59 results about "Matrix converters" patented technology

The single-phase bidirectional single-stage isolation matrix converter comprises a pre-stage circuit and a post-stage circuit, and the pre-stage circuit comprises an LC filter on the power grid side, a pre-stage single-phase matrix conversion circuit and an LLC resonance circuit with a high-frequency transformer; the post-stage circuit comprises a post-stage conversion circuit and an output filter capacitor; the front-stage single-phase matrix conversion circuit comprises four bidirectional switch assemblies of a full-bridge structure. Each bidirectional switch assembly comprises two unidirectional controllable MOS tubes which are reversely connected in series, one end of each bidirectional switch assembly is connected to an L line or an N line of a power grid, and the other end of each bidirectional switch assembly is connected to the LLC resonance circuit. The rear-stage conversion circuit comprises a bidirectional MOS (Metal Oxide Semiconductor) tube bridge circuit and three high-frequency transformer secondary windings which are in triangular connection or star connection; and two end points of each secondary winding are respectively connected to the upper MOS tube and the lower MOS tube of the corresponding bridge arm and then are connected to output positive and negative ends. The converter has the advantages of high power density, low current harmonic, high power factor and the like, and is small in size, strong in anti-interference capability, wide in buck-boost range, and safe and reliable in commutation.

The invention provides a current stress optimization method and system for an isolated bidirectional three-phase energy storage converter, and relates to the technical field of power conversion. Firstly, Fourier series analysis is carried out on primary and secondary side voltages of a high-frequency transformer, and leakage inductance current and active power are calculated accordingly; carrying out per-unit processing on the active power and the square of the primary side current, and obtaining the active power and the square of the peak current under the fundamental component based on a per-unit processing result; then, with the minimum square of the peak current as an optimization target and the transmission power under the fundamental component as a constraint, constructing and solving a current stress optimization model so as to obtain an optimal matrix converter parameter; and finally, performing current stress optimization control based on the optimal parameters to reduce the current stress. According to the method, the current stress is remarkably reduced while the set transmission power requirement is met, the direct current side dynamic response is improved, and the converter performance is improved.

The present application relates to the technical field of power system relay protection, and particularly relates to a kind of offshore wind power through flexible low-frequency transmission system sending out line protection method, offshore wind farm is connected with modular multi-level matrix converter after being sent out by low-frequency through booster transformer, and is incorporated into large power grid after being frequency converted by M3C. When M3C of offshore wind farm fails, negative sequence current suppression and positive sequence current limiting strategy are adopted for fault ride-through, and relay protection devices are installed at both ends of low-frequency sending out line and communicate. The current sampling values before and after the fault on both sides of the line are reconstructed in phase space, and the difference between the permutation entropies is used to construct a protection scheme, which overcomes the problem of sensitivity reduction of traditional current differential protection for sending out line, reduces the amount of data interaction, and reduces the pressure of protection communication and the requirement of data synchronization. It is not affected by the control strategy of wind turbine and modular multi-level matrix converter at both ends of the line, fault ride-through mode, transition resistance and fault location, and has high reliability and good speed.

The application belongs to the technical field of power electronics, and discloses a double-vector model-free predictive control method for a reduced matrix converter and a related device, the method comprising: obtaining the AC side voltage, DC side voltage and DC side reference voltage data of the reduced matrix converter at a target moment, and calculating the inner loop reference current; obtaining the AC side current and switch input side current of the reduced matrix converter at an adjacent moment, calculating the system gain and system concentrated disturbance of the reduced matrix converter at the target moment, and combining the DC side current of the reduced matrix converter at the target moment to calculate the AC side current at the next moment corresponding to each switch state; and according to the inner loop reference current and the AC side current at the next moment, calculating the action time corresponding to the optimal vector and the suboptimal vector and determining the wave emission mode. The application realizes the model-free predictive control of the RMC, improves the anti-interference of the RMC, and reduces the AC side current ripple through the double-vector fixed-frequency control.

