A current injection wideband impedance measurement device control method and system

Abstract

The application discloses a current injection wide-band impedance measuring device control method and system. The application generates three-phase control voltage of the wide-band impedance measuring device by collecting three-phase voltage of a grid-connected point of the wide-band impedance measuring device, output three-phase current and DC side voltage, adopting voltage outer loop control, current inner loop control, voltage feedforward control and carrier modulation, effectively realizes wide-band impedance measuring device control, and provides support for realizing accurate measurement of high-voltage, megawatt, wide-band impedance characteristics.

Description

Technical Field

[0001] The present invention relates to a current-injected wide-band impedance measurement device control method and system, belonging to the impedance measurement field of new energy power generation. Background Art

[0002] Renewable energy generation equipment such as wind turbines and photovoltaics is primarily comprised of converters, which are characterized by a high degree of power electronics and a tendency to exhibit negative impedance characteristics. Connecting these devices to the positive impedance grid creates a grid-connected system with the risk of oscillation. As the proportion of power electronics in the power system increases, the electromagnetic oscillations they cause are becoming increasingly prominent, posing a serious challenge to the safety and stability of the power system. To monitor the stability of power systems, some researchers have proposed an impedance scanning method. This method injects disturbance signals of varying frequencies into power electronics such as the grid and inverters, testing their impedance characteristics at varying frequencies. The system's stability margin is then assessed using methods such as Nyquist plots. Disturbance injection can be categorized into voltage and current injection. Current injection offers greater potential due to its less impact on the grid and equipment, making it more suitable for engineering applications.

[0003] The current injection method currently uses a wideband impedance measurement device to inject a disturbance current into the grid-connected system. This device includes an MMC module. Each phase of the MMC module consists of multiple cascaded sub-power modules. Each phase is connected to the grid-connected system via an RL filter inductor. Each sub-power module is composed of a full-bridge DC / AC converter, providing the disturbance current. The filter inductor in the RL filter performs high-frequency filtering on the output current of the MMC module, providing a well-shaped disturbance current. However, there is currently no control method for this wideband impedance measurement device. Summary of the Invention

[0004] The present invention provides a control method and system for a current-injected wide-band impedance measurement device, which solves the problems disclosed in the background technology.

[0005] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0006] A method for controlling a current-injected broadband impedance measurement device, comprising:

[0007] The collected u a 、u b 、u c and i a 、i b 、i c Convert to u respectively d 、u q and i d 、i q ; Among them, u a 、ub 、u c is the three-phase voltage at the grid connection point of the broadband impedance measurement device, i a 、i b 、i c is the three-phase current output by the broadband impedance measurement device, u d 、u q They are u in the rotating coordinate system a 、u b 、u c The d-axis component and q-axis component of i d 、i q They are respectively i in the rotating coordinate system a 、i b 、i c The d-axis component and q-axis component of

[0008] To u dc 、u dc_ref 、i a 、i b 、i c 、i a_ref 、i b_ref 、i c_ref Perform voltage outer loop control to obtain i d_ref ; Among them, u dc is the DC side voltage in the broadband impedance measurement device, u dc_ref is the preset DC side voltage reference value, i a_ref 、i b_ref 、i c_ref is the preset output current reference value, i d_ref is the d-axis component of the current inner loop reference value;

[0009] to i d_ref 、i q_ref 、i d 、i q Perform current inner loop control to obtain u d1 、u q1 ; Among them, u d1 、u q1 are the d-axis component and q-axis component of the inner loop control voltage, i q_ref The preset current inner loop reference value q-axis component;

[0010] To u d1 、u q1 、i d_ref 、i q_ref 、u d 、u q Perform voltage feedforward control to obtain u d3 、u q3 ; Among them, u d3 、uq3 are the d-axis component and q-axis component of the three-phase control voltage in the rotating coordinate system respectively;

[0011] To u d3 、u q3 Carrier modulation is performed to obtain u ca 、u cb 、u cc ; Among them, u ca 、u cb 、u cc Three-phase control voltage for the broadband impedance measuring device;

[0012] According to u ca 、u cb 、u cc Performs broadband impedance measurement device control.

