinear self-disturbance rejection; ε sqk,i and ε sdk,i are the weight coefficients for phase angle and amplitude adjustment respectively; b sqk,i and b sdk,i are the positive gains for phase angle and amplitude adjustment respectively; k L1sqk,i is the phase angle constant gain of the linear feedback controller; k L2sqk,i is the phase angle differential gain of the linear feedback controller; k N1sqk,i is the phase angle constant gain of the nonlinear feedback controller; k N2sqk,i is the phase differential gain of the nonlinear feedback controller; k L1sdk,i is the amplitude constant gain of the linear feedback controller; k L2sdk,iis the amplitude differential gain of the linear feedback controller; k N1sdk,i is the amplitude constant gain of the nonlinear feedback controller; k N2sdk,i is the amplitude differential gain of the nonlinear feedback controller; ρ′ N1sqk,i is the nonlinear factor of the nonlinear function of the phase angle constant term; δ′ N1sqk,i is the linear interval of the nonlinear function of the phase angle constant term; ρ′ N2sqk,i is the nonlinear factor of the nonlinear function of the phase angle differential term; δ′ N2sqk,i is the linear interval of the nonlinear function of the phase angle differential term; ρ′ N1sdk,i is the nonlinear factor of the nonlinear function of the amplitude constant term; δ′ N1sdk,i is the linear interval of the nonlinear function of the amplitude constant term; ρ′ N2sdk,i is the nonlinear factor of the nonlinear function of the amplitude differential term; δ′ N2sdk,i is the linear interval of the nonlinear function of the amplitude differential term; z L3sqk,i Estimate the total disturbance for the phase-adjusted linear observer; z N3sqk,i Estimate the total disturbance for the phase-angle-adjusted nonlinear observer; z L3sdk,i is the linear estimated total disturbance adjusted by amplitude; z N3sdk,i Estimating the total disturbance for an amplitude-adjusted nonlinear observer.

[0042] Step D02: Before the system performs the microgrid merging and interconnection operation, set ψ k is the interconnection switch symbol between different microgrids, ψ k =1 means the voltage and phase angle on both sides of the switch are inconsistent, and the switch is disconnected; ψ k =0 means that the voltage and phase angle on both sides of the switch are consistent and the switch is closed.

[0043] An electronic device comprises a memory, a processor and a computer program stored in the memory and executable on the processor. When the processor executes the program, a seamless switching control method for operating modes of a microgrid group based on hybrid self-disturbance rejection is implemented.

[0044] A computer-readable storage medium stores computer instructions, which, when executed by a processor, implement a seamless switching control method for operating modes of a microgrid group based on hybrid auto-disturbance rejection.

[0045] The present invention designs a seamless switching control method for the operation mode of a microgrid group based on hybrid auto-disturbance rejection, introduces hybrid auto-disturbance rejection into each control level of the microgrid group, and designs frequency / voltage autonomous controllers and pre-synchronization compensation controllers based on system disturbance prediction compensation to cope with seamless transitions between multiple types of operation scenarios. The differential components of the output frequency / voltage of the non-constrained distributed power source are introduced to synchronize and track the differential components of the frequency / voltage of the microgrid group-level constrained distributed power source to improve the response speed to system disturbances. During the operation mode switching process, the frequency / voltage regulator adaptively adjusts the auto-disturbance rejection coefficient according to the absolute value of the error and the size of the total disturbance to improve the anti-disturbance capability, and accurately tracks the target value of the distributed power source. Through the active / reactive power control of the microgrid layer and the microgrid group layer, the power distribution of the interconnected microgrid group is optimized, so that all distributed power sources evenly distribute active and reactive power according to their capacity. The present invention also uses hybrid auto-disturbance rejection to additionally design a pre-synchronization controller so that the voltage and phase angle on both sides before the interconnection switch is closed match, further reducing the transient fluctuation when the system mode is switched to the combined operation. The present invention provides a new idea for seamless switching of operating modes of a microgrid group. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 is a flow chart of the control method of the present invention;

[0047] Figure 2 It is a microgrid group simulation test system used in an embodiment of the present invention;

[0048] Figure 3 : is a frequency waveform diagram of each microgrid in an embodiment of the present invention;

[0049] Figure 4 : is a bus voltage waveform diagram of each microgrid in an embodiment of the present invention;

[0050] Figure 5 is a waveform diagram of active power output by each distributed power source in a microgrid group in an embodiment of the present invention;

[0051] Figure 6 It is a waveform diagram of reactive power output by each distributed power source in the microgrid group in an embodiment of the present invention. DETAILED DESCRIPTION

[0052] The following will be combined with the accompanying drawings of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0053] Example: Figure 1As shown, the present invention designs a seamless switching control method for microgrid group operation modes based on hybrid active disturbance rejection. In practical application, the method specifically includes the following steps:

[0054] Step A: Collect the state information of each microgrid, introduce the differential component of the output frequency / voltage of the non-constrained distributed power source to synchronize and track the differential component of the frequency / voltage of the microgrid group-level controlled distributed power source, calculate the secondary control compensation amount of the frequency / voltage anti-disturbance of the non-constrained distributed power source at the microgrid layer, and then enter step B;

[0055] Step B: For each distributed power source at the microgrid group layer, design a frequency / voltage anti-disturbance recovery controller at the microgrid group layer to achieve fast synchronous tracking of the frequency / voltage of the microgrid group to the rated reference value of the system, so as to ensure that each area operates reliably and stably under the new operation mode, and then proceed to step C;

[0056] Step C: Combine the active / reactive power control at the microgrid layer and the microgrid group layer to optimize the power distribution of the interconnected microgrid group so that all distributed power sources in the microgrid group can achieve uniform output of active and reactive power according to their capacity, and then proceed to step D;

[0057] Step D: Based on the above control, a pre-synchronization controller is further designed using hybrid active disturbance rejection to match the voltage and phase angle on both sides before the interconnection switch is closed, further reducing transient fluctuations when the system mode switches to combined operation.

