45results about "Active power filtering" patented technology

The invention discloses an active power filter residual life evaluation method, system and device, a medium and a product, and the method comprises the steps: constructing a failure degradation model of a DC side capacitor of an active power filter and a failure degradation model of an IGBT power module through a Wiener process; determining an edge cumulative distribution function of the direct-current side capacitor and an edge cumulative distribution function of the IGBT power module, coupling the edge cumulative distribution function of the direct-current side capacitor and the edge cumulative distribution function of the IGBT power module by using a Copula function, and based on a joint degradation probability distribution model, performing Monte Carlo simulation to obtain a degradation probability distribution model. According to the method, the degradation tracks of the direct current side capacitor and the IGBT power module from the starting moment to the future moment are simulated, and when any one degradation track passes through the failure threshold value, the latest moment is determined as the degradation moment, so that the residual life estimation value of the active power filter is determined, and the precision of residual life estimation is improved.

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 utility model discloses power electronics equipment's test and debugging technical field relates to a kind of debugging device for active filter;Including cabinet;The cabinet inside is provided with voltage regulator, control module and power module;The control module is located above voltage regulator;The cabinet side is provided with aviation plug;The power module and voltage regulator are electrically connected;The voltage regulator and aviation plug are electrically connected;The aviation plug is electrically connected with active filter and control module respectively;The active filter and mutual inductor are electrically connected;The mutual inductor and control module are electrically connected;The voltage regulator and intelligent electric meter are electrically connected;The intelligent electric meter and control module and electrically connected.The utility model can realize the quick power-on test of active filter, parameter adjustment and performance verification.

A control system including a power grid configured to supply a grid voltage, a filter capacitor and a filter inductor each connected in parallel to the power grid, a filter current meter connected in series to the filter inductor, an active power filter connected to the filter current meter, a nonlinear load connected in series to the power grid, and a modulated model predictive controller (MMPC) configured to generate a control signal for operating the active power filter.

The application discloses a control method and system of a hybrid active power filter and a storage medium, wherein the inductance value and the capacitance value of a passive power filter are taken as inputs of a particle swarm optimization method to obtain optimized inductance value and capacitance value; when the harmonic number filtered by the passive power filter is the same as the harmonic number filtered by the active power filter, the active power filter is equivalent to a virtual LC filter with the same structure as the passive power filter; otherwise, the active power filter is equivalent to a virtual resistor; a harmonic compensation current reference value of the active power filter is obtained; the harmonic compensation current reference value and a reactive compensation current reference value are superimposed to obtain a total reference current of the active power filter, and the total reference current is taken as an input of a proportional resonant controller, and the output of the proportional resonant controller is PWM modulated. The application eliminates the harmonic current amplification problem of the passive power filter and improves the stability and compensation performance of the power system.

Techniques are described for testing whether an end effector, or component thereof, is correctly or incorrectly installed to a manipulation system. In an example, a manipulation system can include a manipulator arm configured to receive an end effector having a first moveable jaw, a transducer configured to provide first effort information of the end effector as the end effector moves, and a processor configured to provide a command signal to effect a first test move of the first moveable jaw, and to provide an installation status of the end effector using the first effort information of the first test move.

The invention relates to a self-adaptive prediction control method and system for an LCL type active power filter, and the method comprises the following steps: introducing a self-adaptive weight, dynamically fusing a power supply current frequency domain detection component and a load current time domain detection component, and fusing frequency domain high-precision detection and time domain quick response detection through the self-adaptive weight. The limitation of a single detection mode is overcome, and the compensation precision and the response speed can be improved respectively under the steady-state and transient-state working conditions; the reference current is predicted in advance according to the digital control delay step size, an inverter voltage instruction is calculated in a reverse recursive mode according to the reference current, the inverter voltage instruction is corrected to obtain a final instruction, and the final instruction drives a voltage source inverter to output compensation current; according to the compensation current tracking error and the load power change rate, the self-adaptive weight, the outer ring prediction step length and the self-adaptive virtual damping coefficient are dynamically adjusted, and the overall adaptability of the system to complex working conditions is enhanced.

