129 results about "Matrix converters" patented technology

A direct current (DC) fast charger for charging a battery of an electric vehicle (EV) includes a primary circuit having seven bidirectional switches electrically linked to a primary wire of a transformer and configured to receive an alternating current (AC) voltage; and a secondary circuit comprising a plurality of diodes arranged to rectify the AC voltage into a DC voltage, electrically linked to the secondary leads of the transformer such that the DC fast charger unidirectionally converts the AC voltage received at the primary circuit into the DC voltage output by the secondary circuit.

An operation accelerator, a processing method, and a related device, the operation accelerator including a first memory configured to store an input dataset, a matrix converter configured to perform reading M row vectors from the input dataset, generating a first instruction, and sending the M row vectors and the first instruction to a second memory configured to perform, according to the first instruction, preprocessing on the M row vectors to obtain n row vectors, and storing the n row vectors, where the n row vectors include the M row vectors and (n−M) padding row vectors, the n row vectors are N row vectors in a target matrix, and a storage sequence of the n row vectors in the second memory is consistent with a sequence of the N row vectors in the target matrix.

The invention discloses a common-mode electromagnetic interference modeling and suppression method for a matrix converter, and the method comprehensively considers high-frequency parameters and topological characteristics, builds a conduction CM EMI equivalent circuit model of the matrix converter, completes the impedance network fitting of key elements and the extraction of high-frequency parasitic parameters, and achieves the modeling and suppression of the common-mode electromagnetic interference of the matrix converter. The precision of the CM EMI model of the matrix converter is improved, and the analysis of the CM EMI characteristics of the matrix converter is simplified. According to the common-mode electromagnetic interference suppression method for the matrix converter, CM EMI characteristics of the matrix converter are analyzed, a low-attenuation loop in the converter is constructed by adopting a method of combining a neutral line leading-back type structure and increasing output filter capacitor neutral-point-to-ground parasitic capacitance, the propagation proportion of noise in a linear impedance stabilization network measurement branch is reduced, and the measurement accuracy of the common-mode electromagnetic interference suppression method for the matrix converter is improved. And effective suppression of low-cost CM EMI noise is realized on the premise of not depending on an input EMI filter.

The invention discloses a high-precision voltage regulating system of a power frequency no-partial-discharge test transformer, and the system comprises a heterogeneous multi-stage power module which is formed by connecting an H-bridge unit group and a matrix converter in parallel, the H-bridge unit group outputs a fundamental voltage component, and the matrix converter compensates a high-frequency harmonic component; the multi-physics field digital twinning unit integrates an electromagnetic field solver, a thermodynamic model and a mechanical deformation simulation module and predicts the multi-physics field coupling state of the insulation system in real time; the dynamic impedance matching network comprises an adjustable inductor array and a digital capacitor bank, and automatically adjusts filtering parameters according to a load impedance measurement value; and the control module is used for deploying a deep learning model and is used for optimizing a modulation strategy and a protection threshold on line. According to the method, the voltage regulation precision and the waveform purity can be improved, the stability under the wide-range working condition is guaranteed, the breakdown hidden danger is recognized in advance through multi-physics field coupling simulation, and partial discharge development is restrained from the source.

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 present invention belongs to the technical field of matrix converters, and discloses a three-phase four-leg three-level direct matrix converter and an SVPWM modulation method. The topology consists of 24 bidirectional switches and 8 flying capacitors. Each of the four legs A, B, C, and N includes 9 output switching states and 6 output voltages. There are a total of 6561 switching states, and the output phase line voltages altogether include six output voltages. The present invention proposes a novel SVPWM modulation method. This method mainly transforms the control of the output voltage from the conventional αβ coordinate system to the abc coordinate system, while the input current is still modulated separately in the αβ coordinate system. The biggest advantage of using the abc coordinate system is that through coordinate translation, the three-level modulation can be simplified to two-level modulation, greatly reducing the increase in algorithm complexity caused by the increase in the number of levels.

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 invention discloses a three-phase energy storage converter dynamic parameter modulation method and a related device thereof, and the method comprises the steps: configuring a modulation strategy of a grid side 3-1MC matrix converter as a current space vector modulation strategy, configuring a modulation strategy of a DC side H bridge as a phase shift modulation strategy, introducing a modulation duty ratio coefficient # imgabs0 # as a modulation parameter, and carrying out the phase shift modulation of the DC side H bridge; the modulation parameters are reduced to modulate a duty ratio coefficient # imgabs 1 # and an input reference current phase # imgabs 2 #, and the technical problems that in an existing modulation method of the AC-DC matrix converter, the modulation parameters are too many, all the parameters are difficult to coordinate through closed-loop control, no parameter can be used for closed-loop control, and meanwhile coordination control over the primary side and the secondary side is difficult to achieve are solved. On the basis, the waveform of a switching signal of the grid-side 3-1MC matrix converter is improved, so that during voltage commutation and current commutation of the grid-side 3-1MC matrix converter, power switch tubes connected in parallel with body diodes with opposite current directions in the grid-side 3-1MC matrix converter are kept on, and the soft switching characteristic of the power switch tubes is realized.