The invention discloses a modular multilevel matrix converter layered architecture device and a control method thereof. The invention discloses a layered architecture device. Comprising a three-phase AC input system, a bridge arm circuit, a three-phase AC output system, a DSP controller circuit, an FPGA controller circuit, an isolation driving circuit, a protection circuit, a starting circuit, an input voltage and current sampling circuit, an output voltage and current sampling circuit, a bridge arm voltage sampling circuit, a bridge arm current sampling circuit, a sampling signal conditioning circuit and an observer. According to the invention, the observation of the capacitor voltage of the M3C bridge arm sub-module is realized by using the observer, the number of voltage sensors and sampling circuits is reduced, the reliability of the system is improved, and the hardware cost is reduced; the hierarchical control method enables the control program to be easy to modify, update and transplant, reduces the workload of developers, and improves the control real-time performance.

The invention provides a matrix converter low-frequency side outer ring reactive power control method and a related device, and the method comprises the steps: carrying out the matching processing based on the obtained operation scene data of the low-frequency side of a matrix converter, determining whether a reactive power control strategy is matched, and if the reactive power control strategy is matched, outputting a reactive power control strategy; if yes, performing coordinate conversion processing on three-phase voltage data and three-phase current data in the operation scene data to obtain voltage conversion data and current conversion data; calculating actual reactive power data based on the voltage conversion data and the current conversion data; performing deviation correction based on the actual reactive power and the obtained reactive power control target data to obtain a deviation correction signal, and performing feed-forward compensation on the reactive power control target data to obtain a feed-forward compensation signal; and performing fusion conversion processing on the feed-forward compensation signal and the deviation correction signal to obtain a control instruction signal, and adjusting the outer loop reactive power of the low-frequency side of the matrix converter based on the control instruction signal. The method improves the operation energy efficiency of the power system.

The invention belongs to the field of direct current transmission system control, and particularly relates to a positive and negative sequence PR modular multi-level matrix type converter circulation control method and a medium. The method comprises the following steps: decoupling a circulating current component from industrial frequency transformer valve side current, low frequency transformer valve side current and bridge arm current of the modular multilevel matrix converter (M3C); according to the phase sequence characteristics of the three-phase bridge arm current frequency, analyzing the current frequency phase sequence characteristics of a circulation component carried in the bridge arm current; according to the current frequency phase sequence characteristics of the circulation component, the circulation component current frequency is obtained, wherein the circulation component current frequency forms a non-single frequency doubled circulation frequency by a power frequency () and a low frequency (); and performing Park change with the sum as a rotation angle on the three-phase bridge arm current, respectively adjusting the three-phase bridge arm current by a PR controller with the sum as a resonant frequency, synthesizing a bridge arm circulating current component through a modulation coefficient and reverse Park change, and continuously iterating to eliminate the circulating current frequency. Therefore, the circulation component in the M3C is inhibited, and the problem of instability in the M3C is solved.

The invention discloses a unilateral matrix converter system for PMSM (permanent magnet synchronous motor) driving application. The unilateral matrix converter system comprises a three-phase input end, a unilateral matrix conversion module, a control module and an output end, the matrix transformation module is composed of a plurality of one-way IGBT power switches, switching is carried out between input phases through a time multiplexing strategy, and direct alternating current to alternating current energy transmission without an intermediate direct current link is achieved. The system adopts a most positive and negative phase selection algorithm and a V / f control strategy, and the output voltage and frequency are adjustable. Compared with a traditional AC-DC-AC system, the AC-DC-AC system does not need a high-capacity capacitor, is simple in structure and low in control complexity, has the energy conversion efficiency as high as 85-90%, has high reliability, light weight and modular expansion capability, and is suitable for aerospace and high-performance motor driving application.