[0058] In the above step A, the compensation amount required for frequency / voltage regulation in each microgrid is calculated by the following steps A01 to A03:

[0059] Step A01: Introduce the differential component of the distributed power output frequency / voltage to improve the response speed to system disturbances. Construct the non-constrained distributed power frequency anti-disturbance secondary controller of the microgrid layer according to the following formula:

[0060]

[0061] In the formula, Unconstrained Distributed Generation The hybrid auto-disturbance rejection output frequency adjustment amount, for Linear self-disturbance rejection output frequency adjustment, for Nonlinear self-disturbance rejection output frequency adjustment; for The weight coefficient of frequency regulation; for Positive gain for frequency regulation; for The frequency constant term gain of the linear feedback controller; for The frequency derivative gain of the linear feedback controller; for The frequency constant term gain of the nonlinear feedback controller; for Frequency derivative gain of nonlinear feedback controller; for The frequency-regulated linear observer estimates the total disturbance; for The nonlinear observer of frequency regulation estimates the total disturbance; fhan is a nonlinear function; for The output frequency of k,pin To control the output frequency of distributed power sources; is estimated by the linear observer Frequency derivative; is estimated by the nonlinear observer Frequency derivative; To correspond to the frequency differential component of the distributed power source; for Nonlinear factor of the nonlinear function of the frequency constant term; for Linear interval of nonlinear function of frequency constant term; for Nonlinear factor of the nonlinear function of the frequency differential term; for Linear interval of nonlinear function of frequency differential term; for and The weight between for Get the weight of the frequency reference information.

[0062] Step A02: For The average voltage observer is composed of its local output voltage and the hybrid auto-disturbance rejection output. The specific form is as follows:

[0063]

[0064] In the formula, Unconstrained Distributed Generation Output voltage for The weighted average voltage of for Weight coefficient for average voltage estimation; for Positive gain for average voltage estimation; for Average voltage constant term gain of linear feedback controller; for Average voltage derivative gain of the linear feedback controller; for Average voltage constant term gain of nonlinear feedback controller; for Average voltage derivative gain of the nonlinear feedback controller; for The linear observer of the average voltage estimate estimates the total disturbance; for The nonlinear observer for the average voltage estimate estimates the total disturbance; is estimated by the linear observer Average voltage differential; is estimated by the nonlinear observer Average voltage differential; for Nonlinear factor of the nonlinear function of the average voltage constant term; for The linear interval of the nonlinear function of the average voltage constant term; for Nonlinear factor of the nonlinear function of the average voltage differential term; for The linear interval of the nonlinear function of the average voltage differential term.

[0065] Step A03: Based on the average voltage observer designed by the hybrid anti-disturbance output, the voltage anti-disturbance secondary controller of the microgrid layer is constructed as follows:

[0066]

[0067] In the formula, Unconstrained Distributed Generation The hybrid auto-disturbance rejection output voltage regulation, for Linear self-disturbance rejection output voltage regulation, for Nonlinear self-disturbance rejection output voltage regulation; for Weight coefficient for voltage regulation; for Positive gain for voltage regulation; for The voltage constant term gain of the linear feedback controller; for The voltage derivative gain of the linear feedback controller; for The voltage constant term gain of the nonlinear feedback controller; for The voltage derivative gain of the nonlinear feedback controller; for Linear observer for voltage regulation estimates total disturbance; for Nonlinear observer for voltage regulation estimates total disturbance; is the weighted average voltage corresponding to the distributed generation; To correspond to the average voltage differential of the distributed power source; for Nonlinear factor of the nonlinear function of the voltage constant term; for The linear interval of the nonlinear function of the voltage constant term; for Nonlinear factor of the nonlinear function of the voltage differential term; for Linear interval of nonlinear function of voltage differential term; for Gets the weight of the voltage reference information.

[0068] The frequency / voltage regulator of the microgrid layer adaptively adjusts the weight coefficient of the corresponding hybrid active disturbance rejection control according to the absolute value of the error and the size of the total disturbance during the operation mode switching process. and promote Anti-interference ability, and accurate tracking of the target value of the controlled distributed power generation. In addition, the frequency / voltage regulation generated by equations (1) and (3) does not need to act through the integral link, but is directly superimposed on the active-frequency loop and reactive-voltage loop of the corresponding non-controlled distributed power generation droop control equation.