[0013] The collected u a 、u b 、u c and i a 、i b 、i c Convert to u respectively d 、u q and i d 、i q ,include:

[0014] For the collected u a 、u b 、u c Perform phase-locked loop processing to obtain phase;

[0015] Phase and u a 、u b 、u c Perform abc / dq0 transformation to obtain u d 、u q ;

[0016] For the collected i a 、i b 、i c Perform abc / dq0 transformation to obtain i d 、i q .

[0017] To u dc 、u dc_ref 、i a 、i b 、i c 、i a_ref 、i b_ref 、i c_ref Perform voltage outer loop control to obtain i d_ref ,include:

[0018] will i a 、i b 、i c Respectively with i a_ref 、i b_ref 、i c_ref Make a difference, perform PI control on the difference, and obtain u dc_ref1 ; Among them, u dc_ref1 is the first reference value of the DC side voltage;

[0019] will u dc_ref and u dc_ref1 Add and get u dc_ref2 ; Among them, u dc_ref2 a second reference value of the DC side voltage;

[0020] will u dc with u dc_ref2 Take the difference and get Δu dc ; where Δu dc is the DC side voltage error;

[0021] Δu dc After PI control, we can obtain i d_ref .

[0022] to i d_ref 、i q_ref 、i d 、i q Perform current inner loop control to obtain u d1 、u q1 ,include:

[0023] will i d_ref with i d Take the difference and get Δi d ; Among them, Δi d is the d-axis component of the current error;

[0024] will i q_ref with i q Take the difference and get Δi q ; Among them, Δi q is the q-axis component of the current error;

[0025] Δi d After PI control in sequence, u is obtained d1 ;

[0026] Δi q After PI control in sequence, u is obtained q1 .

[0027] To u d1 、u q1 、i d_ref 、i q_ref、u d 、u q Perform voltage feedforward control to obtain u d3 、u q3 ,include:

[0028] will i d_ref The product of R, i q_ref The opposite of the product of wL, u d 、u d1 Add and get u d3 ; Where R is the filter resistance, L is the filter inductance, and w is the fundamental angular velocity;

[0029] will i q_ref The product of R, i d_ref The product of wL and u q 、u q1 Add and get u q3 .

[0030] To u d3 、u q3 Carrier modulation is performed to obtain u ca 、u cb 、u cc ,include:

[0031] To u d3 、u q3 Perform modulation ratio coefficient multiplication and dq0 / abc transformation in sequence to obtain u ma 、u mb 、u mc ; Among them, u ma 、u mb 、u mc is the three-phase modulated voltage;

[0032] To u dc Perform pressure equalization control and compare the results of pressure equalization control with u ma 、u mb 、u mc Add, pass the result of addition through PWM, and get u ca 、u cb 、u cc .

[0033] According to u ca 、u cb 、u cc Perform broadband impedance measurement device control, including:

[0034] According to u ca 、u cb 、u cc , obtain the duty cycle signal of the switch tube in the wide-band impedance measurement device and control the on and off of the switch tube.

[0035] A current injection broadband impedance measurement device control system, comprising:

[0036] Conversion module, the collected u a 、u b 、u c and i a 、i b 、i c Convert to u respectively d 、u q and i d 、i q ; Among them, u a 、u b 、u c is the three-phase voltage at the grid connection point of the broadband impedance measurement device, i a 、i b 、i c is the three-phase current output by the broadband impedance measurement device, u d 、u q They are u in the rotating coordinate system a 、u b 、u c The d-axis component and q-axis component of i d 、i q They are respectively i in the rotating coordinate system a 、i b 、i c The d-axis component and q-axis component of

[0037] Voltage outer loop control module, for u dc 、u dc_ref 、i a 、i b 、i c 、i a_ref 、i b_ref 、i c_ref Perform voltage outer loop control to obtain i d_ref ; Among them, u dc is the DC side voltage in the broadband impedance measurement device, u dc_ref is the preset DC side voltage reference value, i a_ref 、i b_ref 、i c_ref is the preset output current reference value, i d_ref is the d-axis component of the current inner loop reference value;

