363 results about "Inner loop" patented technology

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 invention discloses a control method of an interleaved parallel bidirectional DCDC converter. A circuit of the converter comprises three pairs of MOSFET switch tubes, three inductors and an output capacitor. The phase difference of PWM waves of the three pairs of MOSFET switch tubes is 120 degrees, and the phase difference is used for effectively reducing current ripples through staggered complementation of currents of all phases. Double closed-loop control is adopted, the DSP chip is responsible for current inner loop control, and the FPGA chip is responsible for voltage outer loop and power outer loop control. The current sharing precision is high, through flexible configuration of multiple proportionality coefficients and zero points, input fluctuation and load abrupt change interference can be accurately restrained, oscillation is avoided, stable output is ensured, and when load abrupt change or mode switching is carried out, output can be rapidly adjusted, transition time can be shortened, and overshoot can be reduced. And high dynamic response and strong robustness of the system are realized, so that complex and changeable application requirements are met.

The invention relates to a DSTATCOM harmonic current detection and tracking control method, which comprises the steps of collecting instantaneous current and instantaneous voltage of a load side of a power distribution network, processing a power distribution network instruction current signal detected in real time through an improved dq0 compensation amount detection algorithm, obtaining a to-be-compensated negative-sequence frequency doubling component and a to-be-compensated specific subharmonic component, and carrying out harmonic current tracking on the to-be-compensated negative-sequence frequency doubling component and the to-be-compensated specific subharmonic component. The obtained negative sequence frequency doubling component and the specific sub-harmonic component to be compensated are sent into a current inner loop, three-phase reference voltage is obtained through a PIR controller, generation of PWM pulses is controlled, then on-off of a DSTATCOM bridge arm switching tube is controlled, and a closed-loop control system is formed. A path for extracting an orthogonal component in instruction current is reconstructed, the positive sequence fundamental current detection error under the three-phase imbalance working condition is remarkably reduced, a compensation current control strategy based on a PIR controller is adopted in a current inner loop, and zero-static-error tracking of a frequency doubling component and a low-frequency harmonic component in compensation current is achieved.

The invention belongs to the technical field of grid-connected inverter harmonic analysis, and particularly discloses a grid-connected inverter harmonic closed-loop transmission analysis method and system considering broadband coupling. The method comprises the following steps: respectively establishing a harmonic component transfer function of each module; based on the harmonic component transfer function of the sampling module, calculating to obtain harmonic active power and harmonic reactive power input to the power outer loop control module; based on a harmonic component transfer function of the power outer loop control module, calculating to obtain a harmonic current component in a reference current signal output by a power outer loop; based on a harmonic component transfer function of a current inner loop control module, obtaining a three-phase modulation voltage harmonic component and an inverter port voltage harmonic component through coordinate inverse transformation; on the basis of the inverter port voltage harmonic component, a main circuit harmonic transfer equation is combined, and a grid-connected point harmonic current component is obtained through calculation; the method overcomes the defects that a traditional analysis method cannot consider the control of a whole loop by a closed loop, and the broadband coupling is insufficiently considered.

The invention relates to a ripple suppression PI loop control method, a storage medium and a device, and the method comprises the steps: extracting a frequency doubling component in an inversion power flow based on the filtering and Park transformation of a secondary second-order generalized integrator, determining the reverse compensation amount at each moment based on the frequency doubling component and a battery connected with a DC circuit, and carrying out the control of the ripple suppression PI loop. And finally, based on the sum of the reverse compensation amount at each moment and an original reference current value output by a voltage outer ring on each bridge arm of the DC circuit, determining a current reference instantaneous value after reverse compensation of a current inner ring input to each bridge arm at each moment. According to the method, a pure frequency doubling component with very high dynamic performance and related to ripple information is obtained, then according to the extracted frequency doubling component and battery parameters, the reverse compensation amount used for suppressing ripple in loop control is obtained, and then the reverse compensation amount is accumulated to a voltage outer loop, so that the ripple information is suppressed. Therefore, ripple suppression with good dynamic performance and good suppression effect in loop control is realized.

