7485results about "Dc-ac conversion without reversal" patented technology

The present invention relates to the technical field of circuit control, and relates to a direct-current high-voltage generator regulation and control method and system based on intelligent feedback. A fuzzy control logic operation is performed on an output current flux value and an input voltage fluctuation factor of a load experimental object, so as to obtain the disturbance amplitude of a voltage fluctuation state for a current flux change trend; if a step-up transformer can execute a PID control technology by adjusting a transformation ratio, PID real-time adjustment parameters are calculated, and a crossover mutation operation of individuals is performed on the basis of a fitness function, so as to generate a first boost regulation and control scheme; and if the step-up transformer cannot execute the PID control technology by adjusting the transformation ratio, a calibrated state feedback controller is constructed on the basis of a state variable of the current step-up transformer and an adjustment signal output amplitude, so as to generate a second boost regulation and control scheme. The present invention achieves intelligent feedback regulation and control by independently analyzing components of direct-current high-voltage generators, improving the stability and accuracy of outputting high-voltage direct current.

The invention discloses a heat dissipation control method and system for stable operation of a photovoltaic inverter, and relates to the technical field of photovoltaic inverter control, and the method comprises the steps: collecting the multi-source data of heat dissipation equipment and elements in the use of the photovoltaic inverter; constructing a feature relation model and an LSTM neural network prediction model based on data acquisition; and through the constructed feature relation model and the LSTM neural network prediction model, analysis is carried out to compare different levels of heat dissipation power with the inverter efficiency improvement degree under different environment temperatures and power levels, a predicted temperature is formed, risk levels are divided, and the optimal heat dissipation level is determined. According to the method, the predicted temperature is graded by utilizing synchronous acquisition of multi-source data and constructing the feature relation model and the LSTM neural network prediction model, and the multi-mode heat dissipation strategy is formulated, so that the heat dissipation strategy is adaptively adjusted according to the state of the photovoltaic inverter to perform adaptive heat dissipation, and the heat dissipation efficiency is improved. And the heat dissipation effect of the photovoltaic inverter is further improved.

A passivity-based dual-mode integrated control method for a grid-connected inverter (GCI) is provided. In view of the insufficient robustness of the conventional single-mode GCI in a high-impedance and low-inertia weak grid, and the problem of wideband oscillation of the grid voltage and grid current or even system instability in nonlinear application scenarios such as grid structure / parameter variation, and plug-and-play of the inverter, the dual-mode integrated control method performs modeling on the GCI based on a port-controlled Hamiltonian (PCH) model, thereby obtaining integrated control with a weighted passivity-based feedback control law for the GCI based on a grid-following (GFL) mode and a grid-forming (GFM) mode. Based on the dual-mode integrated control method, the stable operation of the GCI in severe grid conditions with large fluctuation of the impedance, and desirable robustness of the GCI in nonlinear working scenarios can be ensured.

The invention relates to the technical field of inverter control, and provides an MBD-based reinforcement learning inverter control algorithm optimization method, which comprises the steps of S1, establishing a state space model of an inverter, designing a baseline controller of double-loop control, and constructing an MBD simulation platform containing multiple load models; s2, defining a state space of the 12-dimensional state vector, designing a continuous action space, and constructing an adaptive multi-target reward function; s3, training a control parameter optimization strategy by adopting an Actor-Critic algorithm architecture in combination with an experience playback mechanism and a hybrid exploration strategy; s4, establishing a security constraint mechanism of three-layer security protection, designing a fault detection and isolation strategy, realizing a closed-loop online learning strategy of pre-training-transfer learning-online fine tuning, and meanwhile, adopting a self-adaptive updating mechanism; and S5, verifying the optimization effect of the control algorithm through quantitative index evaluation, an experimental verification scheme and a real-time performance requirement test. And the upgrade of inverter control from model driving to data and model cooperative driving is realized.

