Dual-inertia support control method and device for permanent magnet synchronous fan converter

Abstract

The present disclosure relates to the technical field of new energy power generation control, and provides a dual-inertia support control method and device for a permanent magnet synchronous fan converter, which is applied to a permanent magnet synchronous fan grid-connected system, and the permanent magnet synchronous fan is connected to an alternating current grid through a machine-side converter, a DC bus capacitor, a grid-side converter and a transformer in the permanent magnet synchronous fan grid-connected system in sequence. The method comprises the following steps: obtaining a grid frequency of the alternating current grid according to a phase-locked loop; obtaining a fan reference speed according to the grid frequency; generating a first control signal according to the fan reference speed in combination with a first vector control method, and controlling a switching tube of the machine-side converter according to the first control signal; obtaining a DC bus reference voltage according to the grid frequency; generating a second control signal according to the DC bus reference voltage in combination with a second vector control method, and controlling a switching tube of the grid-side converter according to the second control signal.

Description

Technical Field

[0001] This disclosure relates to the field of new energy power generation control technology, specifically to a dual inertia support control method and device for a permanent magnet synchronous wind turbine converter. Background Technology

[0002] Permanent magnet synchronous wind turbines typically achieve grid connection through a two-stage converter. The turbine-side converter is responsible for optimal wind energy capture and tracking, while the grid-side converter maintains DC bus voltage stability and controls grid-connected reactive power. This two-stage power conversion method allows for the decoupling of turbine speed and grid frequency. When grid frequency fluctuates, properly controlling the active power output of the permanent magnet synchronous wind turbine can effectively increase grid inertia, playing a positive supporting role in grid power balance and frequency regulation.

[0003] Related technologies rely on the kinetic energy of the wind turbine rotor to provide grid inertia support. When the energy required for inertia support is large, it can cause significant deviations in wind turbine speed, severely impacting the normal operation of permanent magnet synchronous wind turbines. Furthermore, the inertia support of the turbine-side converter is primarily based on the grid frequency variation rate, requiring differentiation calculations on the grid frequency. In practical engineering, differentiation inevitably amplifies high-frequency noise, severely affecting output performance. Therefore, a low-pass filter is needed to suppress high-frequency noise. However, the introduction of the low-pass filter alters the dynamic characteristics of the inertia support, causing the inertia provided by the wind turbine to differ from the physical inertia. Thus, related technologies suffer from unsatisfactory inertia support performance. Summary of the Invention

[0004] The purpose of this disclosure is to provide a dual inertia support control method and device for a permanent magnet synchronous wind turbine converter, in order to solve the problems in related technologies.

[0005] To achieve the above objectives, this disclosure provides a dual inertia support control method for a permanent magnet synchronous wind turbine converter, applied to a permanent magnet synchronous wind turbine grid-connected system. The permanent magnet synchronous wind turbine is connected to the AC grid sequentially through a machine-side converter, a DC bus capacitor, a grid-side converter, and a transformer in the permanent magnet synchronous wind turbine grid-connected system. The method includes:

[0006] The grid frequency of the AC power grid is obtained based on the phase-locked loop;

[0007] The reference speed of the wind turbine is obtained based on the power grid frequency;

[0008] Based on the wind turbine reference speed, and in conjunction with the first vector control method, a first control signal is generated, and the switching transistors of the turbine-side converter are controlled according to the first control signal;

[0009] The DC bus reference voltage is obtained based on the power grid frequency.

[0010] Based on the DC bus reference voltage and combined with the second vector control method, a second control signal is generated, and the switching transistors of the grid-side converter are controlled according to the second control signal.

[0011] Optionally, the formula for calculating the reference speed of the fan is:

[0012]

[0013] Where, ω ref ω is the reference speed of the fan. MPPT To achieve the maximum wind energy capture, f g Let f0 be the rated frequency of the AC power grid, and Δω be the frequency of the power grid. max Δf is the maximum permissible speed deviation of the fan rotor. max This represents the maximum frequency deviation allowed under normal grid frequency conditions.

[0014] Optionally, the formula for calculating the DC bus reference voltage is:

[0015]

[0016] Among them, v dcref The reference voltage for the DC bus is v. dc0 f is the rated voltage of the DC bus. g f0 is the rated frequency of the AC power grid, and Δv is the frequency of the power grid. dcmax Δf is the maximum allowable voltage deviation of the DC bus. max This represents the maximum frequency deviation allowed under normal grid frequency conditions.

[0017] Optionally, generating the first control signal based on the wind turbine reference speed and in conjunction with the first vector control method includes:

[0018] Obtain the three-phase current i of the permanent magnet synchronous fan abc Phase information and actual rotational speed;

[0019] The difference between the reference speed and the actual speed of the fan is used for proportional-integral control to obtain the q-axis reference current;

[0020] Based on the phase information, the three-phase current i abc Transforming from a three-phase stationary coordinate system to a two-phase rotating coordinate system, we obtain the d-axis current component i. d1 and q-axis current component i q1 ;

[0021] The q-axis reference current and the q-axis current component i q1The difference is used for proportional-integral control to obtain the q-axis voltage value u. q1 ;

[0022] Set the d-axis reference current to 0 and set the d-axis reference current and the d-axis current component i d1 The difference is used for proportional-integral control to obtain the d-axis voltage value u. d1 ;

[0023] Based on the phase information, the d-axis voltage value u d1 and the q-axis voltage value u q1 Transforming from a two-phase rotating coordinate system to a two-phase stationary coordinate system, we obtain the α-axis voltage value u. α1 and β-axis voltage value u β1 ;

[0024] According to the α-axis voltage value u α1 and β-axis voltage value u β1 The first control signal is generated by combining the SVPWM modulation algorithm.