[0069] In the above step B, the frequency / voltage disturbance rejection and restoration controller of the microgrid group layer is designed from steps B01 to B03 to achieve fast synchronous tracking of the frequency / voltage of the microgrid group to the system rated reference value:

[0070] Step B01: Since the system frequency / voltage reference value is a constant, the corresponding tracking differential reference value in the hybrid active disturbance rejection control is 0, and the frequency disturbance rejection recovery controller at the microgrid group level is designed as follows:

[0071]

[0072] In the formula, Ω Hωk,pin For MG k The hybrid anti-disturbance output frequency adjustment value of the distributed power supply is controlled in the middle, Ω Lωk,pin The linear self-disturbance rejection output frequency adjustment corresponding to the distributed power supply is Ω Nωk,pinThe corresponding nonlinear self-disturbance rejection output frequency adjustment value of the distributed power supply; ε ωk,pin b is the weight coefficient for controlling the frequency regulation of distributed power sources; ωk,pin To control the positive gain of the distributed power frequency regulation; k L1ωk,pin k is the frequency constant gain of the linear feedback controller for controlling distributed power supply; L2ωk,pin To control the frequency differential gain of the distributed power linear feedback controller; k N1ωk,pin k is the frequency constant gain of the nonlinear feedback controller for controlling distributed power generation; N2ωk,pin To control the frequency differential gain of the distributed power nonlinear feedback controller; L3ωk,pin Estimation of total disturbance for linear observer to control frequency regulation of distributed generation; N3ωk,pin To estimate the total disturbance of the nonlinear observer for the frequency regulation of distributed generation; ω * is the system rated frequency; The frequency derivative of the pinned distributed generation estimated by the linear observer; is the frequency differential component of the distributed generation estimated by the nonlinear observer; ρ′ N1ωk,pin The nonlinear factor that controls the nonlinear function of the frequency constant term of the distributed power supply; δ′ N1ωk,pin is the linear interval of the nonlinear function of the frequency constant term of the distributed power supply; ρ′ N2ωk,pin The nonlinear factor that controls the nonlinear function of the frequency differential term of the distributed power supply; δ′ N2ωk,pin The linear interval for controlling the nonlinear function of the frequency differential term of the distributed power supply; a kl For MG k Central control of distributed power generation and MG l The weight between distributed generation in the middle; g ωk,pin The weight of obtaining rated frequency information for controlling distributed generation.

[0073] Step B02: Based on the hybrid ADRC, an average voltage observer is constructed for each distributed power source in the upper network as shown below:

[0074]

[0075] In the formula, u k,pin For MG k Control the output voltage of distributed power supply; is the weighted average voltage corresponding to the distributed generation; The weight coefficient for estimating the average voltage of distributed generation; To contain the positive gain of the average voltage estimate of the distributed generation; To control the average voltage constant gain of the distributed power linear feedback controller; To control the average voltage differential gain of the distributed power linear feedback controller; To control the average voltage constant gain of the distributed power nonlinear feedback controller; To control the average voltage differential gain of the distributed power nonlinear feedback controller; Estimation of total disturbance for linear observer to pin down average voltage estimation of distributed generation; Estimation of total disturbance for nonlinear observer to pin down average voltage estimation of distributed generation; The average voltage derivative of the distributed generation estimated by the linear observer; The average voltage derivative of the pinned distributed generation estimated by the nonlinear observer; The nonlinear factor for restraining the nonlinear function of the average voltage constant term of the distributed generation; To control the linear interval of the nonlinear function of the average voltage constant term of the distributed generation; The nonlinear factor to control the nonlinear function of the average voltage differential term of the distributed generation; It is the linear interval to control the nonlinear function of the differential term of the average voltage of distributed generation.

[0076] Step B03: Based on the average voltage observer, an average voltage recovery controller for each distributed power source at the microgrid group level is constructed as follows:

[0077]

[0078] In the formula, Φ Huk,pin For MG k The hybrid auto-disturbance rejection output voltage regulation of the distributed power supply is controlled by Φ Luk,pin To correspond to the linear self-disturbance rejection output voltage regulation of the distributed power supply, Φ Nuk,pin The corresponding nonlinear self-disturbance rejection output voltage regulation value of the distributed power supply; ε uk,pin b is the weight coefficient for controlling the voltage regulation of distributed power supply; uk,pin To control the positive gain of the distributed power supply voltage regulation; k L1uk,pin k is the voltage constant gain of the distributed power linear feedback controller; L2uk,pin To control the voltage differential gain of the distributed power linear feedback controller; k N1uk,pin k is the voltage constant gain of the distributed power nonlinear feedback controller; N2uk,pin To control the voltage differential gain of the distributed power nonlinear feedback controller; L3uk,pin Estimation of total disturbance for linear observer to control distributed generation voltage regulation; N3uk,pin Estimation of total disturbance for nonlinear observer to control distributed generation voltage regulation; is the system rated voltage; The average voltage derivative of the distributed generation estimated by the linear observer; is the average voltage differential of the distributed generation estimated by the nonlinear observer; ρ′ N1uk,pin The nonlinear factor to control the nonlinear function of the voltage constant term of the distributed power supply; δ′ N1uk,pin is the linear interval of the nonlinear function of the voltage constant term of the distributed power supply; ρ′ N2uk,pin The nonlinear factor to control the nonlinear function of the differential term of the distributed power supply voltage; δ′ N2uk,pin g is the linear interval for controlling the nonlinear function of the differential term of the distributed power supply voltage; uk,pin The weight of obtaining rated voltage information for controlling distributed generation.