The invention discloses a network construction type high-precision active power filter control method, an active power filter comprises a power outer loop control unit and a voltage and current inner loop control unit, and the power outer loop control unit comprises an active power outer loop and a reactive power outer loop. The voltage and current inner loop control unit comprises an AC voltage loop and an AC current loop, and the control method provides a control loop architecture for three-phase three-wire and three-phase four-wire high-precision active power filters, and comprises two-phase DQ closed-loop control and three-phase independent closed-loop control of grid-side harmonic current; through a mode of generating a harmonic voltage instruction through a harmonic current closed loop, the impedance of a harmonic current frequency band is remodeled while high-precision compensation of the harmonic current is realized; high-precision compensation of harmonic current is realized through a network construction control technology; while high-precision compensation is realized, port harmonic impedance is remodeled, so that the adaptability of a load and a power grid is higher.

The invention discloses an active filtering and reactive compensation adaptive control method, and belongs to the technical field of rail transit power systems. The method comprises the steps that S1, real-time monitoring is conducted, an active power filter (APF) is connected into a power grid and controlled by a DSP controller to be switched between an operation mode and a shutdown mode, and the DSP controller is electrically connected with a communication interface; s2, condition monitoring is triggered, switching between an operation mode and a shutdown mode is achieved, and the switching modes comprise automatic switching according to the rail transit operation time period and remote switching by receiving an instruction through a communication interface of a DSP controller; s3, dual-mode purification of electric energy quality: in an operation mode, an active power filter APF starts a harmonic compensation function and dynamically tracks a target power factor in a reactive mode; and in the shutdown mode, the active power filter APF closes the harmonic compensation function and outputs fixed inductive reactive power. The operation time period of the rail transit is matched with the two modes of the active power filter APF, so that the self-adaptive control of the electric energy quality can be realized according to the operation condition of the rail transit.

The invention discloses a three-level active power filter direct-current bus capacitor design method and system, and belongs to the field of power electronic device design, and the method comprises the steps: determining the minimum capacity demand of a direct-current bus capacitor according to the rated power of a system and the working condition of a power grid; respectively calculating effective values of the triple frequency ripple current and the high-frequency ripple current related to the switching frequency by adopting a decomposition analysis method of a low-frequency component and a high-frequency component; by decomposing the low-frequency ripple current and the high-frequency ripple current, a ripple current mathematical model is established to analyze the bearing capacity of the capacitor for ripple current of different frequencies, and model selection and parallel configuration of the capacitor are obtained; carrying out the structure and heat dissipation design of the capacitor; evaluating the service life of the capacitor, and designing a maintenance mechanism in combination with a service life evaluation result; simulation verification is carried out, the current ripple control effect is tested firstly, and then the system stability is verified. The method optimizes the parallel configuration of the capacitors, and improves the dynamic response performance and long-term operation reliability of the system.

The utility model provides a wall-mounted hybrid APF device, which relates to the technical field of hybrid APF devices, and comprises a wall and a fixed plate fixedly mounted on the wall, an L-shaped sliding block is arranged in the fixed plate, a mechanism used for adjusting the L-shaped sliding block is arranged in the fixed plate, a group of mounting grooves are formed in the top end of the L-shaped sliding block, and the L-shaped sliding block is arranged in the mounting grooves. And one side of the L-shaped sliding block penetrates through the sliding groove to be provided with a device body, one side of the device body is connected and provided with a set of L-shaped connecting plates, the set of L-shaped connecting plates are installed in the set of installing grooves, and connecting structures are arranged at the attaching positions of the L-shaped connecting plates and the installing grooves. According to the device, the height of the device body can be adjusted according to the needs of workers, the connecting efficiency of the device body and external elements is indirectly improved, inconvenience brought to the workers by height fixation is avoided, the workers do not need to adjust the height of the device body to frequently open holes in the wall for installation, and the installation efficiency is improved. And due to the design, the practicability is greatly improved.

