A virtual synchronous control method, device and controller for a wind turbine generator set

Abstract

The present invention relates to a virtual synchronous control method, device and controller for a wind turbine generator set. The method includes: determining the grid connection point voltage amplitude of the wind turbine generator set according to the actual active power output and the actual reactive power output of the wind turbine generator set; determining the reactive power reference value of the wind turbine generator set according to the grid connection point voltage amplitude of the wind turbine generator set; determining the reference value of the internal electromotive force amplitude of the wind turbine generator set according to the active power reference value of the wind turbine generator set; determining the d / q axis components of the rotor current reference value of the wind turbine generator set according to the reference value of the internal electromotive force amplitude of the wind turbine generator set; determining the d / q axis components of the rotor voltage reference value of the wind turbine generator set according to the d / q axis components of the rotor current reference value of the wind turbine generator set; determining the PWM signal for controlling the wind turbine generator set according to the d / q axis components of the rotor voltage reference value of the wind turbine generator set, and controlling the wind turbine generator set by using the PWM signal. The technical solution provided by the present invention takes into account the influence of the transformer impedance, can smoothly adjust the reactive power of the wind turbine generator set according to the grid connection point voltage, and realizes the reactive power voltage regulation control.

Description

Technical Field

[0001] The present invention relates to the field of new energy access and control, and particularly relates to a virtual synchronous control method, device and controller for a wind turbine generator set. Background Art

[0002] To address the challenges of large-scale wind power / photovoltaic grid-connected safe and stable operation, drawing on the excellent characteristics of traditional synchronous units, domestic and foreign scholars have proposed the concept of Virtual Synchronous Generator (VSG). This technology can simulate the electromechanical transient characteristics of synchronous generator sets, enabling power supplies using converters to have grid-connected operating external characteristics such as the inertia, damping, primary frequency regulation, and reactive power voltage regulation of synchronous generator sets, thereby achieving the friendly access of new energy.

[0003] Currently, the research and application of virtual synchronous generators mainly focus on the microgrid field and the grid-connected control of photovoltaic systems. For the virtual synchronous technology of wind power systems, especially for doubly-fed wind power grid-connected systems, there are relatively few studies. And the currently mainstream research adopts the voltage-source type wind power virtual synchronous control method. However, currently, wind power usually grid-connects in the form of a current source with traditional vector control. Therefore, it is difficult to achieve large-scale grid engineering applications. Summary of the Invention

[0004] Aiming at the deficiencies of the prior art, the purpose of the present invention is to consider the influence of transformer impedance and be able to smoothly adjust the reactive power of the wind turbine generator set according to the grid connection point voltage, so as to achieve reactive power voltage regulation control.

[0005] The purpose of the present invention is achieved by the following technical solutions:

[0006] A virtual synchronous control method for a wind turbine generator set, wherein the improvement lies in that the method includes:

[0007] Determine the grid connection point voltage amplitude of the wind turbine generator set according to the actual active power output and the actual reactive power output of the wind turbine generator set;

[0008] Determine the reactive power reference value of the wind turbine generator set according to the grid connection point voltage amplitude of the wind turbine generator set;

[0009] Determine the reference value of the internal electromotive force amplitude of the wind turbine generator set according to the reference value of the active power of the wind turbine generator set;

[0010] Determine the d / q axis components of the reference value of the rotor current of the wind turbine generator set according to the reference value of the internal electromotive force amplitude of the wind turbine generator set;

[0011] Determine the d / q axis components of the reference value of the rotor voltage of the wind turbine generator set according to the d / q axis components of the reference value of the rotor current of the wind turbine generator set;

[0012] Determine the PWM signal for controlling the wind turbine according to the d / q axis components of the rotor voltage reference value of the wind turbine, and use this PWM signal to control the wind turbine.

[0013] Preferably, determining the grid connection point voltage amplitude of the wind turbine according to the actual active power output and the actual reactive power output of the wind turbine includes:

[0014] Determine the grid connection point voltage amplitude U of the wind turbine according to the following formula g :

[0015]

[0016] where k is the transformer turns ratio coefficient, U s is the stator voltage amplitude of the wind turbine, P mea is the actual active power output of the wind turbine, R T is the equivalent resistance of the transformer, Q mea is the actual reactive power output of the wind turbine, X T is the equivalent reactance of the transformer.

[0017] Preferably, determining the reactive power reference value of the wind turbine according to the grid connection point voltage amplitude of the wind turbine includes:

[0018] Determine the reactive power reference value Q of the wind turbine according to the following formula ref :

[0019] Q ref = Q0 + τ q (U n - U g )

[0020] where Q0 is the initial reactive power of the wind turbine, τ q is the reactive voltage droop coefficient, U n is the rated value of the grid connection point voltage of the wind turbine, U g is the grid connection point voltage amplitude of the wind turbine.

[0021] Preferably, determining the reference value of the internal electromotive force amplitude of the wind turbine according to the reference value of the active power of the wind turbine includes:

[0022] Determine the reference value E' of the internal electromotive force amplitude of the wind turbine according to the following formula * :

[0023]

[0024] where k vp is the proportional coefficient of the reactive power control loop, k vi is the integral coefficient of the reactive power control loop, s is the Laplace operator, Q refis the reactive power reference value of the wind turbine, Q mea is the actual reactive power output of the wind turbine.

[0025] Preferably, determining the d / q axis components of the rotor current reference value of the wind turbine according to the internal potential amplitude reference value of the wind turbine includes:

[0026] Determine the d-axis component of the rotor current reference value of the wind turbine according to the following formula

[0027]

[0028] Determine the q-axis component of the rotor current reference value of the wind turbine according to the following formula

[0029]

[0030] where, L m is the mutual inductance between the stator and rotor windings of the wind turbine, ω1 is the grid synchronous angular frequency, L r is the inductance of the rotor of the wind turbine, X' is the equivalent reactance of the wind turbine, E' * is the internal potential amplitude reference value of the wind turbine, θ vsg is the virtual synchronous machine position angle, θ s is the stator position angle of the wind turbine, U s is the stator voltage amplitude of the wind turbine.

[0031] Furthermore, determine the virtual synchronous machine position angle θ according to the following formula vsg :

[0032]

[0033] where, s is the Laplace operator, J vsg is the moment of inertia of the virtual synchronous machine, ω1 is the grid synchronous angular frequency, P ref is the active power reference value of the wind turbine, P mea is the actual active power output of the wind turbine, D vsg is the damping of the virtual synchronous machine, ω vsg is the angular frequency of the virtual synchronous machine.

