Simplified electromagnetic transient simulation model, method, terminal and medium for doubly-fed wind turbine

Abstract

The present invention discloses a simplified electromagnetic transient simulation model, method, terminal and medium of a doubly-fed wind turbine, the model comprising: a reactive control unit, an active control unit and a simplified equivalent model of a wind turbine interface; the reactive control unit is used to input the equivalent internal potential of the wind turbine into the simplified equivalent model of the wind turbine interface; the active control unit is used to input the active current instruction of the wind turbine into the simplified equivalent model of the wind turbine interface; the simplified equivalent model of the wind turbine interface is used to receive the equivalent internal potential and active current instruction of the wind turbine, and connect the wind power generation system to a controlled current source and power grid. By utilizing the simplified equivalent model of the wind turbine interface, the present invention enables the electromagnetic transient simulation model to be applicable to large-step wind power generation system-level simulation analysis, can accurately simulate the active / reactive characteristics of the wind turbine unit at the AC wiring port, and has the advantages of less calculation and faster simulation speed compared with the detailed electromagnetic transient model and averaged model of the traditional wind turbine.

Description

Technical Field

[0001] The present invention relates to the technical field of power system simulation, and in particular to a simplified electromagnetic transient simulation model, method, terminal and medium for a doubly-fed wind turbine. Background Art

[0002] With the large-scale access of wind power to the power grid, wind power has become the most widely used distributed power source in modern power systems, and at the same time has a great impact on the operation, maintenance, dispatching, control and security of the power grid. In order to analyze the impact of large-scale wind power access on the power system and the interaction mechanism, it is necessary to use numerical electromagnetic transient simulation tools to model and simulate wind power units.

[0003] In traditional power system analysis, wind turbines are generally treated as constant power sources, ignoring the mechanical coupling characteristics of wind turbines. In simulation software represented by Matlab / Simulink, fully detailed construction is generally adopted for the doubly fed wind turbine body, converter, wind energy conversion and other contents, which can accurately simulate various transients and switch ripples inside the motor, that is, the behavior characteristics of the wind turbine can be simulated well. However, the model obtained by this detailed modeling is often more complex, and only uses the single-machine characteristic research of the wind turbine, which must rely on a small step size; when the simulation scale is large and the number of switches in the topology is large, the simulation efficiency will drop sharply, and the simulation time may reach several hours or even days. With the increasing demand for the simulation scale of power systems containing large-scale wind power, this simulation model that relies on a small step size is obviously unable to meet the simulation scale requirements. Therefore, a simplified model is urgently needed to achieve a balance between simulation efficiency and simulation accuracy. Summary of the invention

[0004] The purpose of the present invention is to provide a simplified electromagnetic transient simulation model, method, terminal and medium for a doubly fed wind turbine, so as to solve the problem that the existing electromagnetic transient simulation model of a doubly fed wind turbine is only suitable for small step size modeling and cannot be applied to a larger simulation scale.

[0005] To achieve the above object, the present invention provides a simplified electromagnetic transient simulation model of a doubly-fed wind turbine, comprising:

[0006] Simplified equivalent models of reactive power control unit, active power control unit and wind turbine interface;

[0007] The reactive power control unit is used to input the equivalent internal potential of the wind turbine into the simplified equivalent model of the wind turbine interface;

[0008] The active power control unit is used to input the active power current instruction of the fan into the simplified equivalent model of the fan interface;

[0009] The simplified equivalent model of the wind turbine interface is used to receive the equivalent internal potential of the wind turbine and the active current instruction, and connect the wind power generation system to a controlled current source and connect it to the power grid.