An energy efficiency optimization control method for a single-stage isolation matrix converter is proposed. This method calculates the input current vector magnitude of a three-phase single-stage isolation matrix AC-DC converter, derives the duty cycle expression, minimizes the current stress in the three-phase single-stage isolation matrix AC-DC converter, achieves soft switching, derives the full-bridge phase shift angle expression based on the per-unit value of the input current, designs a single-loop voltage control circuit, does not sample the input current, achieves unity power factor, and keeps the input current sinusoidal.

The invention discloses a method for controlling a controlled impedance source of a modular multi-level matrix converter for low-frequency power transmission. According to the control method, on the basis of the idea of a controlled impedance source, the sub-module is equivalently designed to be a frequency division controlled impedance source, energy transfer between impedances is achieved, namely, a power frequency impedance source obtains energy from a power grid, a low frequency impedance source transmits power to a low frequency power transmission system, and therefore stable control over the capacitor voltage of the converter sub-module is guaranteed. And meanwhile, non-communication power frequency / low frequency grid-connected synchronization of the M3C system and self-synchronization among the sub-modules are realized by utilizing the passive synchronization characteristic of the controlled impedance source. The control structure is simple, the information flow of controller interaction and centralized communication can be obviously reduced, and expansion to more quantum modules is easy. According to the control method provided by the invention, the efficiency and safety of the flexible low-frequency power transmission system can be improved, and large-scale grid connection and frequency division power transmission of offshore wind power are realized.

The application discloses a kind of offshore low-frequency wind power transmission line longitudinal protection method and system, after fault occurs, the control strategy of permanent magnet direct drive wind generator net side converter and modular multilevel matrix converter is switched, protection device is collected negative sequence current on line two sides;Wavelet transform denoising is carried out to the negative sequence current collected on line two sides, and mode component is extracted in combination with variable mode decomposition;The energy of each mode component obtained is calculated, and the largest energy characteristic mode is selected;The Hilbert transform is carried out to the selected characteristic mode, and the negative sequence current envelope line is extracted;The slope of negative sequence current envelope line is fitted using least square method;The protection direction identification value of line two sides is determined according to the positive and negative of slope;The protection direction identification value of line two sides is transmitted to the opposite side, when logic criterion F =1 is judged as internal fault, otherwise as external fault, the application meets power grid specification, and the noise resistance is strong, internal fault is sensitive action, and the safety of system is guaranteed.

The application provides a matrix converter system and a control method thereof. The matrix converter system comprises a first output port and a second output port, at least two phases, N converter valve bridge arms, Q first magnetic elements, the i-th first magnetic element comprises N first ports, M second ports, the N first ports of the i-th first magnetic element are connected in series with one end of the N converter valve bridge arms respectively, the other end of the N converter valve bridge arms is connected with any one phase of the first output port respectively, and the other end of at least one converter valve bridge arm is connected with a phase of the first output port which is different from the phase of the first output port connected with the other end of the remaining converter valve bridge arms, and the M second ports of the i-th first magnetic element are connected with any one phase of the second output port respectively, and at least one second port is connected with a phase of the second output port which is different from the phase of the second output port connected with the remaining second ports. i i i i i i ​​​​​​

The application discloses a C-shaped iron core combined rotary loose coupling transformer, which comprises a fixed assembly and a rotary assembly. The fixed assembly comprises a fixed iron core, first and second fixed windings and a fixed side circuit; the longitudinal section of the fixed iron core is in the shape of a C letter, and the fixed iron core comprises a first fixed iron core, a second fixed iron core and a third fixed iron core; the rotary assembly comprises a rotary magnetic core, a rotary shaft, a rotary bearing, a rotary clamping groove, first and second radial rotary rings, first and second rotary windings and a rotating side circuit; the fixed iron core surrounds the outer periphery of the rotary shaft in the radial direction, and the fixed iron core and the rotary shaft are fixed by the rotary bearing; the first fixed winding and the second fixed winding are connected in series, and the first rotary winding and the second rotary winding are also connected in series. The C-shaped iron core combined rotary loose coupling transformer designed by the application reduces the axial size and weight, improves the power transmission capacity, and first connects the rotating side circuit with a matrix converter.