[0025] Optionally, obtaining the grid frequency of the AC power grid based on the phase-locked loop includes:

[0026] Obtain the three-phase voltage v of the AC power grid a v b and v c ;

[0027] The three-phase voltage v a v b and v c Transforming from a three-phase stationary coordinate system to a two-phase rotating coordinate system, we obtain the d-axis voltage component v. d and q-axis voltage component v q ;

[0028] For the q-axis voltage component v q Proportional-integral control is performed, and its steady-state value is kept at zero. The proportional-integral control is then superimposed with the rated frequency of the AC power grid to obtain the power grid frequency.

[0029] By performing integral calculations and radian conversion on the power grid frequency, the angle information required to transform the three-phase stationary coordinate system into the two-phase rotating coordinate system is obtained.

[0030] Optionally, generating the second control signal based on the DC bus reference voltage and in conjunction with the second vector control method includes:

[0031] Obtain the DC bus voltage value v dc Reactive power reference value Q ref The three-phase current i of the permanent magnet synchronous fan abc ;

[0032] The DC bus reference voltage and the DC bus voltage value v dc The difference is used for proportional-integral control to obtain the d-axis reference current i. dref ;

[0033] According to the reactive power reference value Q ref and d-axis voltage component v d The q-axis reference current i is obtained. qref ;

[0034] Based on the angle information, the three-phase current i abc Transforming from a three-phase stationary coordinate system to a two-phase rotating coordinate system, we obtain the d-axis current component i. d2 and q-axis current component i q2 ;

[0035] The d-axis reference current i dref and the d-axis current component i d2 The difference is used for proportional-integral control, and compared with the d-axis voltage component v. d By superimposing the values, we obtain the first voltage value u along the d-axis. d2 ;

[0036] The q-axis reference current i qref and the q-axis current component i q2 The difference is used for proportional-integral control, and is compared with the q-axis voltage component v. q By superimposing the values, we obtain the second voltage value u along the q-axis. q2 ;

[0037] Based on the angle information, the first voltage value u of the d-axis is... d2 and the second voltage value u of the q-axis q2 Transforming from a two-phase rotating coordinate system to a two-phase stationary coordinate system, we obtain the α-axis voltage value u. α2 and β-axis voltage value u β2 ;

[0038] According to the α-axis voltage value u α2 and β-axis voltage value u β2 The second control signal is generated by combining the SVPWM modulation algorithm.

[0039] Optionally, the q-axis reference current i qref The formula for calculation is:

[0040]

[0041] Among them, i qref Q is the q-axis reference current. ref v is the reference value for reactive power. d The d-axis voltage component is the voltage component.

[0042] According to a second aspect of the present disclosure, a dual inertia support control device for a permanent magnet synchronous wind turbine converter is also provided, applied to a permanent magnet synchronous wind turbine grid-connected system. The permanent magnet synchronous wind turbine is connected to the AC power grid sequentially through a machine-side converter, a DC bus capacitor, a grid-side converter, and a transformer in the permanent magnet synchronous wind turbine grid-connected system. The device includes:

[0043] A power grid frequency acquisition module is used to acquire the power grid frequency of the AC power grid based on a phase-locked loop;

[0044] The reference speed acquisition module is used to obtain the wind turbine reference speed based on the power grid frequency;

[0045] The first control module is used to generate a first control signal based on the wind turbine reference speed and in conjunction with a first vector control method, and to control the switching transistors of the turbine-side converter based on the first control signal.

[0046] A reference voltage acquisition module is used to obtain a DC bus reference voltage based on the power grid frequency;

[0047] The second control module is used to generate a second control signal based on the DC bus reference voltage and in conjunction with a second vector control method, and to control the switching transistors of the grid-side converter based on the second control signal.

[0048] According to a third aspect of the present disclosure, a non-transitory computer-readable storage medium is provided, on which a computer program is stored, which, when executed by a processor, implements the steps of the dual inertia support control method for permanent magnet synchronous wind turbine converters provided in the first aspect of the present disclosure.

[0049] According to a fourth aspect of the present disclosure, an electronic device is provided, comprising:

[0050] A memory on which computer programs are stored;

[0051] A processor is configured to execute the computer program in the memory to implement the steps of the dual inertia support control method for permanent magnet synchronous wind turbine converters provided in the first aspect of this disclosure.

[0052] The above technical solution utilizes a phase-locked loop (PLL) to obtain the grid frequency. Based on the grid frequency, the wind turbine reference speed is obtained, and a first control signal is generated using a first vector control method. This first control signal controls the switching transistors of the turbine-side converter to track and perform closed-loop control of the wind turbine speed. Furthermore, based on the grid frequency, the DC bus reference voltage is obtained. Based on the DC bus reference voltage, a second control signal is generated using a second vector control method. This second control signal controls the switching transistors of the grid-side converter to adjust the DC bus voltage and reactive power. This allows for the simultaneous use of the kinetic energy of the wind turbine rotor and the electrical energy of the DC bus capacitor to achieve dual inertia support, improving the effect of permanent magnet synchronous wind turbines on grid inertia support.