[0034] Furthermore, determine the active power reference value P of the wind turbine according to the following formula ref :

[0035] P ref = P0 + τ p (ω n - ω1)

[0036] where, P0 is the initial active power of the wind turbine, τ pis the active power droop coefficient of the wind turbine, ω n is the rated angular frequency of the virtual synchronous machine, and ω1 is the grid synchronous angular frequency.

[0037] Further, the d / q axis components of the actual value of the stator voltage of the wind turbine are processed by a phase-locked loop to obtain the stator position angle θ s and the grid synchronous angular frequency ω1.

[0038] Further, the d-axis component u of the actual value of the stator voltage of the wind turbine is determined according to the following formula sd :

[0039] u sd = R s i sd - X'i sq + E'cosδ vsg

[0040] The q-axis component u of the actual value of the stator voltage of the wind turbine is determined according to the following formula sq :

[0041] u sq = R s i sq + X'i sd + E'sinδ vsg

[0042] where, R s is the resistance of the stator of the wind turbine, i sd is the d-axis component of the actual value of the stator current of the wind turbine, i sq the q-axis component of the actual value of the stator current of the wind turbine, X' is the equivalent reactance of the wind turbine, E' is the actual value of the internal electromotive force of the wind turbine, and δ vsg is the power angle of the virtual synchronous machine.

[0043] Further, θ is determined according to the following formula vsg - θ s :

[0044] θ vsg - θ s = ∫(ω vsg - ω1)dt

[0045] where, θ vsg is the position angle of the virtual synchronous machine, θ s is the stator position angle of the wind turbine, ω vsg is the angular frequency of the virtual synchronous machine, and ω1 is the grid synchronous angular frequency.

[0046] Preferably, determining the d / q axis components of the rotor voltage reference value of the wind turbine according to the d / q axis components of the rotor current reference value of the wind turbine includes:

[0047] Determine the d-axis component of the rotor voltage reference value of the wind turbine according to the following formula

[0048]

[0049] Determine the q-axis component of the rotor voltage reference value of the wind turbine according to the following formula

[0050]

[0051] Wherein, The proportional coefficient of the current inner loop, Is the integral coefficient of the current inner loop, s is the Laplace operator, Is the d-axis component of the rotor current reference value of the wind turbine, i rd Is the d-axis component of the actual rotor current of the wind turbine, Δu rd Is the d-axis component of the rotor voltage compensation of the wind turbine, Is the q-axis component of the rotor current reference value of the wind turbine, i rq Is the q-axis component of the actual rotor current of the wind turbine, Δu rq Is the q-axis component of the rotor voltage compensation of the wind turbine.

[0052] Furthermore, determine the d-axis component Δu of the rotor voltage compensation of the wind turbine according to the following formula rd :

[0053]

[0054] Determine the q-axis component Δu of the rotor voltage compensation of the wind turbine according to the following formula rq :

[0055]

[0056] Wherein, ω1 is the grid synchronous angular frequency, ω r Is the rotor angular frequency of the wind turbine, L m Is the mutual inductance between the stator and rotor windings of the wind turbine, L s Is the inductance of the stator of the wind turbine, U s Is the amplitude of the stator voltage of the wind turbine, X' is the equivalent reactance of the wind turbine, i rq Is the q-axis component of the actual rotor current of the wind turbine, i rd Is the d-axis component of the actual rotor current of the wind turbine.

[0057] Preferably, determining the PWM signal for controlling the wind turbine according to the d / q-axis components of the rotor voltage reference value of the wind turbine, and controlling the wind turbine by using the PWM signal includes:

[0058] Perform Clarke transformation on the d / q axis components of the rotor voltage reference value of the wind turbine generator set to obtain the α / β components of the rotor voltage reference value of the wind turbine generator set in the α / β coordinate system;

[0059] Perform space vector modulation on the α / β components of the rotor voltage reference value of the wind turbine generator set in the α / β coordinate system to obtain a PWM signal for controlling the wind turbine generator set, and use this PWM signal to control the wind turbine generator set.

[0060] A virtual synchronous control device for a wind turbine generator set, wherein the improvement lies in that the device includes:

[0061] A first determination unit for determining the grid connection point voltage amplitude of the wind turbine generator set according to the actual active power output and the actual reactive power output of the wind turbine generator set;

[0062] A second determination unit for determining the reactive power reference value of the wind turbine generator set according to the grid connection point voltage amplitude of the wind turbine generator set;

[0063] A third determination unit for determining the internal electromotive force amplitude reference value of the wind turbine generator set according to the active power reference value of the wind turbine generator set;

[0064] A fourth determination unit for determining the d / q axis components of the rotor current reference value of the wind turbine generator set according to the internal electromotive force amplitude reference value of the wind turbine generator set;

[0065] A fifth determination unit for determining the d / q axis components of the rotor voltage reference value of the wind turbine generator set according to the d / q axis components of the rotor current reference value of the wind turbine generator set;

[0066] A sixth determination unit for determining a PWM signal for controlling the wind turbine generator set according to the d / q axis components of the rotor voltage reference value of the wind turbine generator set, and using this PWM signal to control the wind turbine generator set.

[0067] A virtual synchronous controller for a wind turbine generator set, wherein the improvement lies in that the controller includes:

[0068] Wind turbine grid connection point voltage amplitude calculation module, first adder, first proportional controller, second adder, third adder, first PI controller, wind turbine rotor current reference value calculation module, fourth adder, second PI controller, fifth adder, α / β coordinate system transformation module, space vector modulation module, sixth adder, second proportional controller, seventh adder, eighth adder, first integral controller, second integral controller, ninth adder, multiplier, third proportional controller, tenth adder, third PI controller, eleventh adder, first d / q coordinate system transformation module, wind turbine rotor voltage compensation calculation module, differential controller, second d / q coordinate system transformation module, phase-locked loop, twelfth adder;

[0069] The wind turbine grid connection point voltage amplitude calculation module, first adder, first proportional controller, second adder, third adder, first PI controller, wind turbine rotor current reference value calculation module, fourth adder, second PI controller, fifth adder, α / β coordinate system transformation module, and space vector modulation module are connected in sequence;

[0070] The sixth adder, second proportional controller, seventh adder, eighth adder, first integral controller, second integral controller, wind turbine rotor current reference value calculation module, tenth adder, third PI controller, eleventh adder, α / β coordinate system transformation module, and space vector modulation module are connected in sequence;