[0079] Formula (4) to Formula (6) adaptively adjust the weight coefficient ε according to the estimated frequency / error absolute value and the size of the total disturbance during the system operation mode switching process. ωk,pin and ε uk,pin , improving the active anti-interference capability of each control node and the accuracy of synchronous tracking system frequency / voltage reference value. Similarly, the generated frequency / voltage adjustment value Ω Hωk,pin and Φ Huk,pin They are directly superimposed on the active-frequency loop and reactive-voltage loop corresponding to the droop control of distributed generation.

[0080] In the above step C, steps C01 to C02 are combined with active / reactive power control at the microgrid layer and the microgrid group layer, so that all distributed power sources in the microgrid group can achieve uniform output of active and reactive power according to their capacity:

[0081] Step C01: Considering that the active and reactive power output by the controlled distributed power sources in the microgrid are affected by the upper network information interaction, there is no need to obtain power state quantity information from the non-controlled distributed power sources. The power sharing controller in the microgrid is constructed as follows:

[0082]

[0083] In the formula, Unconstrained Distributed Generation Active power regulation; Unconstrained Distributed Generation Reactive power regulation; and They are Positive control gain for active and reactive power regulation; and They are Active and reactive power droop coefficients; and They are Output active and reactive power; m k,pin and n k,pin MG k The active and reactive power droop coefficients of distributed generation are controlled; P k,pin , and Q k,pin They are used to control the output active and reactive power of distributed power sources respectively; is the lower layer network G k The sth triggering moment, is the sth triggering moment of the upper network; and They are Get the weights of active and reactive power reference information.

[0084] Once in formula (7) and formula (8) as well as MG k All distributed power sources within the system can achieve uniform output of active and reactive power according to their capacity.

[0085] Step C02: Considering that the droop coefficient of the distributed power source is inversely proportional to the starting capacity, each controlled distributed power source can exchange the capacity information of its corresponding microgrid through the upper network, and then continuously iterate and correct the output deviation of each controlled distributed power source to achieve uniform output among microgrids according to the capacity size. The power sharing controller at the microgrid group layer is designed as follows:

[0086]

[0087] In the formula, Ω Pk,pin For MG k The active power regulation amount of the distributed power source is controlled; Φ Qk,pin For MG k The reactive power regulation of distributed power generation is controlled in the middle; k Pk,pin and k Qk,pin They are the positive control gains for controlling the active and reactive power regulation of distributed generation respectively.

[0088] Once m k,pin P k,pin →m l,pin P l,pin and n k,pin Q k,pin →n l,pin Q l,pin , the global distributed power generation power can be evenly distributed according to capacity through tracking and synchronization of the lower-level network.

[0089] In the above step D, the pre-synchronization controller is additionally designed by using hybrid active disturbance rejection in the following steps D01 to D02, so that the voltage and phase angle on both sides are matched before the interconnection switch is closed, and the transient fluctuation when the system mode is switched to the combined operation is further reduced:

[0090] Step D01: The difference between the dq axis components of the voltages on both sides of the interconnected switch represents the amplitude difference and phase angle difference. Then for the i-th distributed generation DG k,i , the presynchronization controller can be expressed as:

[0091]

[0092]

[0093] In the formula, Ω sk,i To superimpose on DG k,i The adjustment amount of the active power-frequency droop equation; Φ sk,i To superimpose on DG k,i The regulation quantity of reactive power-power droop equation; ξ k is the pre-synchronization start coefficient, if ξ k =1, indicating that the voltage / phase angle synchronization control is started on both sides of the interconnection, otherwise it is 0; and Respectively represent the voltage phase angle difference and amplitude difference on both sides of the switch to be closed; Ω Lsk,i is the phase angle adjustment value generated by the corresponding linear auto-disturbance rejection; Ω Nsk,i is the phase angle adjustment value generated by the nonlinear self-disturbance rejection; Φ Lsk,i is the amplitude adjustment value generated by the corresponding linear auto-disturbance rejection; Φ Nsk,i is the amplitude adjustment value generated by the corresponding nonlinear self-disturbance rejection; ε sqk,i and ε sdk,i are the weight coefficients for phase angle and amplitude adjustment respectively; b sqk,i and b sdk,i are the positive gains for phase angle and amplitude adjustment respectively; k L1sqk,i is the phase angle constant gain of the linear feedback controller; k L2sqk,i is the phase angle differential gain of the linear feedback controller; k N1sqk,i is the phase angle constant gain of the nonlinear feedback controller; k N2sqk,i is the phase differential gain of the nonlinear feedback controller; k L1sdk,i is the amplitude constant gain of the linear feedback controller; k L2sdk,i is the amplitude differential gain of the linear feedback controller; k N1sdk,i is the amplitude constant gain of the nonlinear feedback controller; k N2sdk,i is the amplitude differential gain of the nonlinear feedback controller; ρ′ N1sqk,i is the nonlinear factor of the nonlinear function of the phase angle constant term; δ′N1sqk,i is the linear interval of the nonlinear function of the phase angle constant term; ρ′ N2sqk,i is the nonlinear factor of the nonlinear function of the phase angle differential term; δ′ N2sqk,i is the linear interval of the nonlinear function of the phase angle differential term; ρ′ N1sdk,i is the nonlinear factor of the nonlinear function of the amplitude constant term; δ′ N1sdk,i is the linear interval of the nonlinear function of the amplitude constant term; ρ′ N2sdk,i is the nonlinear factor of the nonlinear function of the amplitude differential term; δ′ N2sdk,i is the linear interval of the nonlinear function of the amplitude differential term; z L3sqk,i Estimate the total disturbance for the phase-adjusted linear observer; z N3sqk,i Estimate the total disturbance for the phase-angle-adjusted nonlinear observer; z L3sdk,i is the linear estimated total disturbance adjusted by amplitude; z N3sdk,i Estimating the total disturbance for an amplitude-adjusted nonlinear observer.