This application discloses a method and device for locating faults inside and outside the converter zone of a modular multilevel matrix converter, relating to the field of power electronics. The method includes: acquiring electrical quantity data of the converter zone; calculating the average capacitor voltage of each sub-converter on the power frequency side and low frequency side based on the sub-module capacitor voltage; determining whether a short-circuit ground fault has occurred inside / outside the converter zone based on the zero-sequence components of the power frequency AC voltage and the low frequency AC voltage; if not, determining whether a bridge arm short-circuit fault has occurred based on the sub-module capacitor voltage; if no bridge arm short-circuit fault has occurred, determining whether a phase-to-phase short-circuit fault has occurred inside / outside the converter zone based on the average capacitor voltage of each sub-converter on the power frequency side and low frequency side and the direction of the bridge arm current; if no fault has occurred, determining whether an open-circuit fault has occurred or whether the system is in normal operation based on the sub-module capacitor voltage. This application can distinguish between faults inside and outside the converter zone of a modular multilevel matrix converter, saving fault repair time.

The application discloses a control method for balancing capacitor voltages between bridge arms of a modular multilevel matrix converter, which comprises the following steps: defining relevant electrical quantities related to the modular multilevel matrix converter; defining positive and negative sequence cyclic component forms of low and high frequencies of the modular multilevel matrix converter and control strategies of the cyclic components based on the relevant electrical quantities; adding module capacitor voltages of nine bridge arms of the modular multilevel matrix converter and filtering the added voltages by using a low-pass filter to obtain direct current components of the capacitor voltages of the nine bridge arms; performing double alpha beta 0 transformation on the direct current components of the capacitor voltages of the nine bridge arms to obtain eight u Cαβ0 / αβ0 components; controlling the eight u Cαβ0 / αβ0 components based on the positive and negative sequence cyclic component forms of low and high frequencies and the control strategies of the cyclic components to obtain four groups of sequence cyclic components of the nine bridge arms, and then adding the four groups of sequence cyclic components to obtain voltage modulation waveforms of the cyclic components of the nine bridge arms.

The invention discloses a harmonic control method based on an isolated matrix converter, and relates to the technical field of power electronics, and the method comprises the steps: carrying out the phase-locked loop and coordinate transformation processing of a sampled network-side voltage and a sampled network-side current, and obtaining the network-side input quantity of a harmonic controller; sampling a direct current side voltage and a direct current side current as direct current side input quantities of the harmonic controller; based on the grid side input quantity and the direct current side input quantity, the reference current and the reference reactive power are combined, a harmonic controller is used for compensating power deviation, and the duty ratio and the phase shift angle are obtained; based on the duty ratio and the phase shift angle, driving signals of all switching tubes in the matrix circuit are obtained through a pulse width modulation controller, and driving signals of all switching tubes of a full bridge are obtained through a phase shift controller. According to the invention, through double-loop control of the DC side current outer loop and the power inner loop, the current waveform of the AC side is optimized, and when the power fluctuates, the control variable can be rapidly adjusted, and the harmonic content of the AC side is reduced.

This invention provides an explosion-proof and automatically cooling low-voltage power supply device, belonging to the field of power supply equipment technology. It includes mechanical and electrical components. The mechanical component includes a power supply main body, while the electrical component includes a multi-functional power analysis module, a data acquisition module, a matrix converter, an isolation transformer, an intelligent power switch module, and an energy storage power supply module, all housed within the power supply main body. The power supply main body has a dividing vertical plate that separates its interior into a first installation area and a second installation area. When the temperature rises, a thermistor triggers the power supply to operate. The power supply supplies power to a cooling fan for heat dissipation and simultaneously opens an explosion-proof valve. This design effectively prevents the risk of explosion due to excessive temperature and, in the event of an explosion, inhibits its propagation. An explosion-proof heat dissipation component is installed in the second installation area to facilitate overall heat dissipation.