The invention discloses a micro-grid power control method, system and device based on fuzzy modulation and a storage medium, and relates to the technical field of intelligent grid integration of a photovoltaic system and a micro-grid, and the method comprises the steps: firstly obtaining the real-time power data of a photovoltaic system, carrying out the control processing through fuzzy logic, and calculating a reference instruction; according to the reference instruction, hysteresis time is dynamically adjusted through modulation hysteresis control, and an inverter switching signal is generated; converting direct current into alternating current based on the switching signal and a power switching device, injecting the alternating current into the micro-grid, calculating active and reactive power reference values, ensuring that the system operates according to a unit power factor, and giving active power to the reference value; according to the method, the power control precision and adaptability of the micro-grid are improved, excessive switching of the inverter is avoided, loss is reduced, the service life is prolonged, power matching and stable transmission are achieved, reactive loss is reduced, bus voltage is stabilized, harmonic waves can be reduced, the electric energy quality is improved, and efficient and stable operation of the micro-grid is guaranteed.

The invention discloses an energy router inversion grid-connected port control method for optimizing a VSG, and the LADRC can dynamically compensate the influence of external disturbance on a system through the real-time observation of the state of the system, especially the monitoring of the disturbance and the change of the system, thereby enhancing the anti-interference capability of the system. When the load is suddenly changed or is externally disturbed, the LADRC can quickly identify the disturbance and generate an adaptive control signal, so that the inverter system is quickly recovered to a stable state. And the fuzzy adaptive PI controller adaptively adjusts the proportionality coefficient and the integral coefficient of the PI controller according to the real-time deviation and the change rate of the system, so that the parameters of the controller can be automatically adjusted according to the state of the system, and the limitation of a fixed parameter controller under complex working conditions is avoided. The self-adaptive adjustment not only improves the control precision, but also greatly improves the dynamic response speed of the system, so that the inverter can maintain an efficient and stable working state under the conditions of power grid disturbance, load change and the like.

The invention discloses a converter collaborative current limiting method based on adaptive virtual impedance and a power loop, and the method comprises the steps: firstly building an equivalent impedance model of a converter and a power grid, analyzing the steady-state and transient characteristics of fault current, and extracting key parameters for current limiting design; when it is detected that the voltage drop of the grid-connected point exceeds a threshold value, a self-adaptive virtual impedance link is automatically put into use, and virtual resistance and reactance values are dynamically calculated according to the variation amplitude of voltage or current, so that the virtual resistance and reactance values are proportionally adjusted along with the fault degree; and when the system voltage returns to normal, the virtual impedance automatically quits, and the control continuity is ensured. Then, the active and reactive power reference values are dynamically corrected according to the voltage drop depth, a power reference signal matched with the voltage amplitude is generated, it is guaranteed that power output does not exceed the limit, and the voltage supporting capacity is improved. Finally, real-time current-limiting control of the converter and stable operation of the system are realized on the premise of not switching the control mode through the synergistic effect of the virtual impedance ring and the power ring. The method has the advantages of being high in response speed, excellent in current limiting effect, good in control continuity and the like, and is suitable for fault current limiting and voltage support control of the grid-forming converter.

The invention discloses a grid-connected inverter control method based on second-order linear active disturbance rejection, and particularly relates to the field of grid-connected inverter control. Voltage and frequency error signals between the output side of the inverter and the power grid are obtained, a pre-synchronization control model is constructed, and voltage amplitude and frequency synchronization is achieved; a second-order linear active-disturbance-rejection controller is introduced in the frequency synchronization control process, an extended state observer is adopted to estimate the output frequency, the frequency change rate and a disturbance term, and a state error feedback control law is combined to generate a frequency regulation control quantity, so that accurate frequency control is realized; after grid connection, a dual-channel LADRC power regulation controller is constructed, and decoupling tracking control is carried out on active power and reactive power; meanwhile, on the basis of fast Fourier transform processing as a stable grid-connected state criterion, the method has the advantages of being high in control precision, high in anti-interference capability, good in current waveform quality, high in adaptability and the like, and is suitable for various grid-connected application scenes.

