93 results about "Harmonic control" patented technology

The invention discloses a self-adaptive harmonic current suppression method for harmonic waves of a photovoltaic inverter, which belongs to the technical field of power quality control of a power system and comprises the following steps of: compensating a control strategy through a self-adaptive harmonic component of the photovoltaic inverter by adopting a'detection-reverse injection 'framework; the difference between the residual apparent capacity of the inverter after fundamental wave power supply and the borne harmonic power is used as an adaptive quantity, and the total harmonic distortion rate of the grid-connected point is reduced to the maximum extent on the premise of no overload; the method comprises the following steps: firstly, constructing a real-time harmonic detector based on a cascade generalized integrator; secondly, an inverter impedance model is established from the aspect of impedance stability, and a control parameter stability boundary is determined; then, a self-adaptive harmonic control strategy is introduced into the single-inverter grid-connected system, and a reasonable parameter setting method is provided on the basis of considering stability limitation; afterwards, a capacity-matched harmonic power distribution algorithm is provided for a multi-inverter parallel system, and the efficiency and operation stability of a photovoltaic grid-connected power generation system are improved.

The invention provides a grid-side current harmonic suppression method and device for a motor driving system without an electrolytic capacitor. The method comprises the following steps: determining first and second bus voltage harmonics based on bus voltage obtained by sampling and inverter switching frequency; correcting the bus voltage according to the first bus voltage harmonic wave and the second bus voltage harmonic wave so as to determine a reconstructed bus voltage; according to the second bus voltage harmonic, the reconstructed bus voltage, an inverter output three-phase duty ratio and a motor three-phase current, first and second network side current harmonic regulation and control voltages are determined based on a self-defined closed-loop controller; and adopting a motor alpha-axis correction voltage and a motor beta-axis correction voltage determined according to the first and second grid-side current harmonic regulation and control voltages to participate in motor SVPWM modulation to output the three-phase duty ratio of an inverter so as to suppress grid-side input current harmonics. According to the method and the device, factors such as motor operation conditions, bus voltage harmonic waves and digital control delay are comprehensively considered, the quality of grid-side input electric energy is improved, and disturbance to machine-side rotating speed and torque is reduced.

The invention provides a photovoltaic inverter common-mode resonance suppression method and device and a storage medium. The method comprises the steps of obtaining resonance current data of a common-mode loop; determining a differential negative feedback control strategy of a common-mode loop based on the resonance current data and preset common-mode current data; determining a harmonic control strategy of the system according to the first voltage data of the DC unit and the second voltage data of the power grid; determining a pulse width modulation strategy of the system based on a differential negative feedback control strategy and / or a harmonic control strategy so as to suppress common-mode resonance generated during voltage fluctuation; according to the method, the problems of current oscillation and inverter damage caused by common-mode resonance are effectively solved by obtaining the common-mode loop resonance current data and adopting the differential negative feedback control strategy to suppress resonance frequency point oscillation, combining the harmonic control strategy to eliminate the alternating current component, and finally dynamically adjusting the pulse width modulation strategy; the method has the advantage of improving the stability and safety of the system.

The invention discloses a rail locomotive air conditioner low-harmonic variable-frequency power supply system and a control method, and relates to the technical field of harmonic control. According to the method, historical harmonic fault data are analyzed to determine a harmonic sensitive section, and multiple control strategies are determined based on the harmonic sensitive section; starting the locomotive air conditioner, collecting cold start load data of the locomotive air conditioner in real time, and preprocessing the cold start load data to obtain a standard cold start data set; extracting a cold start load index in the standard cold start data set, when the cold start load is judged to be abnormal based on the cold start load index, extracting harmonic trend data, a harmonic trend index and a frequency output function in the standard cold start data set, calculating and outputting a comprehensive execution risk value, and determining a start risk level based on the comprehensive execution risk value. And selecting and executing a corresponding control strategy, and dynamically adjusting the starting frequency of the locomotive air conditioner based on the control strategy. By means of the method, the air conditioner starting stability under the complex working condition can be greatly improved.

