A high-multiple speed control method and device for an electromagnetic coupler based on a voltage closed loop

Abstract

The application discloses a high-multiple speed change control method and device of an electromagnetic coupler based on a voltage closed loop and belongs to the technical field of electromagnetic couplers. According to the deviation of a maximum voltage constraint and a voltage instruction amplitude, the method generates a d-axis excitation current given value of the electromagnetic coupler; according to the excitation current given value and a maximum current constraint, a q-axis torque current amplitude limit value under the current constraint is determined; and according to a maximum slip frequency constraint, a q-axis torque current amplitude limit value corresponding to a slip frequency voltage form and a current form constraint is determined, and a q-axis torque current amplitude limit value under the slip frequency constraint is obtained. Then, the amplitude limit values corresponding to the current constraint and the slip frequency constraint are fused, an ultimate q-axis torque current amplitude limit value is output, the q-axis torque current initial given value is limited in amplitude, and the control is completed in combination with the d-axis excitation current given value. The method improves the torque output capacity under the conditions that the voltage, the current and the slip frequency are limited, expands the speed regulation range of a wind turbine generator, and improves the operation stability in a low wind speed area.

Description

Technical Field

[0001] This invention belongs to the field of electromagnetic coupler technology, and in particular relates to a high-speed control method and device for electromagnetic couplers based on voltage closed-loop. Background Technology

[0002] Wind turbine generators are crucial equipment for grid-connected power generation in the renewable energy sector. Existing variable-speed constant-frequency wind turbine generators mainly include doubly-fed asynchronous and permanent magnet direct-drive types. With the continuous expansion of wind power installed capacity, the grid-connected adaptability of wind turbine generators under grid faults, low-voltage disturbances, and wide wind speed operating conditions is receiving increasing attention. Compared to synchronous generators such as thermal and hydropower units, some wind turbine generators still have limitations in their transient overload capacity and support capabilities during grid disturbances, and their operational stability and grid friendliness during fault periods need further improvement.

[0003] To improve the grid support capability of wind turbines, existing technologies have introduced schemes that combine synchronous generators with front-end speed control devices. For example, hydraulic torque-regulating wind turbines can achieve speed matching through hydraulic transmission; new wind turbines based on electromagnetic coupling speed control devices connect the gearbox shaft and the synchronous generator rotor shaft through an electromagnetic coupler, and the electromagnetic torque of the electromagnetic coupler or the relative speed between the two rotors is adjusted by a frequency converter. After the synchronous generator is connected to the grid, it can provide reactive power support through forced excitation when the grid voltage drops, and the electromagnetic coupler can also isolate fault impact torque to a certain extent.

[0004] However, when operating in low wind speed areas, wind turbines based on electromagnetic front-end speed regulation typically require a large front-end speed ratio. The operating range of the electromagnetic coupler is easily affected by boundary conditions such as voltage, current, and slip frequency. As the speed ratio increases, the difficulty of coordinating the unit's torque output, speed range, and stable operating margin increases, which may lead to problems such as insufficient energy harvesting capacity at low wind speeds, decreased torque response capability, or reduced operational stability over a wide speed range. Summary of the Invention

[0005] The purpose of this invention is to provide a voltage-closed-loop electromagnetic coupler high-speed control method and device, which can improve the torque output capability of the electromagnetic coupler under the limited conditions of voltage, current and slip frequency when the wind turbine is operating in the low wind speed area with high-speed control at the front end based on electromagnetic front-end speed regulation, thus widening the speed regulation range of the wind turbine and improving the operating stability in the low wind speed area.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: In a first aspect, this invention provides a voltage-closed-loop-based high-speed control method for electromagnetic couplers, applied to the electromagnetic coupler control of wind turbine generators based on electromagnetic front-end speed regulation under high-speed front-end conditions in low wind speed regions. The method includes: Obtain the maximum voltage constraint, maximum current constraint, and maximum slip frequency constraint of the electromagnetic coupler; Obtain the d-axis voltage command and q-axis voltage command of the electromagnetic coupler in the dq-axis synchronous rotating coordinate system, and generate the voltage command amplitude based on the d-axis voltage command and q-axis voltage command; The d-axis excitation current setpoint of the electromagnetic coupler is generated based on the deviation between the maximum voltage constraint and the voltage command amplitude. Based on the given d-axis excitation current and the maximum current constraint, a q-axis torque current limit value under current constraint is generated. Based on the maximum slip frequency constraint, q-axis torque current limit values ​​under slip frequency voltage form constraint and slip frequency current form constraint are generated. Based on the q-axis torque current limit values ​​under slip frequency voltage form constraint and slip frequency current form constraint, a q-axis torque current limit value under slip frequency constraint is generated. Based on the q-axis torque current limit value under the current constraint and the q-axis torque current limit value under the slip frequency constraint, the final q-axis torque current limit value is generated. The initial setpoint of the q-axis torque current is limited to the final limit value of the q-axis torque current to obtain the limited q-axis torque current setpoint, and the electromagnetic coupler is controlled according to the d-axis excitation current setpoint and the limited q-axis torque current setpoint.

[0007] Furthermore, the high-speed control method for electromagnetic couplers based on voltage closed-loop also includes: Obtain a first electrical angular velocity corresponding to the mechanical rotation speed of the gearbox-side mechanical port of the electromagnetic coupler, and a second electrical angular velocity corresponding to the mechanical rotation speed of the synchronous generator-side mechanical port of the electromagnetic coupler; The slip electrical angular velocity is determined based on the q-axis torque current setpoint and the d-axis excitation current setpoint, wherein the slip electrical angular velocity satisfies:

[0008] in, The rotor time constant, The q-axis torque current setpoint. The given value for the d-axis excitation current; A synchronous electric angular velocity is generated based on the first electric angular velocity, the second electric angular velocity, and the slip electric angular velocity, wherein the synchronous electric angular velocity satisfies:

[0009] in, For synchronous electric angular velocity, The first electric angular velocity, The second electric angular velocity, The slip electrical angular velocity; The flux linkage angle is generated based on the synchronous electric angular velocity, wherein the flux linkage angle satisfies:

[0010] in, The flux linkage angle is mentioned above. Based on the flux linkage angle, the feedback current of the electromagnetic coupler is transformed to obtain the d-axis feedback current and q-axis feedback current in the dq-axis synchronous rotating coordinate system. Based on the flux linkage angle, the d-axis voltage command and q-axis voltage command output by the electromagnetic coupler current controller are transformed to obtain the α-axis voltage command and β-axis voltage command in the αβ-axis two-phase stationary coordinate system input to the modulation module.

[0011] Furthermore, the step of obtaining the d-axis voltage command and q-axis voltage command of the electromagnetic coupler in the dq-axis synchronous rotating coordinate system, and generating the voltage command amplitude based on the d-axis voltage command and the q-axis voltage command includes: The voltage command amplitude is generated based on the following formula:

[0012] in, The voltage command amplitude, This refers to the d-axis voltage command. This refers to the q-axis voltage command.

[0013] Furthermore, the step of generating the d-axis excitation current setpoint of the electromagnetic coupler based on the deviation between the maximum voltage constraint and the voltage command amplitude includes: Using the maximum voltage value in the maximum voltage constraint as the voltage setpoint and the voltage command amplitude as the voltage feedback value, proportional-integral adjustment is performed based on the difference between the voltage setpoint and the voltage feedback value to obtain the excitation current adjustment value; The excitation current adjustment value is limited by using the rated excitation current value as the maximum limit value and the minimum excitation current value as the minimum limit value, so as to obtain the d-axis excitation current setpoint value.

[0014] Furthermore, the step of generating the q-axis torque current limit value under current constraint based on the given d-axis excitation current and the maximum current constraint includes: Based on the maximum current value in the maximum current constraint and the given value of the d-axis excitation current, the q-axis torque current limit value under the current constraint is calculated according to the following formula:

[0015] in, This is the q-axis torque current limit value under the aforementioned current constraint. The maximum current value, The given value for the d-axis excitation current.