[0038] Current inner loop control module, i d_ref 、i q_ref 、i d 、i q Perform current inner loop control to obtain u d1 、u q1; Among them, u d1 、u q1 are the d-axis component and q-axis component of the inner loop control voltage, i q_ref The preset current inner loop reference value q-axis component;

[0039] Voltage feedforward control module, for u d1 、u q1 、i d_ref 、i q_ref 、u d 、u q Perform voltage feedforward control to obtain u d3 、u q3 ; Among them, u d3 、u q3 are the d-axis component and q-axis component of the three-phase control voltage in the rotating coordinate system respectively;

[0040] Carrier modulation module, for u d3 、u q3 Carrier modulation is performed to obtain u ca 、u cb 、u cc ; Among them, u ca 、u cb 、u cc Three-phase control voltage for the broadband impedance measuring device;

[0041] Device control module, according to u ca 、u cb 、u cc Performs broadband impedance measurement device control.

[0042] A computer-readable storage medium storing one or more programs, wherein the one or more programs include instructions that, when executed by a computing device, cause the computing device to execute a method for controlling a wide-band impedance measurement apparatus using current injection.

[0043] A computing device includes one or more processors, one or more memories, and one or more programs, wherein the one or more programs are stored in the one or more memories and configured to be executed by the one or more processors, and the one or more programs include instructions for executing a method for controlling a wide-band impedance measurement device using current injection.

[0044] The beneficial effects achieved by the present invention are as follows: the present invention collects the three-phase voltage at the grid connection point of the wide-band impedance measuring device, the output three-phase current and the DC side voltage, and adopts voltage outer loop control, current inner loop control, voltage feedforward control and carrier modulation to generate the three-phase control voltage of the wide-band impedance measuring device, thereby effectively realizing the control of the wide-band impedance measuring device and providing support for the accurate measurement of high-voltage, megawatt-level and wide-band impedance characteristics. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 It is a schematic diagram of the structure of the grid-connected system and the broadband impedance measurement device;

[0046] Figure 2 A schematic diagram of a control method for a wide-band impedance measurement device;

[0047] Figure 3 This is the impedance characteristic diagram of the resistive-inductive load. DETAILED DESCRIPTION

[0048] The present invention will be further described below in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention.

[0049] like Figure 1 As shown, the power grid and new energy power generation equipment (including wind turbines, DFIG, rectifiers, inverters, transformers) constitute a grid-connected system, and the R line is the line resistance, L line The broadband impedance measuring device includes an MMC module, each phase of which includes n cascaded sub-power module units (SM a1 ~SM an ), each phase passes through the RL filter (filter inductor L in the figure a , L b , L c , filter resistor R a 、R b 、R c ) is connected to the grid-connected system. Each sub-power module unit is composed of a full-bridge DC / AC converter to provide disturbance current. The filter inductor in the RL filter performs high-frequency filtering on the output current of the MMC module to provide a disturbance current with a good waveform.

[0050] Based on the above structure, Figure 2 As shown, a control method for a current injection wideband impedance measurement device includes the following steps:

[0051] Step 1: collect u a 、u b 、u c and i a 、i b 、i c Convert to u respectively d 、u q and i d 、i q ; Among them, u a 、u b 、u cis the three-phase voltage at the grid connection point of the broadband impedance measurement device, i a 、i b 、i c is the three-phase current output by the broadband impedance measurement device, u d 、u q They are u in the rotating coordinate system a 、u b 、u c The d-axis component and q-axis component of i d 、i q They are respectively i in the rotating coordinate system a 、i b 、i c The d-axis component and q-axis component of .

[0052] Step 2, for u dc 、u dc_ref 、i a 、i b 、i c 、i a_ref 、i b_ref 、i c_ref Perform voltage outer loop control to obtain i d_ref ; Among them, u dc is the DC side voltage in the broadband impedance measurement device, u dc_ref is the preset DC side voltage reference value, i a_ref 、i b_ref 、i c_ref is the preset output reference current, i d_ref is the d-axis component of the current inner loop reference value.