The invention relates to the technical field of aircraft control, in particular to a four-rotor unmanned aerial vehicle robust trajectory control method based on a sliding mode control-improved extended state observer. The method comprises the following steps: firstly, establishing a nonlinear dynamic model of the quad-rotor unmanned aerial vehicle, and decomposing the system into a hierarchical control structure of a position outer ring and an attitude inner ring; secondly, a third-order extended state observer (ESO) is designed to estimate composite disturbance of each channel in real time, an improved sliding mode control law with observation error compensation is provided, and the vibration bearing phenomenon is effectively restrained; and finally, proving the asymptotic stability of the closed-loop system through the Lyapunov stability theory. The method is used for solving the problems of low trajectory tracking precision and control signal buffeting caused by underactuation, strong coupling nonlinear characteristics and external disturbance of the four-rotor unmanned aerial vehicle. High-precision trajectory tracking under complex disturbance can be realized, and control signal buffeting can be suppressed at the same time.

The invention provides a network construction type converter control method suitable for multiple power grid intensities, and belongs to the field of new energy grid-connected stability. The method comprises the steps that the actual output power of an inverter is calculated according to inverter side capacitor voltage and grid-connected current; the actual output power of the inverter and the power reference value control an output internal potential amplitude reference value and an internal potential phase angle through the virtual synchronous generator; subtracting the voltage drop of the grid-connected current on the virtual impedance from the internal potential amplitude reference value to obtain a virtual internal potential; inputting the virtual internal potential as a reference voltage into a voltage and current double-loop controller, inputting a grid-connected current into a proportional differential controller, subtracting the output of the proportional differential controller from the output of the voltage and current double-loop controller, inputting an obtained result into an inverter through an SPWM modulator, and controlling the inverter; the invention also provides a control system of the network-forming converter. Grid-connected current proportional differential feedback is introduced, the inner loop control bandwidth is kept constant in the dynamic change process of the power grid strength, and power-voltage loop harmful coupling is eliminated.

A seamless switching method and device for network-oriented MMC-HVDC converter station construction and network following control, relates to the field of power system control technology, without changing the inner loop current control, by constructing a unified outer loop reference current and initializing the setting of phase angle and voltage amplitude, the continuity of output voltage power angle and amplitude in the control mode switching process is ensured. The technology can quickly respond to changes in grid conditions, avoiding system disturbance and instability caused by mode switching. Simulation results show that this technology effectively reduces the impact of control switching on the system, significantly improves the stability and reliability of the system, and is suitable for flexible HVDC transmission systems under various grid conditions, especially in weak grid access and frequency support scenarios.

The invention discloses a six-phase motor driver harmonic current suppression method based on multi-subspace control, and belongs to the technical field of motor control. In order to solve the problem that low-order harmonic current of a six-phase motor in a z1-z2 subspace is difficult to effectively suppress, the invention provides a scheme that a mathematical model of the six-phase permanent magnet synchronous motor is established, multi-subspace decomposition is carried out, and stator current is divided into a d-q subspace and the z1-z2 subspace; a double-closed-loop control architecture with a speed loop as an outer loop and a current loop as an inner loop is constructed, a d-q subspace adopts a PID regulator to realize fundamental current control, and z1-z2 subspaces realize suppression of fifth and seventh harmonic currents through a parallel structure of PI and a quasi-proportional resonance controller; and a PWM signal is synthesized through inverse transformation and dual three-phase space vector pulse width modulation, and an inverter is driven to realize stable output of fundamental wave energy and harmonic suppression. The method effectively reduces the harmonic distortion rate, improves the operation efficiency and stability, and is suitable for occasions of new energy vehicles, ship propulsion, rail transit and the like.

The application discloses a multi-phase motor communication-free redundancy control system and a control method, which comprises a rotating speed controller, a reference current selection module, a plurality of inner loop current controllers and a plurality of modulation and driving modules. The rotating speed controller receives a given reference rotating speed of a motor and an actual rotating speed of each set of windings, and outputs a q-axis reference current in a dq rotating coordinate system. The reference current selection module receives the q-axis reference current, specifies a master winding and a slave winding in the plurality of windings, and outputs a d-axis and q-axis reference current of each redundancy. The inner loop current controller is connected with the reference current selection module, receives the d-axis and q-axis reference current of the corresponding winding and a feedback current thereof, and outputs corresponding d-axis and q-axis reference voltage. The plurality of modulation and driving modules drive and control each winding. The application realizes communication-free control through master-slave following of the windings, can avoid the problem of collaborative failure caused by communication failure, and thus improves the steady-state performance of the motor.