The invention discloses a power distribution system harmonic source positioning method based on subsystem division, and aims to improve the accuracy and anti-interference capability of harmonic source identification in a power distribution system. According to the method, firstly, an obtained voltage signal is preprocessed, frequency domain feature information is extracted, a subspace projection operator is constructed through singular value decomposition, and effective extraction of each harmonic component in the signal is achieved. Then, carrying out subsystem division on the power distribution system according to the position of the tail end measurement point, for each subsystem, respectively injecting simulated harmonic current into each candidate node by adopting a virtual harmonic injection method, and calculating the response of the node to the tail end voltage; and comparing a simulation result with a measured value, constructing an error vector, screening out a node with the minimum error as a backup harmonic source node, and finally positioning the harmonic source node through zero setting of a connection node and a correction strategy of the most downstream node. The method is suitable for a multi-node and multi-source coexistence large-scale power distribution network harmonic suppression scene.

The invention discloses a harmonic suppression method and system based on feedforward control and virtual impedance, and belongs to the field of electric energy quality control, and the method comprises the steps: constructing a harmonic extraction model based on the cascading of double third-order generalized integrators, and obtaining a voltage harmonic component based on the harmonic extraction model and real-time power grid data; based on a preset power outer loop control strategy, a preset voltage and current double closed loop control strategy, a preset harmonic voltage feed-forward control strategy and the voltage harmonic component, constructing a network construction type charging pile control model, and obtaining an initial output current; obtaining each virtual impedance based on the initial output current, the harmonic extraction model and the voltage harmonic component; and obtaining a harmonic suppression model based on each virtual impedance and the network construction type charging pile control model, so as to obtain a harmonic suppression output current based on the harmonic suppression model and the real-time power grid data. According to the harmonic suppression method and system based on feedforward control and virtual impedance provided by the invention, grid-connected output current harmonics controlled by a network-forming type charging pile are effectively suppressed.

The invention discloses a harmonic suppression and dynamic reactive compensation control method for an energy router, which is suitable for a micro-grid and a distributed energy access system. According to the method, three-phase current and voltage signals of an alternating current port of the energy router are collected, five-time and seven-time main harmonic components are extracted through fast Fourier transform, harmonic compensation current instructions equal in amplitude and opposite in phase are generated and injected into an inverter to be output, and active counteracting of main harmonics is achieved. Meanwhile, the bus voltage deviation and the change rate thereof are detected, a reactive current instruction is adjusted on line by adopting a fuzzy self-adaptive PI controller, rapid and smooth dynamic reactive compensation is realized, and the bus voltage is stabilized. Decoupling control of active / reactive and harmonic components is realized in combination with Park conversion, and virtual impedance is introduced to enhance system damping and harmonic suppression capabilities. Compared with the prior art, harmonic suppression and voltage support can be simultaneously realized under a single control framework, the response speed is high, the stability is high, and the method is suitable for high-performance grid-connected operation of the multi-port energy router.

The invention discloses a novel power grid harmonic compensation method and system based on harmonic responsibility division, and relates to the technical field of power grid harmonic compensation, and the method comprises the steps: collecting voltage and current signals at a common connection point of a power grid, and extracting each harmonic component from the voltage and current signals; based on each harmonic component, identifying harmonic impedance of a system side and a user side, and calculating a responsibility factor sequence corresponding to each harmonic; performing statistical analysis on the responsibility factor sequence in a preset time window to generate responsibility fluctuation entropy representing responsibility stability; dynamically correcting the compensation priority of each harmonic according to the responsibility factor and the responsibility fluctuation entropy corresponding to the responsibility factor; generating a harmonic compensation instruction of a non-user responsibility part according to the responsibility factor and the harmonic component after priority correction, and distributing available compensation capacity according to the priority when the capacity of a compensation device is limited; the method is applied to a system comprising a plurality of distributed power supplies with harmonic regulation and control capability.

The invention discloses an integrated intelligent power management system and a harmonic control method. The method comprises the following steps: acquiring analog signals of voltage and current; digital signal sequences of voltages and currents in the N power distribution nodes are generated; obtaining a K-order frequency domain harmonic component of each power distribution node; judging abnormal harmonic nodes; if the abnormal harmonic nodes exist in the N power distribution nodes, constructing a harmonic description matrix for abnormal harmonic source positioning; inputting the harmonic description matrix into a pre-trained abnormal harmonic source positioning model, and outputting an abnormal node identifier where an abnormal harmonic source is located; according to the method, the judgment of the abnormal harmonic nodes is converted from single-index passive alarm to multi-feature driven active identification, and the management level of a power system is improved.