[0094] Step D02: Before the system performs the microgrid merging and interconnection operation, set ψ k is the interconnection switch symbol between different microgrids, ψ k =1 means the voltage and phase angle on both sides of the switch are inconsistent, and the switch is disconnected; ψ k =0 means the voltage and phase angle on both sides of the switch are consistent and the switch is closed. At the same time, the frequency / voltage anti-disturbance controllers work together to suppress the disturbance or impact caused by the instantaneous switch closing, and achieve a smooth transition of the operating state.

[0095] Apply the above-mentioned technical solution to practice, the simulation system is as follows Figure 2 As shown in the figure, a microgrid group system is formed by connecting three microgrids (MGs), each of which contains three DGs with the same capacity, which are connected to the voltage bus through different line impedances. 11 , D.G. 21 , D.G. 31 Set as a containment node and form an inter-group communication network. According to the hybrid anti-disturbance control method for seamless switching of microgrid group operation modes in an embodiment of the present invention, a system controller is established, and a microgrid group model is built based on the MATLAB / Simulink simulation platform to verify the control effect of the method of the present invention.

[0096] Corresponds to Figure 2, set the microgrid group operation mode switching simulation conditions. The specific operation conditions are set as follows: 1) At the initial moment, the circuit breakers CB1-CB3 are all closed, the three microgrids form a microgrid group and operate in coordination, and the microgrid group layer and microgrid layer controllers are started; 2) At 4 seconds, the load Load4 is put into the system common bus (simulating the condition of a small disturbance in the system); 3) At 6 seconds, MG1 is unplanned and runs independently (simulating the condition of a large disturbance in the system), and MG2 and MG3 continue to operate in interconnection; 4) At 8 seconds, the fault is eliminated and the merge pre-synchronization of MG1 is started; 5) At 10 seconds, MG1 is re-merged and the three microgrids are restored to operate in coordination. Figures 3 to 6 Corresponding to the simulation results under the operating conditions in this embodiment. Figure 3 It is the frequency waveform diagram of each microgrid. The horizontal axis represents time, unit: second, and the vertical axis represents frequency, unit: Hertz. Figure 4 It is the bus voltage waveform of each microgrid. The horizontal axis represents time, unit: second, and the vertical axis represents voltage, unit: volt. Figure 5 It is the waveform diagram of the active power output of DG in each microgrid. The horizontal axis represents time in seconds, and the vertical axis represents active power in kilowatts. Figure 6 The waveform diagram of reactive power output by DG in each microgrid, the horizontal axis represents time, unit: second, the vertical axis represents active power, unit: kvar. Figures 3 to 6 It can be seen that within 0 to 2 seconds, under the joint action of the frequency / voltage regulator and the active / reactive power controller, the frequency / bus voltage of each microgrid is maintained at the rated value, and all distributed power sources in the group distribute active and reactive power according to capacity; at 4 seconds, under the condition of small disturbance, the frequency / voltage has a very small fluctuation, and the global active and reactive power are still evenly distributed according to capacity; at 6 seconds, under the condition of large disturbance, the frequency / voltage returns to the rated value after a short fluctuation, and the active and reactive power reach a new steady-state convergence value again; at 8 seconds, the merge pre-synchronization of MG1 is started, so that the voltage and phase angle on both sides of the circuit breaker can match; at 10 seconds, MG1 is re-merged, the transient fluctuation of frequency / voltage is small, and under the new operating mode, the global power reaches the equal distribution state again. During the whole simulation process, each microgrid has a small overshoot in the dynamic process, which reflects that the method of the present invention has good anti-interference performance.

[0097] The present invention proposes a control method for seamless switching of microgrid group operation modes based on hybrid auto-disturbance rejection. First, the differential component of the output frequency / voltage of the non-constrained distributed power source at the microgrid layer is introduced to synchronize and track the differential component of the frequency / voltage of the constrained distributed power source at the microgrid group layer, the secondary control compensation of the frequency / voltage anti-disturbance at the microgrid layer is calculated, and the frequency / voltage anti-disturbance recovery controller at the microgrid group layer is designed to ensure that each area operates reliably and stably under the new operation mode; then, through the active / reactive power control at the microgrid layer and the microgrid group layer, all distributed power sources can achieve active and reactive power equalization according to their capacity; secondly, a pre-synchronization controller is additionally designed in combination with hybrid auto-disturbance rejection, so that the voltage and phase angle on both sides are matched before the interconnection switch is closed, and the transient fluctuation when the system mode is switched to the combined operation is further reduced. The method introduces hybrid auto-disturbance rejection into each control level of the microgrid group, and designs the frequency / voltage autonomous controller and the pre-synchronization compensation controller based on the system disturbance prediction compensation to cope with the seamless transition between multiple types of operation modes. The present invention provides a feasible and effective implementation plan for seamless switching of microgrid group operation modes.