[0053] Other features and advantages of this disclosure will be described in detail in the following detailed description section. Attached Figure Description

[0054] The accompanying drawings are provided to further illustrate the present disclosure and form part of the specification. They are used together with the following detailed description to explain the present disclosure, but do not constitute a limitation thereof. In the drawings:

[0055] Figure 1 This is a schematic diagram of a permanent magnet synchronous wind turbine grid-connected system according to an exemplary embodiment;

[0056] Figure 2 This is a flowchart illustrating a dual inertia support control method for a permanent magnet synchronous wind turbine converter according to an exemplary embodiment;

[0057] Figure 3 This is illustrated according to an exemplary embodiment. Figure 2 Flowchart of the sub-steps in step S1;

[0058] Figure 4 This is a block diagram of a phase-locked loop control according to an exemplary embodiment;

[0059] Figure 5 This is illustrated according to an exemplary embodiment. Figure 2 Flowchart of the sub-steps in step S3;

[0060] Figure 6 This is a machine-side converter control block diagram illustrated according to an exemplary embodiment;

[0061] Figure 7 This is illustrated according to an exemplary embodiment. Figure 2 Flowchart of the sub-steps in step S5;

[0062] Figure 8 This is a grid-side converter control block diagram illustrated according to an exemplary embodiment;

[0063] Figure 9 This is a block diagram of a dual inertia support control device for a permanent magnet synchronous wind turbine converter, according to an exemplary embodiment.

[0064] Figure 10 This is a block diagram illustrating an electronic device according to an exemplary embodiment.

[0065] Explanation of reference numerals in the attached figures

[0066] 110 - Permanent magnet synchronous wind turbine; 120 - Machine-side converter; 130 - DC bus capacitor; 140 - Grid-side converter; 150 - Transformer; 160 - AC power grid; 300 - Dual inertia support control device for permanent magnet synchronous wind turbine converter; 301 - Power grid frequency acquisition module; 302 - Reference speed acquisition module; 303 - First control module; 304 - Reference voltage acquisition module; 305 - Second control module; 700 - Electronic equipment; 701 - Processor; 702 - Memory; 703 - Multimedia component; 704 - I / O interface; 705 - Communication component. Detailed Implementation

[0067] The specific embodiments of this disclosure will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit this disclosure.

[0068] In the following description, the words "first" and "second" are used only to distinguish the purpose of the description and should not be interpreted as indicating or implying relative importance or order.

[0069] like Figure 1 As shown, the permanent magnet synchronous wind turbine grid-connected system includes a machine-side converter 120, a DC bus capacitor 130, a grid-side converter 140, and a transformer 150. The DC bus capacitor 130 is connected to the machine-side converter 120 and the grid-side converter 140 via a DC bus. The permanent magnet synchronous wind turbine 110 is connected to the AC power grid 160 sequentially through the machine-side converter 120, the DC bus capacitor 130, the grid-side converter 140, and the transformer 150 in the permanent magnet synchronous wind turbine grid-connected system.

[0070] Based on the above-mentioned permanent magnet synchronous wind turbine grid-connected system, the following is a possible implementation of the dual inertia support control method for permanent magnet synchronous wind turbine converters. The dual inertia support control method for permanent magnet synchronous wind turbine converters provided in this disclosure can be applied to controllers.

[0071] Please see Figure 2 , Figure 2 This is a flowchart illustrating a dual inertia support control method for a permanent magnet synchronous wind turbine converter according to an exemplary embodiment. The dual inertia support control method for a permanent magnet synchronous wind turbine converter may include the following steps:

[0072] Step S1: Obtain the grid frequency of AC grid 160 based on the phase-locked loop.

[0073] Step S2: Obtain the reference speed of the wind turbine based on the grid frequency.

[0074] Step S3: Based on the wind turbine reference speed and combined with the first vector control method, generate a first control signal, and control the switching transistor of the machine-side converter 120 according to the first control signal.

[0075] The first control signal can be the drive signal of the switching transistor of the machine-side converter 120.

[0076] Step S4: Obtain the DC bus reference voltage based on the grid frequency.

[0077] Step S5: Based on the DC bus reference voltage and combined with the second vector control method, a second control signal is generated, and the switching transistors of the grid-side converter 140 are controlled according to the second control signal.

[0078] The second control signal can be the drive signal of the switching transistor of the grid-side converter 140.

[0079] The first and second control signals can be high-frequency square wave signals. When the signal is high, the upper transistor of the corresponding bridge arm of the converter is turned on and the lower transistor is turned off. When the signal is low, the upper transistor of the corresponding bridge arm of the converter is turned off and the lower transistor is turned on.

[0080] The grid frequency is obtained using a phase-locked loop (PLL). Based on the grid frequency, the wind turbine reference speed is obtained, and a first control signal is generated using a first vector control method. The switching transistors of the machine-side converter 120 are controlled according to the first control signal to track and control the wind turbine speed in a closed loop. The DC bus reference voltage is obtained based on the grid frequency. Based on the DC bus reference voltage, a second control signal is generated using a second vector control method. The switching transistors of the grid-side converter 140 are controlled according to the second control signal to adjust the DC bus voltage and reactive power. This allows for the simultaneous use of the kinetic energy of the wind turbine rotor and the electrical energy of the DC bus capacitor 130 to achieve dual inertia support, improving the effect of the permanent magnet synchronous wind turbine 110 on grid inertia support.

[0081] It should be noted that steps S2 and S3 can be executed before steps S4 and S5, or after steps S4 and S5. Steps S2 and S3 can also be executed simultaneously with steps S4 and S5. This embodiment does not impose any limitations on these steps.

[0082] In one possible implementation, please refer to Figure 3 and Figure 4Obtaining the grid frequency of the AC power grid using a phase-locked loop can include the following steps:

[0083] Step S11: Obtain the three-phase voltage v of AC power grid 160. a v b and v c .