[0016] Furthermore, the steps of generating the q-axis torque current limit value under the slip frequency voltage form constraint and the q-axis torque current limit value under the slip frequency current form constraint, based on the maximum slip frequency constraint, include: Based on the maximum voltage value and The ratio generates the slip frequency constraint voltage setpoint, and the slip frequency constraint voltage feedback value is generated based on the absolute value of the d-axis voltage command. Based on the difference between the given value of the slip frequency constraint voltage and the feedback value of the slip frequency constraint voltage, proportional-integral adjustment and limiting processing are performed to obtain the q-axis torque current limiting value under the slip frequency voltage constraint. Based on the given d-axis excitation current and leakage inductance factor, the q-axis torque current limit value under the slip frequency current constraint is calculated using the following formula:

[0017] in, This is the q-axis torque current limit value under the slip frequency current form constraint. The given value for the d-axis excitation current. The leakage sensitivity factor is mentioned above.

[0018] Furthermore, the step of generating the q-axis torque current limit value under the slip frequency constraint, based on the q-axis torque current limit value under the slip frequency voltage constraint and the q-axis torque current limit value under the slip frequency current constraint, includes: The q-axis torque current limit value under the slip frequency constraint is generated by summing the q-axis torque current limit value under the slip frequency voltage form constraint and the q-axis torque current limit value under the slip frequency current form constraint. Wherein, the q-axis torque current limiting value under the slip frequency constraint satisfies:

[0019] in, This is the q-axis torque current limiting value under the slip frequency constraint. This refers to the q-axis torque current limiting value under the slip frequency voltage constraint. The value is the q-axis torque current limit under the slip frequency current form constraint.

[0020] In a second aspect, the present invention provides a voltage-closed-loop electromagnetic coupler high-speed control device, applied to the electromagnetic coupler control of a wind turbine generator based on electromagnetic front-end speed regulation under high-speed front-end conditions in low wind speed areas. The device comprises: The constraint acquisition module is used to acquire the maximum voltage constraint, maximum current constraint, and maximum slip frequency constraint of the electromagnetic coupler. The voltage command amplitude generation module is used to obtain the d-axis voltage command and q-axis voltage command of the electromagnetic coupler in the dq-axis synchronous rotating coordinate system, and generate the voltage command amplitude based on the d-axis voltage command and q-axis voltage command; A first voltage controller is configured to generate a d-axis excitation current setpoint for the electromagnetic coupler based on the deviation between the maximum voltage constraint and the voltage command amplitude. The current constraint processing module is used to generate the q-axis torque current limit value under the current constraint based on the given value of the d-axis excitation current and the maximum current constraint. The slip frequency constraint processing module is used to generate q-axis torque current limit values ​​under slip frequency voltage form constraint and q-axis torque current limit values ​​under slip frequency current form constraint according to the maximum slip frequency constraint, and to generate q-axis torque current limit values ​​under slip frequency constraint according to the q-axis torque current limit values ​​under slip frequency voltage form constraint and q-axis torque current limit values ​​under slip frequency current form constraint. The final limiting generation module is used to generate the final limiting value of q-axis torque current based on the q-axis torque current limiting value under the current constraint and the q-axis torque current limiting value under the slip frequency constraint. The torque current limiting module is used to limit the initial setpoint of the q-axis torque current to within the final limit value of the q-axis torque current, so as to obtain the limited q-axis torque current setpoint. A current controller is used to control the electromagnetic coupler based on the given value of the d-axis excitation current and the given value of the q-axis torque current after limiting.

[0021] In a third aspect, the present invention provides an electronic device including a processor and a memory, the processor being configured to execute a computer program stored in the memory to implement a voltage-closed-loop electromagnetic coupler high-speed control method.

[0022] In a fourth aspect, the present invention provides a computer-readable storage medium storing at least one instruction that, when executed by a processor, implements a voltage-closed-loop-based high-speed control method for electromagnetic couplers.

[0023] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. By acquiring the maximum voltage constraint, maximum current constraint, and maximum slip frequency constraint of the electromagnetic coupler, and generating the voltage command amplitude based on the dq axis voltage command, and then generating the d-axis excitation current setpoint based on the voltage constraint feedback, and simultaneously limiting the q-axis torque current setpoint by combining the maximum current constraint and the maximum slip frequency constraint, the excitation current and torque current of the electromagnetic coupler can be coordinated under the high-speed-multiplication ...

[0024] 2. Based on the d-axis and q-axis voltage commands, a voltage command amplitude is generated. Then, the maximum voltage value is used as the voltage setpoint, and the voltage command amplitude is used as the voltage feedback value for proportional-integral regulation and amplitude limiting. This allows the d-axis excitation current setpoint to be adjusted according to the voltage constraint state. It can automatically adjust the excitation current to meet the voltage constraint without judging whether the electromagnetic coupler is in a low wind speed area or a high-speed conversion condition. It has good engineering feasibility, high DC bus voltage utilization, and can enhance the operational stability under voltage constraints in high-speed conversion conditions.

[0025] 3. By generating a q-axis torque current limit value under current constraints based on the maximum current value and the d-axis excitation current setpoint, and generating a q-axis torque current limit value under slip frequency voltage constraints through a second voltage controller, and generating a q-axis torque current limit value under slip frequency current constraints through a slip frequency constraint calculation stage, and then determining the q-axis torque current limit value under slip frequency constraints based on both, the q-axis torque current can be simultaneously subject to maximum current constraints and maximum slip frequency constraints. Among these, slip frequency current constraints can improve the response speed of the limiting process, while slip frequency voltage constraints can reduce the impact of parameter offset on the limiting value through closed-loop correction, thus balancing the speed of slip frequency constraint processing and parameter robustness. Attached Figure Description

[0026] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings: Figure 1 A flowchart of a high-speed control method for electromagnetic couplers based on voltage closed-loop provided in an embodiment of the present invention; Figure 2 A schematic diagram of the control structure of the high-speed control method for electromagnetic couplers based on voltage closed-loop provided in an embodiment of the present invention; Figure 3 This is a structural block diagram of the electromagnetic coupler high-speed control device based on voltage closed-loop according to an embodiment of the present invention; Figure 4 This is a structural block diagram of an electronic device according to an embodiment of the present invention. Detailed Implementation

[0027] The present invention will now be described in detail with reference to the accompanying drawings and embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other.

[0028] The following detailed description is exemplary and intended to provide further detailed explanation of the invention. Unless otherwise specified, all technical terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains. The terminology used in this invention is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention.

[0029] Example 1 This invention provides a voltage-closed-loop-based electromagnetic coupler high-speed control method, applied to the electromagnetic coupler control of wind turbines based on electromagnetic front-end speed regulation under high-speed front-end conditions in low wind speed regions. Figure 1 As shown, the method includes steps S1 to S6.

[0030] Wind turbines based on electromagnetic front-end speed regulation include an electromagnetic coupler, a gearbox, a synchronous generator, and a frequency converter for controlling the electromagnetic coupler. The two mechanical ports of the electromagnetic coupler are connected to the gearbox shaft and the synchronous generator rotor shaft, respectively. The frequency converter controls the electromagnetic torque of the electromagnetic coupler or the relative speed between the two mechanical ports. Therefore, when a voltage dip fault occurs in the power grid, the synchronous generator in the wind turbine can provide reactive power support to the grid through forced excitation, and the impact torque generated by the synchronous generator during a fault can be isolated by the electromagnetic coupler.

[0031] Specifically, the low-wind-speed front-end high-ratio speed regulation condition refers to the situation where, when a wind turbine based on electromagnetic front-end speed regulation operates in a low-wind-speed region, the speed ratio of the electromagnetic coupler is higher than that under rated operating conditions. The method in this embodiment is applicable to this condition, but it is not necessary to determine whether the electromagnetic coupler is under this condition beforehand during the control process. When the voltage command amplitude is close to the maximum voltage constraint, the d-axis excitation current setpoint can be automatically adjusted through the voltage closed loop, and the q-axis torque current setpoint can be adjusted in combination with the maximum current constraint and the maximum slip frequency constraint to ensure that the electromagnetic coupler meets multiple constraint conditions.