The invention provides a bridge arm capacitor voltage control method, a bridge arm capacitor voltage control system and a storage medium. The bridge arm capacitor voltage control method comprises the following steps of performing coordinate conversion processing on an acquired bridge arm capacitor voltage instantaneous value of a matrix converter to obtain a voltage unbalance initial component; classifying the voltage unbalance initial components according to frequency characteristics, and configuring wave filtering parameters based on the voltage unbalance initial components with different frequency characteristics to perform ripple suppression processing to obtain voltage unbalance first components; inputting the voltage imbalance first component into a PI controller to generate a branch bridge arm power reference value; adjusting a branch bridge arm power reference value based on a phase transformation matrix of the matrix converter to generate a basic circulating current component and a ripple compensation circulating current component; performing fusion correction on the basic circulating current component and the ripple compensation circulating current component based on actual operation data to obtain a circulating current control instruction; and controlling the bridge arm capacitor voltage of the matrix converter based on the annular control instruction signal. According to the method, ripple accumulation is effectively avoided, and power switch tube loss is reduced.

The application relates to the field of power electronics, in particular to a hybrid commutation method and system. The hybrid commutation method is used for the commutation of a current source type matrix converter, and the method comprises the following steps: using a 2 / 3 PWM modulation mode to alternately control the turn-on and turn-off of the upper switch tube or the lower switch tube of any two phases of A phase, B phase and C phase of the current source type matrix converter, and meanwhile making the lower switch tube or the upper switch tube of the remaining one phase in a clamping state; obtaining the voltage difference between the upper switch tube or the lower switch tube of the any two phases; when the voltage difference is greater than a preset voltage threshold, using a voltage type commutation mode to control the switching sequence of the upper switch tube or the lower switch tube of the any two phases. Sensor-free, reduced hardware cost and complexity: the method replaces real-time sensor detection through sector prediction and current change rule calculation, and high-bandwidth current sensors and precise voltage detection circuits are omitted, so that the system hardware cost is reduced.

The invention provides a method and a device for acquiring harmonic equivalent impedance of a modular multilevel matrix converter. The method comprises the following steps: defining positive sequence impedance and negative sequence impedance of an M3C in a three-phase symmetric operation state; applying a voltage disturbance in a set range of an M3C steady-state working point, and calculating a bridge arm reference voltage disturbance harmonic wave caused by the voltage disturbance in a dq coordinate system; obtaining a phasor form of a bridge arm reference voltage disturbance harmonic wave under an abc coordinate system through coordinate transformation; establishing a KCL equation for a bridge arm connecting the power frequency side and the low frequency side and carrying out linearization processing to obtain a disturbance voltage generated after the disturbance current is responded by the controller; simplifying a bridge arm voltage and current relation based on the disturbance voltage to obtain a unified disturbance voltage vector and disturbance current expression; and on the basis of the disturbance voltage vector, the current expression, the positive sequence impedance and the negative sequence impedance, the M3C positive sequence impedance seen from the power frequency side and the low frequency side is obtained through derivation by adopting per unit values.

The invention relates to the technical field of rectifiers, and provides an active clamping three-phase high-frequency link matrix rectifier and a pulse width modulation method thereof.The active clamping three-phase high-frequency link matrix rectifier comprises a three-phase alternating-current power supply, an LC input filter, a matrix converter, a high-frequency transformer, an uncontrolled rectifier bridge, an output filter and a load which are connected in sequence; an active clamping circuit is connected in parallel between the uncontrolled rectifier bridge and the output filter; each of the upper and lower bridge arms of each phase of the matrix converter comprises two switching tubes which are reversely connected in series. Based on the topology, the resonance process characteristics of the parasitic capacitance of the secondary side diode and the leakage inductance of the transformer are combined, and the high voltage stress generated by the leakage inductance of the transformer and the oscillation of the parasitic capacitance of the secondary side diode is suppressed by driving the auxiliary switch Saux on the premise of ensuring the output quality.

