11392 results about "Inverter" patented technology

The invention relates to the field of power plant control, discloses a virtual power plant control method, system and equipment based on a neural network, and is used for solving the core problems of high data dependence, low topology safety and difficulty in multi-scale collaboration in traditional virtual power plant control. According to the virtual power plant control method based on the neural network, a correction instruction set, a joint estimation value and a topology constraint matrix are input into a neural network controller, and a cooperative control signal is output through singular perturbation decoupling of a fast-varying subsystem and a slow-varying subsystem. And the cooperative control signal is issued to the distributed power supply inverter, the energy storage converter and the intelligent switch, and meanwhile, an execution result is monitored in real time and fed back to the phase space reconstruction module, so that closed-loop control is formed. By constructing the Lyapunov candidate function and calculating the virtual damping coefficient, the transient stability, real-time persistent homologous analysis and topology self-healing instruction generation of the system are enhanced, and the self-healing capability and the fault-resistant capability of the system are improved.

The invention relates to a multi-source data electric energy quality energy-saving operation monitoring method and device based on AI Internet of Things, and the method comprises the steps: obtaining a transient electromagnetic signal of a permanent magnet operating mechanism circuit breaker, and extracting a time sequence characteristic parameter of the transient electromagnetic signal; judging whether a harmonic problem caused by an inverter exists or not and whether voltage suddenly rises or drops or not, and determining whether the time sequence characteristic parameters are associated with power quality disturbance or not; acquiring a voltage jump amplitude and a voltage swell rate to obtain a voltage fluctuation degree, and outputting a discharge strategy of the energy storage system through a pre-established discharge optimization model; respectively calculating to obtain a voltage distortion rate and a three-phase voltage unbalance degree, and selecting a charging strategy of the energy storage system through a pre-established charging optimization model; predicting a sudden rise rate and a sudden drop rate of the sample to obtain a prediction result, and forming an energy-saving optimization scheme of an energy storage charging and discharging strategy according to the prediction result; the charging and discharging power of the energy storage pool is automatically adjusted, an energy-saving optimization scheme is formed, and the stability of a power grid is effectively improved.

The invention discloses an inverter intelligent control method based on a self-adaptive algorithm, and relates to the technical field of inverter intelligent control, and the method comprises the steps: multi-source temperature collection and environment recognition, machine learning-based electric-thermal coupling prediction, self-adaptive inverter parameter optimization, and cooperative thermal management and fault diagnosis self-repairing. According to the high-temperature or low-temperature failure risk of the motor and the inverter under the extreme climate, temperature distribution and load information are obtained in real time, the temperature rise trend is predicted in advance, and the current, voltage and modulation strategy of the inverter are actively adjusted, so that safe derating or torque compensation is achieved; multi-sensor cross validation and observer fusion are carried out when sensors drift or devices are aged, stable operation and efficient energy utilization of the system are kept, and the drivability and the whole vehicle reliability in an extreme environment are remarkably improved; in the process, fault diagnosis and self-repairing can be further improved through online model updating, and the durability and economical efficiency of the electric drive system are improved.

The invention discloses a photovoltaic system abnormal data detection method and device, and relates to an abnormal detection technology based on a multi-head self-attention mechanism fusion variational auto-encoder and a bidirectional long short-term memory network (BiLSTM). Abnormal detection of electrical parameters (including DC voltage and current and AC voltage and current), environment parameters (relative humidity, wind direction and wind speed) and system parameters (including inverter error codes, inverter environment temperature difference, module environment temperature difference and the like) in a photovoltaic system is realized. The invention discloses a photovoltaic system abnormal data detection method. The method comprises the following steps: (1) photovoltaic system data acquisition and data processing; (2) encoding time sequence data of the photovoltaic system; (3) data sampling and data feature enhancement; (4) data decoding operation; and (5) detecting an abnormal value of the photovoltaic system.