The embodiment of the invention provides a harmonic control method and device of an electric power system and a storage medium, the electric power system comprises a converter for converting direct current into alternating current, and the method comprises the following steps: determining a frequency range of a resonance point of the electric power system; under the condition that the switching frequency of the converter falls into the frequency range, determining a target resonant frequency of the resonant point; determining the type and electrical parameters of a nonlinear device needing to be added by taking the target resonant frequency as an optimization target; and setting the non-linear device in the power system. According to the method, a relatively serious resonance point in a power system is identified, and the vibration frequency of the resonance point of the power system is changed in a mode of increasing a nonlinear device, so that the frequency point of an original resonance source in a circuit is avoided, and the harmonic problem in a specific scene is solved in a low-cost mode; and long-term stable operation of a power system can be ensured.

The application discloses a variable frequency device dead zone compensation method, which acquires real-time data of a load current, obtains characteristic harmonics of dead zone generated current according to the real-time data of the load current, inputs the characteristic harmonics after taking the opposite to a regulator, then obtains a characteristic harmonic control quantity, and finally obtains a compensation time point or a compensation amplitude of the dead zone compensation according to the characteristic harmonic control quantity. The application improves the precision of the dead zone compensation, further reduces the harmonics of the system, has low sensitivity to the load characteristic change, and does not need to acquire a special dead zone compensation table.

The application relates to a continuous inverse class-F power amplifier based on source harmonic phase difference control and belongs to the wireless communication field. The power amplifier uses a special source matching network to control a transistor gate waveform, the source matching network is composed of a DC blocking network, a bias network and a harmonic control network; under the condition of a continuous inverse class-F load impedance, the source matching network designed by the application controls the second harmonic phase difference value of the transistor input end by using a series ladder microstrip line to form a T-shaped structure, so that excellent efficiency can be obtained, the load impedance design space can be expanded, and the complexity of a load matching network can be reduced.

This invention discloses a high-efficiency power amplifier with extended harmonic modulation bandwidth and its modulation method. A harmonic control circuit unit is added to the input terminal of the final stage die of the power amplifier. The extended harmonic control unit includes a second harmonic modulation circuit and a first parasitic element of the power amplifier back hole. The second parasitic element of the source back hole of the final stage transistor participates in modulation. Considering the parasitic effect of the power amplifier and the back hole at the source of the die, the harmonic modulation bandwidth is further widened by adjusting the harmonic control circuit unit, which effectively improves the working efficiency of the amplifier.

The invention relates to the technical field of power distribution cabinet internal harmonic control, in particular to a power distribution cabinet harmonic suppression method based on multi-source data fusion. By extracting amplitude and phase information at each harmonic frequency point, branch equivalent admittance is calculated, and an admittance distribution state is formed; judging an abnormal branch with admittance deviation at each frequency point, and establishing a corresponding relation between the adjustable electrical parameters and the admittance deviation; in the operation process of the power distribution cabinet, the admittance distribution state and the abnormal branch set are periodically updated, the equivalent admittance of the target branch is dynamically adjusted according to the corresponding relation, and the distribution of the harmonic current among the branches is changed; through the method, the harmonic peak value and the multi-node superposition effect in the power distribution cabinet can be actively reduced, online operation under the condition of multi-frequency and multi-node load fluctuation is adapted, harmonic flow direction reconstruction is achieved on the premise that complex filtering or hardware devices are not added, and the electric energy quality and the system stability of the power distribution cabinet are improved.

The present disclosure relates to a 5G or 6G communication system for supporting a higher data transmission rate, and a class-F amplifier (500) according to an embodiment of the present disclosure may comprise: an input matching network (IMN) (510) including an input harmonic tuning network (511) and an input fundamental matching network (512); a power amplifier (PA) (520) electrically connected to the input matching network (510); and a class-F output matching network (F-OMN) (530) electrically connected to the power amplifier (520).

The invention discloses a harmonic collaborative suppression method for grid connection of a new energy power station, which relates to the field of grid-connected harmonic control, and comprises the following steps of: acquiring voltage and current instantaneous values of a grid-connected side of the new energy power station and output power and switching frequency of a photovoltaic inverter and a wind power converter; constructing a mapping model of the dynamic characteristics, the amplitude and the time of each harmonic source; according to the method, dynamic characteristics of each harmonic source are captured through time domain and frequency domain combined analysis, harmonic transmission paths and coupling strength are quantified by combining power grid impedance and load fluctuation parameters, and suppression priorities are reasonably divided according to harmonic contribution degree and tolerance margin.