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.

An image restoration processor includes an image receiver, a matrix converter, a framework memory, a modifier, a matrix decomposer, and an image reconstructor. The image receiver receives one or more degraded images. The matrix converter reshapes image data of the one or more degraded images into one or more target matrices. The framework memory stores a framework for generating one or more sparsity-inducing regularizers. The modifier reads the framework memory and applies the framework to modify an M-estimator and accordingly output a hybrid M-estimator as well as the corresponding sparse regularizer. The matrix decomposer receives the one or more target matrices and the sparse regularizer and to apply the sparse regularizer to RPCA via decomposing one of the one or more target matrices into a sum of low-rank and sparse matrices. The image reconstructor integrates outcomes of decomposition from the matrix decomposer to form one or more recovered images.

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 present invention discloses a current-source high-frequency link matrix inverter topology with soft switching, comprising a sequentially connected power supply network, a current-source H-bridge, a series resonant tank, a high-frequency transformer, a matrix converter, a CL filter, and a load. The present invention uses series resonance to match the leakage inductance current of the high-frequency transformer with the DC-side input current, thereby avoiding large voltage spikes on the primary side of the high-frequency transformer and achieving zero-current switching of the current-source H-bridge. The present invention is also well-suited for high-frequency transformers with large leakage inductance. Furthermore, the proposed decoupling-based SPWM and SVM modulation methods for current-source matrix inverters feature mixed high- and low-frequency modulation, enabling safe commutation, effectively reducing the switching frequency of the matrix converter, and providing soft switching conditions for all switches in the matrix converter.

A method of carrier-based modulation with a dual gate bidirectional switch includes the steps of receiving a sine triangle pulse width modulation (PWM) signal; converting the received sine triangle PWM signal from a voltage source inverter (VSI) input to a current source inverter (CSI) output involving vector matching; converting the CSI output to internal model control (IMG) signal pulses; generating a PWM signal for each dual gate bidirectional switches based on the IMG signal pulses; generating two gate signals for each dual gate bidirectional switch; and selectively applying a phase shift or delay between the gate signals applied to a high side of the dual gate bidirectional switch relative to a low side of the dual gate bidirectional switch.

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 provides a modular multi-level matrix converter topology of a hybrid topology and a modulation method. The modular multi-level matrix converter topology comprises nine bridge arm reactors and nine low-frequency bridge arms, each phase of the low-frequency alternating-current system is respectively connected with three bridge arm reactors in series, the three bridge arm reactors after series connection are respectively connected with three low-frequency bridge arms in series, and the three low-frequency bridge arms after series connection are correspondingly connected with a power-frequency alternating-current power grid. By adopting the hybrid topology, the three-level bridge arm bears part of voltage, the number of cascaded full-bridge modules of the MMC bridge arm is reduced, the equipment cost is further reduced, the problem of high cost of a flexible direct current converter valve is solved, meanwhile, the use amount of power devices is reduced, and the defect that the modular matrix converter has more topological power devices is overcome. According to the modulation method, the mode that the three-level bridge arm and the MMC bridge arm are modulated respectively is adopted, the modulation method is simplified, and the modulation method is easy to implement.

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.

The invention provides a sparse modular multilevel matrix converter topology, a design method and a control method. The topology has three-phase symmetry of an input side and an output side. The design method aims at reserving the conventional M3C function and performance and reducing the cost, and comprises the following steps: setting the input side alternating current frequency and the output side alternating current frequency of a matrix converter to be in an integer frequency division relationship; through a control mode of phase coordination on two sides, the utilization rate of direct-current voltage is improved, and the modulation wave amplitude of each bridge arm is reduced; and determining that the number of the bridge arm sub-modules is less than that of the conventional M3C based on the modulation wave amplitude. Through the phase coordination technology, the number of the bridge arm sub-modules is reduced on the basis of reserving the conventional M3C function and performance, so that the cost is reduced, and the operation efficiency is improved to a certain extent.

The present application provides a practical evaluation method and device for transient overvoltage of a new energy low-frequency collection system. The purpose of the present application is to ensure the safe and stable operation of the system by calculating accurate transient overvoltages. Among them, the practical evaluation method for transient overvoltage of a new energy low-frequency collection system includes using the method of equivalent voltage source to determine the modular multilevel matrix converter in the new energy low-frequency collection system; obtaining the voltage, current, power, and short-circuit ratio of the new energy low-frequency collection system and the modular multilevel matrix converter, and calculating the voltage drop component caused by resistance and the voltage drop component caused by reactance based on the obtained data; determining the relationship between the voltage of the low-frequency side AC bus and the voltage of the sending-end unit; and using the voltage drop component caused by resistance, the voltage drop component caused by reactance, the relationship, and the short-circuit ratio to calculate the transient overvoltage.