The invention provides a frequency converter dynamic fault diagnosis method and system based on a multi-brand load test platform. According to the method, multiple real-time operation parameter sets are acquired, the amplitude attenuation threshold and the frequency fluctuation interval of a voltage waveform fragment are dynamically adjusted according to a load mode configuration file, the dynamic voltage reference parameter corresponding to the current load mode is generated, and then the actual waveform and an expected current phase curve are compared frame by frame; the method comprises the following steps: firstly, calculating to obtain a phase offset, then constructing a multi-dimensional operation characteristic spectrum, then carrying out time sequence cross validation on a sudden change time node of a power factor jump trajectory and an abnormal waveform position in a harmonic distortion incidence matrix, outputting an abnormal mode code, and finally, matching a load adaptation grade constraint condition to generate a diagnosis report; according to the technical scheme provided by the invention, the fault diagnosis precision and the cross-brand system adaptation capability in a complex load scene are remarkably improved, and the problem of misjudgment of a single brand threshold rule in a multi-device scene is effectively solved.

The present invention provides a method and system of self-adaptive setting of closed-loop parameters for suppressing PV coupling harmonics, comprising: acquiring node voltages and node currents of PV grid-connected inverters; constructing harmonic coupling admittance matrix according to the node voltages and node currents; calculating an amplitude of each element in the constructed harmonic coupling admittance matrix; screening contribution sources of coupling harmonics according to the calculated amplitude of the each element; evaluating quantitatively harmonic admittance of the PV grid-connected inverter according to screened contribution sources; and, carrying out optimization iteration for double-closed-loop PI control parameters of inverter with objective of minimizing the coupling harmonics of the PV grid-connected inverter according to results of the quantitative evaluation of the harmonic admittance, to complete self-adaptive setting of closed-loop parameters for suppressing PV coupling harmonics.

The invention relates to an inverter IGBT junction temperature prediction method and related equipment, and the method comprises the following steps: generating a loss characteristic spectrum through collecting IGBT electrical parameters and analyzing switching loss; calculating surface heat flux density, and constructing a heat flux distribution matrix. And performing thermal-electric coupling analysis by combining the two to obtain a junction temperature dynamic response sequence. Fourier transform is utilized to extract temperature fluctuation harmonic features, and a feature set is constructed; and extrapolating and predicting a junction temperature change trend based on the feature set, and outputting an IGBT junction temperature early warning signal through threshold judgment. The technical problem that the service life of a device is affected due to the fact that a large amount of loss is generated due to frequent switching actions in the working process of the inverter, the junction temperature of a chip rises and even temperature fluctuation occurs is solved.

The invention belongs to the technical field of power system stability control, and particularly discloses an inverter network following and constructing control mode adaptive adjustment method and system, and the method comprises the steps: obtaining a current power grid state parameter in real time; a multi-scale fusion depth evaluation model is constructed and trained; inputting the current power grid state parameters into the trained multi-scale fusion depth evaluation model, and outputting current power grid state evaluation indexes; according to the current power grid state evaluation index, adaptively selecting a control mode, wherein the control mode comprises a network following type inverter dominant mode, a network constructing type inverter dominant mode and a transition mode; and according to the selected control mode, verifying whether the power grid state satisfies a constraint condition, and if not, carrying out global optimization on the control parameters of the inverter. According to the invention, the dynamic stability and disturbance response capability of the power system can be improved through the adaptive adjustment of the network-following type and network-constructing type control modes of the inverter.

The invention relates to the technical field of resonance suppression, and discloses an active damping control LC resonance suppression method and device. The method comprises the following steps: performing parameter identification processing based on bus voltage to obtain an inductance value, a capacitance value and a resonance frequency of an LC circuit; extracting a resonant current component of the current signal based on the resonant frequency; calculating damping power according to the resonance current component, and converting the damping power into a voltage compensation instruction under an alpha-beta coordinate system; generating a PWM control signal according to the voltage compensation instruction and a voltage reference instruction; and performing on-off control on the inverter based on the PWM control signal, and injecting power opposite to the resonant current component into the LC circuit to generate a virtual damping effect. Virtual impedance characteristics are seamlessly integrated into inverter control, rapid response of the whole process from resonance detection to power injection is ensured, the resonance peak value is effectively suppressed, and the current quality is improved.