[0010] Further, as a preferred embodiment, in the simplified equivalent model of the wind turbine interface, the instantaneous three-phase grid-connected current of the wind turbine is:

[0011]

[0012]

[0013]

[0014] In the formula, i a 、i b 、i c is the three-phase grid current; I M is the grid current amplitude, is the power factor angle, θ is the grid voltage angle; where, and I M satisfy:

[0015]

[0016]

[0017] Further, as a preferred embodiment, the reactive power control unit includes: a wind farm voltage control model and a reactive power control system model;

[0018] The wind farm voltage control model is used to receive the terminal voltage value and input the output reactive power reference value into the reactive power control system model;

[0019] The reactive power control system model is used to generate an equivalent internal potential of the wind turbine according to a reactive power reference value and an input value of reactive power.

[0020] Further, as a preferred embodiment, the active power control unit includes: a wind power model, a rotor dynamic model, an active power control system model and a pitch angle control system model;

[0021] The wind power model is used to calculate the mechanical power according to the ambient wind speed, and input the value corresponding to the mechanical power into the rotor dynamic model;

[0022] The rotor dynamic model is used to calculate the fan speed according to the mechanical power, and input the value corresponding to the fan speed into the active power control system model; and is also used to input the value corresponding to the turbine speed into the wind power model;

[0023] The active power control system model is used to perform active control on the pitch angle control system model according to the active power and the terminal voltage value;

[0024] The pitch angle control system model is used to input the pitch angle into the wind power model.

[0025] The present invention also provides a simplified electromagnetic transient simulation method for a doubly-fed wind turbine, comprising:

[0026] Input terminal voltage value and reactive power value to the reactive control unit, and input the calculated equivalent internal potential of the wind turbine to the simplified equivalent model of the wind turbine interface;

[0027] Inputting the ambient wind speed, active power value and terminal voltage value into the active power control unit, and inputting the calculated active current command into the simplified equivalent model of the wind turbine interface;

[0028] The simplified equivalent model of the wind turbine interface is used to calculate the instantaneous three-phase grid-connected current, the instantaneous value of the three-phase AC voltage and the grid voltage phase angle of the wind turbine.

[0029] Further, as a preferred embodiment, the calculating of the instantaneous three-phase grid-connected current, the instantaneous value of the three-phase AC voltage and the grid voltage phase angle of the wind turbine using the simplified equivalent model of the wind turbine interface includes:

[0030] Electromagnetic transient simulation calculation is carried out by using the alternating solution method of the grid voltage phase angle and the instantaneous value of the three-phase AC voltage.

[0031] Further, preferably, the alternating solution method of the grid voltage phase angle and the instantaneous value of the three-phase AC voltage includes:

[0032] At the current moment, first calculate the grid voltage phase angle, then calculate the instantaneous value of the three-phase AC voltage; or,

[0033] At the current moment, the instantaneous value of the three-phase AC voltage is calculated first, and then the grid voltage phase angle is calculated.

[0034] Furthermore, as a preference, it also includes compensating for the grid voltage phase angle calculated at the next moment when the simulation step size is greater than a preset threshold.

[0035] The present invention also provides a terminal device, comprising:

[0036] one or more processors;

[0037] A memory, coupled to the processor, for storing one or more programs;

[0038] When the one or more programs are executed by the one or more processors, the one or more processors implement the simplified electromagnetic transient simulation method for a doubly-fed wind turbine as described in any one of the above items.

[0039] The present invention also provides a computer-readable storage medium having a computer program stored thereon, and when the computer program is executed by a processor, the simplified electromagnetic transient simulation method for a doubly-fed wind turbine as described in any one of the above items is implemented.

[0040] Compared with the prior art, the beneficial effects of the present invention are:

[0041] The invention discloses a simplified electromagnetic transient simulation model, method, terminal and medium of a doubly-fed wind turbine. The model comprises: a reactive control unit, an active control unit and a simplified equivalent model of a wind turbine interface; the reactive control unit is used to input an equivalent internal potential of the wind turbine into the simplified equivalent model of the wind turbine interface; the active control unit is used to input an active current instruction of the wind turbine into the simplified equivalent model of the wind turbine interface; the simplified equivalent model of the wind turbine interface is used to receive an equivalent internal potential and an active current instruction of the wind turbine, and connect a wind power generation system to a controlled current source and a power grid.