The invention provides a power grid connection disturbance observer feedback control method, which belongs to the technical field of power grid connection, and comprises the following steps: detecting power grid impedance parameters by using a multi-frequency harmonic injection technology, designing a disturbance observer algorithm to establish a state equation set, and constructing a nominal inverter model by using a low-pass filter; the total disturbance amount is estimated in real time by comparing the difference value between the actual current output and the nominal model output, a feedback control strategy is constructed, the disturbance estimation value serves as a feedforward compensation signal to be superposed to the current controller output, and disturbance components in different frequency ranges are processed in a classified mode according to disturbance types. A disturbance observer bandwidth parameter and a filter cut-off frequency are set, a disturbance estimation value is compensated to a current control loop in real time through a feedforward compensation signal to suppress the influence of power grid disturbance on the grid-connected current, and the technical problem that it is difficult to accurately estimate and compensate the influence of power grid disturbance on the grid-connected inverter in real time is solved.

The invention belongs to the technical field of power electronics of power supply or power distribution, and provides a control method of a three-phase four-wire inverter, a controller and an inversion control system. A first control component is generated by using a phase angle, an inversion side three-phase current sampling value and a proportional integral compensator; a second control component and a third control component are generated by using a power grid voltage angular frequency, a neutral line current sampling value, a repetitive controller and a proportional resonance controller, the three control components are combined to control an inverter power switch tube, a proportional integral compensator is still adopted, the algorithm is simple, parameters are easy to design, and the reliability is high. And meanwhile, a repetitive-proportional resonance (RC-PR) composite controller is utilized to realize suppression of neutral line fundamental wave and harmonic current, and the method has faster dynamic response to load abrupt change, so that optimization of dynamic performance and steady-state performance is realized.

An electric work vehicle includes a body, a travel device in the body, a motor to drive the travel device, an inverter to supply power to the motor, an electric component, a DC / DC converter to convert a voltage of power to be supplied to the electric component, a radiator to cool coolant, and a cooling path through which the coolant cooled by the radiator circulates through the motor, the inverter, and the DC / DC converter and returns to the radiator. The cooling path extends from the radiator, passes through the inverter, the motor, and the DC / DC converter in this order, and returns to the radiator.

This power conversion device includes a multilevel inverter which outputs multilevel voltages by adding / subtracting voltage of a sub inverter to / from output voltage of a main inverter. The multilevel inverter can switch between PWM operation in which plural pulses are outputted in each of positive voltage output and negative voltage output in one cycle and a pulse width is controlled, and one-pulse operation in which one pulse is outputted in each of positive voltage output and negative voltage output in one cycle, and has a current-split switching mode in which current flowing between a neutral point and the sub inverter flows through a first switch group and a second switch group provided to the main inverter and connected in parallel, in a case where the main inverter outputs zero voltage which is the potential of the neutral point, in the one-pulse operation.

The invention discloses a grid-connected inverter complementary sliding mode control method based on a cascade generalized proportional-integral observer, and the method comprises the steps: firstly building a mathematical model of a grid-connected inverter, and enabling the mathematical model to be used for the design of a controller; and a cascade generalized proportional integral observer is introduced to estimate the lumped disturbance of the hyper-local model so as to improve the anti-disturbance capability and the noise suppression capability of the system. By introducing the complementary sliding mode controller, compared with a traditional sliding mode, the position tracking error is reduced by half. By introducing the improved reaching law, a large reaching speed can be kept when the system state is far away from the sliding mode surface, and the sliding mode reaching speed is weakened when the system state approaches the sliding mode surface, so that the chattering phenomenon of the sliding mode is reduced. According to the control method, the coupling influence of the d axis and the q axis can be obviously inhibited, the harmonic content of the three-phase current is reduced, and stable operation of the grid-connected inverter is facilitated.

The invention belongs to the technical field of inverter control, and discloses a self-adaptive adjustment strategy for the inertia of a network-forming inverter in a large-disturbance scene of a parallel system, and the parallel system comprises the network-forming inverter and a network-following inverter, and is used for carrying out the self-adaptive adjustment of the inertia of the network-forming inverter in the large-disturbance scene. The method specifically comprises the following steps that a phase-locked loop is used for controlling the following grid type inverter, and following grid type dynamic influence factors of the following grid type inverter in a large disturbance scene are analyzed based on a following grid type inverter control block diagram; based on the following network type dynamic influence factors, constructing a following network type dynamic control equation used for describing the large disturbance process of the following network type inverter; according to the method, the inertia of the network-building type inverters is effectively adjusted in a large disturbance scene of the multi-inverter parallel system, the transient synchronization characteristic of the network-building type inverters in the multi-inverter parallel system is improved, the parallel system has more stable voltage and frequency support, and the stability of the whole system is further improved.