The application discloses a model prediction control method of a dual-module active power filter parallel system in the technical field of active power filtering, calculates a compensation current prediction value based on 64 synthesized voltage vectors and three-phase grid voltages and three-phase compensation currents, calculates 64 evaluation values through evaluation of a value function, and controls two inverters according to a switch state corresponding to a synthesized voltage vector corresponding to a minimum value in the 64 evaluation values; the active power filter based on the parallel three-phase inverters of the common DC bus is discretely mathematically modeled as a six-bridge-arm inverter system, the three-phase harmonic compensation currents of the two inverters are predicted, and the 64 synthesized voltage vectors of the parallel three-phase inverters are iteratively optimized through evaluation of the value function, so that the global optimization of the circulating current between the two inverters is realized, the circulating current of the parallel inverters is effectively inhibited, and the harmonic compensation accuracy and system efficiency of the active power filter are improved.

The application relates to the technical field of power grid electric energy, in particular to a passive power filter for a power grid electric energy quality active defense system, which comprises an outer box body, a filter unit and a bottom control frame are arranged in the outer box body, the bottom control frame is connected below the filter unit, the bottom control frame comprises a bracket, a walking frame, a heat conduction plate and a thermal control device, the bracket is fixed on the inner wall of the outer box body, the walking frame is connected above the bracket, and the heat conduction plate is fixed above the walking frame, the design of the bottom control frame realizes the multi-control effect on the filter unit, the filter unit can be conveniently disassembled and assembled on the outer box body, and the quality of power maintenance work is improved; in addition, a mechanical temperature control real-time monitoring device is arranged in the walking frame, compared with the temperature monitoring of electronic instruments in the traditional technology, the mechanical temperature control device can directly reduce the economic investment cost in the power grid electric energy by replacing the electronic instruments.

A cascaded multilevel converter is disclosed. The converter comprises a plurality of modules coupled together to form a limb, each of the modules comprising a switching circuit and a DC link for providing a DC voltage to the switching circuit. The converter further comprises a controller for controlling the switching circuit of each module to generate an AC voltage in the limb, wherein the controller is configured to determine, for each module, a voltage across a capacitor of the DC link of the module, determine, for each module, a reference power value for charging the capacitor of the DC link of the module to a reference voltage value of the module, determine a common reference AC current value for an AC current in the limb from the plurality of reference power values of the plurality of modules, determine a common reference AC voltage value for an AC voltage in the limb from the common reference AC current value, determine, for each module, a reference AC voltage value using the common reference AC voltage value and the reference power value of the module, and generate a pulse width modulation signal for controlling the switching circuit of each module from the reference AC voltage value of the module and the voltage across the capacitor of the module.

The invention relates to the field of active power filters, and discloses an APF active power filter with a high heat dissipation function, the APF active power filter comprises a filter body and a heat dissipation assembly, the heat dissipation assembly comprises a heat conduction unit, a liquid storage unit and an air cooling unit, the heat conduction unit comprises a heat conduction box, the interior of the heat conduction box is hollow, and an inlet hole and an outlet hole are formed in the upper surface of the heat conduction box; an outlet pipe is arranged at the upper orifice of the outlet hole, an inlet pipe is arranged at the upper orifice of the inlet hole, the pipe wall of the inlet pipe is divided into two sections which are coaxial and unequal in diameter along the axial lead direction, the two sections are respectively an upper section and a lower section, the pipe diameter of the upper section is larger than that of the lower section, so that a step surface is formed, and a core pipe is arranged at the cavity bottom of the heat conduction box; the upper end of the core pipe is closed and located in the lower section of the inlet pipe, a piston is sleeved with the core pipe, a thermal expansion medium is stored in the space below the piston, a connecting rod is arranged on the upper surface of the piston, the upper end of the connecting rod extends out of the core pipe and is provided with a sealing plate, a spring is arranged between the piston and the upper end of the core pipe, and the sealing plate is attached to the step face at the beginning.