[0098] In the description of this specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. 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. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0099] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand 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, and these changes and improvements all fall within the scope of the present invention to be protected.

Claims

1. A seamless switching control method for microgrid group operation modes based on hybrid active disturbance rejection, characterized in that: The method comprises the following steps: Step A: Collect the state information of each microgrid, introduce the differential component of the output frequency / voltage of the non-constrained distributed power source to synchronize and track the differential component of the frequency / voltage of the microgrid group-level controlled distributed power source, and calculate the secondary control compensation of the frequency / voltage anti-disturbance of the non-constrained distributed power source at the microgrid level; Step B: For each distributed power source in the microgrid group layer, a frequency / voltage disturbance recovery controller is designed to achieve fast synchronous tracking of the frequency / voltage of the microgrid group to the rated reference value of the system, so as to ensure reliable and stable operation of each area under the new operation mode; Step C: Combine the active / reactive power control at the microgrid layer and the microgrid group layer to optimize the power distribution of the interconnected microgrid group so that all distributed power sources in the microgrid group can achieve uniform output of active and reactive power according to their capacity; Step D: Based on the above control, a pre-synchronization controller is additionally designed using hybrid active disturbance rejection to match the voltage and phase angle on both sides before the interconnection switch is closed, thereby reducing transient fluctuations when the system mode switches to combined operation.

2. According to claim 1, a microgrid group operating mode seamless switching control method based on hybrid auto-disturbance rejection is characterized in that: In step A, the secondary control compensation amount is calculated through the following steps A01 to A03 to achieve frequency / voltage regulation in each microgrid: Step A01: Introduce the differential component of the distributed power output frequency / voltage, and construct the non-constrained distributed power frequency anti-disturbance secondary controller of the microgrid layer according to the above formula. In the formula, Unconstrained Distributed Generation The hybrid auto-disturbance rejection output frequency adjustment amount, for Linear self-disturbance rejection output frequency adjustment, for Nonlinear self-disturbance rejection output frequency adjustment; for The weight coefficient of frequency regulation; for Positive gain for frequency regulation; for The frequency constant term gain of the linear feedback controller; for The frequency derivative gain of the linear feedback controller; for The frequency constant term gain of the nonlinear feedback controller; for Frequency derivative gain of nonlinear feedback controller; for The frequency-regulated linear observer estimates the total disturbance; for The nonlinear observer of frequency regulation estimates the total disturbance; fhan is a nonlinear function; for The output frequency of k,pin To control the output frequency of distributed power sources; is estimated by the linear observer Frequency derivative; is estimated by the nonlinear observer Frequency derivative; To correspond to the frequency differential component of the distributed power source; for Nonlinear factor of the nonlinear function of the frequency constant term; for Linear interval of nonlinear function of frequency constant term; for Nonlinear factor of the nonlinear function of the frequency differential term; for Linear interval of nonlinear function of frequency differential term; for and The weight between for Get the weight of the frequency reference information, Step A02: The local output voltage is combined with the hybrid auto-disturbance rejection output The average voltage observer is as follows: In the formula, Unconstrained Distributed Generation Output voltage for The weighted average voltage of for Weight coefficient for average voltage estimation; for Positive gain for average voltage estimation; for Average voltage constant term gain of linear feedback controller; for Average voltage derivative gain of the linear feedback controller; for Average voltage constant term gain of nonlinear feedback controller; for Average voltage derivative gain of the nonlinear feedback controller; for The linear observer of the average voltage estimate estimates the total disturbance; for The nonlinear observer for the average voltage estimate estimates the total disturbance; is estimated by the linear observer Average voltage differential; is estimated by the nonlinear observer Average voltage differential; for Nonlinear factor of the nonlinear function of the average voltage constant term; for The linear interval of the nonlinear function of the average voltage constant term; for Nonlinear factor of the nonlinear function of the average voltage differential term; for The linear interval of the nonlinear function of the average voltage differential term, Step A03: Based on the average voltage observer designed by the hybrid anti-disturbance output, the voltage anti-disturbance secondary controller of the microgrid layer is constructed as follows: In the formula, Unconstrained Distributed Generation The hybrid auto-disturbance rejection output voltage regulation, for Linear self-disturbance rejection output voltage regulation, for Nonlinear self-disturbance rejection output voltage regulation; for Weight coefficient for voltage regulation; for Positive gain for voltage regulation; for The voltage constant term gain of the linear feedback controller; for The voltage derivative gain of the linear feedback controller; for The voltage constant term gain of the nonlinear feedback controller; for The voltage derivative gain of the nonlinear feedback controller; for Linear observer for voltage regulation estimates total disturbance; for Nonlinear observer for voltage regulation estimates total disturbance; is the weighted average voltage corresponding to the distributed generation; To correspond to the average voltage differential of the distributed power source; for Nonlinear factor of the nonlinear function of the voltage constant term; for The linear interval of the nonlinear function of the voltage constant term; for Nonlinear factor of the nonlinear function of the voltage differential term; for The linear interval of the nonlinear function of the voltage differential term; for Gets the weight of the voltage reference information.