Assembly for supplying power to a rotating electric machine for driving a vehicle including at least one string of modules having first and second terminals. Each string includes at least one module having its tertiary and quaternary terminals connected to a first power supply bus and at least one module having its tertiary and quaternary terminals connected to a second power supply bus, the modules of each string being distributed in particular between modules having their tertiary and quaternary terminals connected to the first power supply bus and modules having their tertiary and quaternary terminals connected to the second power supply bus. At least one DC / DC converter of a module of each string is an isolated and reversible converter.

The invention discloses a photovoltaic power station multi-source inverter active power control method and system, and relates to the technical field of photovoltaic power station active power control, and the method comprises the steps: calculating the dynamic performance score of each inverter based on the response time, conversion efficiency and health degree data of a multi-source inverter of a target photovoltaic power station; dividing the multi-source inverter into a response group and a steady-state compensation group based on the dynamic performance score and the dynamic division threshold; based on a preset allocation proportion, allocating the scheduling power regulation quantity to the response group and the steady-state compensation group; monitoring the overall output power of the target photovoltaic power station in real time; if the overall output power does not reach the target power range within the preset time, the active power output proportion of the response group is adjusted based on the prediction model; and after the overall output power of the target photovoltaic power station reaches the target power range, starting steady-state power replacement. The technical problem that the prior art cannot adapt to real-time working condition changes is relieved.

The invention relates to an inverter control system, and the system comprises distributed intelligent nodes which are used for collecting sensor data of a target part, obtaining a fault signal, and simply controlling an inverter according to the sensor data; the intelligent control module is used for generating an optimal power control instruction to control the inverter and communicating with external equipment; the intelligent feedback regulation module is used for fusing the sensor data and obtaining an optimal control strategy to control the inverter; the intelligent energy interconnection and scheduling module is used for collecting information of distributed energy, obtaining a global optimal energy scheduling strategy according to the information of the distributed energy, and controlling the inverter according to the global optimal energy scheduling strategy; and the intelligent energy efficiency evaluation and optimization module is used for monitoring the inverter, obtaining and evaluating the energy efficiency level of the inverter, and optimizing the control parameters and the operation mode of the inverter according to the evaluation result. According to the invention, the performance and efficiency of the inverter can be improved.

The invention discloses an integration and optimization method of a multilayer circuit board in a photovoltaic inverter, and the method comprises at least seven layers of functional stacked structures which are an electromagnetic shielding layer, a power device layer, a first insulating dielectric layer, a control circuit layer, a second insulating dielectric layer, a heat dissipation substrate layer and a mechanical strengthening layer from top to bottom in sequence. Wherein the power device layer adopts a three-dimensional embedded packaging technology to integrate an IGBT module and a SiC MOSFET module, and a gate drive circuit of the power device layer is embedded into a first insulating dielectric layer in a coplanar waveguide structure; the heat dissipation substrate layer is provided with a micro-channel array with gradient apertures, and the inner wall of each micro-channel is subjected to anodic oxidation treatment to form an Al2O3 ceramic layer with the thickness of 20-50 microns.

The invention discloses a power equipment control method based on cloud edge collaboration and electronic equipment. The method comprises the following steps: receiving initial resonance waveform data corresponding to a plurality of inverters in power equipment sent by an edge server; based on the initial resonance waveform data corresponding to the plurality of inverters, determining the resonance frequency dynamic correlation strength between every two inverters in the plurality of inverters; generating a cooperative control parameter based on the resonant frequency dynamic correlation strength between every two inverters; and sending the cooperative control parameters to an edge server, so that the edge server determines real-time resonance fluctuation data corresponding to the plurality of inverters, calculates a resonance suppression compensation control signal based on the real-time resonance fluctuation data, and compensates the initial control signals corresponding to the plurality of inverters based on the resonance suppression compensation control signal. According to the invention, the technical problem that the compensation accuracy is low when resonance compensation is carried out on the inverter in the power equipment in the prior art is solved.