[0042] The present invention uses the fan interface to simplify the equivalent model and considers the influence of the simulation step on the controlled source result. By compensating the phase angle, the electromagnetic transient simulation model can be applied to the large-step wind power generation system-level simulation analysis, and can accurately simulate the active / reactive characteristics of the fan unit at the AC connection port. Compared with the traditional fan detailed electromagnetic transient model and average model, it has the advantages of less calculation and faster simulation speed. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to more clearly illustrate the technical solution of the present invention, the drawings required for use in the implementation mode will be briefly introduced below. Obviously, the drawings described below are only some implementation modes of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0044] Figure 1 It is a structural schematic diagram of a simplified electromagnetic transient simulation model of a doubly-fed wind turbine provided by a certain embodiment of the present invention;

[0045] Figure 2 It is a schematic diagram of the principle of a control method of a simplified electromagnetic transient simulation model of a doubly-fed wind turbine provided by a certain embodiment of the present invention;

[0046] Figure 3 It is a simplified equivalent model circuit diagram of a fan interface based on current source injection provided by a certain embodiment of the present invention;

[0047] Figure 4 It is a schematic diagram of the principle of the numerical value change process in the simulation calculation process provided by a certain embodiment of the present invention;

[0048] Figure 5It is a schematic flow chart of a simplified electromagnetic transient simulation method for a doubly-fed wind turbine provided by a certain embodiment of the present invention;

[0049] Figure 6 It is a schematic diagram of the structure of a terminal device provided by a certain embodiment of the present invention. DETAILED DESCRIPTION

[0050] The following will be combined with the drawings in the embodiments 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.

[0051] It should be understood that the step numbers used in this document are only for convenience of description and are not intended to limit the order in which the steps are executed.

[0052] It should be understood that the terms used in the present specification are only for the purpose of describing specific embodiments and are not intended to limit the present invention. As used in the present specification and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an" and "the" are intended to include plural forms.

[0053] The terms “include” and “comprising” indicate the presence of described features, integers, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or combinations thereof.

[0054] The term "and / or" means and includes any and all possible combinations of one or more of the associated listed items.

[0055] See also Figure 1 A certain embodiment of the present invention provides a simplified electromagnetic transient simulation model of a doubly-fed wind turbine, comprising:

[0056] Simplified equivalent models of reactive power control unit, active power control unit and wind turbine interface;

[0057] The reactive power control unit is used to input the equivalent internal potential of the wind turbine into the simplified equivalent model of the wind turbine interface;

[0058] The active power control unit is used to input the active power current instruction of the fan into the simplified equivalent model of the fan interface;

[0059] The simplified equivalent model of the wind turbine interface is used to receive the equivalent internal potential of the wind turbine and the active current instruction, and connect the wind power generation system to a controlled current source and connect it to the power grid.