3. According to claim 1, a microgrid group operating mode seamless switching control method based on hybrid auto-disturbance rejection is characterized in that: In step B, a frequency / voltage disturbance rejection recovery controller at the microgrid group level is designed to achieve fast synchronous tracking of the frequency / voltage of the microgrid group to the system rated reference value, which specifically includes the following steps: Step B01: For each controlled distributed power source at the microgrid group level, a frequency disturbance rejection and restoration controller at the microgrid group level is designed as follows: In the formula, Ω Hωk,pin For MG k The hybrid anti-disturbance output frequency adjustment value of the distributed power supply is controlled in the middle, Ω Lωk,pin The linear self-disturbance rejection output frequency adjustment corresponding to the distributed power supply is Ω Nωk,pin The corresponding nonlinear self-disturbance rejection output frequency adjustment value of the distributed power supply; ε ωk,pin b is the weight coefficient for controlling the frequency regulation of distributed power sources; ωk,pin To control the positive gain of the distributed power frequency regulation; k L1ωk,pin k is the frequency constant gain of the linear feedback controller for controlling distributed power supply; L2ωk,pin To control the frequency differential gain of the distributed power linear feedback controller; k N1ωk,pin k is the frequency constant gain of the nonlinear feedback controller for controlling distributed power generation; N2ωk,pin To control the frequency differential gain of the distributed power nonlinear feedback controller; L3ωk,pin Estimation of total disturbance for linear observer to control frequency regulation of distributed generation; N3ωk,pin To estimate the total disturbance of the nonlinear observer for the frequency regulation of distributed generation; ω * is the system rated frequency; The frequency derivative of the pinned distributed generation estimated by the linear observer; is the frequency differential component of the distributed generation estimated by the nonlinear observer; ρ′ N1ωk,pin The nonlinear factor that controls the nonlinear function of the frequency constant term of the distributed power supply; δ′ N1ωk,pin is the linear interval of the nonlinear function of the frequency constant term of the distributed power supply; ρ′ N2ωk,pin The nonlinear factor that controls the nonlinear function of the frequency differential term of the distributed power supply; δ′ N2ωk,pin The linear interval for controlling the nonlinear function of the frequency differential term of the distributed power supply; a kl For MG k Central control of distributed power generation and MG l The weight between distributed generation in the middle; g ωk,pin To control the weight of the distributed power generation to obtain the rated frequency information, Step B02: Based on the hybrid ADRC, the following average voltage observer is constructed for each distributed power source in the upper network: In the formula, u k,pin For MG k Control the output voltage of distributed power supply; is the weighted average voltage corresponding to the distributed generation; The weight coefficient for estimating the average voltage of distributed generation; To contain the positive gain of the average voltage estimate of the distributed generation; To control the average voltage constant gain of the distributed power linear feedback controller; To control the average voltage differential gain of the distributed power linear feedback controller; To control the average voltage constant gain of the distributed power nonlinear feedback controller; To control the average voltage differential gain of the distributed power nonlinear feedback controller; Estimation of total disturbance for linear observer to pin down average voltage estimation of distributed generation; Estimation of total disturbance for nonlinear observer to pin down average voltage estimation of distributed generation; The average voltage derivative of the distributed generation estimated by the linear observer; The average voltage derivative of the pinned distributed generation estimated by the nonlinear observer; The nonlinear factor for restraining the nonlinear function of the average voltage constant term of the distributed generation; To control the linear interval of the nonlinear function of the average voltage constant term of the distributed generation; The nonlinear factor to control the nonlinear function of the average voltage differential term of the distributed generation; To control the linear interval of the nonlinear function of the average voltage differential term of distributed generation, Step B03: Based on the average voltage observer, an average voltage recovery controller for each distributed power source at the microgrid group level is constructed as follows: In the formula, Φ Huk,pin For MG k The hybrid auto-disturbance rejection output voltage regulation of the distributed power supply is controlled by Φ Luk,pin To correspond to the linear self-disturbance rejection output voltage regulation of the distributed power supply, Φ Nuk,pin To control the nonlinear self-disturbance rejection output voltage regulation of distributed power sources; ε uk,pin b is the weight coefficient for controlling the voltage regulation of distributed power supply; uk,pin To control the positive gain of the distributed power supply voltage regulation; k L1uk,pin k is the voltage constant gain of the distributed power linear feedback controller; L2uk,pin To control the voltage differential gain of the distributed power linear feedback controller; k N1uk,pin k is the voltage constant gain of the distributed power nonlinear feedback controller; N2uk,pin To control the voltage differential gain of the distributed power nonlinear feedback controller; L3uk,pin Estimation of total disturbance for linear observer to control distributed generation voltage regulation; N3uk,pin Estimation of total disturbance for nonlinear observer to control distributed generation voltage regulation; is the system rated voltage; The average voltage derivative of the distributed generation estimated by the linear observer; The average voltage derivative of the pinned distributed generation estimated by the nonlinear observer; ρ′ N1uk,pin The nonlinear factor to control the nonlinear function of the voltage constant term of the distributed power supply; δ′ N1uk,pin is the linear interval of the nonlinear function of the voltage constant term of the distributed power supply; ρ′ N2uk,pin The nonlinear factor to control the nonlinear function of the differential term of the distributed power supply voltage; δ′ N2uk,pin g is the linear interval for controlling the nonlinear function of the differential term of the distributed power supply voltage; uk,pin The weight of obtaining rated voltage information for controlling distributed generation.