[0071] The ninth adder, multiplier, third proportional controller, and eighth adder are connected in sequence;

[0072] The first d / q coordinate system transformation module is connected to the wind turbine rotor voltage compensation calculation module;

[0073] The differential controller is connected to the wind turbine in the power grid containing the wind turbine;

[0074] The second d / q coordinate system transformation module, phase-locked loop, and twelfth adder are connected in sequence;

[0075] The inputs of the wind turbine grid connection point voltage amplitude calculation module are P mea and Q mea ;

[0076] The inputs of the first adder are -U g and U n ;

[0077] The input of the first proportional controller is the output of the first adder, and the proportional coefficient of the first proportional controller is τ q ;

[0078] The input of the second adder is Q0 and the output of the first proportional controller;

[0079] The input of the third adder is -Q mea and the output of the second adder;

[0080] The input of the first PI controller is the output of the third adder;

[0081] The input of the wind turbine rotor current reference value calculation module is E' output by the first PI controller * , θ output by the second integral controller vsg , θ s and U s ;

[0082] The input of the fourth adder is the q-axis component of the wind turbine rotor current reference value output by the wind turbine rotor current reference value calculation module and -i rq ;

[0083] The input of the second PI control module is the output of the fourth adder;

[0084] The input of the fifth adder is the output of the second PI control and Δu rq ;

[0085] The input of the α / β coordinate system transformation module is the output of the fifth adder and the output of the eleventh adder;

[0086] The input of the space vector modulation module is the output of the α / β coordinate system transformation module, and the output of the space vector modulation module is the PWM signal for controlling the wind turbine;

[0087] The input of the sixth adder is -ω1 and ω n ;

[0088] The input of the second proportional controller is the output of the sixth adder and the proportional coefficient of the second proportional controller is τ p ;

[0089] The input of the seventh adder is the output of the second proportional controller and P0;

[0090] The input of the eighth adder is the output of the seventh adder, the output of the third proportional controller and -P mea ;

[0091] The input of the first integral controller is the output of the eighth adder and the integral coefficient of the first integral controller is

[0092] The input of the second integral controller is the output of the first integral controller, and the integral coefficient of the second integral controller is

[0093] The inputs of the ninth adder are -ω1 and the output of the first integral controller;

[0094] The inputs of the multiplier are the output of the ninth adder and ω1;

[0095] The input of the third proportional control is the output of the multiplier, and the proportional coefficient of the third proportional control is D vsg ;

[0096] The inputs of the tenth adder are the d-axis component of the reference value of the wind turbine generator rotor current output by the wind turbine generator rotor current reference value calculation module and -i rd ;

[0097] The input of the third PI controller is the output of the tenth adder;

[0098] The inputs of the eleventh adder are the output of the third PI controller and Δu rd ;

[0099] The inputs of the first d / q coordinate system transformation module are the a, b, c phase currents in the power grid containing the wind turbine generator and the output of the twelfth adder;

[0100] The inputs of the wind turbine generator rotor voltage compensation calculation module are the output of the first d / q coordinate system transformation module, the output of the microcontroller, ω1, and U s ;

[0101] The input of the differential controller is θ r ;

[0102] The inputs of the second d / q coordinate system transformation module are the a, b, c phase voltages in the power grid containing the wind turbine generator and θ s ;

[0103] The input of the phase-locked loop is the output of the second d / q coordinate system transformation module;

[0104] The inputs of the twelfth adder are θ s and θ r ;

[0105] where, P mea is the actual active power output of the wind turbine generator, Q mea is the actual reactive power output of the wind turbine generator, U s is the amplitude of the stator voltage of the wind turbine generator, Ug is the grid connection point voltage amplitude of the wind turbine generator set output by the grid connection point voltage amplitude calculation module of the wind turbine generator set, U n is the rated value of the grid connection point voltage of the wind turbine generator set, τ q is the reactive voltage droop coefficient, Q0 is the initial reactive power of the wind turbine generator set, Q mea is the actual output reactive power of the wind turbine generator set, θ s is the stator position angle of the wind turbine generator set, Δu rq is the q-axis component of the rotor voltage compensation of the wind turbine generator set output by the rotor voltage compensation calculation module of the wind turbine generator set, ω n is the rated angular frequency of the virtual synchronous machine, ω1 is the grid synchronous angular frequency, τ p is the active power droop coefficient of the wind turbine generator set, P0 is the initial active power of the wind turbine generator set, s is the Laplace operator, J vsg is the moment of inertia of the virtual synchronous machine, D vsg is the damping of the virtual synchronous machine, Δu rd is the d-axis component of the rotor voltage compensation of the wind turbine generator set output by the rotor voltage compensation calculation module of the wind turbine generator set, θ r is the rotor position angle of the wind turbine generator set, θ s is the stator position angle of the wind turbine generator set, θ vsg is the position angle of the virtual synchronous machine, i rq is the q-axis component of the actual value of the rotor current of the wind turbine generator set output by the first d / q coordinate system transformation module, i rd is the d-axis component of the actual value of the rotor current of the wind turbine generator set output by the first d / q coordinate system transformation module.

[0106] Compared with the closest prior art, the beneficial effects of the present invention are as follows:

[0107] The technical solution provided by the present invention fully considers the influence of the transformer impedance, and can smoothly adjust the reactive power of the wind turbine generator set according to the voltage at the connection point between the step-up transformer of the wind turbine generator set and the power grid, realizing the reactive voltage regulation control of the wind turbine generator set; the technical solution provided by the present invention adds a damping link, and can simulate the inertia, damping, reactive voltage regulation and primary frequency modulation functions of the traditional synchronous machine; the technical solution provided by the present invention is applicable to the current large power grid environment, and can avoid adverse factors such as power circulating current that may be caused by the virtual synchronous control grid connection of the voltage source type wind power in the prior art, and improve the grid friendliness. BRIEF DESCRIPTION OF THE DRAWINGS

[0108] Figure 1 is a flowchart of a virtual synchronous control method for a wind turbine generator set provided by the present invention;

[0109] Figure 2 is an equivalent circuit of a transformer provided by an embodiment of the present invention;

[0110] Figure 3 It is the virtual synchronous control vector relationship diagram provided by the embodiment of the present invention;

[0111] Figure 4 It is the schematic structural diagram of the virtual synchronous control device of a wind turbine provided by the present invention;

[0112] Figure 5 It is the control block diagram of the virtual synchronous controller of a wind turbine provided by the present invention. Specific embodiments

[0113] The following further elaborates on the specific embodiments of the present invention in conjunction with the accompanying drawings.