[0084] Three-phase voltage V a v b and v c This can be obtained through a voltage sensor.

[0085] Step S12, convert the three-phase voltage v a v b and v c Transforming from a three-phase stationary coordinate system to a two-phase rotating coordinate system, we obtain the d-axis voltage component v. d and q-axis voltage component v q .

[0086] The three-phase stationary coordinate system is the abc coordinate system, and the two-phase rotating coordinate system can be the dq coordinate system. Their correspondence is as follows:

[0087]

[0088] θ1 is the angle information in step S14.

[0089] Step S13, for the q-axis voltage component v q Proportional-integral control is performed, and its steady-state value is kept at zero. The frequency of the grid is obtained by superimposing the proportional-integral control with the rated frequency of the AC grid.

[0090] The rated frequency of an AC power grid can be 50Hz.

[0091] Step S14: Integrate the power grid frequency and convert it to radians to obtain the angle information required to transform the three-phase stationary coordinate system to the two-phase rotating coordinate system.

[0092] In one possible implementation, the formula for calculating the reference speed of the wind turbine is:

[0093]

[0094] Where, ω ref ω is the reference speed of the fan. MPPT To achieve the maximum wind energy capture, f g Here, f0 is the rated frequency of the AC power grid, typically 50Hz, and Δω is the frequency of the mains power grid. max Δf is the maximum permissible speed deviation of the fan rotor. maxThis is the maximum frequency deviation allowed under normal grid frequency conditions, typically 0.2Hz.

[0095] Based on the relationship established by the above formula, the reference speed of the wind turbine depends not only on the maximum power point (MPPT) but also on the grid frequency. Assuming the real-time speed of the wind turbine tracks the reference speed well, the inertial support H1 provided by the wind turbine can be calculated as follows:

[0096]

[0097] Where J is the moment of inertia of the fan rotor, VA rated The rated power level of the power grid and the equivalent inertia time constant H1 are in seconds.

[0098] In one possible implementation, a first control signal is generated based on the wind turbine reference speed and in conjunction with a first vector control method. (See [link to relevant documentation]). Figure 5 and Figure 6 This may include the following steps:

[0099] Step S31: Obtain the three-phase current i of the permanent magnet synchronous fan 110. abc Phase information and actual rotational speed.

[0100] The phase information and actual speed of the permanent magnet synchronous fan 110 can be obtained through a speed and phase detection device. Three-phase current i abc It can be the stator current of a permanent magnet synchronous fan, or the three-phase current i. abc This can be obtained through a current sensor.

[0101] Step S32: The difference between the fan reference speed and the actual speed is subjected to proportional-integral control to obtain the q-axis reference current.

[0102] Step S33: Based on the phase information, the three-phase current i abc Transforming from a three-phase stationary coordinate system to a two-phase rotating coordinate system, we obtain the d-axis current component i. d1 and q-axis current component i q1 .

[0103] Three-phase current i abc It can be seen as i a i b and i c A three-phase stationary coordinate system is the abc coordinate system, while a two-phase rotating coordinate system can be the dq coordinate system. Their correspondence is as follows:

[0104]

[0105] θ2 represents phase information.

[0106] Step S34, combine the q-axis reference current and the q-axis current component iq1 The difference is used for proportional-integral control to obtain the q-axis voltage value u. q1 .

[0107] Step S35: Set the d-axis reference current to 0, and set the d-axis reference current and d-axis current component i d1 The difference is used for proportional-integral control to obtain the d-axis voltage value u. d1 .

[0108] Step S36: Based on the phase information, the d-axis voltage value u d1 and q-axis voltage value u q1 Transforming from a two-phase rotating coordinate system to a two-phase stationary coordinate system, we obtain the α-axis voltage value u. α1 and β-axis voltage value u β1 .

[0109] A two-phase rotating coordinate system can be a dq coordinate system, and a two-phase stationary coordinate system can be an αβ coordinate system. Their correspondence is as follows:

[0110]

[0111] θ2 represents phase information.

[0112] Step S37, based on the α-axis voltage value u α1 and β-axis voltage value u β1 The first control signal is generated by combining the SVPWM modulation algorithm.

[0113] In one possible implementation, the DC bus reference voltage is calculated as follows:

[0114]

[0115] Among them, v dcref The DC bus reference voltage, v dc0 f is the rated voltage of the DC bus. g Here, f0 is the rated frequency of the AC power grid, and Δv is the frequency of the power grid. dcmax The maximum allowable voltage deviation of the DC bus, typically V. dc0 Within the range of 10% to 20%, the specific value needs to take into account the overmodulation constraint of the grid-side converter 140, Δf max This represents the maximum frequency deviation allowed under normal grid frequency conditions.

[0116] The relationship established by the above equation establishes a linear connection between the converter DC bus voltage and the grid frequency. Assuming that the grid-side converter 140 achieves DC bus voltage tracking, the inertia support H2 provided by the DC bus capacitor 130 can be calculated as follows:

[0117]

[0118] Where C dc The capacitance value of the DC bus, VA rated The rated power level of the power grid and the equivalent inertia time constant H2 are in seconds. The total inertia support that the wind turbine converter can provide is the sum of H1 and H2.

[0119] In one possible implementation, a second control signal is generated based on the DC bus reference voltage and in conjunction with a second vector control method. (See [link to relevant documentation]). Figure 7 and Figure 8 This may include the following steps:

[0120] Step S51, obtain the DC bus voltage value v dc Reactive power reference value Q ref The three-phase current i of the permanent magnet synchronous fan abc .