[0060] It should be noted that in recent years, the depletion of fossil energy and environmental pollution have become increasingly serious. As a clean, renewable new energy source, wind energy has been highly valued and vigorously developed worldwide. Wind power generation technology is a technology that uses rotating wind power generation equipment and electrical devices to convert wind energy in nature into electrical energy. The wind power generation system is mainly composed of wind turbines, transmission devices, generators, auxiliary systems, and power conversion systems. Among them, the specific process of energy conversion is reflected in: wind energy drives the blades of the wind turbine to rotate, converting wind energy into mechanical energy; the rotation of the blades transmits mechanical energy to the generator through the transmission device, and the generator converts mechanical energy into electrical energy by cutting magnetic flux lines; the generated electrical energy is sorted into standard electrical energy by the conversion device and sent to the power grid or for local load use. With the continuous development and progress of wind power generation technology and the continuous growth of installed capacity, the variable speed constant frequency double-fed wind power generation system has become the most widely used mainstream solution in the current wind power generation market with its advantages such as flexible control and wide operating wind speed range. However, in the existing power system analysis, the wind turbine is usually equivalent to a constant power source and the mechanical coupling characteristics of the wind turbine are ignored. Then, in the simulation software, the double-fed wind turbine body, converter, wind energy conversion and other contents are constructed in detail to accurately simulate various transients and switch ripples inside the motor, that is, to accurately simulate the behavior characteristics of the wind turbine. However, the model obtained by this detailed modeling is often very complex and can only be applied to small-step and small-scale simulations. However, with the increasing demand for the simulation scale of power systems containing large-scale wind power, this simulation model that relies on small steps is obviously unable to meet the simulation scale requirements. Therefore, the embodiment of the present invention aims at a simplified model to achieve a balance between simulation efficiency and simulation accuracy. Among them, the simplified model needs to be able to reflect the active and reactive transient characteristics of the wind turbine unit port, as well as the mechanical characteristics of the wind turbine, and the high-frequency switch ripple characteristics can be simplified. For occasions where refined simulation is required, a fully detailed model is selected, and for system-level analysis, a simplified equivalent model can be selected to achieve a balance between simulation accuracy and simulation efficiency.

[0061] Specifically, this embodiment mainly focuses on the simplified electromagnetic transient model of the doubly-fed wind turbine generator with active / reactive characteristics of the wind turbine unit at the AC connection port. By injecting the wind power generation system into the grid interface as a controlled current source, the influence of the simulation step size on the injected current value is considered. The structure of the electromagnetic transient simulation model of the doubly-fed wind power generation system is as follows: Figure 1As shown in the figure, the model ignores the control of the grid-side converter and mainly includes three parts: reactive power control, active power control and simplified equivalent model of wind turbine interface. Among them, the reactive power control unit is used to input the equivalent internal potential of the wind turbine into the simplified equivalent model of the wind turbine interface; the active power control unit is used to input the active current command of the wind turbine into the simplified equivalent model of the wind turbine interface; the simplified equivalent model of the wind turbine interface is used to receive the equivalent internal potential and active current command of the wind turbine, and connect the wind power generation system to the grid as a controlled current source.

[0062] See also Figure 2 In a specific embodiment, the reactive power control unit includes: a wind farm voltage control model and a reactive power control system model; the active power control unit includes: a wind power model, a rotor dynamic model, an active power control system model and a pitch angle control system model.

[0063] Further, the wind farm voltage control model is used to receive the terminal voltage value and input the output reactive power reference value into the reactive power control system model;

[0064] The reactive power control system model is used to generate the equivalent internal potential of the wind turbine according to the reactive power reference value and the input value of reactive power.

[0065] The wind power model is used to calculate the mechanical power according to the ambient wind speed, and input the value corresponding to the mechanical power into the rotor dynamic model;

[0066] The rotor dynamic model is used to calculate the fan speed according to the mechanical power, and input the value corresponding to the fan speed into the active power control system model; it is also used to input the value corresponding to the turbine speed into the wind power model;

[0067] The active power control system model is used to perform active control on the pitch angle control system model according to the active power and the terminal voltage value;

[0068] The pitch angle control system model is used to input the pitch angle into the wind power model.

[0069] Specifically, Figure 2 The meanings of the various parameters in are as follows: v represents the ambient wind speed, θ r represents the pitch angle, ω r represents the turbine speed, ω g Indicates fan speed, P m Indicates mechanical power, P g Indicates active power, Q g Reactive power, U t Indicates terminal voltage, Q cmd Indicates reactive power reference value, I g Indicates the grid-connected current. Finally, the final output of the simplified reactive power control unit is E” qcmd, represents the equivalent internal potential of the fan, and the final output of the reactive power control unit is I pcmd , indicating the fan active current command.

[0070] It should be noted that according to Figure 2 The control principle of the simplified electromagnetic transient simulation model of the doubly-fed wind turbine provided in the embodiment of the present invention only protects the interface logic between the above-mentioned different control modules. Since the internal implementation logic of the control modules of wind turbines from different manufacturers and different models are different, the specific implementation method inside each controller is not protected here.