[0114] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Apparently, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0115] The present invention provides a virtual synchronous control method for a wind turbine, as Figure 1 shown, including:

[0116] 101. Determine the grid connection point voltage amplitude of the wind turbine according to the actual active power output and the actual reactive power output of the wind turbine, including:

[0117] Determine the grid connection point voltage amplitude U of the wind turbine according to the following formula g :

[0118]

[0119] where k is the transformer turns ratio coefficient, U s is the stator voltage amplitude of the wind turbine, P mea is the actual active power output of the wind turbine, R T is the equivalent resistance of the transformer, Q mea is the actual reactive power output of the wind turbine, and X T is the equivalent reactance of the transformer. As Figure 2 shown, it is the equivalent circuit of the transformer.

[0120] After determining the grid connection point voltage amplitude of the wind turbine, it is necessary to determine the reactive power reference value of the wind turbine according to the grid connection point voltage amplitude of the wind turbine. Therefore, step 102. Determine the reactive power reference value of the wind turbine according to the grid connection point voltage amplitude of the wind turbine, including:

[0121] Determine the reactive power reference value \(Q\) of the wind turbine generator set according to the following formula ref :

[0122] \(Q\) ref = \(Q_0+\tau\) q \((U\) n -\(U\) g )

[0123] where \(Q_0\) is the initial reactive power of the wind turbine generator set, and \(\tau\) q is the reactive voltage droop coefficient, \(U\) n is the rated voltage of the grid connection point of the wind turbine generator set, and \(U\) g is the amplitude of the grid connection point voltage of the wind turbine generator set.

[0124] After determining the reactive power reference value of the wind turbine generator set, it is necessary to determine the reference value of the internal potential amplitude of the wind turbine generator set according to the active power reference value of the wind turbine generator set. Therefore, step 103. Determine the reference value of the internal potential amplitude of the wind turbine generator set according to the active power reference value of the wind turbine generator set, includes:

[0125] Determine the reference value of the internal potential amplitude \(E'\) of the wind turbine generator set according to the following formula * :

[0126]

[0127] where \(k\) vp is the proportional coefficient of the reactive power control loop, \(k\) vi is the integral coefficient of the reactive power control loop, \(s\) is the Laplace operator, \(Q\) ref is the reactive power reference value of the wind turbine generator set, and \(Q\) mea is the actual reactive power output of the wind turbine generator set.

[0128] As Figure 3 shown, it is the virtual synchronous control vector relationship diagram. The stator voltage amplitude \(U\) s of the wind turbine generator set rotates at the grid synchronous angular frequency \(\omega_1\) in the synchronous rotating \(d / q\) coordinate system, and the stator position angle of the wind turbine generator set is \(\theta\) s ; the actual value \(E'\) of the internal potential of the wind turbine generator set rotates at the virtual synchronous machine angular frequency \(\omega\) vsg in the synchronous rotating \(d / q\) coordinate system, and the virtual synchronous machine position angle is \(\theta\) vsg , and the actual value \(E'\) of the internal potential of the wind turbine generator set leads the rotor magnetic flux vector \(\psi\) r by \(90^{\circ}\); the rotor of the wind turbine generator set rotates at the rotor angular frequency \(\omega\) r , and the rotor position angle of the wind turbine generator set is \(\theta\) r .

[0129] After determining the reference value of the potential amplitude within the wind turbine generator set, it is necessary to determine the d / q-axis components of the reference value of the rotor current of the wind turbine generator set according to the reference value of the potential amplitude within the wind turbine generator set. Therefore, step 104. Determining the d / q-axis components of the reference value of the rotor current of the wind turbine generator set according to the reference value of the potential amplitude within the wind turbine generator set includes:

[0130] Determine the d-axis component of the reference value of the rotor current of the wind turbine generator set according to the following formula

[0131]

[0132] Determine the q-axis component of the reference value of the rotor current of the wind turbine generator set according to the following formula

[0133]

[0134] where, L m is the mutual inductance between the stator and rotor windings of the wind turbine generator set, ω1 is the grid synchronous angular frequency, L r is the inductance of the rotor of the wind turbine generator set, X' is the equivalent reactance of the wind turbine generator set, E' * is the reference value of the potential amplitude within the wind turbine generator set, θ vsg is the virtual synchronous machine position angle, θ s is the stator position angle of the wind turbine generator set, U s is the amplitude of the stator voltage of the wind turbine generator set.

[0135] Determine the virtual synchronous machine position angle θ according to the following formula vsg :

[0136]

[0137] where, s is the Laplace operator, J vsg is the moment of inertia of the virtual synchronous machine, ω1 is the grid synchronous angular frequency, P ref is the reference value of the active power of the wind turbine generator set, P mea is the actual output active power of the wind turbine generator set, D vsg is the damping of the virtual synchronous machine, ω vsg is the angular frequency of the virtual synchronous machine.

[0138] Determine the reference value of the active power of the wind turbine generator set P according to the following formula ref :

[0139] P ref = P0 + τ p (ω n - ω1)

[0140] where, P0 is the initial active power of the wind turbine generator set, τ p is the active power droop coefficient of the wind turbine generator set, ωn is the rated angular frequency of the virtual synchronous machine, and ω1 is the grid synchronous angular frequency.

[0141] The d / q-axis components of the actual stator voltage of the wind turbine are processed by a phase-locked loop to obtain the stator position angle θ s of the wind turbine and the grid synchronous angular frequency ω1.

[0142] Determine the d-axis component u of the actual stator voltage of the wind turbine according to the following formula sd :

[0143] u sd = R s i sd - X'i sq + E'cosδ vsg

[0144] Determine the q-axis component u of the actual stator voltage of the wind turbine according to the following formula sq :

[0145] u sq = R s i sq + X'i sd + E'sinδ vsg

[0146] Where, R s is the resistance of the stator of the wind turbine, i sd is the d-axis component of the actual stator current of the wind turbine, i sq is the q-axis component of the actual stator current of the wind turbine, X' is the equivalent reactance of the wind turbine, E' is the actual value of the internal electromotive force of the wind turbine, and δ vsg is the power angle of the virtual synchronous machine.