4. According to claim 1, a microgrid group operating mode seamless switching control method based on hybrid active disturbance rejection is characterized in that: In step C, active / reactive power control at the microgrid layer and the microgrid group layer is combined to enable all distributed power sources in the microgrid group to achieve uniform output of active and reactive power according to their capacities, which specifically includes the following steps: Step C01: Based on the lower layer network, construct a power sharing controller in the microgrid according to the following formula: In the formula, Unconstrained Distributed Generation Active power regulation; Unconstrained Distributed Generation Reactive power regulation; and They are Positive control gain for active and reactive power regulation; and They are Active and reactive power droop coefficients; and They are Output active and reactive power; m k,pin and n k,pin MG k The active and reactive power droop coefficients of distributed generation are controlled; P k,pin , and Q k,pin They are used to control the output active and reactive power of distributed power sources respectively; is the lower layer network G k The sth triggering moment, is the sth triggering moment of the upper network; and They are Get the weights of active and reactive power reference information, Step C02: Each controlled distributed power source exchanges the capacity information of its corresponding microgrid through the upper network. The power sharing controller at the microgrid group level is designed as follows: In the formula, Ω Pk,pin For MG k The active power regulation amount of the distributed power source is controlled; Φ Qk,pin For MG k The reactive power regulation of distributed power generation is controlled in the middle; k Pk,pin and k Qk,pin They are the positive control gains for controlling the active and reactive power regulation of distributed generation respectively.

5. The method for seamless switching control of microgrid operation modes based on hybrid auto-disturbance rejection according to claim 1 is characterized in that: In step D, a pre-synchronization controller is additionally designed by using hybrid active disturbance rejection to match the voltage and phase angle on both sides before the interconnection switch is closed, which specifically includes the following steps: Step D01: The difference between the dq axis components of the voltages on both sides of the interconnected switch represents the amplitude difference and phase angle difference. Then for the i-th distributed generation DG ki , the presynchronization controller can be expressed as: In the formula, Ω sk,i To superimpose on DG k,i The adjustment amount of the active power-frequency droop equation; Φ sk,i To superimpose on DG k,i The regulation quantity of reactive power-power droop equation; ξ k is the pre-synchronization start coefficient, if ξ k =1, indicating that the voltage / phase angle synchronization control is started on both sides of the interconnection, otherwise it is 0; and Respectively represent the voltage phase angle difference and amplitude difference on both sides of the switch to be closed; Ω Lsk,i is the phase angle adjustment value generated by the corresponding linear auto-disturbance rejection; Ω Nsk,i is the phase angle adjustment value generated by the nonlinear self-disturbance rejection; Φ Lsk,i is the amplitude adjustment value generated by the corresponding linear auto-disturbance rejection; Φ Nsk,i is the amplitude adjustment value generated by the corresponding nonlinear auto-disturbance rejection; ε sqk,i and ε sdk,i are the weight coefficients for phase angle and amplitude adjustment respectively; b sqk,i and b sdk,i are the positive gains for phase angle and amplitude adjustment respectively; k L1sqk,i is the phase angle constant gain of the linear feedback controller; k L2sqk,i is the phase differential gain of the linear feedback controller; k N1sqk,i is the phase angle constant gain of the nonlinear feedback controller; k N2sqk,i is the phase differential gain of the nonlinear feedback controller; k L1sdk,i is the amplitude constant gain of the linear feedback controller; k L2sdk,i is the amplitude differential gain of the linear feedback controller; k N1sdk,i is the amplitude constant gain of the nonlinear feedback controller; k N2sdk,i is the amplitude differential gain of the nonlinear feedback controller; ρ′ N1sqk,i is the nonlinear factor of the nonlinear function of the phase angle constant term; δ′ N1sqk,i is the linear interval of the nonlinear function of the phase angle constant term; ρ′ N2sqk,i is the nonlinear factor of the nonlinear function of the phase angle differential term; δ′ N2sqk,i is the linear interval of the nonlinear function of the phase angle differential term; ρ′ N1sdk,i is the nonlinear factor of the nonlinear function of the amplitude constant term; δ′ N1sdk,i is the linear interval of the nonlinear function of the amplitude constant term; ρ′ N2sdk,i is the nonlinear factor of the nonlinear function of the amplitude differential term; δ′ N2sdk,i is the linear interval of the nonlinear function of the amplitude differential term; z L3sqk,i Estimate the total disturbance for the phase-adjusted linear observer; z N3sqk,i Estimate the total disturbance for the phase-angle-adjusted nonlinear observer; z L3sdk,i is the linear estimated total disturbance adjusted by amplitude; z N3sdk,i Estimate the total disturbance for the amplitude-adjusted nonlinear observer, Step D02: Before the system performs the microgrid merging and interconnection operation, set ψ k is the interconnection switch symbol between different microgrids, ψ k =1 means the voltage and phase angle on both sides of the switch are inconsistent, and the switch is disconnected; ψ k =0 means that the voltage and phase angle on both sides of the switch are consistent and the switch is closed.

6. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the program, a seamless switching control method for operating modes of a microgrid group based on hybrid active disturbance rejection is implemented as described in any one of claims 1 to 5 above.

7. A computer-readable storage medium having computer instructions stored thereon, characterized in that: When the computer instruction is executed by the processor, a seamless switching control method for operating modes of a microgrid group based on hybrid active disturbance rejection is implemented as described in any one of claims 1-5.

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