The invention discloses a test control method and system for a direct-current power supply, and relates to the field of simulation testing, and the method comprises the steps: constructing a three-dimensional adaptive model to complete the matching calibration of system software and hardware, and achieving the load calibration through the comparison of dynamic load simulation and actual measurement data; in the testing process, a three-stage starting mechanism is adopted to power on step by step, fault protection is configured, and parameter scanning and real-time recording are executed according to a preset mode and a testing point; a double-closed-loop feedback mechanism is introduced, an inner loop adjusts output parameters, and an outer loop predicts power grid disturbance and performs advanced compensation; a safety threshold value is dynamically generated in combination with real-time environment data, linkage protection of approaching early warning and overrun protection is achieved, and a reliable effective data set is formed through fusion processing and double verification of multi-source test data. The system has the advantages that the precision and intelligence of the whole test process are realized through dynamic load simulation, a multi-level safety protection system is constructed through a three-level starting mechanism, and the precision, safety and data value of the test are comprehensively improved.

The invention discloses a gate valve opening degree control method and device, and relates to the technical field of industrial automation control, and the method comprises the following steps: obtaining valve structure data and actuator types, reading an initial value of a valve position sensor, building a valve position zero point, and loading an initial valve position-flow mapping model; an error is calculated according to the target process variable and the current measured value, and a valve position target value is generated through an outer ring controller; querying the valve position-flow mapping model according to the valve position target value, and performing deviation correction in combination with real-time flow measurement to obtain a corrected valve position target value; the friction state is predicted according to the valve position change rate and the actuator current signal, the friction compensation amount is generated, the corrected valve position target value is corrected, and a final valve position instruction is obtained; and the final valve position instruction is compared with the actual valve position, the driving amount is calculated through an inner ring controller, an actuator is driven to act, and the actual valve position is made to approach the final valve position instruction.

The invention discloses a network construction type SVG (static var generator) control method based on data-driven optimal self-synchronization. Obtaining the capacitor voltage of the direct current side of the SVG and the actual voltage and the actual current of the grid-connected point; constructing a DeePC controller input according to the actual voltage of the grid-connected point, the SVG direct current side capacitor voltage and a preset reference value, and obtaining a frequency deviation through the processing of the DeePC controller; adding the frequency deviation and a power grid rated frequency to obtain a controller frequency, and integrating to obtain a modulation wave phase signal; according to the SVG output voltage reference value, the actual voltage is sequentially processed by a voltage outer loop, current amplitude limiting and current inner loop to obtain a modulation wave voltage amplitude signal; and processing the modulated wave phase signal to obtain a modulated wave signal. According to the method, the control sequence is optimized online by directly utilizing the voltage data collected in real time, the mismatching risk of a traditional model is avoided, and a reactive power support solution with better dynamic response and autonomous toughness is provided for a new energy power grid.

The invention discloses a generator stator grounding fault active arc extinction method based on double-loop quasi-PR control, and the method comprises the following steps: S1, monitoring the fundamental wave zero-sequence voltage and third harmonic voltage of a neutral point and a generator end of a generator, and carrying out the fault phase selection and positioning when a single-phase stator grounding fault occurs; s2, according to a fault positioning result, calculating a fault winding potential Ef, and setting a negative value-Ef of the fault winding potential Ef as a neutral point target compensation voltage; s3, a cascaded H-bridge converter is adopted as a topological structure of the active regulation and control device, and a double-closed-loop control framework composed of a voltage outer loop and a current inner loop is established; s4, setting quasi-PR control units for the fundamental wave component and the third harmonic component in the voltage outer ring and the current inner ring respectively; and S5, controlling the cascaded H-bridge converter to output a compensation voltage consistent with the target compensation voltage-Ef, and injecting the compensation voltage into the neutral point of the generator. The voltage regulation and control precision and the arc suppression speed in the active arc suppression process of the generator can be improved, and the operation safety and reliability of the generator are improved.

The invention provides a light load control method, an LLC resonant converter using the same and a storage medium, the method is based on a double closed-loop control structure of a voltage outer loop and a current inner loop, different load conditions are adapted by automatically switching a PFM mode, a PWM mode and a BURST mode, and the method comprises the following steps: setting control parameters; sampling an output voltage Vout and an output current Iout of the LLC resonant circuit; inputting a voltage error obtained by comparing a preset reference voltage Vref with the output voltage Vout into a PI controller of a voltage outer loop, and calculating to obtain a reference current Iref; a current error obtained by comparing the reference current Iref output by the voltage outer loop with the output current Iout is input into a PI controller of the current inner loop; and judging the working mode of the current control period according to the duty ratio Duty of the previous control period and the frequency demand f output by the current inner loop. According to the invention, through combination of double closed-loop control and three-mode intelligent switching, comprehensive optimization of efficiency, dynamic response and output voltage quality in a full-load range is realized.