[0053] Step 3, for i d_ref 、i q_ref 、i d 、i q Perform current inner loop control to obtain u d1 、u q1 ; Among them, u d1 、u q1 are the d-axis component and q-axis component of the inner loop control voltage, i q_ref The preset q-axis component of the current inner loop reference value.

[0054] Step 4, for u d1 、u q1 、i d_ref 、i q_ref 、u d 、u q Perform voltage feedforward control to obtain u d3 、u q3 ; Among them, u d3 、u q3are the d-axis and q-axis components of the three-phase control voltage in the rotating coordinate system.

[0055] Step 5, for u d3 、u q3 Carrier modulation is performed to obtain u ca 、u cb 、u cc ; Among them, u ca 、u cb 、u cc It is the three-phase control voltage of the broadband impedance measurement device.

[0056] Step 6, according to u ca 、u cb 、u cc Performs broadband impedance measurement device control.

[0057] The above method generates the three-phase control voltage of the wide-band impedance measurement device by collecting the three-phase voltage at the grid connection point of the wide-band impedance measurement device, the output three-phase current and the DC side voltage, and adopts voltage outer loop control, current inner loop control, voltage feedforward control and carrier modulation, thereby effectively realizing the control of the wide-band impedance measurement device and providing support for the accurate measurement of high-voltage, megawatt-level, wide-band impedance characteristics.

[0058] At the starting point of each sampling cycle, the three-phase voltage u of the grid connection point of the wide-band impedance measurement device can be obtained through the AD sampling circuit. a 、u b 、u c , output three-phase current i a 、i b 、i c And the DC side voltage of the sub-power module unit, according to the DC side voltage of the sub-power module unit, the DC side voltage u in the broadband impedance measurement device can be calculated using the following formula dc ;

[0059]

[0060] Among them, u ij is the DC side voltage of the j-th sub-power module unit of the i-th phase, i=a,b,c, j=1,2,3,...,n.

[0061] To u a 、u b 、u c Perform phase-locked loop processing to obtain phase θ, and calculate θ and u a 、u b 、u c Perform abc / dq0 transformation to obtain u d 、u q , for the collected ia 、i b 、i c Perform abc / dq0 transformation to obtain i d 、i q .

[0062] will i a 、i b 、i c Respectively with i a_ref 、i b_ref 、i c_ref Make a difference, perform PI control on the difference, and obtain the first reference value u of the DC side voltage dc_ref1 , will u dc_ref and u dc_ref1 Add and get u dc_ref2 , will u dc and the second reference value u of the DC link voltage dc_ref2 Subtract and obtain the voltage error Δu dc , Δu dc After PI control, the current inner loop reference value d-axis component and q-axis component i are obtained d_ref .

[0063] Further i d_ref with i d The current error d-axis component Δi is obtained by subtracting d , change i q_ref with i q The current error q-axis component Δi is obtained by subtracting q , Δi d Obtain u through PI control d1 , Δi q Obtain u through PI control q1 .

[0064] will i d_ref The product of the filter resistance R, i q_ref The opposite of the product of wL, u d 、u d1 Add and get u d3 , change i q_ref The product of the filter resistance R, i d_ref The product of wL and u q 、u q1 Add and get u q3 ; Where L is the filter inductance and w is the fundamental angular velocity.

[0065] To u d3 、u q3 Perform modulation ratio coefficient multiplication and dq0 / abc transformation in sequence to obtain the three-phase modulation voltage u ma 、u mb 、umc , for u dc Perform pressure equalization control and compare the results of pressure equalization control with u ma 、u mb 、u mc Add, pass the result of addition through PWM, and get u ca 、u cb 、u cc , according to u ca 、u cb 、u cc The duty cycle signal of the switch tube in the wide-band impedance measuring device is obtained to control the on and off of the switch tube, thereby realizing control of the wide-band impedance measuring device.