[0071] Furthermore, in order to help understand the working principle of the simplified equivalent model of the fan interface, in a specific embodiment, a simplified equivalent model circuit diagram of the fan interface based on current source injection is also provided. Figure 3 As shown, E” qcmd After the first-order inertia link, divided by the equivalent reactance X" of the fan, the reactive current component reference value i is obtained. q , where the first-order inertia link is used to simulate the delay effect of the control system. pcmd After the first-order inertia link and the low-voltage power logic link, the active current component reference value i is obtained. p The low voltage power logic link limits the active current amplitude and change rate of the fan unit according to the drop of the effective value of the terminal voltage. This link is used to suppress the voltage drop during the fault and speed up the voltage recovery speed after the fault is cleared. According to the active and reactive component reference values ​​i of the instantaneous grid current of the fan p ,i q , the instantaneous three-phase grid-connected current of the wind turbine generator is:

[0072]

[0073]

[0074]

[0075] In the formula, i a 、i b 、i c is the three-phase grid current; I M is the grid current amplitude, is the power factor angle, θ is the grid voltage angle, which can be obtained by phase-locking the instantaneous values ​​of the three-phase terminal voltages through a phase-locked loop and adding a delay compensation angle.

[0076] in, and I M satisfy:

[0077]

[0078]

[0079] As an option, when performing electromagnetic transient simulation calculations on the above model, the electrical part and the control part are solved alternately. Among them, there are two typical solution orders: 1) calculate the control part first, then the electrical part; 2) calculate the electrical part first, then the control part. The following takes the first solution order as an example to analyze the effect of simulation step size on Figure 2 The impact of the model shown.

[0080] Specifically, when the system is in steady state, i p ,i q is a fixed value, affecting Figure 3 The main factor of the model is the grid phase angle θ. Among them, Figure 4 It shows the numerical change process during the simulation calculation. It can be seen that the instantaneous value v of the three-phase AC voltage obtained at time t abc , the phase-locked phase is started to solve the grid voltage phase angle in the next time step, that is, the grid voltage phase angle at time t+ΔT is the value θ(t) at time t. i calculated using θ(t) k (t+ΔT)(k=a,b,c) has an error with the true value. It should be noted that when the simulation step size is less than or equal to the preset threshold (smaller), the error can be ignored. However, when the simulation step size is greater than the preset threshold (larger), the output current i that is theoretically intended to be controlled will be p ,i q There is a big difference between the value and the actual calculated and measured value, mainly due to the difference in phase angle, but the modulus value is still the same. Therefore, in order to eliminate the delay caused by the calculation sequence, the controlled source calculation part needs to be compensated. Figure 4 It can be seen that θ(t) lags behind v abc (t+ΔT) is a simulation step, so the θ1 calculated by the PLL can be compensated with an advance angle θ C ,Right now:

[0081] θ=θ1+θ C

[0082] θ C =ωΔT;

[0083] In the formula, ω is the grid angular frequency. After introducing delay compensation, it can be guaranteed that i p ,i q The reference value is consistent with the actual calculated and measured value in terms of phase angle and amplitude.

[0084] In summary, the simplified electromagnetic transient simulation model of the doubly-fed wind turbine provided by the embodiment of the present invention takes into account the influence of the simulation step on the controlled source result by simplifying the equivalent model using the wind turbine interface. By compensating the phase angle, the electromagnetic transient simulation model can be applied to the large-step wind power generation system-level simulation analysis, and can accurately simulate the active / reactive characteristics of the wind turbine unit at the AC connection port. Compared with the detailed electromagnetic transient model and averaged model of the traditional wind turbine, it has the advantages of less calculation and faster simulation speed.