[0032] In one embodiment, the high-speed control method for electromagnetic couplers based on voltage closed-loop provided by the present invention further includes: Obtain the first electrical angular velocity corresponding to the mechanical rotation speed of the gearbox-side mechanical port of the electromagnetic coupler, and the second electrical angular velocity corresponding to the mechanical rotation speed of the synchronous generator-side mechanical port of the electromagnetic coupler; The synchronous electric angular velocity is generated based on the first electric angular velocity, the second electric angular velocity, and the slip electric angular velocity; The flux linkage angle is generated based on the synchronous electric angular velocity; Based on the flux linkage angle, the feedback current of the electromagnetic coupler is transformed into coordinates to obtain the d-axis feedback current and q-axis feedback current in the synchronous rotating coordinate system of the dq axis. Based on the flux linkage angle, the d-axis voltage command and q-axis voltage command output by the electromagnetic coupler current controller are transformed into coordinates to obtain the α-axis voltage command and β-axis voltage command input to the modulation module in the αβ-axis two-phase stationary coordinate system.

[0033] Specifically, the electromagnetic coupler has a gearbox-side mechanical port and a synchronous generator-side mechanical port, each corresponding to a specific mechanical rotational speed. To establish the field-oriented control model, in this embodiment, the gearbox-side mechanical port is designated as the rotor-side mechanical port, and the synchronous generator-side mechanical port is designated as the stator-side mechanical port. The electrical angular velocity corresponding to the mechanical rotational speed of the rotor-side mechanical port is the first electrical angular velocity, and the electrical angular velocity corresponding to the mechanical rotational speed of the stator-side mechanical port is the second electrical angular velocity. The aforementioned stator-side and rotor-side mechanical ports are used to characterize the relative motion relationship between the two mechanical ports of the electromagnetic coupler in the field-oriented control model, and are not intended to limit either mechanical port to a stationary state.

[0034] Accordingly, in the field-oriented control model, the electrical variables on the side connected to the electromagnetic coupler frequency converter are denoted as stator-side electrical variables, and the electrical variables on the other side electromagnetically coupled to it are denoted as rotor-side electrical variables; among them, stator-side electrical variables include stator voltage and stator current, and rotor-side electrical variables include rotor voltage, rotor current and rotor flux linkage.

[0035] The mechanical speeds at the gearbox-side mechanical port and the synchronous generator-side mechanical port can be obtained through encoder sampling and then filtered. The filter is used to suppress high-frequency noise caused by wind speed fluctuations, tower vibrations, etc., and to reduce the impact of speed fluctuations in the mechanical shaft systems at both ends on current harmonics and torque pulsations.

[0036] To maintain consistency with the parameters in the field-oriented control model, the second electrical angular velocity corresponding to the mechanical speed at the synchronous generator side mechanical port is denoted as the electrical angular velocity at the stator side mechanical port:

[0037] The first electrical angular velocity corresponding to the mechanical rotational speed at the gearbox-side mechanical port is denoted as the electrical angular velocity at the rotor-side mechanical port:

[0038] in, The electrical angular velocity of the stator-side mechanical port. ω is the electrical angular velocity of the rotor-side mechanical port.

[0039] Furthermore, the electromagnetic coupler synchronizes the electrical angular velocity. Let be the rotational electric angular velocity of the stator magnetic field, and let be the rotational velocity of the two-phase synchronous rotating coordinate system. In a two-phase synchronous rotating coordinate system, the current state equation of the electromagnetic coupler is:

[0040] In the formula, and These are the stator voltages along the d-axis and q-axis, respectively. and These are the stator currents along the d-axis and q-axis, respectively. and These are the components of the rotor flux along the d-axis and q-axis, respectively; , and These are stator inductance, rotor inductance, and mutual inductance, respectively. For stator resistance, For rotor resistance; Let be the leakage inductance factor, and satisfy:

[0041] For differential operators, Let be the rotor time constant, and:

[0042] The flux linkage state equation of the electromagnetic coupler is:

[0043] Let the two-phase synchronous rotating coordinate system be oriented based on the rotor magnetic field, then:

[0044] Substituting equation (03) into equation (02), we can obtain the synchronous electric angular velocity. and slip electric angular velocity They respectively satisfy:

[0045]

[0046] In control implementation, the slip electrical angular velocity can be determined based on the limited q-axis torque current setpoint and the d-axis excitation current setpoint, i.e.:

[0047] in, This is the setpoint for the q-axis torque current after limiting. This is the given value for the d-axis excitation current.

[0048] Furthermore, by integrating the synchronous electric angular velocity, the flux linkage angle is obtained:

[0049] in, The flux linkage angle is used for coordinate transformation of the voltage command and feedback current of the electromagnetic coupler. This allows the control process to obtain the d-axis feedback current and q-axis feedback current in the synchronous rotating coordinate system of the d and q axes, and transform the d-axis voltage command and q-axis voltage command to the two-phase stationary coordinate system. The electromagnetic coupler voltage is then controlled by the modulation module and inverter, thereby achieving decoupled control of torque and flux linkage.

[0050] When the electromagnetic coupler operates under high-speed-rate conditions, the stator resistance voltage drop accounts for a very small proportion of the stator voltage and is usually ignored. During stable operation of the electromagnetic coupler, the current dynamic term and flux linkage dynamic term in the stator voltage equation are zero. Therefore, according to equations (01), (02), and (03), the stator voltage equation for the electromagnetic coupler during high-speed-rate steady-state operation is:

[0051] The expression for the electromagnetic torque of the electromagnetic coupler during steady-state operation is:

[0052] In the formula, For electromagnetic torque, Let be the number of pole pairs of the motor. As can be seen from equation (8), the electromagnetic torque of the electromagnetic coupler is related to the stator current on the d-axis and the stator current on the q-axis. Therefore, under high-speed operation, the distribution relationship between the excitation current and the torque current needs to be considered simultaneously.

[0053] Step S1: Obtain the maximum voltage constraint, maximum current constraint, and maximum slip frequency constraint of the electromagnetic coupler.

[0054] Specifically, the electromagnetic coupler control structure is constrained by a triple constraint: maximum voltage, maximum current, and maximum slip frequency. Among these, the maximum current constraint... It mainly depends on the maximum allowable current value of the electromagnetic coupler stator winding and the maximum output current value of the converter; maximum voltage constraint. The maximum slip frequency constraint is affected by factors such as DC bus voltage, overmodulation strategy, and motor withstand voltage rating; it can be determined based on the mechanical characteristic curve of the electromagnetic coupler. In the field weakening region I, the operating range of the electromagnetic coupler is constrained by the maximum voltage and the maximum current; in the field weakening region II, the operating range of the electromagnetic coupler is constrained by the maximum voltage and the maximum slip frequency.

[0055] Considering multiple constraints, the dq-axis stator voltage of the electromagnetic coupler in the weak magnetic region should satisfy the following set of inequalities:

[0056] According to equation (7), the system of inequalities (9) can be equivalently transformed into the form of stator current:

[0057] According to equations (9) and (10), this embodiment adjusts the given value of the d-axis excitation current through voltage closed-loop regulation, and limits the given value of the q-axis torque current through current constraint and slip frequency constraint, so as to meet the stable control requirements of the electromagnetic coupler under the high speed change condition at the front end of the low wind speed area.

[0058] Step S2: Obtain the d-axis voltage command and q-axis voltage command of the electromagnetic coupler in the synchronous rotating coordinate system of the dq axis, and generate the voltage command amplitude based on the d-axis voltage command and q-axis voltage command.

[0059] Specifically, the d-axis voltage command and q-axis voltage command can be the dq-axis voltage commands output by the current controller to the modulation module. The current controller generates voltage commands based on the current setpoint of the electromagnetic coupler and the feedback current. The modulation module converts the voltage signal output by the current controller into a pulse signal for the inverter, and the inverter controls the electromagnetic coupler according to the pulse signal.

[0060] The steps for obtaining the d-axis voltage command and q-axis voltage command of the electromagnetic coupler in the synchronously rotating coordinate system of the dq axes, and generating the voltage command amplitude based on the d-axis voltage command and q-axis voltage command, include: The voltage command amplitude is generated based on the following formula:

[0061] in, This is the voltage command amplitude. This is a d-axis voltage command. This is the q-axis voltage command.