The application provides a power quality comprehensive treatment system based on APF and SVG collaborative control, belongs to the intelligent power grid industry and the power quality comprehensive treatment technical field, and comprises the following steps: acquiring power grid current signals and voltage signals, detecting harmonic components and voltage deviations through a harmonic detection module; adopting a collaborative decision controller to determine a compensation strategy according to the harmonic components and the voltage deviations, and distributing compensation tasks of active power filter channels and static var generator channels; generating harmonic compensation currents through the active power filter channels to suppress high-frequency harmonics; generating reactive compensation currents through the static var generator channels to stabilize voltage fluctuations; and filtering the compensation currents through a filtering module and outputting to the power grid. The power quality comprehensive treatment system can effectively suppress power grid harmonics, stabilize voltage fluctuations, improve power quality, and is suitable for complex power grid environments.

A single-phase voltage source inverter and method including a main inverter circuit connected to an active power filter circuit, the main inverter circuit comprising an H-bridge circuit comprising a first leg and a second leg, the first leg comprising a first switch, a second switch, and the second leg comprising a third switch and a fourth switch, the active power filter circuit comprising a third leg comprising a fifth switch and a sixth switch, the main inverter circuit connected to a secondary side of a high frequency transformer and a grid filter in series, and adapted to be connected to an AC load, a primary of the high frequency transformer and a capacitor connected in series to the active power filter leg and an H-bridge leg.

The invention discloses a capacity calculation method, device and equipment of an active power filter and a storage medium, and relates to the technical field of power harmonic compensation. Background harmonic voltage historical data, grid structure information, main equipment parameters and operation mode information of a land power grid are acquired; according to the grid structure information, the main equipment parameters and the operation mode information, calculating the equivalent impedance of the onshore power grid in offshore wind power access; according to the impedance of the offshore wind power system and the equivalent impedance, determining the harmonic frequency with the harmonic amplification risk in the background harmonic voltage historical data; calculating an equivalent harmonic current according to the equivalent impedance and the background harmonic voltage historical data corresponding to the harmonic frequency; the compensation capacity of the active power filter is calculated according to the equivalent harmonic current, accurate calculation of the APF compensation capacity is completed, and the economical efficiency of APF capacity configuration is improved.

An active power conversion apparatus (APCA) estimates a grid frequency estimation of an electric grid connected to the APCA. The APCA includes a controller for receiving measurements of at least one phase current between the APCA, and the electric grid. The controller converts the at least one phase current to at least one synchronous reference frame, and determines direct and quadrature current references to be used in the grid frequency estimation. The controller determines a use of frequency estimation as a manipulated variable that forces to zero at least one of the average values of current error signals.

The present disclosure provides a power quality compensation device and a control method thereof. The power quality compensation device is electrically connected to a power grid and a non-linear load, and includes a current controller, a converter, a ripple predictor, a processing unit, and a voltage controller. The current controller receives an instruction current and outputs a switching control signal. The converter outputs an output current and an actual DC bus voltage according to the switching control signal. The ripple predictor receives an intermediate voltage and a first current and outputs a predicted ripple voltage, wherein the intermediate voltage is a voltage at a common connection point between the power grid and the non-linear load. The processing unit outputs a processing result according to the actual DC bus voltage, the predicted ripple voltage, and a reference DC bus voltage. The voltage controller receives the processing result and outputs a voltage control signal to the current controller.