The disclosure provides a circuit modeling method for a dual-active-bridge-type micro-inverter. The method equates dual-active-bridge-type micro-inverter to a standard dual-active-bridge circuit by establishing an equivalent circuit model, thereby establishing a third-order large signal model and a third-order small signal model of the micro-inverter, so as to facilitate the solution of a circuit state variable and the analysis of the dynamic performance.

The invention provides a self-adaptive fuzzy control system for an inverter type arc welding power supply, and belongs to the field of welding process control and equipment automation, and the self-adaptive fuzzy control system specifically comprises the steps that a sensor module collects working numerical values corresponding to key parameters in the welding process in real time; the data processing unit converts the working values into a fuzzy set; the fuzzy controller executes fuzzy reasoning on the fuzzy set based on a preset fuzzy rule base so as to output a fuzzy control signal; the data processing unit performs defuzzification on the fuzzy control signal and converts the fuzzy control signal into an accurate control signal; the inverter power supply module receives the defuzzified accurate control signal to adjust the output power of the welding power supply; the feedback system monitors real-time parameters of welding seam quality in the welding process and transmits the real-time parameters to the self-adaptive module so as to realize closed-loop control; and the adaptive module dynamically adjusts the fuzzy rule base and the membership function according to the welding quality information provided by the feedback system. According to the processing scheme, the control precision and adaptability of the system are improved.

The invention discloses a three-phase permanent magnet synchronous motor full-speed-domain driving control system and a control method thereof. The system is composed of a torque limiting module, a full-speed-domain control neural network module, a current control module, a coordinate transformation module-I, a coordinate transformation module-II, a coordinate inverse transformation module, an SVPWM module, a SiC MOSFET driving module, a full-speed-domain position rotating speed observation module, a weak magnetic feedback module and a three-phase permanent magnet synchronous motor. The control method is used for driving the control system. According to the method, accurate tracing of the optimal dq-axis reference current working point is realized based on deep learning, and accurate control of three operation modes of MTPA, field weakening control and MTPV is realized; an improved mobile vision field estimation algorithm is adopted, and the rotor position and the rotor rotating speed are accurately estimated within the full-speed domain range; the SiC MOSFET is used as an inverter switching tube, and a brand new drive circuit is designed to adapt to the operation condition of the electric vehicle.

The invention discloses an output conversion system and method for a UPS (Uninterrupted Power Supply), and the system comprises a main power input end which is connected with a bridge rectifier through a first electromagnetic relay; the energy storage module comprises a super capacitor group and a parallel lithium battery group, and is coupled with the bus capacitor through a bidirectional DC / DC converter; the input end of the multi-path regulation and control module is connected with the bus voltage sensor, and the output end is connected with the switching execution unit through a second electromagnetic relay group; the dynamic switching unit comprises an I-GBT matrix and a reverse blocking diode array which are respectively connected with the inverter and the bypass circuit in parallel; and the real-time monitoring module is provided with a current harmonic analysis unit and a load break variable detection unit, and the output end of the real-time monitoring module is connected with the ADC port of the central processor. According to the invention, systematic improvement is realized in three dimensions of electric energy quality guarantee, equipment reliability and dynamic response capability through an original multi-path regulation and control architecture and a deep cooperative intelligent control strategy.

The invention relates to the technical field of elevator control and fault diagnosis, and discloses an elevator inverter fault pre-diagnosis and fault-tolerant control system and method based on digital twinning, and the system comprises a high-fidelity digital twinning body building module which is used for building a digital twinning body of an elevator inverter, the digital twin integrates an electric-thermal-stress coupling model, a device-level aging model, a parasitic parameter influence model and a driving circuit and protection logic model; wherein the electric-thermal-stress coupling model is used for simulating loss, junction temperature fluctuation and thermal stress circulation of a power device, and the device-level aging model is used for representing a time-varying degradation rule of device parameters. Through deep fusion of a digital twin technology, fault diagnosis and fault-tolerant control, a closed-loop system of'perception-pre-diagnosis-decision-control 'is constructed, the safety, reliability and economical efficiency of the elevator inverter are comprehensively improved, and the method has important significance in promoting transformation of the elevator industry to intelligent and unmanned maintenance.