[0147] Determine θ according to the following formula vsg - θ s :

[0148] θ vsg - θ s = ∫(ω vsg - ω1)dt

[0149] Where, θ vsg is the position angle of the virtual synchronous machine, θ s is the stator position angle of the wind turbine, ω vsg is the angular frequency of the virtual synchronous machine, and ω1 is the grid synchronous angular frequency.

[0150] After determining the d / q-axis components of the rotor current reference value of the wind turbine generator set, it is necessary to determine the d / q-axis components of the rotor voltage reference value of the wind turbine generator set according to the d / q-axis components of the rotor current reference value of the wind turbine generator set. Therefore, step 105. Determining the d / q-axis components of the rotor voltage reference value of the wind turbine generator set according to the d / q-axis components of the rotor current reference value of the wind turbine generator set includes:

[0151] Determine the d-axis component of the rotor voltage reference value of the wind turbine generator set according to the following formula

[0152]

[0153] Determine the q-axis component of the rotor voltage reference value of the wind turbine generator set according to the following formula

[0154]

[0155] Wherein, The proportional coefficient of the current inner loop, Is the integral coefficient of the current inner loop, s is the Laplace operator, Is the d-axis component of the rotor current reference value of the wind turbine generator set, i rd Is the d-axis component of the actual rotor current value of the wind turbine generator set, Δu rd Is the d-axis component of the rotor voltage compensation, Is the q-axis component of the rotor current reference value of the wind turbine generator set, i rq Is the q-axis component of the actual rotor current value of the wind turbine generator set, Δu rq Is the q-axis component of the rotor voltage compensation.

[0156] Determine the d-axis component Δu of the rotor voltage compensation of the wind turbine generator set according to the following formula rd :

[0157]

[0158] Determine the q-axis component Δu of the rotor voltage compensation of the wind turbine generator set according to the following formula rq :

[0159]

[0160] Wherein, ω1 is the grid synchronous angular frequency, ω r Is the rotor angular frequency of the wind turbine generator set, L m Is the mutual inductance between the stator and rotor windings of the wind turbine generator set, L s Is the inductance of the stator of the wind turbine generator set, U s Is the amplitude of the stator voltage of the wind turbine generator set, X' is the equivalent reactance of the wind turbine generator set, i rq Is the q-axis component of the actual rotor current value of the wind turbine generator set, ird is the d-axis component of the actual rotor current of the wind turbine generator set.

[0161] After determining the d / q-axis components of the reference rotor voltage of the wind turbine generator set, it is necessary to determine the PWM signal for controlling the wind turbine generator set according to the d / q-axis components of the reference rotor voltage of the wind turbine generator set, and use this PWM signal to control the wind turbine generator set. Therefore, step 106. Determine the PWM signal for controlling the wind turbine generator set according to the d / q-axis components of the reference rotor voltage of the wind turbine generator set, and use this PWM signal to control the wind turbine generator set, includes:

[0162] Perform Clarke transformation on the d / q-axis components of the reference rotor voltage of the wind turbine generator set to obtain the α / β components of the reference rotor voltage of the wind turbine generator set in the α / β coordinate system;

[0163] Perform space vector modulation on the α / β components of the reference rotor voltage of the wind turbine generator set in the α / β coordinate system to obtain the PWM signal for controlling the wind turbine generator set, and use this PWM signal to control the wind turbine generator set.

[0164] Based on the same concept of the above method, the present invention also provides a virtual synchronous control device for a wind turbine generator set, as Figure 4 shown, the device includes:

[0165] The first determination unit is used to determine the grid connection point voltage amplitude of the wind turbine generator set according to the actual active power output and the actual reactive power output of the wind turbine generator set;

[0166] The second determination unit is used to determine the reference reactive power value of the wind turbine generator set according to the grid connection point voltage amplitude of the wind turbine generator set;

[0167] The third determination unit is used to determine the reference value of the internal electromotive force amplitude of the wind turbine generator set according to the reference active power value of the wind turbine generator set;

[0168] The fourth determination unit is used to determine the d / q-axis components of the reference rotor current of the wind turbine generator set according to the reference value of the internal electromotive force amplitude of the wind turbine generator set;

[0169] The fifth determination unit is used to determine the d / q-axis components of the reference rotor voltage of the wind turbine generator set according to the d / q-axis components of the reference rotor current of the wind turbine generator set;

[0170] The sixth determination unit is used to determine the PWM signal for controlling the wind turbine generator set according to the d / q-axis components of the reference rotor voltage of the wind turbine generator set, and use this PWM signal to control the wind turbine generator set.

[0171] The present invention also provides a virtual synchronous controller for a wind turbine generator set, as Figure 5 shown, the controller includes:

[0172] Wind turbine grid connection point voltage amplitude calculation module, first adder, first proportional controller, second adder, third adder, first PI controller, wind turbine rotor current reference value calculation module, fourth adder, second PI controller, fifth adder, α / β coordinate system transformation module, space vector modulation module, sixth adder, second proportional controller, seventh adder, eighth adder, first integral controller, second integral controller, ninth adder, multiplier, third proportional controller, tenth adder, third PI controller, eleventh adder, first d / q coordinate system transformation module, wind turbine rotor voltage compensation calculation module, differential controller, second d / q coordinate system transformation module, phase-locked loop, twelfth adder;

[0173] The wind turbine grid connection point voltage amplitude calculation module, first adder, first proportional controller, second adder, third adder, first PI controller, wind turbine rotor current reference value calculation module, fourth adder, second PI controller, fifth adder, α / β coordinate system transformation module, and space vector modulation module are connected in sequence;

[0174] The sixth adder, second proportional controller, seventh adder, eighth adder, first integral controller, second integral controller, wind turbine rotor current reference value calculation module, tenth adder, third PI controller, eleventh adder, α / β coordinate system transformation module, and space vector modulation module are connected in sequence;

[0175] The ninth adder, multiplier, third proportional controller, and eighth adder are connected in sequence;

[0176] The first d / q coordinate system transformation module is connected to the wind turbine rotor voltage compensation calculation module;

[0177] The differential controller is connected to the wind turbine in the power grid containing the wind turbine;

[0178] The second d / q coordinate system transformation module, phase-locked loop, and twelfth adder are connected in sequence;

[0179] The input of the wind turbine grid connection point voltage amplitude calculation module is P mea and Q mea ;

[0180] The input of the first adder is -U g and U n ;

[0181] The input of the first proportional controller is the output of the first adder and the proportional coefficient of the first proportional controller is τ q ;

[0182] The inputs of the second adder are Q0 and the output of the first proportional controller;