An electrical propulsion system comprises an inverter, an electrical motor assembly, an assembly, and a rotor position sensor. The inverter comprises a printed circuit board assembly (PCBA). The electrical motor assembly comprises a stator and a rotor. The assembly is configured to rotate a propeller and comprises a moving component and a stationary component. The rotor position sensor comprises at least one sensor coupled to the PCBA, and a magnet located on the moving component. The at least one sensor is configured to detect a magnetic field of the magnet through the stationary component.

The invention relates to the technical field of power system control, in particular to a direct-current capacitor self-synchronizing grid-connected control strategy method, system, equipment and medium, a direct-current capacitor energy dynamic model is established based on an actual energy balance relation, a direct-current voltage signal is acquired in real time, and a synchronous compensation signal is calculated based on the acquired direct-current voltage signal; performing phase compensation and gain adjustment on the synchronous compensation signal through a correction link based on the calculated synchronous compensation signal, adjusting the internal frequency of the inverter based on the synchronous compensation signal after phase compensation and gain adjustment, controlling the DC voltage through the internal frequency of the inverter, and establishing a self-synchronization control model; and based on the self-synchronization control model, establishing an adaptive control algorithm, generating a damping coefficient and a virtual inertia coefficient through the adaptive control algorithm, and dynamically adjusting control parameters according to the damping coefficient and the virtual inertia coefficient.

The invention relates to the technical field of power electronic converters, and discloses a grid-connected inverter multi-parameter online setting method, system and device and a medium. The method comprises the following steps: establishing a circuit simulation model of the grid-connected inverter; output currents of the grid-connected inverter under different power grid impedance working conditions are obtained through the circuit simulation model, and target control parameters of the grid-connected inverter under different power grid impedance working conditions are obtained through iterative search by adopting a particle swarm optimization algorithm through the circuit simulation model; performing off-line training on the parameter reasoning model through the output current of the grid-connected inverter under different power grid impedance working conditions and the target control parameter under the corresponding power grid impedance working condition; acquiring an output current of the grid-connected inverter in real time, and inputting the output current acquired in real time into the trained parameter reasoning model to obtain a corresponding target control parameter; and on-line setting is performed on the control parameters of the grid-connected inverter through the target control parameters output by the parameter reasoning model, so that rapid setting can be realized.

The invention discloses a current source type LCCL double-frequency resonance system and a parameter matching method thereof, which are suitable for synchronous double-frequency induction quenching of complex workpieces such as gears. The system is composed of two current type resonant inverters working at a low frequency and a high frequency respectively and a dual-frequency LCCL resonant cavity, and dual-frequency current superposition is realized through parallel output. The double-frequency LCCL resonant cavity has two parallel resonance points, a mode based on simplified topology is adopted to simplify parameter design, and meanwhile design errors are maintained at a low level. A power matching coefficient is introduced, the ratio of high-frequency output power to low-frequency output power is adjusted by adjusting the value of the power matching coefficient, and the problem of double-frequency power unbalance caused by frequency variation characteristics of load equivalent resistance and the like is solved. The superposed double-frequency current forms a low-frequency envelope embedded high-frequency oscillation composite waveform on the induction heating coil, cooperative control of tooth root deep quenching (low frequency) and tooth surface hard quenching (high frequency) is achieved, and the method has the advantages of being simple in parameter design, high in power decoupling performance, high in operation stability and the like.

A control device includes a modulation rate calculator configured to calculate a modulation rate based on a DC voltage on a DC side an, a limiter configured to update a DC voltage command lower bound limiter based on the lower bound limiter operation value; a maximum power point tracking controller configured to calculate a first DC voltage command value and determine a second DC voltage command value based on the calculated first DC voltage command value and the DC voltage command lower bound limiter set to the limiter, and an inverter controller configured to control an inverter of the power conversion system based on the second DC voltage command value.