The invention discloses an M3C bridge arm voltage output capability determination method, system and device and a medium, and belongs to the technical field of power electronics, a single bridge arm loop model of a modular multi-level matrix converter M3C is established, a single bridge arm loop voltage expression is deduced, and a single bridge arm is formed by connecting a plurality of cascaded full bridge sub-modules and a bridge arm inductor in series; the method comprises the following steps: splitting a single-bridge arm loop voltage into a power frequency component and a low frequency component by neglecting a circulating current influence, and respectively establishing a power frequency side three-phase simplified loop and a low frequency side three-phase simplified loop; determining a power frequency side no-load modulation degree based on the voltage transmission characteristics of the power frequency side three-phase simplified loop; determining a low-frequency side no-load modulation degree based on the voltage transmission characteristics of the low-frequency side three-phase simplified loop; and obtaining a power frequency side phase voltage peak value and a low frequency side phase voltage peak value, and calculating the voltage output capability of the M3C bridge arm according to the power frequency side no-load modulation degree and the low frequency side no-load modulation degree.

The invention discloses a neural network prediction control method for a modular multilevel matrix converter, and belongs to the field of power electronics. The M3C is a power electronic topology for realizing direct alternating current-alternating current electric energy conversion, and has the advantages of modularization, flexible control, high electric energy quality and the like. A traditional FCS-MPC needs to traverse all possible switch state combinations in a control period, huge calculation burden is caused, meanwhile, the control precision of the FCS-MPC depends on the accuracy of a mathematical model, and robustness is poor. The invention provides a neural network predictive control method for M3C, and the method comprises the steps: collecting the input and output data of an FCS-MPC controller under different working conditions, carrying out the offline training of a neural network through the collected data, replacing the FCS-MPC with the trained network, and carrying out the real-time control, and also provides a delay compensation scheme of the method. According to the method, the online calculation burden of the digital controller is greatly reduced, and disturbance of M3C system parameters is introduced in the training process of the neural network, so that the neural network prediction controller has higher adaptability to parameter changes, and the robustness of the control system is further improved.

The invention belongs to the technical field of power electronics, and discloses a double-vector model-free predictive control method and related device for a simplified matrix converter, and the method comprises the steps: obtaining the AC side voltage, DC side voltage and DC side reference voltage data of the simplified matrix converter at a target moment, and calculating an inner ring reference current; obtaining the alternating current side current and the switch input side current of the simplified matrix converter at adjacent moments, calculating the system gain and the system concentrated disturbance of the simplified matrix converter at the target moment, and calculating the alternating current side current of the next moment corresponding to each switch state in combination with the obtained direct current side current of the simplified matrix converter at the target moment; according to the inner ring reference current and the alternating current side current at the next moment, action time corresponding to the optimal vector and the suboptimal vector is calculated, and a wave sending mode is determined. According to the method, RMC model-free predictive control is realized, the anti-interference performance of the RMC is improved, and the alternating current side current ripples are reduced through double-vector fixed-frequency control.

The invention provides a single-phase high-frequency rectifier with a clamping circuit and a modulation method thereof, and relates to the field of rectifiers, and the single-phase high-frequency rectifier comprises a matrix converter, an active clamping circuit and a full-bridge rectifier. The matrix converter is used for converting a power frequency alternating current signal into a high-frequency alternating current signal; the active clamping circuit is a full-bridge circuit, and the active clamping circuit is used for eliminating leakage inductance of the high-frequency transformer and resonance voltage overshoot of a parasitic capacitor of a switching tube and is matched with the matrix converter to complete safe commutation of inductive current; the active clamping circuit is connected in parallel with the output of the matrix converter; the full-bridge rectifier comprises four MOSFETs (Metal-Oxide-Semiconductor Field Effect Transistors), the input end of the full-bridge rectifier is connected with the preceding-stage matrix converter and the active clamping circuit through the high-frequency transformer, and the output end of the full-bridge rectifier is connected with the filter capacitor and the resistor in parallel; the full-bridge rectifier is used for converting the high-frequency alternating-current signal into a direct-current signal. According to the technical scheme, the problems of voltage spike and resonance existing in a rectifier in the prior art are solved.