[0062] exist Figure 2 In the control structure diagram shown, the voltage command amplitude As a feedback quantity in the voltage closed loop, it is used to reflect the magnitude of the voltage command output by the current controller to the modulation module, thereby providing feedback basis for the generation of the subsequent d-axis excitation current setpoint.

[0063] Step S3: Generate the d-axis excitation current setpoint of the electromagnetic coupler based on the deviation between the maximum voltage constraint and the voltage command amplitude.

[0064] Specifically, such as Figure 2 As shown, to achieve high-speed operation of the electromagnetic coupler, a first voltage controller is set to adjust the excitation current to meet the voltage constraint conditions. The d-axis excitation current setpoint of the electromagnetic coupler is... It is determined by the output of the first voltage controller.

[0065] The steps for generating the d-axis excitation current setpoint for the electromagnetic coupler based on the deviation between the maximum voltage constraint and the voltage command amplitude include: The maximum voltage value in the maximum voltage constraint is used as the voltage setpoint, and the voltage command amplitude is used as the voltage feedback value. The excitation current regulation value is obtained by proportional-integral adjustment based on the difference between the voltage setpoint and the voltage feedback value. The excitation current adjustment value is limited according to the rated excitation current value and the minimum excitation current value to obtain the d-axis excitation current setpoint.

[0066] The voltage setpoint can be the maximum voltage value. The voltage feedback value can be the voltage command amplitude. Voltage given With voltage feedback The difference is adjusted by proportional-integral control and limited to output the d-axis excitation current setpoint. The upper limit of the limiting processing is the rated excitation current value. The lower limit of the limiting process is the minimum excitation current value. .in, This is the rated excitation current value. This is the minimum excitation current value. Through this closed-loop voltage regulation method, the excitation current setpoint can be adjusted when the electromagnetic coupler approaches its maximum voltage constraint, thereby meeting the system's maximum voltage limit.

[0067] Step S4: Based on the given value of the d-axis excitation current and the maximum current constraint, generate the q-axis torque current limit value under the current constraint. Based on the maximum slip frequency constraint, generate the q-axis torque current limit value under the slip frequency voltage form constraint and the q-axis torque current limit value under the slip frequency current form constraint. Based on the q-axis torque current limit value under the slip frequency voltage form constraint and the q-axis torque current limit value under the slip frequency current form constraint, generate the q-axis torque current limit value under the slip frequency constraint.

[0068] Specifically, the steps for generating the q-axis torque current limit value under current constraints, based on the d-axis excitation current setpoint and the maximum current constraint, include: Based on the maximum current value in the maximum current constraint and the given value of the d-axis excitation current, the q-axis torque current limit value under the current constraint is calculated according to the following formula:

[0069] in, This represents the q-axis torque current limit value under current constraint. This is the maximum current value. This is the given value for the d-axis excitation current.

[0070] Therefore, once the d-axis excitation current setpoint is determined, the remaining usable range of the q-axis torque current under current constraints can be determined based on the system's maximum current limit, so that the d-axis excitation current and the q-axis torque current satisfy the current constraint conditions.

[0071] The steps for generating q-axis torque and current limits under both slip frequency voltage and slip frequency current constraints, based on the maximum slip frequency constraint, include: like Figure 2 As shown, the slip frequency constraint module includes a second voltage controller and a slip frequency constraint calculation stage. The second voltage controller is used to generate the q-axis torque current limit value under the slip frequency voltage form constraint, and the slip frequency constraint calculation stage is used to generate the q-axis torque current limit value under the slip frequency current form constraint.

[0072] For the slip frequency voltage form constraint, the setpoint of the second voltage controller is the maximum voltage value and The ratio of the two voltages is such that the feedback from the second voltage controller is the absolute value of the d-axis voltage command. That is, the setpoint for the second voltage controller is:

[0073] The feedback from the second voltage controller is:

[0074] in, This is the maximum voltage value. This is the d-axis voltage command. The second voltage controller responds according to the voltage given. With voltage feedback The difference between them is adjusted by proportional-integral scaling and limiting, and the output is the q-axis torque current limiting value under the constraint of slip frequency voltage. .

[0075] For slip frequency current form constraints, the slip frequency constraint calculation step calculates the q-axis torque current limit value under slip frequency current form constraints according to the d-axis excitation current setpoint and leakage inductance factor, using the following formula:

[0076] in, This represents the q-axis torque current limit value under slip frequency current constraints. The given value for the d-axis excitation current. This is the leakage sensitivity factor.

[0077] The q-axis torque current limit under slip frequency constraint is generated by summing the q-axis torque current limit under slip frequency voltage constraint and the q-axis torque current limit under slip frequency current constraint; wherein, the q-axis torque current limit under slip frequency constraint satisfies:

[0078] in, This is the q-axis torque current limiting value under slip frequency constraints. This represents the q-axis torque current limiting value under slip frequency voltage constraints. This is the q-axis torque current limit value under the slip frequency current form constraint.

[0079] In this way, the slip frequency current form constraint can directly set the q-axis torque current limit value under slip frequency constraint to near the target range, thereby improving response speed and mitigating overshoot caused by controller saturation. The slip frequency voltage form constraint can perform closed-loop correction through a second voltage controller, reducing the impact of parameter offset on the q-axis torque current limit value under slip frequency constraint. Therefore, the combined effect of slip frequency current form constraint and slip frequency voltage form constraint can balance the speed of slip frequency constraint processing and parameter robustness.

[0080] Step S5: Generate the final q-axis torque current limit value based on the q-axis torque current limit value under current constraint and the q-axis torque current limit value under slip frequency constraint.

[0081] Specifically, the final limit value of the q-axis torque current of the electromagnetic coupler can be determined based on the q-axis torque current limit value under current constraints. q-axis torque current limiting value under slip frequency constraint The limit value for torque current is determined jointly. and The smaller of the two, namely:

[0082] in, This is the final limiting value for the q-axis torque current. This represents the q-axis torque current limit value under current constraint. This is the q-axis torque current limit value under the slip frequency constraint. By taking the smaller of the two values ​​as the final limit value, the q-axis torque current can simultaneously satisfy both the maximum current constraint and the maximum slip frequency constraint.

[0083] Before performing step S6, an initial setpoint value for the q-axis torque current is generated. Specifically, the method further includes: When the electromagnetic coupler is in the speed difference closed-loop control mode, the initial setpoint of the q-axis torque current is generated based on the speed difference setpoint and the actual speed difference. Alternatively, when the electromagnetic coupler is in torque closed-loop control mode, the initial setpoint of the q-axis torque current is generated based on the torque setpoint and the actual torque.

[0084] In the specific control process, based on the current control mode of the electromagnetic coupler, one of the outputs of the speed difference closed-loop control and the torque closed-loop control is selected as the initial setpoint of the q-axis torque current, and the initial setpoint of the q-axis torque current is sent to the subsequent torque current limiting circuit.

[0085] In the speed difference closed-loop control mode, the deviation between the speed difference setpoint and the actual speed difference is input into the proportional-integral adjustment loop to obtain the initial setpoint value of the q-axis torque current; in the torque closed-loop control mode, the deviation between the torque setpoint and the actual torque is input into the proportional-integral adjustment loop to obtain the initial setpoint value of the q-axis torque current.

[0086] Specifically, such as Figure 2 As shown, the electromagnetic coupler can operate in either speed difference closed-loop control mode or torque closed-loop control mode. When using speed difference closed-loop control mode, the speed difference setpoint can be used as the control method. Difference from actual speed The deviation between the values ​​generates the initial setpoint for the q-axis torque current; when using torque closed-loop control mode, the torque setpoint can be used as the initial setpoint. and actual torque The deviation between the two values ​​generates the initial setpoint for the q-axis torque current. The outputs of the speed difference closed-loop control mode and the torque closed-loop control mode are limited and used to determine the setpoint for the q-axis torque current of the electromagnetic coupler, thereby achieving control over the speed difference or electromagnetic torque of the electromagnetic coupler.

[0087] Step S6: Limit the initial setpoint of the q-axis torque current to within the final limit value of the q-axis torque current to obtain the limited setpoint of the q-axis torque current, and control the electromagnetic coupler according to the setpoint of the d-axis excitation current and the limited setpoint of the q-axis torque current.