The invention discloses a power grid cross-correlation harmonic suppression method, device and equipment and a storage medium, and the method comprises the steps: carrying out the wavelet packet decomposition of a subnet electric signal, and obtaining the harmonic component of a subnet at each frequency band; calculating the harmonic phase difference between the subnets according to the cross-correlation function between the harmonic components of the subnets and the topological impedance matrix, and calculating the total harmonic distortion rate according to the harmonic components of the subnets in the frequency bands; constructing a harmonic transfer equation according to the harmonic phase difference between the subnets and the equivalent output impedance of the inverter so as to calculate the harmonic responsibility proportion of the subnets; solving the double-layer game model based on the total harmonic distortion rate, the reference value of the total harmonic distortion rate and the harmonic responsibility proportion of the subnet, and obtaining the output of the governance equipment; and inputting the output of the treatment equipment into the fuzzy controller to obtain the impedance adjusting quantity of the subnet, and adjusting the virtual impedance according to the impedance adjusting quantity to update the harmonic backflow path. According to the invention, harmonic suppression among multiple subgrids during high-permeability distributed grid connection is realized, and the operation stability of the power grid is improved.

The invention discloses a fan control method, an inverter and an energy storage system. The control method is used for the inverter, operation data of the inverter in different environments and when the inverter operates in multiple working modes are obtained, the operation data comprise temperature data, voltage data, power data and current data, and the temperature data are temperature data of multiple temperature detection points; respectively solving correlation coefficients of the temperature of the inverter and the external environment temperature, voltage and power of the inverter according to the operation data and a fitting algorithm; solving a target coefficient of the correlation coefficient and the rotating speed duty ratio of the fan according to the operation data; constructing a rotating speed duty ratio control equation about the fan according to the target coefficient; the target rotating speed of the fan is solved according to the rotating speed duty ratio control equation and the current operation data of the highest rotating speed inverter of the fan; controlling the fan to work according to the target rotating speed. Thus, intelligent control over the fan can be achieved under different working conditions, and energy waste is avoided while normal operation of the inverter is guaranteed.

The invention discloses a VSG adaptive control method, which comprises the following steps: establishing an inverter model based on VSG control, introducing a virtual rotational inertia J and a damping coefficient D into the inverter model, introducing an SG2-order rotor motion equation to simulate the rotational inertia and realize primary frequency modulation characteristics, and deducing a control equation; establishing a VSG active-frequency loop small signal model, and introducing a transfer function of reference power-frequency and output power reference power to determine a variation range corresponding to the virtual inertia J and the damping coefficient D; and designing a fuzzy controller to dynamically adjust the virtual inertia J and the damping coefficient D in a variation range corresponding to the virtual inertia J and the damping coefficient D so as to realize real-time adjustment of the virtual inertia J and the damping coefficient D. According to the VSG adaptive control method, parameter adjustment is more sensitive in the face of small errors, and the selection range of J and D can be fully utilized and adjusted in real time.

The invention relates to an active and reactive collaborative optimization control method for a photovoltaic energy storage system based on a network-forming inverter, and the method achieves the effective control of active and reactive power through simulating the characteristics of a synchronous generator. And then collaborative optimization of active and reactive power control parameters is carried out. A system frequency response model is utilized to describe dynamic response of system frequency, and a dynamic equation of the system is converted into a discrete form in combination with the dynamic equation of the energy storage unit. Meanwhile, the optimization model is solved by considering system capacity limitation, so that transient frequency characteristics are improved, and frequency deviation after system disturbance is reduced. In addition, the minimum active power loss is taken as an optimization target, the voltage deviation is taken as a penalty term to be substituted into a target function, and a reactive power optimization target function is established. A PSO algorithm is adopted to solve a reactive power optimization function, and reactive power output of photovoltaic and energy storage is adjusted by adjusting VSG control parameters, so that the economical efficiency of a power grid is improved on the premise of ensuring qualified voltage.