[0121] DC bus voltage value v dc This can be obtained through a voltage sensor. Three-phase current i abc It can be the stator current of a permanent magnet synchronous fan, or the three-phase current i. abc This can be obtained through a current sensor.

[0122] Step S52, the DC bus reference voltage and the DC bus voltage value v dc The difference is used for proportional-integral control to obtain the d-axis reference current i. dref .

[0123] Step S53, based on the reactive power reference value Q ref and d-axis voltage component v d The q-axis reference current i is obtained. qref .

[0124] q-axis reference current i qref The formula for calculation is:

[0125]

[0126] Among them, i qref Q is the q-axis reference current. ref This is the reactive power reference value, v d This represents the d-axis voltage component.

[0127] Step S54: Based on the angle information, the three-phase current i abc Transforming from a three-phase stationary coordinate system to a two-phase rotating coordinate system, we obtain the d-axis current component i. d2 and q-axis current component i q2 .

[0128]

[0129] θ1 represents angle information.

[0130] Step S55, set the d-axis reference current i dref and d-axis current component i d2 The difference is used for proportional-integral control, and compared with the d-axis voltage component v. d By superimposing the values, we obtain the first voltage value u along the d-axis. d2 .

[0131] Step S56, set the q-axis reference current i qref and q-axis current component i q2 The difference is used for proportional-integral control, and is compared with the q-axis voltage component v. q By superimposing the values, we obtain the second voltage value u along the q-axis. q2 .

[0132] Step S57: Based on the angle information, the first voltage value u along the d-axis is... d2 and the second voltage value u on the q-axis q2 Transforming from a two-phase rotating coordinate system to a two-phase stationary coordinate system, we obtain the α-axis voltage value u. α2 and β-axis voltage value u β2 .

[0133]

[0134] θ1 represents angle information.

[0135] Step S58, based on the α-axis voltage value u α2 and β-axis voltage value u β2 The second control signal is generated by combining the SVPWM modulation algorithm.

[0136] To implement the above-described method embodiments, this disclosure provides a dual inertia support control device 300 for a permanent magnet synchronous wind turbine converter. Please refer to [link to relevant documentation]. Figure 9 The device includes a power grid frequency acquisition module 301, a reference speed acquisition module 302, a first control module 303, a reference voltage acquisition module 304, and a second control module 305.

[0137] The power grid frequency acquisition module 301 is used to acquire the power grid frequency of the AC power grid based on the phase-locked loop;

[0138] The reference speed acquisition module 302 is used to obtain the wind turbine reference speed based on the power grid frequency;

[0139] The first control module 303 is used to generate a first control signal based on the wind turbine reference speed and in conjunction with a first vector control method, and to control the switching transistors of the machine-side converter based on the first control signal;

[0140] The reference voltage acquisition module 304 is used to obtain the DC bus reference voltage based on the grid frequency;

[0141] The second control module 305 is used to generate a second control signal based on the DC bus reference voltage and in conjunction with the second vector control method, and to control the switching transistors of the grid-side converter according to the second control signal.

[0142] Optionally, the formula for calculating the reference speed of the fan is:

[0143]

[0144] Where, ω ref ω is the reference speed of the fan. MPPT To achieve the maximum wind energy capture, f g f0 is the rated frequency of the AC power grid, and Δω is the frequency of the power grid. max Δf is the maximum permissible speed deviation of the fan rotor. max This represents the maximum frequency deviation allowed under normal grid frequency conditions.

[0145] Optionally, the formula for calculating the DC bus reference voltage is:

[0146]

[0147] Among them, v dcref The DC bus reference voltage, v dc0 f is the rated voltage of the DC bus. g Here, f0 is the rated frequency of the AC power grid, and Δv is the frequency of the power grid. dcmax Δf is the maximum allowable voltage deviation of the DC bus. max This represents the maximum frequency deviation allowed under normal grid frequency conditions.

[0148] Optionally, the first control module 303 is specifically used for:

[0149] Obtain the three-phase current i of the permanent magnet synchronous fan 110 abc Phase information and actual rotational speed;

[0150] The difference between the fan's reference speed and actual speed is used for proportional-integral control to obtain the q-axis reference current;

[0151] Based on the phase information, the three-phase current i abc Transforming from a three-phase stationary coordinate system to a two-phase rotating coordinate system, we obtain the d-axis current component i. d1 and q-axis current component i q1 ;

[0152] The q-axis reference current and the q-axis current component i q1The difference is used for proportional-integral control to obtain the q-axis voltage value u. q1 ;

[0153] Set the d-axis reference current to 0 and set the d-axis reference current and d-axis current component i d1 The difference is used for proportional-integral control to obtain the d-axis voltage value u. d1 ;

[0154] Based on the phase information, the d-axis voltage value u d1 and q-axis voltage value u q1 Transforming from a two-phase rotating coordinate system to a two-phase stationary coordinate system, we obtain the α-axis voltage value u. α1 and β-axis voltage value u β1 ;

[0155] Based on the α-axis voltage value u α1 and β-axis voltage value u β1 The first control signal is generated by combining the SVPWM modulation algorithm.

[0156] Optionally, the power grid frequency acquisition module 301 is specifically used for:

[0157] Obtain the three-phase voltage v of the AC power grid a v b and v c ;

[0158] The three-phase voltage v a v b and v c Transforming from a three-phase stationary coordinate system to a two-phase rotating coordinate system, we obtain the d-axis voltage component v. d and q-axis voltage component v q ;

[0159] For the q-axis voltage component v q Proportional-integral control is performed, and its steady-state value is kept at zero. The frequency of the grid is obtained by superimposing the proportional-integral control result with the rated frequency of the AC grid.