[0183] The inputs of the third adder are -Q mea and the output of the second adder;

[0184] The input of the first PI controller is the output of the third adder;

[0185] The inputs of the wind turbine rotor current reference value calculation module are E' output by the first PI controller * and θ output by the second integral controller vsg θ s and U s ;

[0186] The inputs of the fourth adder are the q-axis component of the wind turbine rotor current reference value output by the wind turbine rotor current reference value calculation module and -i rq ;

[0187] The input of the second PI control module is the output of the fourth adder;

[0188] The inputs of the fifth adder are the output of the second PI control and Δu rq ;

[0189] The inputs of the α / β coordinate system transformation module are the output of the fifth adder and the output of the eleventh adder;

[0190] The input of the space vector modulation module is the output of the α / β coordinate system transformation module, and the output of the space vector modulation module is the PWM signal for controlling the wind turbine;

[0191] The inputs of the sixth adder are -ω1 and ω n ;

[0192] The input of the second proportional controller is the output of the sixth adder and the proportional coefficient of the second proportional controller is τ p ;

[0193] The inputs of the seventh adder are the output of the second proportional controller and P0;

[0194] The inputs of the eighth adder are the output of the seventh adder, the output of the third proportional controller and -P mea ;

[0195] The input of the first integral controller is the output of the eighth adder and the integral coefficient of the first integral controller is

[0196] The input of the second integral controller is the output of the first integral controller, and the integral coefficient of the second integral controller is

[0197] The inputs of the ninth adder are -ω1 and the output of the first integral controller;

[0198] The inputs of the multiplier are the output of the ninth adder and ω1;

[0199] The input of the third proportional control is the output of the multiplier, and the proportional coefficient of the third proportional control is D vsg ;

[0200] The inputs of the tenth adder are the d-axis component of the reference value of the wind turbine rotor current output by the wind turbine rotor current reference value calculation module and -i rd ;

[0201] The input of the third PI controller is the output of the tenth adder;

[0202] The inputs of the eleventh adder are the output of the third PI controller and Δu rd ;

[0203] The inputs of the first d / q coordinate transformation module are the a, b, c phase currents in the power grid containing the wind turbine and the output of the twelfth adder;

[0204] The inputs of the wind turbine rotor voltage compensation calculation module are the output of the first d / q coordinate transformation module, the output of the microcontroller, ω1 and U s ;

[0205] The input of the differential controller is θ r ;

[0206] The inputs of the second d / q coordinate transformation module are the a, b, c phase voltages in the power grid containing the wind turbine and θ s ;

[0207] The input of the phase-locked loop is the output of the second d / q coordinate transformation module;

[0208] The inputs of the twelfth adder are θ s and θ r ;

[0209] where, P mea is the actual active power output by the wind turbine, Q mea is the actual reactive power output by the wind turbine, U sis the stator voltage amplitude of the wind turbine, U g is the grid connection point voltage amplitude of the wind turbine output by the grid connection point voltage amplitude calculation module of the wind turbine, U n is the rated value of the grid connection point voltage of the wind turbine, τ q is the reactive voltage droop coefficient, Q0 is the initial reactive power of the wind turbine, Q mea is the actual reactive power output of the wind turbine, θ s is the stator position angle of the wind turbine, Δu rq is the q-axis component of the rotor voltage compensation of the wind turbine output by the rotor voltage compensation calculation module of the wind turbine, ω n is the rated angular frequency of the virtual synchronous machine, ω1 is the grid synchronous angular frequency, τ p is the active power droop coefficient of the wind turbine, P0 is the initial active power of the wind turbine, s is the Laplace operator, J vsg is the moment of inertia of the virtual synchronous machine, D vsg is the damping of the virtual synchronous machine, Δu rd is the d-axis component of the rotor voltage compensation of the wind turbine output by the rotor voltage compensation calculation module of the wind turbine, θ r is the rotor position angle of the wind turbine, θ s is the stator position angle of the wind turbine, θ vsg is the position angle of the virtual synchronous machine, i rq is the q-axis component of the actual value of the rotor current of the wind turbine output by the first d / q coordinate system transformation module, i rd is the d-axis component of the actual value of the rotor current of the wind turbine output by the first d / q coordinate system transformation module.

[0210] Those skilled in the art should understand that the embodiments of the present application can be provided as methods, systems, or computer program products. Therefore, the present application can take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present application can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0211] This application is described with reference to the flowcharts and / or block diagrams of methods, apparatuses (systems), and computer program products according to embodiments of the present application. It should be understood that each flow and / or block in the flowcharts and / or block diagrams, as well as the combination of flows and / or blocks in the flowcharts and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to the processors of general-purpose computers, special-purpose computers, embedded processors, or other programmable data processing devices to generate a machine, such that the instructions executed by the processors of the computer or other programmable data processing devices generate means for implementing the functions specified in one or more of the flows Figure 1 one or more of the flows and / or blocks Figure 1 or means for implementing the functions specified in one or more of the blocks.

[0212] These computer program instructions can also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to work in a specific manner, such that the instructions stored in the computer-readable memory generate a manufactured article including instruction means for implementing the functions specified in one or more of the flows Figure 1 one or more of the flows and / or blocks Figure 1 or means for implementing the functions specified in one or more of the blocks.

[0213] These computer program instructions can also be loaded onto a computer or other programmable data processing device, such that a series of operational steps are executed on the computer or other programmable device to generate a computer-implemented process, and thus the instructions executed on the computer or other programmable device provide steps for implementing the functions specified in one or more of the flows Figure 1 one or more of the flows and / or blocks Figure 1 or means for implementing the functions specified in one or more of the blocks.

[0214] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to the above embodiments, those of ordinary skill in the art should understand that: modifications or equivalent substitutions can still be made to the specific embodiments of the present invention, and any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered by the protection scope of the claims of the present invention.