[0066] Apply the above method to Figure 1 In the broadband impedance measurement device, the device injects current into the grid-connected system, which generates a response voltage. The injected current and voltage on the new energy power generation equipment side are obtained through the AD sampling circuit. According to the impedance calculation formula:

[0067]

[0068] Simplify the new energy power generation equipment to be equivalent to a resistor in series with an inductor R m +sL m The impedance characteristics of the resistive-inductive load are:

[0069]

[0070] The disturbance current frequency of the broadband impedance measurement device changes from low to high, and the impedance changes accordingly, and the impedance characteristics of the load are obtained. Figure 3 As shown, the measured value of the impedance load is almost consistent with the actual value, which verifies that the impedance measurement device and control method of the present invention are effective.

[0071] This wide-band impedance measurement device uses a current parallel injection method, which has little impact on the power grid and equipment, making it suitable for engineering applications. It also uses an independent capacitor for power supply, effectively avoiding the influence of power grid harmonics on the device's accurate measurement. At the same time, no other structures are added to the three-phase converter, thereby reducing the size and cost of the device while ensuring the quality of the output current.

[0072] Based on the same technical solution, the present invention also discloses a software system of the above method, a control system for a current injection broadband impedance measurement device, comprising:

[0073] Conversion module, the collected u a 、u b 、u c and i a 、i b 、i c Convert to u respectivelyd 、u q and i d 、i q ; Among them, u a 、u b 、u c is the three-phase voltage at the grid connection point of the broadband impedance measurement device, i a 、i b 、i c is the three-phase current output by the broadband impedance measurement device, u d 、u q They are u in the rotating coordinate system a 、u b 、u c The d-axis component and q-axis component of i d 、i q They are respectively i in the rotating coordinate system a 、i b 、i c The d-axis component and q-axis component of .

[0074] Voltage outer loop control module, for u dc 、u dc_ref 、i a 、i b 、i c 、i a_ref 、i b_ref 、i c_ref Perform voltage outer loop control to obtain i d_ref ; Among them, u dc is the DC side voltage in the broadband impedance measurement device, u dc_ref is the preset DC side voltage reference value, i a_ref 、i b_ref 、i c_ref is the preset output current reference value, i d_ref They are the d-axis components of the inner loop current reference values.

[0075] Current inner loop control module, i d_ref 、i q_ref 、i d 、i q Perform current inner loop control to obtain u d1 、u q1 ; Among them, u d1 、u q1 are the d-axis component and q-axis component of the inner loop control voltage, i q_ref The preset q-axis component of the current inner loop reference value.

[0076] Voltage feedforward control module, for u d1 、u q1 、i d_ref 、iq_ref 、u d 、u q Perform voltage feedforward control to obtain u d3 、u q3 ; Among them, u d3 、u q3 are the d-axis component and q-axis component of the three-phase control voltage in the rotating coordinate system respectively.

[0077] Carrier modulation module, for u d3 、u q3 Carrier modulation is performed to obtain u ca 、u cb 、u cc ; Among them, u ca 、u cb 、u cc It is the three-phase control voltage of the broadband impedance measurement device.

[0078] Device control module, according to u ca 、u cb 、u cc Performs broadband impedance measurement device control.

[0079] The data processing flow of each module in the above system is consistent with the flow of the corresponding steps of the method, and will not be repeated here.

[0080] Based on the same technical solution, the present invention also discloses a computer-readable storage medium storing one or more programs, wherein the one or more programs include instructions, which, when executed by a computing device, enable the computing device to perform a method for controlling a wide-band impedance measurement device with current injection.

[0081] Based on the same technical solution, the present invention also discloses a computing device, including one or more processors, one or more memories, and one or more programs, wherein the one or more programs are stored in the one or more memories and are configured to be executed by the one or more processors, and the one or more programs include instructions for executing a control method of a wide-band impedance measurement device for current injection.