[0088] Specifically, the initial setpoint of the q-axis torque current generated by the speed difference closed-loop control mode or the torque closed-loop control mode is limited to the final limit value of the q-axis torque current. Within this range, the q-axis torque current setpoint after limiting is obtained. Simultaneously, the d-axis excitation current setpoint obtained in step S3 is... With the limited q-axis torque current setpoint Input current control module.

[0089] The current control module consists of a current controller, used to regulate the electromagnetic coupler current so that it quickly tracks the current command. Specifically, the current controller adjusts the current according to the d-axis excitation current command. q-axis torque current setpoint after limiting d-axis feedback current and q-axis feedback current Generate d-axis voltage command and q-axis voltage command The d-axis voltage command output by the current controller. and q-axis voltage command After coordinate system transformation, the voltage command for the modulation module is obtained. The modulation module converts the voltage signal output by the current controller into a pulse signal for the inverter. The inverter controls the electromagnetic coupler according to the pulse signal.

[0090] like Figure 2 As shown, the control structure also includes a field orientation module. The field orientation module is used to calculate the synchronous electric angular velocity and flux linkage angle based on the first electric angular velocity corresponding to the mechanical speed of the gearbox-side mechanical port of the electromagnetic coupler, the second electric angular velocity corresponding to the mechanical speed of the synchronous generator-side mechanical port, the slip electric angular velocity, and the rotor time constant. Specifically, the mechanical speeds of the synchronous generator-side mechanical port and the gearbox-side mechanical port are sampled by an encoder and filtered by a filter to obtain the values ​​in the field orientation control model. and Slip electrical angular velocity according to and The product is determined; synchronous electric angular velocity according to , and Confirmed; synchronous electric angular velocity The flux linkage angle is obtained by integration. Magnetic flux angle Used for coordinate system transformation to enable the conversion of electromagnetic coupler voltage and current between a three-phase stationary coordinate system, a two-phase stationary coordinate system, and a dq-axis synchronous rotating coordinate system.

[0091] Specifically, the three-phase current of the electromagnetic coupler The current in the two-phase stationary coordinate system can be obtained through abc / αβ coordinate transformation. Then, after coordinate system transformation based on flux linkage angle, the d-axis feedback current in the synchronous rotating coordinate system of the dq axis is obtained. and q-axis feedback current The dq-axis voltage command output by the current controller can be transformed to obtain the voltage command in the two-phase stationary coordinate system for the modulation module. Then, the modulation module and inverter act on the electromagnetic coupler.

[0092] A voltage-closed-loop electromagnetic coupler high-speed control structure may include a voltage constraint module, a speed difference or torque control module, a slip frequency constraint module, a current constraint module, a current control module, a modulation module, and a field orientation module. The system comprises several modules: a voltage constraint module (consisting of a first voltage controller and an excitation current limiting circuit), used to meet the system's maximum voltage limit and adjust the d-axis excitation current setpoint; a speed difference or torque control module (consisting of a speed difference controller or a torque controller), used to control the speed difference or electromagnetic torque of the electromagnetic coupler; a slip frequency constraint module (consisting of a second voltage controller and a slip frequency constraint calculation circuit), whereby the second voltage controller generates the q-axis torque current limiting value under slip frequency voltage constraints, and the slip frequency constraint calculation circuit generates the q-axis torque current limiting value under slip frequency current constraints, both used together to meet the maximum slip frequency limit and adjust the q-axis torque current; a current constraint module (consisting of calculation expressions for maximum current and excitation current), used to meet the system's maximum current limit; a current control module (consisting of a current controller), used to adjust the electromagnetic coupler current to track the current setpoint; a modulation module (converting the voltage signal output by the current controller into a pulse signal for the inverter); and a field orientation module (calculating the synchronous electric angular velocity and flux linkage angle to achieve coordinate system transformation).

[0093] By employing a voltage closed-loop feedback voltage command amplitude, this embodiment can improve the DC bus voltage utilization rate. Through the slip frequency current form constraint in the slip frequency constraint module, the q-axis torque current limit value under slip frequency constraint can be set to near the target range, mitigating overshoot caused by controller saturation. Through the slip frequency voltage form constraint in the slip frequency constraint module, closed-loop correction can be performed using a second voltage controller, reducing the impact of parameter offset on the q-axis torque current limit value under slip frequency constraint. Therefore, the combined effect of slip frequency current form constraint and slip frequency voltage form constraint can balance the speed of slip frequency constraint processing and parameter robustness.

[0094] Through the above steps, this embodiment can coordinate and allocate the d-axis excitation current setpoint and q-axis torque current setpoint under high-speed operation conditions at the front end in low wind speed areas, based on maximum voltage constraints, voltage command amplitude, current constraints, and slip frequency constraints. This allows the electromagnetic coupler to still have a high torque output capability even when limited by maximum voltage, maximum current, and maximum slip frequency. At the same time, by adjusting the d-axis excitation current setpoint of the electromagnetic coupler through a voltage closed-loop method, and by jointly determining the q-axis torque current limit value under slip frequency constraints through slip frequency voltage form constraints and slip frequency current form constraints, it can improve the DC bus voltage utilization rate, enhance the adaptability of control parameters, broaden the speed regulation range of wind turbine units based on electromagnetic front-end speed regulation, improve wind energy utilization in low wind speed areas, and enhance the stable operation capability of the unit within a wide speed regulation range.

[0095] Example 2 like Figure 3 As shown, based on the same inventive concept as the above embodiments, the present invention also provides a voltage-closed-loop electromagnetic coupler high-speed control device, applied to the electromagnetic coupler control of wind turbine generators based on electromagnetic front-end speed regulation under high-speed front-end conditions in low wind speed areas. The device can be used to execute the voltage-closed-loop electromagnetic coupler high-speed control method of Embodiment 1. The device includes: a constraint acquisition module, a voltage command amplitude generation module, a first voltage controller, a current constraint processing module, a slip frequency constraint processing module, a final amplitude limiting generation module, a torque current limiting module, and a current controller.

[0096] The constraint acquisition module is used to acquire the maximum voltage constraint, maximum current constraint, and maximum slip frequency constraint of the electromagnetic coupler.

[0097] Specifically, the maximum current constraint can be the maximum current value. Maximum current value It mainly depends on the maximum allowable current value of the electromagnetic coupler stator winding and the maximum output current value of the frequency converter; the maximum voltage constraint can be the maximum voltage value. Maximum voltage value The maximum slip frequency constraint is determined based on the mechanical characteristic curve of the electromagnetic coupler, influenced by factors such as DC bus voltage, overmodulation strategy, and motor withstand voltage rating. In the field weakening region I, the operating range of the electromagnetic coupler is constrained by the maximum voltage and maximum current; in the field weakening region II, the operating range is constrained by both the maximum voltage and maximum slip frequency.

[0098] The low-wind-speed front-end high-ratio speed regulation condition refers to the situation where, when a wind turbine based on electromagnetic front-end speed regulation operates in a low-wind-speed area, the speed ratio of the electromagnetic coupler is higher than that under rated operating conditions. The device in this embodiment is applicable to this condition, but it is not necessary to determine whether the electromagnetic coupler is in this condition beforehand during the control process. When the voltage command amplitude is close to the maximum voltage constraint, the first voltage controller can automatically adjust the d-axis excitation current setpoint, and adjust the q-axis torque current setpoint in combination with the maximum current constraint and the maximum slip frequency constraint, so that the electromagnetic coupler meets multiple constraint conditions.