Claims

1. A virtual synchronous control method for a wind turbine, characterized in that, The method includes: Determining the voltage amplitude at the grid connection point of the wind turbine according to the actual active power output and the actual reactive power output of the wind turbine; Determining the reference value of the reactive power of the wind turbine according to the voltage amplitude at the grid connection point of the wind turbine; Determining the reference value of the internal potential amplitude of the wind turbine according to the reference value of the active power of the wind turbine; Determining the d / q axis components of the reference value of the rotor current of the wind turbine according to the reference value of the internal potential amplitude of the wind turbine; Determining the d / q axis components of the reference value of the rotor voltage of the wind turbine according to the d / q axis components of the reference value of the rotor current of the wind turbine; Determining the PWM signal for controlling the wind turbine according to the d / q axis components of the reference value of the rotor voltage of the wind turbine, and controlling the wind turbine by using the PWM signal; The determining the voltage amplitude at the grid connection point of the wind turbine according to the actual active power output and the actual reactive power output of the wind turbine includes: Determine the grid connection point voltage amplitude of the wind turbine according to the following formula : Among them, is the transformer turns ratio coefficient, is the stator voltage amplitude of the wind turbine generator set, is the actual active power output of the wind turbine generator set, is the equivalent resistance of the transformer, is the actual reactive power output of the wind turbine generator set, is the equivalent reactance of the transformer; The determining the reference value of the internal potential amplitude of the wind turbine according to the reference value of the active power of the wind turbine includes: Determine the reference value of the potential amplitude in the wind turbine according to the following formula : Among them, is the proportional coefficient of the reactive power control loop, is the integral coefficient of the reactive power control loop, is the Laplace operator, is the reactive power reference value of the wind turbine generator set, is the actual reactive power output of the wind turbine generator set; The determining the d / q axis components of the reference value of the rotor current of the wind turbine according to the reference value of the internal potential amplitude of the wind turbine includes: Determine the d-axis component of the rotor current reference value of the wind turbine according to the following formula : Determine the q-axis component of the rotor current reference value of the wind turbine according to the following formula : Among them, is the mutual inductance between the stator and rotor windings of the wind turbine generator,[ is the synchronous angular frequency of the power grid,[ is the inductance of the rotor of the wind turbine generator,[ is the equivalent reactance of the wind turbine generator,[ is the reference value of the amplitude of the internal electromotive force of the wind turbine generator,[ is the position angle of the virtual synchronous machine,[ is the stator position angle of the wind turbine generator,[ is the amplitude of the stator voltage of the wind turbine generator.[ 2. The method according to claim 1, characterized in that, The determining the reference value of the reactive power of the wind turbine according to the voltage amplitude at the grid connection point of the wind turbine includes: Determine the reference value of the reactive power of the wind turbine according to the following formula : Among them, is the initial reactive power of the wind turbine generator set, is the reactive voltage droop coefficient, is the rated voltage of the point of common coupling of the wind turbine generator set, is the amplitude of the voltage at the point of common coupling of the wind turbine generator set.

3. The method according to claim 1, characterized in that, Determine the position angle of the virtual synchronous machine according to the following formula :[[]]END]] Among them, is the Laplacian operator, is the moment of inertia of the virtual synchronous generator, is the grid synchronous angular frequency, is the reference value of the active power of the wind turbine, is the actual output active power of the wind turbine, is the damping of the virtual synchronous generator, is the angular frequency of the virtual synchronous generator.

4. The method according to claim 3, characterized in that, Determine the reference value of the active power of the wind turbine according to the following formula : Among them, is the initial active power of the wind turbine,[ is the active power droop coefficient of the wind turbine,[ is the rated angular frequency of the virtual synchronous machine,[ is the grid synchronous angular frequency.[ 5. The method according to claim 1, characterized in that, The d / q axis components of the actual stator voltage of the wind turbine are processed by a phase-locked loop to obtain the stator position angle of the wind turbine and the grid synchronous angular frequency .

6. The method according to claim 5, characterized in that, Determine the d-axis component of the actual value of the stator voltage of the wind turbine according to the following formula : Determine the q-axis component of the actual value of the stator voltage of the wind turbine according to the following formula :[[]]END]] Among them, is the resistance of the stator of the wind turbine generator set, is the d-axis component of the actual value of the stator current of the wind turbine generator set, the q-axis component of the actual value of the stator current of the wind turbine generator set, is the equivalent reactance of the wind turbine generator set, is the actual value of the internal electromotive force of the wind turbine generator set, is the power angle of the virtual synchronous machine.

7. The method according to claim 1, characterized in that Determine according to the following formula : Among them, is the position angle of the virtual synchronous machine, is the stator position angle of the wind turbine generator set, is the angular frequency of the virtual synchronous machine, is the grid synchronous angular frequency.

8. The method according to claim 1, characterized in that The determining the d / q axis components of the reference value of the rotor voltage of the wind turbine according to the d / q axis components of the reference value of the rotor current of the wind turbine includes: Determine the d-axis component of the rotor voltage reference value of the wind turbine according to the following formula : Determine the q-axis component of the rotor voltage reference value of the wind turbine according to the following formula Among them, The proportional coefficient of the inner current loop, is the integral coefficient of the inner current loop, is the Laplace operator, is the d-axis component of the reference value of the rotor current of the wind turbine, is the d-axis component of the actual value of the rotor current of the wind turbine, is the d-axis component of the rotor voltage compensation of the wind turbine, is the q-axis component of the reference value of the rotor current of the wind turbine, is the q-axis component of the actual value of the rotor current of the wind turbine, is the q-axis component of the rotor voltage compensation of the wind turbine.

9. The method according to claim 8, characterized in that Determine the d-axis component of the rotor voltage compensation of the wind turbine according to the following formula : Determine the q-axis component of the rotor voltage compensation of the wind turbine according to the following formula : Among them, is the grid synchronous angular frequency, is the rotor angular frequency of the wind turbine generator set, is the mutual inductance between the stator and rotor windings of the wind turbine generator set, is the inductance of the stator of the wind turbine generator set, is the amplitude of the stator voltage of the wind turbine generator set, is the equivalent reactance of the wind turbine generator set, is the q-axis component of the actual value of the rotor current of the wind turbine generator set, is the d-axis component of the actual value of the rotor current of the wind turbine generator set.

10. The method according to claim 1, characterized in that The determining the PWM signal for controlling the wind turbine according to the d / q axis components of the reference value of the rotor voltage of the wind turbine, and controlling the wind turbine by using the PWM signal includes: Perform a Clarke transformation on the d / q axis components of the rotor voltage reference value of the wind turbine generator set to obtain / the / components of the rotor voltage reference value of the wind turbine generator set in the coordinate system; For the / components of the rotor voltage reference value of the wind turbine under the coordinate system / perform space vector modulation to obtain a PWM signal for controlling the wind turbine, and use this PWM signal to control the wind turbine.