[0085] See also Figure 5 Based on the simplified electromagnetic transient simulation model of the doubly-fed wind turbine provided in the above embodiment, a certain embodiment of the present invention further provides a simplified electromagnetic transient simulation method for a doubly-fed wind turbine. Figure 5 As shown, the simplified electromagnetic transient simulation method for a doubly-fed wind turbine includes steps S10 to S30. The specific steps are as follows:

[0086] S10, input terminal voltage value and reactive power value to the reactive control unit, and input the calculated equivalent internal potential of the wind turbine to the simplified equivalent model of the wind turbine interface.

[0087] It should be noted that the reactive control unit includes: a wind farm voltage control model and a reactive power control system model; wherein the wind farm voltage control model is used to receive the terminal voltage value and input the output reactive power reference value into the reactive power control system model; the reactive power control system model is used to generate the equivalent internal potential of the wind turbine according to the reactive power reference value and the input value of reactive power. The active control unit includes: a wind power model, a rotor dynamic model, an active power control system model and a pitch angle control system model. wherein the wind power model is used to calculate the mechanical power according to the ambient wind speed and input the value corresponding to the mechanical power into the rotor dynamic model; the rotor dynamic model is used to calculate the wind turbine speed according to the mechanical power and input the value corresponding to the wind turbine speed into the active power control system model; it is also used to input the value corresponding to the turbine speed into the wind power model; the active power control system model is used to perform active control on the pitch angle control system model according to the active power and the terminal voltage value; the pitch angle control system model is used to input the pitch angle into the wind power model.

[0088] S20, inputting the ambient wind speed, active power value and terminal voltage value into the active power control unit, and inputting the calculated active current command into the simplified equivalent model of the wind turbine interface;

[0089] Specifically, the instantaneous three-phase grid-connected current of the wind turbine is:

[0090]

[0091]

[0092]

[0093] In the formula, i a 、i b 、i c is the three-phase grid current; I M is the grid current amplitude, is the power factor angle, θ is the grid voltage angle, which can be obtained by phase-locking the instantaneous values ​​of the three-phase terminal voltages through a phase-locked loop and adding a delay compensation angle.

[0094] in, and I M satisfy:

[0095]

[0096]

[0097] S30, using the simplified equivalent model of the wind turbine interface to calculate the instantaneous three-phase grid-connected current, the instantaneous value of the three-phase AC voltage, and the grid voltage phase angle of the wind turbine. Specifically, when executing step S30, the electromagnetic transient simulation calculation is mainly performed by using the alternating solution method of the grid voltage phase angle and the instantaneous value of the three-phase AC voltage, including: first calculating the grid voltage phase angle at the current moment, and then calculating the instantaneous value of the three-phase AC voltage; or first calculating the instantaneous value of the three-phase AC voltage at the current moment, and then calculating the grid voltage phase angle.

[0098] In a specific implementation, when the simulation step is less than or equal to the preset threshold, the error can be ignored. However, when the simulation step is greater than the preset threshold, there will be a large difference between the theoretically desired output current value and the actual calculated and measured value, mainly due to the difference in phase angle, and the modulus value remains the same). In order to eliminate the delay caused by the calculation sequence, the controlled source calculation part needs to be compensated, that is, the grid voltage phase angle calculated at the next moment is compensated.

[0099] It can be understood that the simplified electromagnetic transient simulation method of the doubly-fed wind turbine provided by the embodiment of the present invention takes into account the influence of the simulation step on the controlled source result by simplifying the equivalent model using the wind turbine interface. By compensating the phase angle, the electromagnetic transient simulation model can be applied to the large-step wind power generation system-level simulation analysis, and can accurately simulate the active / reactive characteristics of the wind turbine unit at the AC connection port. Compared with the detailed electromagnetic transient model and averaged model of the traditional wind turbine, it has the advantages of less calculation and faster simulation speed.

[0100] See also Figure 6 , a certain embodiment of the present invention provides a terminal device, including:

[0101] one or more processors;

[0102] A memory, coupled to the processor, for storing one or more programs;

[0103] When the one or more programs are executed by the one or more processors, the one or more processors implement the simplified electromagnetic transient simulation method for a doubly-fed wind turbine as described above.