The invention discloses a multi-agent-driven security alarm log simulation generation method, and relates to the technical field of network security, and the method comprises the following steps: S1, obtaining a sample log; s2, on the basis of the sample log, obtaining and defining an overall feature as Ft, a session feature as Fs, a field feature as Fc, an overall rule as Rt, a session rule as Rs and a field rule as Rc; s3, Ft, Fs, Fc, Rt, Rs and Rc are input into the large language model, logs are generated, and the generated logs are classified into overall logs, session logs and field logs; s4-S6, performing outer-layer circulation, middle-layer circulation and inner-layer circulation on the basis of the generated overall log, session log and field log, so as to obtain a final simulation security alarm log set; and S7, performing quality evaluation on the generated simulation security alarm log. According to the method, the security simulation logs meeting the requirements are generated through various agents, and the method is very valuable in scenes such as security testing, security simulation and application security testing.

The invention relates to an aiming point dynamic stabilization and automatic calibration method fusing inertial measurement unit data, and belongs to the technical field of aiming equipment dynamic control. The method comprises the following steps: acquiring attitude data of an inertial measurement unit, and constructing a multi-source data matrix in combination with real-time position data of an aiming point and environmental interference data; after time sequence synchronization and drift suppression are carried out on multi-source data, associated feature vectors are extracted through multi-modal feature fusion; inputting a self-adaptive extended state observer to estimate total disturbance and generate an anti-interference compensation amount, constructing a kinetic model in combination with a nonlinear model prediction controller, solving a multi-objective optimization problem, and generating an attitude compensation control sequence to realize dynamic stability of an aiming point; and finally, aiming deviation is calculated in real time to trigger double-closed-loop calibration, an inner ring corrects the drift error of the inertial measurement unit, and an outer ring optimizes parameters of the observer and the controller. According to the invention, environmental interference and inertial drift are effectively suppressed, the dynamic aiming stability is improved, and the long-term aiming reliability is guaranteed through closed-loop calibration.

The invention relates to the technical field of modular multilevel converter control, in particular to an active-disturbance-rejection direct-current side fluctuation suppression method based on an MMC alternating-current side fault working condition. The method mainly aims at solving the problems that an existing suppression scheme based on a PI controller is insufficient in performance and difficult in parameter adjustment, and a control scheme based on an active disturbance rejection controller is complicated in parameter debugging and difficult in obtaining optimal parameters although the performance is better. The method comprises the following steps: step 1, suppressing a negative sequence current generated by an MMC system when an alternating current side has a fault; step 2, constructing a second-order LADRC model; and step 3, current inner loop control is carried out by using a second-order LADRC controller set by a particle swarm optimization algorithm. According to the method, a traditional PI controller is replaced by the second-order LADRC controller, parameters are set in combination with the particle swarm optimization algorithm, the ride-through capacity of the MMC system under the alternating current side fault is remarkably improved, and better dynamic response and interference immunity are achieved.

The invention relates to a dual-mode seamless switching three-phase grid-connected inverter control system and method. The system comprises a GFL outer loop control module, a GFM outer loop control module, a current inner loop control module, a power grid impedance tracking module, a calculation processing module and a switching buffer control module. The power grid impedance tracking module is used for detecting and calculating power grid impedance Lg in real time; the calculation processing module analyzes the power grid impedance Lg and then generates a switching control instruction group, the switching buffer control module receives the switching control instruction group, and a plurality of change-over switches in the switching buffer control module change states according to instructions so as to select to start a GFL or GFM control path; according to the cooperative working mechanism, the system can automatically and smoothly switch between the following network type control strategy and the construction network type control strategy in real time according to the impedance state of the power grid, so that the adaptability and the operation stability of the three-phase grid-connected inverter under the wide-range power grid impedance change are remarkably improved.