The invention discloses a control method of a network-forming type active filter, the active filter comprises a power outer loop control unit and a voltage and current inner loop control unit, and the power outer loop control unit comprises a direct current bus voltage loop, an active power outer loop and a reactive power outer loop. The voltage and current inner loop control unit comprises an AC voltage loop and an AC current loop. The active filter is operated in a network construction mode, and the voltage source characteristic of the active filter can suppress the source load resonance problem to the greatest extent; for a balanced load and an unbalanced load, an instantaneous reactive power theory and a TTA harmonic detection algorithm are respectively adopted to obtain a harmonic voltage instruction, so that load-side harmonic suppression is realized; a harmonic voltage instruction is obtained by carrying out harmonic detection calculation on load current, and load side harmonic treatment is carried out, so that the function of actively carrying out harmonic treatment on the network construction type converter is realized; the harmonic impedance characteristic reconstruction of the active filter is realized through harmonic voltage source control, and the problem of multi-machine parallel resonance can be effectively solved.

The invention provides an active power filter harmonic suppression system based on single-cycle dual-carrier comparison control, which comprises an active power filter, a measurement module, a harmonic current extraction module and a control unit, and is characterized in that the control unit comprises a frequency calculation module, a self-adaptive resonance control module, a dual-carrier comparator and a PWM (Pulse Width Modulation) module; the self-adaptive resonance control module generates a reference voltage signal based on the real-time fundamental frequency of the power grid calculated by the frequency calculation module, and the dual-carrier comparator compares the reference voltage signal with a rising type triangular carrier signal and a falling type triangular carrier signal at the same time in each switching period. And the PWM module converts the comparison result into a PWM signal for driving each switching device in the active power filter through the synergistic effect of the D trigger and the logic gate circuit. According to the method, the problems of compensation failure and insufficient multi-band harmonic collaborative suppression caused by frequency mismatch in a traditional method are solved, and the system efficiency, the dynamic performance and the working condition adaptation are remarkably improved.

The present application relates to a kind of LCL type active power filter composite active damping optimization control method, including inverter side current active damping optimization control and grid voltage active damping optimization control.The beneficial effects of the present application are: the present application obtains the wide active damping boundary close to Nyquist frequency using the inverter side current active damping optimization control based on cascaded resonant controller, and has accurate adjustment ability to fundamental current component, to ensure the stable operation of system when grid impedance fluctuates in a large range.In addition, the present application also uses the grid voltage active damping optimization control based on weighted proportional order reduction generalized integrator, solves the potential instability risk caused by the phase margin reduction of active power filter harmonic control unit due to large grid impedance.In summary, the present application effectively improves the weak grid adaptability of LCL type active power filter.

This invention discloses an APF control method with frequency adaptation under grid voltage imbalance. The inner loop (voltage loop) uses PI control to stabilize the DC bus voltage, achieving stable energy exchange between the two sides of the converter. The outer loop (current loop) employs a composite control algorithm combining proportional-integral (PI), proportional-complex-integral (PCI), and proportional-resonant (PR) control to achieve precise control of the compensation current. When the grid voltage is balanced, only PI plus PCI control is used, resulting in a large stability margin and fast dynamic response. When the grid voltage is unbalanced, a full-pass filter separates the reference signal into positive and negative sequences. The positive sequence component still uses PI plus PCI control, while the negative sequence component uses PI plus PR control, addressing the poor stability of single PCI control under grid voltage imbalance. A frequency-locked loop is introduced into the system to track and control the grid frequency in real time, improving current control accuracy and simplifying the computational complexity of the control algorithm. This method is applicable to other three-phase inverter control systems.

This invention belongs to the field of power electronics technology and provides a method and system for improving the harmonic transient stability of a grid-type active power filter. The method involves integrating the deviation between the active power reference command and the actual measured active power value after droop control to obtain the power angle. The power angle is then added to the grid-side harmonic phase to generate a harmonic voltage phase command. The deviation between the reactive power reference command and the actual measured reactive power value is obtained through PI control to obtain the voltage deviation. This voltage deviation is then summed with the amplitude of a specified harmonic voltage on the grid side to generate a harmonic voltage amplitude command. Using the harmonic voltage amplitude command as the d-axis reference and 0 as the q-axis reference, the deviation is obtained by subtracting the d-axis and q-axis references from the harmonic voltages on the d-axis and q-axis, respectively. The dq components of the harmonic voltage reference are then obtained through PI control. This invention can improve the safety of power grid operation.