[0160] By integrating the power grid frequency and converting it to radians, the angle information required to transform the three-phase stationary coordinate system into the two-phase rotating coordinate system is obtained.

[0161] Optionally, the second control module 305 is specifically used for:

[0162] Obtain the DC bus voltage value v dc Reactive power reference value Q ref The three-phase current i of the permanent magnet synchronous fan abc ;

[0163] The DC bus reference voltage and the DC bus voltage value v dcThe difference is used for proportional-integral control to obtain the d-axis reference current i. dref ;

[0164] According to the reactive power reference value Q ref and d-axis voltage component v d The q-axis reference current i is obtained. qref ;

[0165] Based on the angle information, the three-phase current i abc Transforming from a three-phase stationary coordinate system to a two-phase rotating coordinate system, we obtain the d-axis current component i. d2 and q-axis current component i q2 ;

[0166] The d-axis reference current i dref and d-axis current component i d2 The difference is used for proportional-integral control, and compared with the d-axis voltage component v. d By superimposing the values, we obtain the first voltage value u along the d-axis. d2 ;

[0167] The q-axis reference current i qref and q-axis current component i q2 The difference is used for proportional-integral control, and is compared with the q-axis voltage component v. q By superimposing the values, we obtain the second voltage value u along the q-axis. q2 ;

[0168] Based on the angle information, the first voltage value u along the d-axis d2 and the second voltage value u on the q-axis q2 Transforming from a two-phase rotating coordinate system to a two-phase stationary coordinate system, we obtain the α-axis voltage value u. α2 and β-axis voltage value u β2 ;

[0169] Based on the α-axis voltage value u α2 and β-axis voltage value u β2 The second control signal is generated by combining the SVPWM modulation algorithm.

[0170] Optionally, the q-axis reference current i qref The formula for calculation is:

[0171]

[0172] Among them, i qref Q is the q-axis reference current. ref This is the reactive power reference value, v d This represents the d-axis voltage component.

[0173] Regarding the apparatus in the above embodiments, the specific manner in which each module performs its operation has been described in detail in the embodiments related to the method, and will not be elaborated upon here.

[0174] This disclosure also provides a non-transitory computer-readable storage medium storing a computer program that, when executed by a processor, implements the steps of any of the above-described dual inertia support control methods for permanent magnet synchronous wind turbine converters.

[0175] Figure 10 This is a block diagram illustrating an electronic device according to an exemplary embodiment. Figure 10 As shown, the electronic device 700 may include a processor 701 and a memory 702. The electronic device 700 may also include one or more of a multimedia component 703, an input / output (I / O) interface 704, and a communication component 705.

[0176] The processor 701 controls the overall operation of the electronic device 700 to complete all or part of the steps in the aforementioned dual inertia support control method for permanent magnet synchronous wind turbine converters. The memory 702 stores various types of data to support the operation of the electronic device 700. This data may include, for example, instructions for any application or method operating on the electronic device 700, and application-related data such as contact data, sent and received messages, pictures, audio, video, etc. The memory 702 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 storage, flash memory, magnetic disk, or optical disk. Multimedia component 703 may include a screen and an audio component. The screen may be, for example, a touchscreen, and the audio component is used to output and / or input audio signals. For example, the audio component may include a microphone for receiving external audio signals. The received audio signals may be further stored in memory 702 or transmitted via communication component 705. The audio component also includes at least one speaker for outputting audio signals. I / O interface 704 provides an interface between processor 701 and other interface modules, such as a keyboard, mouse, buttons, etc. These buttons may be virtual or physical buttons. Communication component 705 is used for wired or wireless communication between the electronic device 700 and other devices. Wireless communication, such as Wi-Fi, Bluetooth, Near Field Communication (NFC), 2G, 3G, 4G, NB-IoT, eMTC, or other 5G technologies, or combinations thereof, is not limited here. Therefore, the corresponding communication component 705 may include: a Wi-Fi module, a Bluetooth module, an NFC module, etc.

[0177] In an exemplary embodiment, the electronic device 700 may be implemented by one or more application-specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field programmable gate arrays (FPGAs), controllers, microcontrollers, microprocessors, or other electronic components to execute the aforementioned dual inertia support control method for permanent magnet synchronous wind turbine converters.

[0178] In another exemplary embodiment, a computer-readable storage medium including program instructions is also provided, which, when executed by a processor, implement the steps of the dual inertia support control method for permanent magnet synchronous wind turbine converter described above. For example, the computer-readable storage medium may be the memory 702 including program instructions described above, which may be executed by the processor 701 of the electronic device 700 to complete the dual inertia support control method for permanent magnet synchronous wind turbine converter described above.

[0179] Compared with related technologies, this disclosure has the following advantages:

[0180] First, it provides more inertia support for the power grid, effectively reducing the maximum frequency deviation and maximum frequency change rate of the power grid frequency response.

[0181] Second, the implementation of inertia support in this disclosure does not require obtaining the power grid frequency change rate, thus avoiding differential calculations of the power grid frequency and making the implementation more resistant to high-frequency noise interference.

[0182] Third, this solution is simple to implement and does not require changes to the original control system architecture. As can be seen from the control block diagram, its core idea is to dynamically change the DC bus capacitor voltage and motor speed commands through grid frequency detection. In addition, the dynamic commands of capacitor voltage and motor speed have perfect duality, that is, the mapping relationship between speed and voltage, and between mechanical moment of inertia and capacitance value, makes the mathematical expression of the dynamic commands dual and the physical meaning clear and explicit.