11. A virtual synchronous control device for a wind turbine generator set for implementing the method according to claim 1, characterized in that The device includes: A first determination unit for determining the voltage amplitude at the grid connection point of the wind turbine according to the actual active power output and the actual reactive power output of the wind turbine; A second determination unit for determining the reference value of the reactive power of the wind turbine according to the voltage amplitude at the grid connection point of the wind turbine; A third determination unit for determining the reference value of the internal potential amplitude of the wind turbine according to the reference value of the active power of the wind turbine; A fourth determination unit for determining the d / q axis components of the reference value of the rotor current of the wind turbine according to the reference value of the internal potential amplitude of the wind turbine; A fifth determination unit for determining the d / q axis components of the reference value of the rotor voltage of the wind turbine according to the d / q axis components of the reference value of the rotor current of the wind turbine; A sixth determination unit for determining the PWM signal for controlling the wind turbine according to the d / q axis components of the reference value of the rotor voltage of the wind turbine, and controlling the wind turbine by using the PWM signal.

12. The device according to claim 11, characterized in that The device includes: a virtual synchronous controller; Wherein, the virtual synchronous controller includes: Wind turbine grid connection point voltage amplitude calculation module, first adder, first proportional controller, second adder, third adder, first PI controller, wind turbine rotor current reference value calculation module, fourth adder, second PI controller, fifth adder, / Coordinate system transformation module, space vector modulation module, sixth adder, second proportional controller, seventh adder, eighth adder, first integral controller, second integral controller, ninth adder, multiplier, third proportional controller, tenth adder, third PI controller, eleventh adder, first d / q coordinate system transformation module, wind turbine rotor voltage compensation calculation module, differential controller, second d / q coordinate system transformation module, phase-locked loop, twelfth adder; The grid connection point voltage amplitude calculation module of the wind turbine generator set, the first adder, the first proportional controller, the second adder, the third adder, the first PI controller, the rotor current reference value calculation module of the wind turbine generator set, the fourth adder, the second PI controller, the fifth adder / The coordinate system transformation module and the space vector modulation module are connected in sequence; The sixth adder, the second proportional controller, the seventh adder, the eighth adder, the first integral controller, the second integral controller, the wind turbine rotor current reference value calculation module, the tenth adder, the third PI controller, the eleventh adder, / The coordinate system transformation module and the space vector modulation module are connected in sequence; The ninth adder, multiplier, third proportional controller, and eighth adder are connected in sequence; The first d / q coordinate system transformation module is connected to the wind turbine rotor voltage compensation calculation module; The differential controller is connected to the wind turbine in the power grid including the wind turbine; The second d / q coordinate system transformation module, phase-locked loop, and twelfth adder are connected in sequence; The inputs of the grid connection point voltage amplitude calculation module of the wind turbine are and ; The inputs of the first adder are and ; The input of the first proportional controller is the output of the first adder, and the proportional coefficient of the first proportional controller is ; The input of the second adder is and the output of the first proportional controller; The input of the third adder is and the output of the second adder; The input of the first PI controller is the output of the third adder; The input of the rotor current reference value calculation module of the wind turbine generator set is the output of the first PI controller , the output of the second integral controller , and ; The input of the fourth adder is the q-axis component of the reference value of the rotor current of the wind turbine output by the rotor current reference value calculation module of the wind turbine and ; The input of the second PI controller is the output of the fourth adder; The input of the fifth adder is the output of the second PI control and ; The / The input of the coordinate system transformation module is the output of the fifth adder and the output of the eleventh adder; The input of the space vector modulation module is the / output of the coordinate system transformation module, and the output of the space vector modulation module is the PWM signal for controlling the wind turbine generator set; The inputs of the sixth adder are and ; The input of the second proportional controller is the output of the sixth adder, and the proportional coefficient of the second proportional controller is ; The input of the seventh adder is the output of the second proportional controller and ; The inputs of the eighth adder are the output of the seventh adder, the output of the third proportional controller, and ; The input of the first integral controller is the output of the eighth adder, and the integral coefficient of the first integral controller is ; The input of the second integral controller is the output of the first integral controller, and the integral coefficient of the second integral controller is ; The input of the ninth adder is and the output of the first integral controller; The input of the multiplier is the output of the ninth adder and ; The input of the third proportional control is the output of the multiplier, and the proportional coefficient of the third proportional control is ; The inputs of the tenth adder are the d-axis component of the reference value of the rotor current of the wind turbine generator set output by the rotor current reference value calculation module of the wind turbine generator set and ; The input of the third PI controller is the output of the tenth adder; The input of the eleventh adder is the output of the third PI controller and ; The input of the first d / q coordinate transformation module is the three-phase currents a, b, c in the power grid containing the wind turbine and the output of the twelfth adder; The inputs of the rotor voltage compensation calculation module of the wind turbine generator set are the output of the first d / q coordinate system transformation module, the output of the differential controller, and ; The input of the differential controller is ; The input of the second d / q coordinate transformation module is the three-phase voltages a, b, c in the power grid containing wind turbines and ; The input of the phase-locked loop is the output of the second d / q coordinate transformation module; The inputs of the twelfth adder are and ; Wherein, is the actual active power output of the wind turbine generator set, is the actual reactive power output of the wind turbine generator set, is the amplitude of the stator voltage of the wind turbine generator set, is the amplitude of the grid connection point voltage of the wind turbine generator set output by the grid connection point voltage amplitude calculation module of the wind turbine generator set, is the rated value of the grid connection point voltage of the wind turbine generator set, is the reactive voltage droop coefficient, is the initial reactive power of the wind turbine generator set, is the actual reactive power output of the wind turbine generator set, is the stator position angle of the wind turbine generator set, is the q-axis component of the rotor voltage compensation of the wind turbine generator set output by the rotor voltage compensation calculation module of the wind turbine generator set, is the rated angular frequency of the virtual synchronous machine, is the grid synchronous angular frequency, is the active power droop coefficient of the wind turbine generator set, is the initial active power of the wind turbine generator set, is the Laplace operator, is the moment of inertia of the virtual synchronous machine, is the damping of the virtual synchronous machine, is the d-axis component of the rotor voltage compensation of the wind turbine generator set output by the rotor voltage compensation calculation module of the wind turbine generator set, is the rotor position angle of the wind turbine generator set, is the stator position angle of the wind turbine generator set, is the position angle of the virtual synchronous machine, is the q-axis component of the actual value of the rotor current of the wind turbine generator set output by the first d / q coordinate system transformation module, is the d-axis component of the actual value of the rotor current of the wind turbine generator set output by the first d / q coordinate system transformation module.

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