[0104] The processor is used to control the overall operation of the terminal device to complete all or part of the steps of the simplified electromagnetic transient simulation method for a doubly fed wind turbine. The memory is used to store various types of data to support the operation of the terminal device, and these data may include, for example, instructions for any application or method used to operate on the terminal device, as well as application-related data. The memory can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic memory, flash memory, disk or optical disk.

[0105] In an exemplary embodiment, the terminal device can be implemented by one or more application specific integrated circuits (Application Specific 1n Integrated Circuit, referred to as ASC), digital signal processors (Digital Signal Processor, referred to as DSP), digital signal processing devices (Digital Signal Processing Device, referred to as DSPD), programmable logic devices (Programmable Logic Device, referred to as PLD), field programmable gate arrays (Field Programmable Gate Array, referred to as FPGA), controllers, microcontrollers, microprocessors or other electronic components, and is used to execute the simplified electromagnetic transient simulation method of the doubly fed wind turbine as described in any of the above embodiments, and achieve the same technical effect as the above method.

[0106] In another exemplary embodiment, a computer-readable storage medium including a computer program is also provided, and when the computer program is executed by a processor, the steps of the simplified electromagnetic transient simulation method for a doubly-fed wind turbine as described in any of the above embodiments are implemented. For example, the computer-readable storage medium may be the above-mentioned memory including the computer program, and the above-mentioned computer program may be executed by a processor of a terminal device to complete the simplified electromagnetic transient simulation method for a doubly-fed wind turbine as described in any of the above embodiments, and achieve the same technical effect as the above-mentioned method.

[0107] The above is a preferred embodiment of the present invention. It should be pointed out that a person skilled in the art can make several improvements and modifications without departing from the principle of the present invention. These improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A simplified electromagnetic transient simulation model of a doubly-fed wind turbine, characterized in that: include: Simplified equivalent models of reactive power control unit, active power control unit and wind turbine interface; The reactive power control unit is used to input the equivalent internal potential of the wind turbine into the simplified equivalent model of the wind turbine interface; The active power control unit is used to input the active power current instruction of the fan into the simplified equivalent model of the fan interface; The simplified equivalent model of the wind turbine interface is used to receive the equivalent internal potential of the wind turbine and the active current instruction, and connect the wind power generation system to the power grid as a controlled current source; In the simplified equivalent model of the wind turbine interface, the instantaneous three-phase grid-connected current of the wind turbine is: In the formula, i a 、i b 、i c is the three-phase grid current; I M is the grid current amplitude, is the power factor angle, θ is the grid voltage angle, which is obtained by phase-locking the instantaneous value of the three-phase terminal voltage through a phase-locked loop and adding the delay compensation angle; where, and I M satisfy: In the formula, i p is the active component reference value of the instantaneous grid-connected current of the wind turbine, i q It is the reference value of reactive component of instantaneous grid-connected current of wind turbine; θ satisfies: Where ω is the grid angular frequency, θ1 is the phase angle calculated by the phase-locked loop, and θ C is the delay compensation angle, ΔT is the time step; The reactive power control unit includes: a wind farm voltage control model and a reactive power control system model; The wind farm voltage control model is used to receive the terminal voltage value and input the output reactive power reference value into the reactive power control system model; The reactive power control system model is used to generate an equivalent internal potential of the wind turbine according to a reactive power reference value and an input value of reactive power; The active power control unit includes: a wind power model, a rotor dynamic model, an active power control system model and a pitch angle control system model; The wind power model is used to calculate the mechanical power according to the ambient wind speed, and input the value corresponding to the mechanical power into the rotor dynamic model; The rotor dynamic model is used to calculate the fan speed according to the mechanical power, and input the value corresponding to the fan speed into the active power control system model; and is also used to input the value corresponding to the turbine speed into the wind power model; The active power control system model is used to perform active control on the pitch angle control system model according to the active power and the terminal voltage value; The pitch angle control system model is used to input the pitch angle into the wind power model.