Techniques are described for testing whether an end effector, or component thereof, is correctly or incorrectly installed to a manipulation system. In an example, a manipulation system can include a manipulator arm configured to receive an end effector having a first moveable jaw, a transducer configured to provide first effort information of the end effector as the end effector moves, and a processor configured to provide a command signal to effect a first test move of the first moveable jaw, and to provide an installation status of the end effector using the first effort information of the first test move.

A method and system for controlling a photovoltaic solar power generation source operatively coupled to a power grid system at a point of common coupling (PCC) to perform a plurality of dynamic reactive power control based functions including: reactive power set point control, power factor control, and voltage control, when its primary energy source is not available, and available. Voltage control may also prevent PCC voltage from violating a voltage limit caused by real power generation from itself or by real power generation from an additional distributed power generation source operatively connected to said power grid system, or by both. Controlling a battery energy storage based distributed power generation source operatively coupled to a power grid system at a PCC to perform reactive power set point control, power factor control, and voltage control, during both the conditions when its primary energy source is not available, and available is also provided.

The utility model discloses an active power filter capable of rapidly dissipating heat, which belongs to the technical field of heat dissipation of active power filters, and is characterized by comprising a bearing frame, a cabinet type active power filter body is arranged at the top of the bearing frame, and an auxiliary mechanism is arranged at the bottom of the inner side of the cabinet type active power filter body. The auxiliary mechanism comprises a bearing assembly and a heat dissipation assembly, the bearing assembly is arranged at the bottom of the cabinet type active power filter body, the heat dissipation assembly is arranged on the inner side of the bearing assembly, and the bearing assembly and the heat dissipation assembly are arranged so that the bearing assembly can fix and protect the heat dissipation assembly; meanwhile, the heat dissipation assembly can be rapidly moved out of the cabinet type active power filter body through the bearing assembly so as to be convenient for a user to maintain, and the heat dissipation assembly can rapidly exhaust hot air in the cabinet type active power filter body and can be in contact with airflow to disperse insect repelling smell to the periphery of the cabinet type active power filter body to repel insects.

A control device (100) for an active filter (80) connected in parallel with a load (4b) at an installation point (4a) with respect to an AC power supply (2) provided in a power system includes a harmonic voltage detector (7) to detect an m-order harmonic voltage (m is an integer not less than two) included in a voltage of the installation point (4a), a phase corrector (9) to correct a phase of the detected m-order harmonic voltage in accordance with whether an m-order harmonic impedance when an AC power supply (2) side is seen from the installation point (4a) is capacitive or inductive, a command value generator (10) to generate a first compensation command value for compensating for the m-order harmonic voltage included in the voltage of the installation point (4a) based on the m-order harmonic voltage after the correction, and an output controller (18) to control an output of the active filter (80) based on a first compensation command value.

The invention discloses an active power filter based on voltage control, the active power filter is provided with a filter and a controller, the active power filter is connected to a point of common coupling (PCC) of a power grid and a harmonic load through the filter, a voltage monitoring point is arranged on the power grid side of the point of common coupling (PCC), and the voltage monitoring point is connected with the controller. The controller detects the voltage of a point of common coupling (PCC) of the power grid and the harmonic load and controls the harmonic component to 0, and at the moment, the active power filter is equivalently short-circuited at the harmonic frequency. Voltage distortion caused by local harmonic current can be compensated, and local voltage distortion caused by background power grid voltage distortion can be effectively suppressed. Compared with a traditional APF, the control target of the scheme is more direct, and the overall improvement effect on the electric energy quality is more remarkable.