[0183] It should be noted that this disclosure is not only applicable to wind power generation systems, but also to any power generation system with a mechanical prime mover driving a generator and connecting to the grid via AC / DC / AC conversion, such as diesel generator sets, tidal power generator sets, and gas turbine generator sets. Finally, from the perspective of demand-side response, motor loads account for more than half of the total grid load. This disclosure is also applicable to inverter-driven motor loads with relatively low requirements for speed control accuracy, such as air conditioners, fans, and water pumps. By dynamically adjusting the DC bus capacitor voltage and motor speed command of this type of load, the active support function of motor loads for grid frequency can be achieved.

[0184] The preferred embodiments of this disclosure have been described in detail above with reference to the accompanying drawings. However, this disclosure is not limited to the specific details of the above embodiments. Within the scope of the technical concept of this disclosure, various simple modifications can be made to the technical solutions of this disclosure, and these simple modifications all fall within the protection scope of this disclosure.

[0185] It should also be noted that the various specific technical features described in the above embodiments can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, this disclosure will not describe the various possible combinations separately.

[0186] Furthermore, various different embodiments of this disclosure can be combined in any way, as long as they do not violate the spirit of this disclosure, they should also be regarded as the content disclosed in this disclosure.

Claims

1. A dual inertia support control method for a permanent magnet synchronous wind turbine converter, characterized in that, An application to a permanent magnet synchronous wind turbine grid-connected system, wherein the permanent magnet synchronous wind turbine is connected to the AC power grid sequentially through a machine-side converter, a DC bus capacitor, a grid-side converter, and a transformer in the system, the method comprising: The grid frequency of the AC power grid is obtained based on the phase-locked loop; The reference speed of the wind turbine is obtained based on the power grid frequency; Based on the wind turbine reference speed, and in conjunction with the first vector control method, a first control signal is generated, and the switching transistors of the turbine-side converter are controlled according to the first control signal; The DC bus reference voltage is obtained based on the power grid frequency. Based on the DC bus reference voltage and combined with the second vector control method, a second control signal is generated, and the switching transistors of the grid-side converter are controlled according to the second control signal; The step of obtaining the grid frequency of the AC power grid based on the phase-locked loop includes: Obtain the three-phase voltage of the AC power grid v a , v b and v c ; The three-phase voltage v a , v b and v c Transforming from a three-phase stationary coordinate system to a two-phase rotating coordinate system yields... d Axis voltage components v d and q Axis voltage components v q ; Regarding the q Axis voltage components v q Perform proportional-integral control so that the q Axis voltage components v q The steady-state value is zero. After proportional-integral control, it is superimposed with the rated frequency of the AC power grid to obtain the power grid frequency. By performing integral calculations and radian conversion on the power grid frequency, the angle information required to transform the three-phase stationary coordinate system into the two-phase rotating coordinate system is obtained. The step of generating a first control signal based on the wind turbine reference speed and in conjunction with a first vector control method includes: Obtain the three-phase current of the permanent magnet synchronous fan. i abc Phase information and actual speed; the difference between the fan reference speed and the actual speed is subjected to proportional-integral control to obtain... q Shaft reference current; based on the phase information, the three-phase current... i abc Transforming from a three-phase stationary coordinate system to a two-phase rotating coordinate system yields... d Axis current components i d1 and q Axis current components i q1 ; will the q Shaft reference current and the q Axis current components i q1 The difference is used for proportional-integral control to obtain... q shaft voltage value u q1 ;Will d Set the shaft reference current to 0, and... d Shaft reference current and the d Axis current components i d1 The difference is used for proportional-integral control to obtain... d shaft voltage value u d1 Based on the phase information, the... d shaft voltage value u d1 and stated q shaft voltage value u q1 Transforming from a two-phase rotating coordinate system to a two-phase stationary coordinate system yields... α shaft voltage value u α1 and β shaft voltage value u β1 According to the above α shaft voltage value u α1 and β shaft voltage value u β1 Combined with the SVPWM modulation algorithm, the first control signal is generated; The step of generating a second control signal based on the DC bus reference voltage and in conjunction with the second vector control method includes: Obtain DC bus voltage value v dc Reactive power reference value Q ref The three-phase current of the permanent magnet synchronous fan i abc The DC bus reference voltage and the DC bus voltage value v dc The difference is used for proportional-integral control to obtain... d Shaft reference current i dref According to the aforementioned reactive power reference value Q ref and d Axis voltage components v d ,get q Shaft reference current i qref Based on the angle information, the three-phase current is... i abc Transforming from a three-phase stationary coordinate system to a two-phase rotating coordinate system yields... d Axis current components i d2 and q Axis current components i q2 ; will the d Shaft reference current i dref and stated d Axis current components i d2 The difference is controlled proportionally and integrally, and... d Axis voltage components v d By superimposing, we obtain d Shaft first voltage value u d2 ; will the q Shaft reference current i qref and stated q Axis current components i q2 The difference is controlled proportionally and integrally, and... q Axis voltage components v q By superimposing, we obtain q Shaft second voltage value u q2 Based on the angle information, the... d Shaft first voltage value u d2 and stated q Shaft second voltage value u q2 Transforming from a two-phase rotating coordinate system to a two-phase stationary coordinate system yields... α shaft voltage value u α2 and β shaft voltage value u β2 According to the above α shaft voltage value u α2 and β shaft voltage value u β2 The second control signal is generated by combining the SVPWM modulation algorithm.