[0082] It will be understood by those skilled in the art that embodiments of the present invention may be provided as methods, systems, or computer program products. Thus, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware. Furthermore, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0083] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowcharts and / or block diagrams, as well as combinations of processes and / or blocks in the flowcharts and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowcharts and / or block diagrams. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0084] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0085] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0086] The above are merely embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention are included in the scope of the claims of the present invention to be approved.

Claims

1. A control method for a current injection broadband impedance measurement device, characterized in that: include: The collected u a 、u b 、u c and i a 、i b 、i c Convert to u respectively d 、u q and i d 、i q ; Among them, u a 、u b 、u c is the three-phase voltage at the grid connection point of the broadband impedance measurement device, i a 、i b 、i c is the three-phase current output by the broadband impedance measurement device, u d 、u q They are u in the rotating coordinate system a 、u b 、u c The d-axis component and q-axis component of i d 、i q They are respectively i in the rotating coordinate system a 、i b 、i c The d-axis component and q-axis component of To u dc 、u dc_ref 、i a 、i b 、i c 、i a_ref 、i b_ref 、i c_ref Perform voltage outer loop control to obtain i d_ref ; Among them, u dc is the DC side voltage in the broadband impedance measurement device, u dc_ref is the preset DC side voltage reference value, i a_ref 、i b_ref 、i c_ref is the preset output current reference value, i d_ref is the d-axis component of the current inner loop reference value; to i d_ref 、i q_ref 、i d 、i q Perform current inner loop control to obtain u d1 、u q1 ; Among them, u d1 、u q1 are the d-axis component and q-axis component of the inner loop control voltage, i q_ref is the preset current inner loop reference value q-axis component; To u d1 、u q1 、i d_ref 、i q_ref 、u d 、u q Perform voltage feedforward control to obtain u d3 、u q3 ; Among them, u d3 、u q3 are the d-axis component and q-axis component of the three-phase control voltage in the rotating coordinate system respectively; To u d3 、u q3 Carrier modulation is performed to obtain u ca 、u cb 、u cc ; Among them, u ca 、u cb 、u cc Three-phase control voltage for the broadband impedance measuring device; According to u ca 、u cb 、u cc Conduct broadband impedance measurement device control; The above d1 、u q1 、i d_ref 、i q_ref 、u d 、u q Perform voltage feedforward control to obtain u d3 、u q3 ,include: will i d_ref The product of R, i q_ref The opposite of the product of wL, u d 、u d1 Add and get u d3 ; Where R is the filter resistance, L is the filter inductance, and w is the fundamental angular velocity; will i q_ref The product of R, i d_ref The product of wL and u q 、u q1 Add and get u q3 .

2. The method for controlling a current injection wideband impedance measurement device according to claim 1, wherein: The collected u a 、u b 、u c and i a 、i b 、i c Convert to u respectively d 、u q and i d 、i q , include: For the collected u a 、u b 、u c Perform phase-locked loop processing to obtain phase; Phase and u a 、u b 、u c Perform abc / dq0 transformation to obtain u d 、u q ; For the collected i a 、i b 、i c Perform abc / dq0 transformation to obtain i d 、i q .

3. The method for controlling a current injection wideband impedance measurement device according to claim 1, wherein: To u dc 、u dc_ref 、i a 、i b 、i c 、i a_ref 、i b_ref 、i c_ref Perform voltage outer loop control to obtain i d_ref , include: will i a 、i b 、i c Respectively with i a_ref 、i b_ref 、i c_ref Make a difference, perform PI control on the difference, and obtain u dc_ref1 ; Among them, u dc_ref1 is the first reference value of the DC side voltage; will u dc_ref and u dc_ref1 Add and get u dc_ref2 ; Among them, u dc_ref2 is the second reference value of the DC side voltage; will u dc with u dc_ref2 Take the difference and get Δu dc ; where Δu dc is the DC side voltage error; Δu dc After PI control, we can obtain i d_ref .