The invention relates to the technical field of energy storage systems, and discloses a three-phase parallel operation system and a power distribution method and device thereof. The method comprises the following steps: acquiring initial distribution power of each phase of each energy storage inverter; determining a locked phase, a non-locked phase, a locked energy storage inverter and a non-locked energy storage inverter according to the initial distribution power of each phase of each energy storage inverter; determining missing power of the locked phase of the locked energy storage inverter according to the locked energy storage inverter and the locked phase; according to the initial distribution power of the non-locked phase of the locked energy storage inverter, the charging margin is obtained; according to the initial distribution power of the non-locking phase of the non-locking energy storage inverter, obtaining a discharge margin; and obtaining the target distribution power of each phase of each energy storage inverter according to the missing power, the charging margin and the discharging margin. Through overall calculation of the global margin, the problems that interphase power of a traditional parallel operation system is rigid and the overall performance is restricted by a single-point bottleneck are solved, and the load adaptability and the operation reliability of the parallel operation system are remarkably improved.

The invention relates to the technical field of power distribution network analysis, in particular to a distributed energy storage cooperative control system and device for an intelligent power distribution network, in the distributed energy storage cooperative control system and device for the intelligent power distribution network, inverter phase angles and bus voltage fluctuation characteristics are collected in real time through a dynamic virtual impedance parameter library, and a virtual impedance parameter library reflecting a disturbance propagation path is constructed; a lower-layer region dynamic division unit of the double-layer decision control module dynamically divides cooperative control sub-regions based on a virtual impedance deviation value and a preset clustering interval, and improves local disturbance suppression precision in combination with power grid topology constraints, and an upper-layer weight distribution unit generates a dynamic power distribution weight coefficient according to an inverse proportion relation of an equivalent impedance ratio; the overload risk caused by traditional fixed weight distribution and impedance characteristic mismatch is solved; when the energy storage unit is off-network, the power disturbance buffer factor calculation module adjusts the upper limit of output of the remaining units according to the original weight proportion and the equivalent impedance ratio in an equal-ratio scaling mode, and output adjustment and the impedance attenuation direction are maintained to be synchronous.

The invention discloses a micro-grid electric energy quality global optimization method, which comprises the steps of collecting real-time data, dividing the real-time data into a plurality of segments according to frequency, and calculating harmonic compensation capacity of each frequency band according to the real-time data; according to the harmonic compensation capacity obtained through calculation, priority distribution is carried out on the compensation sequence of the polluted nodes in the micro-grid; the virtual impedance and the injection damping resistance of the inverter are adjusted, and the harmonic current and the resonance phenomenon in the micro-grid are suppressed in different frequency bands; and according to the adjusted virtual impedance and damping resistance, updating a node admittance matrix, monitoring the compensation capacity of the inverter in real time, comparing real-time monitoring data with a threshold value, if the real-time monitoring data exceed the threshold value, correcting the inverter, otherwise, not changing. Through frequency-band-divided control, pertinence and effect of harmonic suppression are improved, frequency-band-divided suppression of micro-grid harmonic and high-frequency resonance is realized, residual capacity of an inverter and harmonic compensation requirements are dynamically matched, and safe and stable operation of a system is ensured.