2. The method according to claim 1, characterized in that, The formula for calculating the reference speed of the fan is: in, ω ref The reference speed of the fan is [missing information]. ω MPPT To achieve the maximum wind energy capture, f g The power grid frequency, f 0 represents the rated frequency of the AC power grid. Δω max This represents the maximum permissible speed deviation of the fan rotor. Δf max This represents the maximum frequency deviation allowed under normal grid frequency conditions.

3. The method according to claim 1, characterized in that, The formula for calculating the DC bus reference voltage is: in, v dcref The DC bus reference voltage is... v dc0 This is the rated voltage of the DC bus. f g The power grid frequency, f 0 is the rated frequency of the AC power grid, Δ v dcmax This represents the maximum permissible voltage deviation of the DC bus. Δf max This represents the maximum frequency deviation allowed under normal grid frequency conditions.

4. The method according to claim 1, characterized in that, The q Shaft reference current i qref The formula for calculation is: in, i qref For the q Shaft reference current, Q ref This is the reference value for reactive power. v d For the d Axis voltage component.

5. A dual inertia support control device for a permanent magnet synchronous wind turbine converter, characterized in that, An application in a permanent magnet synchronous wind turbine grid-connected system, wherein the permanent magnet synchronous wind turbine is connected to the AC power grid sequentially through a machine-side converter, a DC bus capacitor, a grid-side converter, and a transformer in the system, the device comprising: A power grid frequency acquisition module is used to acquire the power grid frequency of the AC power grid based on a phase-locked loop; The reference speed acquisition module is used to obtain the wind turbine reference speed based on the power grid frequency; The first control module is used to generate a first control signal based on the wind turbine reference speed and in conjunction with a first vector control method, and to control the switching transistors of the turbine-side converter based on the first control signal. A reference voltage acquisition module is used to obtain a DC bus reference voltage based on the power grid frequency; The second control module is used to generate a second control signal based on the DC bus reference voltage and in conjunction with a second vector control method, and to control the switching transistors of the grid-side converter based on the second control signal. The power grid frequency acquisition module is specifically used to: acquire the three-phase voltage of the AC power grid. v a , v b and v c The three-phase voltage v a , v b and v c Transforming from a three-phase stationary coordinate system to a two-phase rotating coordinate system yields... d Axis voltage components v d and q Axis voltage components v q ; Regarding the q Axis voltage components v q Perform proportional-integral control so that the q Axis voltage components v q The steady-state value is zero. After proportional-integral control, it is superimposed with the rated frequency of the AC power grid to obtain the power grid frequency. The power grid frequency is then integrated and converted to radians to obtain the angle information required to transform the three-phase stationary coordinate system to the two-phase rotating coordinate system. The first control module is specifically used to: acquire the three-phase current of the permanent magnet synchronous fan. i abc Phase information and actual speed; the difference between the fan reference speed and the actual speed is subjected to proportional-integral control to obtain... q Shaft reference current; based on the phase information, the three-phase current... i abc Transforming from a three-phase stationary coordinate system to a two-phase rotating coordinate system yields... d Axis current components i d1 and q Axis current components i q1 ; will the q Shaft reference current and the q Axis current components i q1 The difference is used for proportional-integral control to obtain... q shaft voltage value u q1 ;Will d Set the shaft reference current to 0, and... d Shaft reference current and the d Axis current components i d1 The difference is used for proportional-integral control to obtain... d shaft voltage value u d1 Based on the phase information, the... d shaft voltage value u d1 and stated q shaft voltage value u q1 Transforming from a two-phase rotating coordinate system to a two-phase stationary coordinate system yields... α shaft voltage value u α1 and β shaft voltage value u β1 According to the above α shaft voltage value u α1 and β shaft voltage value u β1 Combined with the SVPWM modulation algorithm, the first control signal is generated; The second control module is specifically used for: acquiring the DC bus voltage value. v dc Reactive power reference value Q ref The three-phase current of the permanent magnet synchronous fan i abc The DC bus reference voltage and the DC bus voltage value v dc The difference is used for proportional-integral control to obtain... d Shaft reference current i dref According to the aforementioned reactive power reference value Q ref and d Axis voltage components v d ,get q Shaft reference current i qref Based on the angle information, the three-phase current is... i abc Transforming from a three-phase stationary coordinate system to a two-phase rotating coordinate system yields... d Axis current components i d2 and q Axis current components i q2 ; will the d Shaft reference current i dref and stated d Axis current components i d2 The difference is subjected to proportional-integral control, and compared with... d Axis voltage components v d By superimposing, we obtain d Shaft first voltage value u d2 ; will the q Shaft reference current i qref and stated q Axis current components i q2 The difference is controlled proportionally and integrally, and... q Axis voltage components v q By superimposing, we obtain q Shaft second voltage value u q2 Based on the angle information, the... d Shaft first voltage value u d2 and stated q Shaft second voltage value u q2 Transforming from a two-phase rotating coordinate system to a two-phase stationary coordinate system yields... α shaft voltage value u α2 and β shaft voltage value u β2 According to the above α shaft voltage value u α2 and β shaft voltage value u β2 The second control signal is generated by combining the SVPWM modulation algorithm.

6. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that, When executed by a processor, the program implements the steps of the method described in any one of claims 1-4.

7. An electronic device, characterized in that, include: A memory on which computer programs are stored; A processor for executing the computer program in the memory to implement the steps of the method according to any one of claims 1-4.

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