4. The method for controlling a current-injected broadband impedance measurement device according to claim 1, wherein: to i d_ref 、i q_ref 、i d 、i q Perform current inner loop control to obtain u d1 、u q1 , include: will i d_ref with i d Take the difference and get Δi d ; Among them, Δi d is the d-axis component of the current error; will i q_ref with i q Take the difference and get Δi q ; Among them, Δi q is the q-axis component of the current error; Δi d After PI control, we can get u d1 ; Δi q After PI control, we can get u q1 .

5. The control method of a current injection wideband impedance measurement device according to claim 1, characterized in that: To u d3 、u q3 Carrier modulation is performed to obtain u ca 、u cb 、u cc , include: To u d3 、u q3 Perform modulation ratio coefficient multiplication and dq0 / abc transformation in sequence to obtain u ma 、u mb 、u mc ; Among them, u ma 、u mb 、u mc is the three-phase modulated voltage; To u dc Perform pressure equalization control and compare the results of pressure equalization control with u ma 、u mb 、u mc Add, pass the result of addition through PWM, and get u ca 、u cb 、u cc .

6. The method for controlling a current-injected wideband impedance measurement device according to claim 1, wherein: According to u ca 、u cb 、u cc Perform broadband impedance measurement device control, including: According to u ca 、u cb 、u cc , obtain the duty cycle signal of the switch tube in the wide-band impedance measurement device and control the on and off of the switch tube.

7. A current injection broadband impedance measurement device control system, characterized in that: include: Conversion module, the collected u a 、u b 、u c and i a 、i b 、i c Convert to u respectively d 、u q and i d 、i q ; Among them, u a 、u b 、u c is the three-phase voltage at the grid connection point of the broadband impedance measurement device, i a 、i b 、i c is the three-phase current output by the broadband impedance measurement device, u d 、u q They are u in the rotating coordinate system a 、u b 、u c The d-axis component and q-axis component of i d 、i q They are respectively i in the rotating coordinate system a 、i b 、i c The d-axis component and q-axis component of Voltage outer loop control module, for u dc 、u dc_ref 、i a 、i b 、i c 、i a_ref 、i b_ref 、i c_ref Perform voltage outer loop control to obtain i d_ref ; Among them, u dc is the DC side voltage in the broadband impedance measurement device, u dc_ref is the preset DC side voltage reference value, i a_ref 、i b_ref 、i c_ref is the preset output current reference value, i d_ref is the d-axis component of the current inner loop reference value; Current inner loop control module, i d_ref 、i q_ref 、i d 、i q Perform current inner loop control to obtain u d1 、u q1 ; Among them, u d1 、u q1 are the d-axis component and q-axis component of the inner loop control voltage, i q_ref is the preset current inner loop reference value q-axis component; Voltage feedforward control module, for u d1 、u q1 、i d_ref 、i q_ref 、u d 、u q Perform voltage feedforward control to obtain u d3 、u q3 ; Among them, u d3 、u q3 are the d-axis component and q-axis component of the three-phase control voltage in the rotating coordinate system respectively; Carrier modulation module, for u d3 、u q3 Carrier modulation is performed to obtain u ca 、u cb 、u cc ; Among them, u ca 、u cb 、u cc Three-phase control voltage for the broadband impedance measuring device; Device control module, according to u ca 、u cb 、u cc Conduct broadband impedance measurement device control; The above d1 、u q1 、i d_ref 、i q_ref 、u d 、u q Perform voltage feedforward control to obtain u d3 、u q3 ,include: will i d_ref The product of R, i q_ref The opposite of the product of wL, u d 、u d1 Add and get u d3 ; Where R is the filter resistance, L is the filter inductance, and w is the fundamental angular velocity; will i q_ref The product of R, i d_ref The product of wL and u q 、u q1 Add and get u q3 .

8. A computer-readable storage medium storing one or more programs, characterized in that: The one or more programs include instructions that, when executed by a computing device, cause the computing device to perform any one of the methods according to claims 1 to 6.

9. A computing device, characterized in that include: One or more processors, one or more memories, and one or more programs, wherein the one or more programs are stored in the one or more memories and configured to be executed by the one or more processors, the one or more programs comprising instructions for performing any of the methods according to claims 1 to 6.

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