The present invention discloses a prediction method for a crosstalk spike in a half bridge of current-source inverter with silicon carbide devices, where, the prediction method includes calculation of the crosstalk voltage spike in the circuit of current-source type double-pulse test and analysis of the effect of each parameter on the magnitude of the crosstalk spike. The prediction method of the present invention analyzes the horizontal conduction crosstalk mechanism between the gate-source junction of the MOSFET caused by the high-frequency switching action of the silicon carbide (SiC) MOSFET and the SiC Schottky diode connected in series, and derives the prediction model for the crosstalk voltage spike in the half-bridge of current-source inverter. Based on the equivalent circuit of the current-source-type double-pulse test and the crosstalk-induced mechanism, the extreme value of crosstalk voltage spike is accurately predicted, which is helpful to analyze the effects of the drive circuit and the parameters of the power circuit on the crosstalk voltage spike through the prediction model.

The invention relates to the technical field of parallel connection of energy storage inverters, in particular to a synchronous control method of an energy storage inverter system supporting multi-machine parallel connection, which comprises the following steps of: according to a preset rule, assigning one inverter as a master node and the other inverters as slave nodes; when it is detected that the running state of the main node exceeds a preset abnormal threshold value, a main control switching process is triggered; dynamically electing a new host strategy based on a preset priority, and dynamically electing an inverter as a new host node; the other inverters synchronously switch the tracking target and update the synchronization reference; in the switching process, the new main node smoothly establishes a voltage reference by adopting a phase pre-synchronization and slope transition strategy. According to the invention, by introducing a dynamic master node switching mechanism, when the master node is abnormal, the master control responsibility is automatically, quickly and smoothly transferred to the healthy slave node, the AC side voltage frequency synchronization and the DC side bus voltage stability are maintained, and the continuous and stable operation of the multi-machine parallel system under the condition of the master node fault is ensured.

The invention discloses a sequence impedance modeling method for a network-forming droop control inverter, which belongs to the technical field of power electronic inverter system modeling and comprises the following steps of: S1, obtaining dq component expressions of output voltage and output current of the inverter; s2, obtaining a frequency domain expression of output voltage and output current of the dq coordinate system droop control inverter after small signal disturbance is considered; s3, obtaining a frequency domain expression of three-phase modulation wave output internal potential of the droop control inverter; and S4, obtaining small-signal positive and negative sequence impedance models of the net-forming droop control inverter. According to the method, the complete and comprehensive sequence impedance model of the grid-forming type droop control inverter with clear physical significance can be accurately established, a basis for impedance matching optimization is provided to reduce harmonic oscillation, small-disturbance stability analysis can be carried out, application of the grid-forming type inverter in a micro-grid can be promoted, and the method is suitable for popularization and application of the grid-forming type droop control inverter in the micro-grid. And an environment-friendly and economic-friendly grid-connected system is established.

The present teaching relates to method and system for charging a rechargeable battery deployed in an electric apparatus. The system resides in the electric apparatus. The system comprises a motor, an inverter, an output rectifier, a configurator, and a controller. The motor comprises a stator having a plurality of stator teeth and a plurality of stator windings wounded on the plurality of stator teeth. The inverter comprises a plurality of power switch devices. The configurator comprises a plurality of contactors coupled with the plurality of stator windings and the plurality of power switch devices. The controller controls the plurality of power switch devices and the plurality of contactors, so as to configure the system to operate in one of a traction mode and a charging mode.

The invention relates to the technical field of frequency converter anomaly detection, in particular to a hydraulic engineering frequency converter state detection method and system. The invention aims to improve the accuracy of abnormal data point detection in the frequency converter performance parameter time sequence data, and particularly focuses on the influence of environmental factors on performance parameters. Performance parameter time sequence data and environment parameter time sequence data are synchronously obtained, discrete wavelet transform is used for decomposing performance parameters in a multi-layer mode, and approximation coefficients are mainly analyzed to insight the operation state of the frequency converter. And after the suspected abnormal data segments are preliminarily screened, environment abnormal indexes are calculated in combination with environment parameters, and fluctuation degree values of the suspected abnormal data segments are analyzed. And based on the environmental anomaly index and the fluctuation degree value, adaptively adjusting the initial threshold value of each approximation coefficient to obtain an adaptive threshold value, and finally detecting abnormal data based on the adaptive threshold value. According to the method, abnormal data points caused by environmental factors can be effectively eliminated, and abnormal data points caused by abnormity of the frequency converter can be accurately identified.