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.

A direct current (DC) fast charger for charging a battery of an electric vehicle (EV) includes a primary circuit having nine switches, electrically linked to a primary wire of a transformer, and configured to receive three-phase alternating current (AC) power and increase a frequency of the AC power; and a secondary circuit comprising six switches or diodes arranged to rectify the AC voltage into DC power, the secondary circuit being electrically linked to the secondary leads of the transformer.

The present application discloses an isolated matrix converter and control method. The converter includes: a bidirectional switch module, a transformer, a resonant inductor, a resonant capacitor, and a bridge arm capacitor. The bidirectional switch module and the bridge arm capacitor are connected in series to form the bridge arm of the converter, and each bridge arm of the converter includes at least one bidirectional switch module. The primary winding of the transformer is connected in series with the resonant inductor and the resonant capacitor, and then connected to the two ends of the bridge arm of the converter. The bidirectional switch module includes: a clamping capacitor and a bidirectional switch unit. The bidirectional switch unit forms the two bridge arms of the module, and the two ends of the clamping capacitor are connected to the two ends of the two bridge arms of the module. The clamping capacitor forms a clamping absorption circuit with the two upper bridge arms or the two lower bridge arms of the two bridge arms. The bidirectional switch unit includes at least two controllable switching transistors. The clamping capacitor suppresses voltage spikes generated when the switching transistors in the bidirectional switch module are activated. This protects the switching transistors, and further protects the safety of the entire converter, thereby improving the reliability of the converter.

The invention discloses a three-phase single-stage isolation type matrix conversion circuit and a driving method, and the three-phase single-stage isolation type matrix conversion circuit generates a primary side control quantity and a secondary side control quantity based on a grid side electrical parameter and a DC side electrical parameter, and generates a primary side driving signal and a secondary side driving signal based on the primary side control quantity and the secondary side control quantity respectively. The primary side driving signal drives the three-phase matrix converter, and the secondary side driving signal controls the current of the transformer to be the minimum value in the power frequency period through the full-bridge inverter, so that the current of the transformer in the whole power frequency period can be minimized, and the conduction loss of a device and the loss of the transformer are reduced.

The utility model relates to a novel power spring device based on a matrix converter, and belongs to the technical field of power electronic converters and power springs. The structure mainly comprises an AC power grid, a line impedance, a voltage decomposition control module, an input LC filter, a matrix converter, an output LC filter, a non-critical load, an isolation transformer and a critical load. The matrix converter is a three-phase direct AC-AC matrix converter without a direct-current link, the matrix converter and an alternating-current power grid form a main circuit of the power spring, and a rectifying circuit and an electrolytic capacitor of the direct-current link are not needed. The novel power spring based on the matrix converter is connected in series with a non-critical load through an isolation transformer to form an intelligent load. And a voltage decomposition control strategy is adopted to realize the functions of stabilizing key load voltage, adjusting intelligent load power factors, reducing three-phase voltage unbalance degree, suppressing harmonic waves and the like.

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 provides a sparse modular multilevel matrix converter topology, a design method and a control method, and the topology has three-phase symmetry on the input and output sides. The design method is for the purpose of reserving the functions and performance of a conventional M3C and reducing the cost, and comprises the following steps: setting the input side and the output side AC frequency of the matrix converter as an integer frequency division relationship; improving the utilization rate of the DC voltage and reducing the modulation amplitude of each bridge arm through a two-side phase coordination control method; and determining the number of bridge arm sub-modules to be less than the number of bridge arm sub-modules of the conventional M3C based on the modulation amplitude. Through the phase coordination technology, the number of bridge arm sub-modules is reduced on the basis of reserving the functions and performance of the conventional M3C, so that the cost is reduced, and the operation efficiency is improved to a certain extent.

A stationary vehicle battery charger for charging vehicle batteries in battery electric vehicles (BEVs) includes a plurality of MOSFET modules, electrically connected to form a matrix converter, comprising a plurality of MOSFET switches, each MOSFET switch including a body diode and capable of bidirectional electrical current flow while the MOSFET switch is conductive, such that a MOSFET switch from a first MOSFET module and a MOSFET switch from a second, different MOSFET module are electrically coupled so that the body diodes prevent bidirectional current flow while the MOSFET switch from the first MOSFET module and the MOSFET switch from the second, different MOSFET module are non-conductive.