[0099] In one implementation, the device further includes a magnetic field orientation module. The magnetic field orientation module is used to acquire a first electrical angular velocity corresponding to the mechanical rotational speed of the gearbox-side mechanical port of the electromagnetic coupler, and a second electrical angular velocity corresponding to the mechanical rotational speed of the synchronous generator-side mechanical port of the electromagnetic coupler; determine the slip electrical angular velocity based on the q-axis torque current setpoint and the d-axis excitation current setpoint; generate a synchronous electrical angular velocity based on the first electrical angular velocity, the second electrical angular velocity, and the slip electrical angular velocity; and generate a flux linkage angle based on the synchronous electrical angular velocity; perform coordinate transformation on the feedback current of the electromagnetic coupler based on the flux linkage angle to obtain the d-axis feedback current and q-axis feedback current in the dq-axis synchronous rotating coordinate system; and perform coordinate transformation on the d-axis voltage command and q-axis voltage command output by the electromagnetic coupler current controller based on the flux linkage angle to obtain the α-axis voltage command and β-axis voltage command input to the modulation module in the αβ-axis two-phase stationary coordinate system.

[0100] Specifically, the electromagnetic coupler has a gearbox-side mechanical port and a synchronous generator-side mechanical port, each corresponding to a specific mechanical rotational speed. To establish the field-oriented control model, in this embodiment, the gearbox-side mechanical port is designated as the rotor-side mechanical port, and the synchronous generator-side mechanical port is designated as the stator-side mechanical port. The electrical angular velocity corresponding to the mechanical rotational speed of the rotor-side mechanical port is the first electrical angular velocity, and the electrical angular velocity corresponding to the mechanical rotational speed of the stator-side mechanical port is the second electrical angular velocity. The aforementioned stator-side and rotor-side mechanical ports are used to characterize the relative motion relationship between the two mechanical ports of the electromagnetic coupler in the field-oriented control model, and are not intended to limit either mechanical port to a stationary state.

[0101] To maintain consistency with the parameters in the field-oriented control model, the second electrical angular velocity corresponding to the mechanical speed at the synchronous generator side mechanical port is denoted as the electrical angular velocity at the stator side mechanical port:

[0102] The first electrical angular velocity corresponding to the mechanical rotational speed at the gearbox-side mechanical port is denoted as the electrical angular velocity at the rotor-side mechanical port:

[0103] in, The electrical angular velocity of the stator-side mechanical port. ω is the electrical angular velocity of the rotor-side mechanical port.

[0104] The field orientation module can generate slip electrical angular velocity based on the limited q-axis torque current setpoint and the d-axis excitation current setpoint.

[0105] in, The slip electrical angular velocity, The rotor time constant, This is the setpoint for the q-axis torque current after limiting. The given value for the d-axis excitation current. The rotor time constant satisfies:

[0106] in, For rotor inductance, This represents the rotor resistance.

[0107] The magnetic field orientation module is also used to generate synchronous electric angular velocity according to the following formula:

[0108] in, For synchronous electric angular velocity, This represents the difference between the corresponding electrical angular velocities of the two mechanical ports of the electromagnetic coupler.

[0109] Furthermore, the magnetic field orientation module is used to integrate the synchronous electric angular velocity to obtain the flux linkage angle:

[0110] in, The flux linkage angle is used for coordinate transformation of the electromagnetic coupler feedback current, enabling the acquisition of the d-axis and q-axis feedback currents in a synchronously rotating coordinate system during control, thereby achieving decoupled control of torque and flux linkage.

[0111] The voltage command amplitude generation module is used to obtain the d-axis voltage command and q-axis voltage command of the electromagnetic coupler in the dq-axis synchronous rotating coordinate system, and generate the voltage command amplitude based on the d-axis voltage command and q-axis voltage command.

[0112] Specifically, the d-axis voltage command and q-axis voltage command can be the dq-axis voltage commands output by the current controller to the modulation module. The voltage command amplitude generation module can generate the voltage command amplitude based on the following formula:

[0113] in, This is the voltage command amplitude. This is a d-axis voltage command. This is the q-axis voltage command.

[0114] Voltage command amplitude It can be used as the voltage feedback value of the first voltage controller to reflect the magnitude of the voltage command output by the current controller to the modulation module.

[0115] The first voltage controller is used to generate the d-axis excitation current setpoint of the electromagnetic coupler based on the deviation between the maximum voltage constraint and the voltage command amplitude.

[0116] Specifically, the first voltage controller is used to take the maximum voltage value in the maximum voltage constraint as the voltage setpoint, the voltage command amplitude as the voltage feedback value, and perform proportional-integral adjustment based on the difference between the voltage setpoint and the voltage feedback value to obtain the excitation current adjustment value; the first voltage controller is also used to limit the excitation current adjustment value according to the rated excitation current value and the minimum excitation current value to obtain the d-axis excitation current setpoint.

[0117] The maximum voltage value can be The voltage command amplitude can be The d-axis excitation current setpoint can be The upper limit of the limiting processing can be the rated excitation current value. The lower limit of the limiting process can be the minimum excitation current value. By adjusting the excitation current using the first voltage controller, the voltage constraint conditions of the electromagnetic coupler can be met.

[0118] The current constraint processing module is used to generate the q-axis torque current limit value under current constraint based on the d-axis excitation current setpoint and the maximum current constraint.

[0119] Specifically, the current constraint processing module can calculate the q-axis torque current limit value under the current constraint according to the following formula, based on the maximum current value in the maximum current constraint and the d-axis excitation current setpoint:

[0120] in, This represents the q-axis torque current limit value under current constraint. This is the maximum current value. This is the given value for the d-axis excitation current.

[0121] The current constraint processing module can determine the remaining usable range of the q-axis torque current under current constraints after the d-axis excitation current setpoint is determined, based on the system's maximum current limit.

[0122] The slip frequency constraint processing module is used to generate q-axis torque current limit values ​​under slip frequency voltage form constraint and slip frequency current form constraint based on the maximum slip frequency constraint, and to generate q-axis torque current limit values ​​under slip frequency constraint based on the q-axis torque current limit values ​​under slip frequency voltage form constraint and slip frequency current form constraint.

[0123] Specifically, the slip frequency constraint processing module includes a second voltage controller and a slip frequency constraint calculation stage. The second voltage controller is used to generate the q-axis torque current limit value under the slip frequency voltage form constraint; the slip frequency constraint calculation stage is used to generate the q-axis torque current limit value under the slip frequency current form constraint.

[0124] For slip frequency voltage form constraints, the second voltage controller is used to determine the maximum voltage value in the maximum voltage constraint and... The ratio generates the slip frequency constraint voltage setpoint, and the slip frequency constraint voltage feedback value is generated based on the absolute value of the d-axis voltage command; the second voltage controller is also used to perform proportional-integral adjustment and limiting processing based on the difference between the slip frequency constraint voltage setpoint and the slip frequency constraint voltage feedback value, so as to obtain the q-axis torque current limiting value under slip frequency voltage constraint.

[0125] Specifically, the setpoint for the second voltage controller can be:

[0126] The feedback from the second voltage controller can be:

[0127] in, This is the maximum voltage value. This is the d-axis voltage command. Voltage setpoint. With voltage feedback After proportional-integral regulation and limiting, the difference is used to output the q-axis torque current limiting value under the constraint of slip frequency voltage. .

[0128] For slip frequency current form constraints, the slip frequency constraint calculation step is used to calculate the q-axis torque current limit value under slip frequency current form constraints based on the d-axis excitation current setpoint and leakage inductance factor, according to the following formula:

[0129] in, This represents the q-axis torque current limit value under slip frequency current constraints. The given value for the d-axis excitation current. This is the leakage sensitivity factor.

[0130] Furthermore, the slip frequency constraint processing module is used to generate the q-axis torque current limit value under slip frequency constraint based on the sum of the q-axis torque current limit value under slip frequency voltage constraint and the q-axis torque current limit value under slip frequency current constraint.

[0131] in, This is the q-axis torque current limiting value under slip frequency constraints. This represents the q-axis torque current limiting value under slip frequency voltage constraints. This is the q-axis torque current limit value under the slip frequency current form constraint.

[0132] Therefore, the slip frequency current form constraint can set the q-axis torque current limit value under slip frequency constraint to near the target range, mitigating overshoot caused by controller saturation; the slip frequency voltage form constraint can perform closed-loop correction through a second voltage controller, reducing the impact of parameter offset on the q-axis torque current limit value under slip frequency constraint. The combined effect of these two methods can balance the speed of slip frequency constraint processing with parameter robustness.