The invention discloses an inverter parallel single bus active carrier phase synchronization method. A host sends a carrier synchronization signal to a slave through a synchronization signal line at a carrier counting zero point; the slave reads numerical values in the basic calibration register, the time deviation register and the period register while receiving the carrier synchronization signal, and calculates a deviation value delta psi of carrier phases of the current slave and the host; and compensating the period deviation in the period register through the deviation value delta psi, so that the carrier counting zero point of the slave is aligned with the carrier counting zero point of the host. An existing hardware system does not need to be expanded, extra hardware cost is not increased, and the hardware size is not expanded. And the carrier wave difference of different master and slave controllers can be dynamically compensated according to an established parallel operation system. The carrier synchronization of the host and the slave is realized in a carrier phase deviation period, the synchronization speed is high, the precision is high, the synchronization can be locked after synchronization, and the condition of carrier synchronization failure in the operation process is avoided. And the stability is excellent.

The invention relates to the technical field of industrial control, in particular to a battery SOC balance control method, an inverter parallel operation system, equipment and a medium. The battery SOC equalization control method comprises the following steps: according to a preset equalization period, a current inverter obtains a battery actual SOC of a high-voltage battery connected with the current inverter, and provides the battery actual SOC for a preset host so as to obtain an average SOC provided by the preset host according to the battery actual SOC; obtaining an SOC difference value between the actual SOC and the average SOC of the battery, and obtaining a current correction value based on the SOC difference value; and obtaining the charging and discharging states of the inverter parallel operation system and the battery current threshold value of the high-voltage battery, and correcting the battery current threshold value by adopting the current correction value based on the charging and discharging states to obtain a final current threshold value. According to the invention, the balance of the SOC of the inverter parallel operation system is improved, the overhigh load of part of inverters is avoided, and the fault risk is reduced, so that the stability and reliability of the inverter parallel operation system are enhanced.

A low voltage ride through control method for a grid-forming inverter based on dynamic internal potential adjustment comprises the following steps: detecting a voltage per unit value of a grid-connected point in real time, and comparing the voltage per unit value with a threshold value to judge a voltage drop event and trigger low voltage ride through control; dynamically calculating active and reactive power reference values through a reactive compensation equation and an active current limiting equation according to the voltage amplitude and the power reference value before falling during the ride-through period; inputting the active reference value into a virtual rotor motion equation to generate a reference phase, and outputting a phase reference signal in combination with a dual-mode phase compensation controller; superposing the reactive reference value with the reference voltage through a reactive voltage regulating ring to generate a voltage amplitude reference signal; synthesizing an internal potential according to the phase and the amplitude reference signal, and obtaining an inductive current reference value through virtual impedance control and current amplitude limiting; and finally, a driving signal is generated through the current inner loop controller and the modulation module. According to the invention, overcurrent can be effectively inhibited, rapid reactive power support is provided, and synchronous stability and smooth transition in a fault period and a recovery process are ensured.

The present application provides a reactive power feedback control-based control method for a commutation failure in a hybrid cascaded high-voltage direct-current power transmission system, a storage medium and an electronic apparatus, and particularly relates to a reactive power feedback control-based control method for a commutation failure in a hybrid cascade high-voltage direct-current power transmission system. The method mainly comprises the following steps: acquiring power data of a hybrid cascaded high-voltage direct-current power transmission system; calculating the reactive power supply of an inverter-side MMC-end alternating-current system, the reactive power supply of an inverter-side alternating-current filter, and the reactive power supply of an inverter-side LCC-end alternating-current system; solving a reactive power control instruction of an inverter-side MMC converter; and, on the basis of a critical voltage, determining whether to implement the reactive power feedback control-based control method for a commutation failure in the hybrid cascaded power transmission system. The method can effectively reduce the probability of commutation failures in hybrid cascaded power transmission systems, thus guaranteeing safe and stable operation of large-scale power grids.