A multiphase inverter for an electric drive system comprises multiple X-type multi-stage power converters positioned between a high-voltage DC power supply and an electric machine. Each of the multiple X-type multi-stage power converters is an integrated solid-state circuit (IC) comprising a positive DC power bus, a negative DC power bus, a neutral bus, and multiple semiconductor switches arranged in a stacked configuration. The multiple semiconductor switches are interconnected via the positive DC power bus, the negative DC power bus, and the neutral bus.

The invention discloses a soft switching HERIC non-isolated inverter and a modulation method thereof, and belongs to the technical field of inverters, the inverter comprises a bridge arm circuit, a clamping circuit, a resonance circuit, a voltage stabilizing circuit and a filter circuit, the resonant circuit comprises a first auxiliary switch tube, a second auxiliary switch tube, a third auxiliary switch tube, a fourth auxiliary switch tube, a first resonant inductor, a second resonant inductor, a first resonant capacitor and a second resonant capacitor; all high-frequency switches realize zero-current turn-on and turn-off at the same-direction stage of the voltage and the current of the power grid through the resonance circuit; all the high-frequency switches also realize zero-current switching on and switching off in the voltage and current reverse phase of the power grid; according to the modulation method, unipolar PWM modulation is adopted, the grid-connected current harmonic distortion rate is reduced, the grid-connected electric energy quality is improved, and the application value and prospect are huge.

Controlling a power converter circuit for a direct current (DC) power source is disclosed. The power converter may be operative to convert input power received from the DC power source to an output power and to perform maximum power point tracking of the power source. The power converter is adapted to provide the output power to a load that also performs maximum power point tracking.

The invention discloses a method and system for directly controlling the internal potential of a bridge arm of a new energy grid-connected inverter, belonging to the technical field of grid-connected inverter control. The control method comprises the following steps: obtaining measured values ​​by measuring the port voltage and current of the grid-connected inverter, and calculating instantaneous active and reactive values; obtaining the phase angle reference and amplitude reference of the internal potential of the bridge arm of the grid-connected inverter respectively, and then generating the internal potential reference of the bridge arm; at the same time, estimating the internal potential of the bridge arm of the grid-connected inverter based on the port voltage and current measured values ​​and the grid-connected inverter model by using an observer; finally, using the estimated internal potential as a feedback signal of the closed-loop feedback control of the internal potential, comparing it with the generated internal potential reference of the bridge arm, and sending it to the internal potential controller, thereby obtaining a modulation signal and sending it to the PWM module, so as to realize direct control of the internal potential of the bridge arm of the grid-connected inverter; compared with the existing control method of the grid-connected inverter, the method of the invention improves the dynamic performance of the grid-connected inverter and improves the power quality.

The present disclosure proposes an inverter circuit for an electric vehicle including an AC motor, including: a first relay connected after a first phase of the AC motor; after the second relay is connected to a second phase of the AC motor, one end, far away from the first phase, of the first relay is electrically connected with one end, far away from the second phase, of the second relay; the first output end and the second output end are used for outputting alternating current; a first capacitor disposed between the first output terminal and the second output terminal; and a third relay and a fourth relay, where the third relay is disposed between the first output and a first connection point, where the first connection point is located between the second relay and the second phase, and where the fourth relay is disposed between the second output and a second connection point, where the second connection point is located between the second relay and the second phase. The second connection point is located between the first relay and the first phase.

Described herein is a method of operating a power electronic converter device for an electrical power conversion system. The power electronic converter device includes a converter circuit including an input side, an output side, a first converter, and at least one second converter. The second converter includes at least one floating cell with a DC intermediate circuit and semiconductor devices. The method includes: switching the semiconductor devices of the floating cell at switching instants determined with optimized pulse patterns or carrier-based pulse width modulation; determining a fundamental voltage component for the floating cell; and generating the fundamental voltage component in the actual voltage of the floating cell by modifying the switching instants, such that a voltage VC AF of the DC intermediate circuit is lying in a given reference voltage range for balancing the DC intermediate circuit of the floating cell.