This application provides an isolated matrix converter system and its control method. The isolated matrix converter system includes: a first output port; a second output port; at least one converter valve bridge arm; and at least one multi-winding transformer. The multi-winding transformer includes: a primary winding, a first secondary winding, and a second secondary winding. The primary winding is connected to the converter valve bridge arm; the first secondary winding is connected to the first output port; and the second secondary winding is connected to the second output port. This application optimizes the configuration of magnetic components in the matrix converter system, rationally configures the bridge arm combination, and optimizes the operating state of the magnetic components. While reducing the magnetic saturation of magnetic devices such as bridge arm reactance or transformers, it integrates the transformers on both sides of the matrix converter system, reducing the system's footprint.

The invention relates to an active AC / DC converter (1) which is designed to generate a variably specifiable DC voltage and to output same at a DC voltage output (5). The AC / DC converter (1) is equipped with: an AC input (4) for the connection of a plurality of AC phases (usually three AC phases); a transformer (7); a matrix converter (6) connected downstream of the AC input (4); and a rectifier output stage (8). The matrix converter (6) is connected or connectable to each AC phase of the plurality of AC phases via a plurality of converter inputs (21) and is designed to generate, from an AC voltage having a first frequency applied to the AC input (4), an alternating current having a second frequency different from the first frequency and to output same via a plurality of converter outputs (9) to a plurality of primary-side connections of the transformer (7). The rectifier output stage (8) is connected on the input side to a secondary-side connection of the transformer (7) and on the output side to the DC voltage output (5) and is designed to convert an output AC voltage of the transformer (7) into the variably specifiable DC voltage.

The application discloses a kind of matrix converter filter parameter optimization method, it is related to matrix converter control technical field, including obtaining the value of filter inductance and filter capacitance according to input side LC filter constraint condition and element easy purchase;The actual content of different harmonic currents in input current near resonance point under the condition of undamped resistance is obtained by simulation analysis;The upper limit of current content of main harmonic near resonance point is obtained by standard IEC6100-3-2, and the calculated value of damping resistance for suppressing different harmonic currents is calculated;This is compared with common resistance value system table, and the actual value of damping resistance is obtained;The input performance of matrix converter under the condition of different damping resistance actual value is analyzed to obtain the actual value of damping resistance under the optimal input performance.The application effectively suppresses the content of harmonic current near input resonance point, considers the attenuation effect of high frequency band harmonic, reduces control difficulty and system cost, and greatly improves input stability.

The application discloses a kind of offshore wind power sending-out scene parameter optimization design method and equipment, belong to flexible low-frequency power transmission technical field, by constructing "initial parameter determination-preliminary electrical design-bridge arm reactance and submodule capacitance calculation-simulation check-closed loop iteration optimization" annular verification process, traditional static parameter calculation is combined with the depth of system dynamic electromagnetic transient simulation.This method can systematically verify and optimize the key parameters such as bridge arm voltage, inductance, submodule capacitance of modular multilevel matrix converter (M3C), ensure that the electrical stress of IGBT, capacitor and other core devices under rated and transient operating conditions is within the safety margin, while avoiding the increase in cost due to excessive reserve margin. Through iterative adjustment, the optimal balance between reliability, economy and performance is finally achieved in parameter design, which significantly improves the scientificity and engineering practicability of offshore wind power low-frequency sending-out system design.