The invention discloses a stacking machine anti-swing method and system based on double closed-loop control, and relates to the technical field of automatic warehousing, and the method comprises the following steps: obtaining a disturbance signal in the operation process of a stacking machine, and evaluating the speed deviation change of a motor based on the disturbance signal to obtain a disturbance response feature; recognizing an inner ring speed deviation section based on the disturbance response characteristics, and correcting the inner ring speed based on the inner ring speed deviation section to obtain a speed control signal; based on the speed control signal, carrying out segmented constraint on the speed output by a preset sliding mode variable structure to obtain a speed constraint set; according to the method, the current stacking machine moving trajectory is replanned based on the speed constraint set, the planned stacking machine moving trajectory is obtained, feedback displacement errors of the inner ring and the outer ring are analyzed, and the stacking machine is prevented from swinging according to the analysis result. And the problem of swinging overshoot caused by motor speed fluctuation and external disturbance is solved.

The invention also discloses an SIDO Boost converter terminal complementary superspiral sliding mode improved active-disturbance-rejection control method. The method specifically comprises the following steps: step 1, establishing a state space averaging model by using a state space averaging method; 2, fitting the state space average model into a standard second-order system normal form; 3, designing a fractional order cascade expansion state observer according to a standard second-order system normal form; step 4, applying the observation value obtained in the step 3 to a terminal complementary sliding mode controller; 5, introducing the super-spiral sliding mode reaching law into the terminal complementary sliding mode; step 6, according to the equivalent control law and the switching control law, obtaining a total control law of the system after summation; and step 7, applying the observer and the controller to a main voltage single closed loop and a branch voltage outer loop and a current inner loop. The problems that a traditional active-disturbance-rejection control method is insufficient in external total disturbance estimation precision of the single-inductor dual-output converter and cross influence exists between two output branches are solved.

The invention provides a control method and device for improving strong network adaptability of a network construction converter and a storage medium, and relates to the technical field of power grids. The method comprises the following steps: acquiring active power and reactive power of a grid-connected point, and inputting the active power and the reactive power into a VSG ring to obtain a virtual synchronous machine internal potential amplitude and a virtual synchronous machine internal potential phase; adaptively acquiring a reference node phase, and subtracting the reference node phase from the internal potential phase of the virtual synchronous machine to obtain a power angle; generating an active reference current and a reactive reference current based on the power angle and the potential amplitude in the virtual synchronous machine; and inputting the active reference current and the reactive reference current into a current inner ring to obtain a switching control signal of the target grid-connected converter. The power angle observer is added in the power outer loop, the current reference value is generated according to the power angle, dependence on a voltage loop is not needed, the reference node phase is obtained in a self-adaptive mode, and better stability performance is achieved under a strong power grid and a weak power grid.

The application discloses a harmonic compensation and stability improvement method, system, medium and equipment, filters components of a grid voltage in a two-phase static coordinate system to obtain corresponding fundamental components; subtracts the fundamental components of the grid voltage from the components of the grid voltage in the two-phase static coordinate system to obtain total harmonic components of the grid voltage; filters the total harmonic components of the grid voltage by using multiple band-pass filters to obtain multiple harmonic components corresponding to frequencies; subtracts reference current instructions of an active power filter from the multiple harmonic components, and inputs the result as a new current reference instruction into a current controller; and based on a virtual harmonic admittance method, outputs harmonic compensation currents through current inner loop control in the two-phase static coordinate system to realize harmonic compensation on a nonlinear load with frequency coupling characteristics and suppression of harmonic compensation oscillation. The application can adapt to various complex grid environments and has relatively practical engineering application value.

The application belongs to the cross field of electric power system and power electronics technology, and particularly relates to a regional power grid power quality treatment method for multi-type subject access. By introducing advanced phase compensation, the phase lag of the detection link is calculated and fully compensated in real time, so that the extracted harmonic component is instantaneously synchronized with the actual harmonic of the power grid. In combination with an adaptive hybrid modulation technology, the dominant harmonic frequency band can be focused on compensation. A fully decoupled control based on feedforward is adopted, which eliminates the cross coupling between the d and q axis currents, so that the inner loop controller can realize fast tracking with almost no overshoot. Meanwhile, the adaptive adjustment mechanism of the PLL bandwidth ensures that the synchronization signal is fast and robust when the power grid changes.