[0133] The final limiting generation module is used to generate the final limiting value of q-axis torque current based on the q-axis torque current limiting value under current constraint and the q-axis torque current limiting value under slip frequency constraint.

[0134] Specifically, the final limiting generation module can limit the q-axis torque current under current constraints. q-axis torque current limiting value under slip frequency constraint The smaller value in the range is determined as the final limit value of the q-axis torque current. ,Right now:

[0135] in, This is the final limit value for the q-axis torque current. The final limit generation module ensures that subsequent q-axis torque current setpoints simultaneously meet both the maximum current constraint and the maximum slip frequency constraint.

[0136] The torque current limiting module is used to limit the initial setpoint of the q-axis torque current to within the final limit value of the q-axis torque current, thus obtaining the limited q-axis torque current setpoint.

[0137] Specifically, the initial setpoint for the q-axis torque current can be output by either the speed difference controller or the torque controller. When the electromagnetic coupler is in speed difference closed-loop control mode, the speed difference controller generates the initial setpoint for the q-axis torque current based on the speed difference setpoint and the actual speed difference; when the electromagnetic coupler is in torque closed-loop control mode, the torque controller generates the initial setpoint for the q-axis torque current based on the torque setpoint and the actual torque. The torque current limiting module limits the initial setpoint for the q-axis torque current to the final limit value of the q-axis torque current. Within this range, the q-axis torque current setpoint after limiting is obtained. .

[0138] The current controller is used to control the electromagnetic coupler based on the given value of the d-axis excitation current and the given value of the q-axis torque current after limiting.

[0139] Specifically, the current controller can be based on the given value of the d-axis excitation current. q-axis torque current setpoint after limiting d-axis feedback current and q-axis feedback current Generate d-axis voltage command and q-axis voltage command The current controller is used to regulate the electromagnetic coupler current, enabling the electromagnetic coupler current to quickly track the current command.

[0140] In one implementation, the device may further include a modulation module, an inverter, a coordinate system transformation module, an encoder, and a filter. The modulation module converts the voltage signal output by the current controller into a pulse signal for the inverter, which then drives the electromagnetic coupler based on the pulse signal. The encoder acquires the mechanical speed at the gearbox-side mechanical port and the mechanical speed at the synchronous generator-side mechanical port. The filter processes the mechanical speed acquired by the encoder to suppress high-frequency noise caused by wind speed fluctuations and tower vibration. The coordinate system transformation module enables the mutual conversion of the electromagnetic coupler voltage and current between a three-phase stationary coordinate system, a two-phase stationary coordinate system, and a dq-axis synchronous rotating coordinate system based on the flux linkage angle.

[0141] Specifically, the three-phase current of the electromagnetic coupler The current in the two-phase stationary coordinate system can be obtained through abc / αβ coordinate transformation. Then, after coordinate system transformation based on flux linkage angle, the d-axis feedback current in the synchronous rotating coordinate system of the dq axis is obtained. and q-axis feedback current The dq-axis voltage command output by the current controller can be transformed to obtain the voltage command in the two-phase stationary coordinate system for the modulation module. Then, the modulation module and inverter act on the electromagnetic coupler.

[0142] The above modules can be implemented using software modules, hardware modules, or a combination of both. The device uses a first voltage controller to adjust the d-axis excitation current setpoint based on a voltage closed-loop, and uses a current constraint processing module and a slip frequency constraint processing module to jointly limit the q-axis torque current setpoint. This ensures that the electromagnetic coupler simultaneously meets the constraints of maximum voltage, maximum current, and maximum slip frequency under high-speed operation conditions at the front end in low wind speed areas, thereby improving the torque output capability of the electromagnetic coupler under high-speed operation conditions.

[0143] In summary, this embodiment adjusts the d-axis excitation current setpoint of the electromagnetic coupler through a voltage closed-loop method, and limits the q-axis torque current setpoint by combining maximum current constraints, slip frequency voltage form constraints, and slip frequency current form constraints. This allows the electromagnetic coupler to balance voltage utilization, current carrying capacity, and slip frequency limitation under high-ratio speed regulation conditions at the front end in low wind speed areas. Consequently, it improves the torque output capability of the electromagnetic coupler at high speed ratios, broadens the speed regulation range of wind turbines based on electromagnetic front-end speed regulation, increases wind energy utilization in low wind speed areas, and enhances the stable operation capability of the unit over a wide speed regulation range.

[0144] Example 3 like Figure 4 As shown, the present invention also provides an electronic device 100 for implementing a voltage-closed-loop electromagnetic coupler high-speed control method; The electronic device 100 includes a memory 101, at least one processor 102, a computer program 103 stored in the memory 101 and executable on at least one processor 102, and at least one communication bus 104.

[0145] The memory 101 can be used to store the computer program 103. The processor 102 implements the high-speed control method of electromagnetic coupler based on voltage closed loop in Embodiment 1 by running or executing the computer program stored in the memory 101 and calling the data stored in the memory 101.

[0146] The memory 101 may primarily include a program storage area and a data storage area. The program storage area may store the operating system, application programs required for at least one function (such as sound playback function, image playback function, etc.), etc.; the data storage area may store data created based on the use of the electronic device 100 (such as audio data), etc. In addition, the memory 101 may include non-volatile memory, such as hard disk, RAM, plug-in hard disk, smart media card (SMC), secure digital (SD) card, flash card, at least one disk storage device, flash memory device, or other non-volatile solid-state storage device.

[0147] At least one processor 102 may be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. Processor 102 may be a microprocessor or any conventional processor. Processor 102 is the control center of electronic device 100, connecting various parts of electronic device 100 via various interfaces and lines.

[0148] The memory 101 in the electronic device 100 stores multiple instructions to implement a high-speed control method for an electromagnetic coupler based on voltage closed-loop, and the processor 102 can execute multiple instructions to achieve: obtaining the maximum voltage constraint, maximum current constraint and maximum slip frequency constraint of the electromagnetic coupler; Obtain the d-axis voltage command and q-axis voltage command of the electromagnetic coupler in the synchronous rotating coordinate system of dq-axis, and generate the voltage command amplitude based on the d-axis voltage command and q-axis voltage command; The d-axis excitation current setpoint of the electromagnetic coupler is generated based on the deviation between the maximum voltage constraint and the voltage command amplitude. Based on the given value of the d-axis excitation current and the maximum current constraint, the q-axis torque current limit value under the current constraint is generated. Based on the maximum slip frequency constraint, the q-axis torque current limit value under the slip frequency voltage form constraint and the q-axis torque current limit value under the slip frequency current form constraint are generated. Based on the q-axis torque current limit value under the slip frequency voltage form constraint and the q-axis torque current limit value under the slip frequency current form constraint, the q-axis torque current limit value under the slip frequency constraint is generated. Based on the q-axis torque current limit value under current constraint and the q-axis torque current limit value under slip frequency constraint, the final q-axis torque current limit value is generated. The initial setpoint of the q-axis torque current is limited to the final limit value of the q-axis torque current to obtain the limited q-axis torque current setpoint. The electromagnetic coupler is then controlled based on the d-axis excitation current setpoint and the limited q-axis torque current setpoint.

[0149] Example 4 If the modules / units integrated in the electronic device 100 are implemented as software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, all or part of the processes in the methods of the above embodiments of the present invention can also be implemented by a computer program instructing related hardware. The computer program can be stored in a computer-readable storage medium, and when executed by a processor, it can implement the steps of the various method embodiments described above. The computer program includes computer program code, which can be in the form of source code, object code, executable files, or certain intermediate forms. The computer-readable medium can include: any entity or device capable of carrying computer program code, recording media, USB flash drives, portable hard drives, magnetic disks, optical disks, computer memory, and read-only memory (ROM).