2. A simplified electromagnetic transient simulation method for a doubly-fed wind turbine, characterized in that: include: Input terminal voltage value and reactive power value to the reactive control unit, and input the calculated equivalent internal potential of the wind turbine to the simplified equivalent model of the wind turbine interface; Inputting the ambient wind speed, active power value and terminal voltage value into the active power control unit, and inputting the calculated active current command into the simplified equivalent model of the wind turbine interface; The simplified equivalent model of the wind turbine interface is used to calculate the instantaneous three-phase grid-connected current, the instantaneous value of the three-phase AC voltage and the grid voltage phase angle of the wind turbine; In the simplified equivalent model of the wind turbine interface, the instantaneous three-phase grid-connected current of the wind turbine is: In the formula, i a 、i b 、i c is the three-phase grid current; I M is the grid current amplitude, is the power factor angle, θ is the grid voltage angle, which is obtained by phase-locking the instantaneous value of the three-phase terminal voltage through a phase-locked loop and adding the delay compensation angle; where, and I M satisfy: In the formula, i p is the active component reference value of the instantaneous grid-connected current of the wind turbine, i q It is the reference value of reactive component of instantaneous grid-connected current of wind turbine; θ satisfies: Where ω is the grid angular frequency, θ1 is the phase angle calculated by the phase-locked loop, and θ C is the delay compensation angle, ΔT is the time step; The reactive power control unit includes: a wind farm voltage control model and a reactive power control system model; The wind farm voltage control model is used to receive the terminal voltage value and input the output reactive power reference value into the reactive power control system model; The reactive power control system model is used to generate an equivalent internal potential of the wind turbine according to a reactive power reference value and an input value of reactive power; The active power control unit includes: a wind power model, a rotor dynamic model, an active power control system model and a pitch angle control system model; The wind power model is used to calculate the mechanical power according to the ambient wind speed, and input the value corresponding to the mechanical power into the rotor dynamic model; The rotor dynamic model is used to calculate the fan speed according to the mechanical power, and input the value corresponding to the fan speed into the active power control system model; and is also used to input the value corresponding to the turbine speed into the wind power model; The active power control system model is used to perform active control on the pitch angle control system model according to the active power and the terminal voltage value; The pitch angle control system model is used to input the pitch angle into the wind power model.

3. The simplified electromagnetic transient simulation method for a doubly-fed wind turbine according to claim 2, characterized in that: The method of calculating the instantaneous three-phase grid-connected current, the instantaneous value of the three-phase AC voltage and the grid voltage phase angle of the wind turbine generator by using the simplified equivalent model of the wind turbine interface includes: Electromagnetic transient simulation calculation is carried out by using the alternating solution method of the grid voltage phase angle and the instantaneous value of the three-phase AC voltage.

4. The simplified electromagnetic transient simulation method for a doubly-fed wind turbine according to claim 3 is characterized in that: The alternating solution method for the grid voltage phase angle and the instantaneous value of the three-phase AC voltage includes: At the current moment, first calculate the grid voltage phase angle, then calculate the instantaneous value of the three-phase AC voltage; or, At the current moment, the instantaneous value of the three-phase AC voltage is calculated first, and then the grid voltage phase angle is calculated.

5. The simplified electromagnetic transient simulation method for a doubly-fed wind turbine according to claim 4, characterized in that: Also includes: When the simulation step size is greater than the preset threshold, the grid voltage phase angle calculated at the next moment is compensated.

6. A terminal device, characterized in that: include: one or more processors; A memory, coupled to the processor, for storing one or more programs; When the one or more programs are executed by the one or more processors, the one or more processors implement the simplified electromagnetic transient simulation method for a doubly-fed wind turbine as described in any one of claims 2 to 5.

7. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the simplified electromagnetic transient simulation method for a doubly-fed wind turbine as described in any one of claims 2 to 5 is implemented.

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