The invention relates to the technical field of power system application, and discloses a unified control method, system, equipment and medium for a flexible interconnection device based on a multi-voltage-level direct-current power distribution network, and the method comprises the steps that the flexible interconnection device is composed of two alternating-current / direct-current converters which are connected back to back, one side adopts direct-current voltage and reactive power control, and the other side adopts direct-current voltage and reactive power control; and the other side adopts active power and reactive power control. Decoupling control is carried out on d-axis current and q-axis current under a synchronous rotating coordinate system, a d-axis current reference value of a PQ side is superposed to a voltage outer ring output of a UdcQ side, and a unified current inner ring reference instruction is generated. According to the method, a feed-forward compensation item is introduced into a current inner loop to offset inter-axis coupling, continuous smooth adjustment of bidirectional power flow can be achieved without switching a control mode, voltage fluctuation of a direct-current bus is effectively restrained, and the dynamic response and global stability of a system are improved.

The invention provides an energy storage system black start method and system based on hierarchical control, and the method comprises the steps: carrying out the secondary frequency modulation and voltage regulation of a collected common voltage at a station control layer, so as to obtain a regulation variable, and transmitting a starting instruction, an off-grid mode enabling instruction and the regulation variable to a square matrix layer; a master matrix and a slave matrix are determined, the master matrix is controlled to perform black start, the master matrix is converted into an off-grid state after black start succeeds, and the black start of the master matrix comprises power loop control and voltage outer loop control performed by the master matrix and current inner loop control of an energy storage converter layer; controlling in-station alternating current bus voltage from grid connection of the square matrix to construction of the main square matrix, and converting into an off-grid state after grid connection is completed; and after receiving the off-network state information of the master square matrix and the off-network state information of the slave square matrix, the station control layer is switched into an off-network state, and the black start of the energy storage system is completed. According to the method, hierarchical control is carried out on the system, the advantages of serial recovery and parallel recovery are combined, and the stability of the system is ensured while the black start speed of the system is increased.

This invention discloses an adaptive impedance control method and system for a robotic arm based on inner-loop performance feedback and an energy tank. It constructs a collaborative impedance control framework with inner and outer loops: the outer loop employs a reinforcement learning-based impedance controller, while the inner loop uses a sliding mode controller. The dynamic performance indicators of the inner-loop sliding mode controller are fed back to the outer-loop reinforcement learning agent in real time, guiding the adaptive adjustment of impedance parameters. Simultaneously, force / torque sensors detect the robotic arm's interactive power, and an energy tank mechanism is used to constrain the energy output of the reinforcement learning, preventing energy overshoot and system instability during training and execution. This method achieves force / position hybrid control performance while maintaining the robotic arm's compliance, safety, and energy stability in complex or unknown environments, improving the robustness and control accuracy of the robotic arm's interaction with the environment, and forming a comprehensive control closed loop with dynamic performance constraints, energy constraints, and adaptive learning.

The invention relates to the technical field of data processing, in particular to a secondary circuit defect intelligent detection method based on infrared temperature measurement, which comprises the following steps of: acquiring a temperature data sequence of a secondary circuit, acquiring an initial detrending component in any internal loop iteration of STL decomposition on the temperature data sequence, and calculating the initial detrending component according to the initial detrending component; carrying out fast Fourier transform to obtain a frequency domain signal, and judging whether the initial detrending component has a clear periodic characteristic or not according to the energy distribution characteristic of the frequency domain signal; if the initial detrending component does not have a clear periodic characteristic, performing seasonal correction processing on the initial detrending component to obtain a corrected seasonal component, marking the initial detrending component as an uncorrected seasonal component, and obtaining a target residual component of any internal loop iteration according to the corrected seasonal component and the uncorrected seasonal component; and repeating the target residual component acquisition method to obtain the final residual component, thereby improving the accuracy of defect detection on the secondary loop.

The invention provides a control method and device for a network-forming type grid-connected converter. According to the output voltage stable value of the grid-connected converter under the two-phase rotating coordinate system and the current reference value of the filter inductor under the two-phase static coordinate system, the voltage and current inner loop control of the grid-connected converter is realized, the control performance of the grid-connected converter can be improved, and the stable operation of the grid-connected converter is ensured. According to the invention, the actual value of the output voltage of the grid-connected converter under the two-phase static coordinate system is calculated according to the actual value of the current of the filter inductor and the actual value of the voltage of the primary winding, so that the state feedback control of the grid-connected converter is realized, and the dynamic characteristics of the grid-connected converter can be improved. And the control dimension of the network construction type grid-connected converter can be effectively increased.

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.