[0150] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0151] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0152] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0153] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0154] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0155] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A high-speed variable transmission control method for electromagnetic couplers based on voltage closed-loop control, characterized in that, An electromagnetic coupler control method applied to wind turbines with electromagnetic front-end speed regulation in low-wind-speed areas under high-speed-ratio front-end speed change conditions includes: Obtain the maximum voltage constraint, maximum current constraint, and maximum slip frequency constraint of the electromagnetic coupler; Obtain the d-axis voltage command and q-axis voltage command of the electromagnetic coupler in the dq-axis synchronous rotating coordinate system, and generate the voltage command amplitude based on the d-axis voltage command and q-axis voltage command; The d-axis excitation current setpoint of the electromagnetic coupler is generated based on the deviation between the maximum voltage constraint and the voltage command amplitude. Based on the given d-axis excitation current and the maximum current constraint, a q-axis torque current limit value under current constraint is generated. Based on the maximum slip frequency constraint, q-axis torque current limit values ​​under slip frequency voltage form constraint and slip frequency current form constraint are generated. Based on the q-axis torque current limit values ​​under slip frequency voltage form constraint and slip frequency current form constraint, a q-axis torque current limit value under slip frequency constraint is generated. Based on the q-axis torque current limit value under the current constraint and the q-axis torque current limit value under the slip frequency constraint, the final q-axis torque current limit value is generated. The initial setpoint of the q-axis torque current is limited to the final limit value of the q-axis torque current to obtain the limited q-axis torque current setpoint, and the electromagnetic coupler is controlled according to the d-axis excitation current setpoint and the limited q-axis torque current setpoint.

2. The high-speed control method for electromagnetic couplers based on voltage closed-loop as described in claim 1, characterized in that, Also includes: Obtain a first electrical angular velocity corresponding to the mechanical rotation speed of the gearbox-side mechanical port of the electromagnetic coupler, and a second electrical angular velocity corresponding to the mechanical rotation speed of the synchronous generator-side mechanical port of the electromagnetic coupler; The slip electrical angular velocity is determined based on the q-axis torque current setpoint and the d-axis excitation current setpoint, wherein the slip electrical angular velocity satisfies: in, The rotor time constant, The q-axis torque current setpoint. The given value for the d-axis excitation current; A synchronous electric angular velocity is generated based on the first electric angular velocity, the second electric angular velocity, and the slip electric angular velocity, wherein the synchronous electric angular velocity satisfies: in, For synchronous electric angular velocity, The first electric angular velocity, The second electric angular velocity, The slip electrical angular velocity; The flux linkage angle is generated based on the synchronous electric angular velocity, wherein the flux linkage angle satisfies: in, The flux linkage angle is mentioned above. Based on the flux linkage angle, the feedback current of the electromagnetic coupler is transformed to obtain the d-axis feedback current and q-axis feedback current in the dq-axis synchronous rotating coordinate system. Based on the flux linkage angle, the d-axis voltage command and q-axis voltage command output by the electromagnetic coupler current controller are transformed to obtain the α-axis voltage command and β-axis voltage command in the αβ-axis two-phase stationary coordinate system input to the modulation module.

3. The high-speed control method for electromagnetic couplers based on voltage closed-loop as described in claim 1, characterized in that, The steps of obtaining the d-axis voltage command and q-axis voltage command of the electromagnetic coupler in the dq-axis synchronous rotating coordinate system, and generating the voltage command amplitude based on the d-axis voltage command and q-axis voltage command include: The voltage command amplitude is generated based on the following formula: in, The voltage command amplitude, This refers to the d-axis voltage command. This refers to the q-axis voltage command.

4. The high-speed control method for electromagnetic couplers based on voltage closed-loop as described in claim 1, characterized in that, The step of generating the d-axis excitation current setpoint of the electromagnetic coupler based on the deviation between the maximum voltage constraint and the voltage command amplitude includes: Using the maximum voltage value in the maximum voltage constraint as the voltage setpoint and the voltage command amplitude as the voltage feedback value, proportional-integral adjustment is performed based on the difference between the voltage setpoint and the voltage feedback value to obtain the excitation current adjustment value; The excitation current adjustment value is limited by using the rated excitation current value as the maximum limit value and the minimum excitation current value as the minimum limit value, so as to obtain the d-axis excitation current setpoint value.

5. The high-speed control method for electromagnetic couplers based on voltage closed-loop as described in claim 1, characterized in that, The steps for generating the q-axis torque current limit value under current constraint based on the given d-axis excitation current value and the maximum current constraint include: Based on the maximum current value in the maximum current constraint and the given value of the d-axis excitation current, the q-axis torque current limit value under the current constraint is calculated according to the following formula: in, This is the q-axis torque current limit value under the aforementioned current constraint. The maximum current value, The given value for the d-axis excitation current.

6. The high-speed control method for electromagnetic couplers based on voltage closed-loop as described in claim 1, characterized in that, The steps for generating q-axis torque current limiting values ​​under slip frequency voltage form constraints and slip frequency current form constraints, based on the maximum slip frequency constraint, include: Based on the maximum voltage value and The ratio generates the slip frequency constraint voltage setpoint, and the slip frequency constraint voltage feedback value is generated based on the absolute value of the d-axis voltage command. Based on the difference between the given value of the slip frequency constraint voltage and the feedback value of the slip frequency constraint voltage, proportional-integral adjustment and limiting processing are performed to obtain the q-axis torque current limiting value under the slip frequency voltage constraint. Based on the given d-axis excitation current and leakage inductance factor, the q-axis torque current limit value under the slip frequency current constraint is calculated using the following formula: in, This is the q-axis torque current limit value under the slip frequency current form constraint. The given value for the d-axis excitation current. The leakage sensitivity factor is mentioned above.

7. The high-speed control method for electromagnetic couplers based on voltage closed-loop as described in claim 6, characterized in that, The step of generating the q-axis torque current limit value under the slip frequency constraint, based on the q-axis torque current limit value under the slip frequency voltage form constraint and the q-axis torque current limit value under the slip frequency current form constraint, includes: The q-axis torque current limit value under the slip frequency constraint is generated by summing the q-axis torque current limit value under the slip frequency voltage form constraint and the q-axis torque current limit value under the slip frequency current form constraint. Wherein, the q-axis torque current limiting value under the slip frequency constraint satisfies: in, This is the q-axis torque current limiting value under the slip frequency constraint. This refers to the q-axis torque current limiting value under the slip frequency voltage constraint. The value is the q-axis torque current limit under the slip frequency current form constraint.

8. A high-speed control device for electromagnetic couplers based on voltage closed-loop, characterized in that, An electromagnetic coupler control device is applied to wind turbine generators operating under high-speed-rate-change conditions at the front end in low-wind-speed regions, and the device includes: The constraint acquisition module is used to acquire the maximum voltage constraint, maximum current constraint, and maximum slip frequency constraint of the electromagnetic coupler. The voltage command amplitude generation module is used to obtain the d-axis voltage command and q-axis voltage command of the electromagnetic coupler in the dq-axis synchronous rotating coordinate system, and generate the voltage command amplitude based on the d-axis voltage command and q-axis voltage command; A first voltage controller is configured to generate a d-axis excitation current setpoint for the electromagnetic coupler based on the deviation between the maximum voltage constraint and the voltage command amplitude. The current constraint processing module is used to generate the q-axis torque current limit value under the current constraint based on the given value of the d-axis excitation current and the maximum current constraint. The slip frequency constraint processing module is used to generate q-axis torque current limit values ​​under slip frequency voltage form constraint and q-axis torque current limit values ​​under slip frequency current form constraint according to the maximum slip frequency constraint, and to generate q-axis torque current limit values ​​under slip frequency constraint according to the q-axis torque current limit values ​​under slip frequency voltage form constraint and q-axis torque current limit values ​​under slip frequency current form constraint. The final limiting generation module is used to generate the final limiting value of q-axis torque current based on the q-axis torque current limiting value under the current constraint and the q-axis torque current limiting value under the slip frequency constraint. The torque current limiting module is used to limit the initial setpoint of the q-axis torque current to within the final limit value of the q-axis torque current, so as to obtain the limited q-axis torque current setpoint. A current controller is used to control the electromagnetic coupler based on the given value of the d-axis excitation current and the given value of the q-axis torque current after limiting.

9. An electronic device, characterized in that, It includes a processor and a memory, the processor being used to execute a computer program stored in the memory to implement the voltage closed-loop electromagnetic coupler high-speed control method as described in any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores at least one instruction, which, when executed by a processor, implements the voltage-closed-loop electromagnetic coupler high-speed control method as described in any one of claims 1 to 7.

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