The invention provides a harmonic current control method, a controller and an inverter, and is applied to the technical field of inverters, and the method comprises the steps: taking a half switching period of the inverter as a sampling period, carrying out the sampling of the output current of the inverter, obtaining a first sampling result corresponding to the current sampling period and a second sampling result corresponding to the last sampling period, the current sampling period is adjacent to the previous sampling period, and the determination of the target sampling current multiplexes the sampling result of the previous sampling period, so that the harmonic control signal is generated based on the target sampling current. Therefore, the sampling result in the complete switching period duration is obtained in the half switching period, the duration for determining the target sampling current is effectively shortened, the delay duration for generating the harmonic control signal is further shortened, the timeliness of the harmonic control process is ensured, and the stability of the harmonic control process and the harmonic current suppression effect are improved.

The invention relates to the technical field of harmonic treatment of charging equipment, and discloses a charging pile filtering treatment device which comprises a filtering treatment device body, the bottom of the filtering treatment device body extends downwards to form a mounting cavity, a water cooling machine is arranged in the mounting cavity, and a cooling pipe of the water cooling machine extends into the filtering treatment device body. After being coiled in the water cooling pipe, the water cooling pipe penetrates out and flows back to the water cooling machine; the filtering treatment device comprises a filtering treatment device body, the outer wall of the filtering treatment device body is provided with a plurality of heat dissipation pipes communicated with the interior of the filtering treatment device body, and an outlet of each heat dissipation pipe is formed in the top of one end located in the filtering treatment device body and is perpendicular to an inlet formed in the corresponding heat dissipation pipe; the device can adapt to an outdoor installation environment, the probability that rainwater permeates into the device is avoided, efficient heat dissipation can be achieved, and the application reliability and effectiveness of the device in a new energy automobile charging pile scene are guaranteed.

To provide novel types, structures, and arrangments of capacitor networks for harmonic control and the other purpose.SOLUTION: An integrated device includes: a capacitor network; and one or more power devices. The capacitor network includes: a bond pad; and metal-insulation-metal (MIM) capacitors. The capacitor includes: a first metal layer; a second metal layer; an insulation layer between the first and second metal layers; and one or more substrate penetration vias. The first metal layer is connected to the bond pad, and the second metal layer is connected to a ground plane on a bottom side of a substrate by the vias. A plurality of capacitors for an adaptive electrostatic capacity can be arranged around the bond pad in the capacitor network. A matching network in the integrated device can incorporate the capacitor network to reduce a loss, provides better harmonic termination, and achieve better phase alignment of the power devices.SELECTED DRAWING: Figure 2

This invention discloses an ultrawide, high-efficiency inverse Class-F power amplifier based on an elliptic low-pass filter matching network. The gate DC bias network provides the gate bias voltage required for the power amplifier transistor to operate; the drain DC bias network provides the drain bias voltage required for the power amplifier transistor to operate; the input impedance matching network includes a microstrip line, a DC blocking capacitor, and an RC parallel circuit; the output impedance matching network includes a harmonic control network and an elliptic low-pass filter matching network. The harmonic control network selects two frequency points outside the passband for second harmonic control; the elliptic low-pass filter matching network is based on an improved sixth-order Chebyshev low-pass filter, generating two transmission zeros outside the operating frequency band to achieve the conversion from fundamental impedance to second harmonic impedance. This invention enables the power amplifier to achieve high efficiency and high gain within a bandwidth exceeding five harmonics.

New types, structures, and arrangements of capacitor networks for harmonic control and other purposes are described. An example integrated device package includes a power transistor formed on a first substrate, a metal-insulator-metal (MIM) capacitor network formed on a second substrate, bond wires electrically coupled between a bond pad of the second substrate and a gate contact of the power transistor, a metal-oxide-semiconductor (MOS) capacitor network formed on a third substrate, and bond wires electrically coupled between a bond pad of the third substrate and the gate contact of the power transistor. The MIM capacitor network can include a MIM capacitor, with a first metal layer of the MIM capacitor being electrically coupled to the bond pad of the second substrate and a second metal layer of the MIM capacitor being electrically coupled to a ground plane on a bottom side of the second substrate.

The application provides a control system and a control method of an LLC resonant induction heating power supply. The LLC resonant induction heating power supply heats a load through a half-bridge inverter circuit. The control system comprises a modulation unit and an odd harmonic control unit. The modulation unit is used to determine a target modulation index and a fundamental frequency, and to realize an output frequency adjustable high-frequency alternating square wave by controlling the switching of each power device of the half-bridge inverter circuit. The waveform of the high-frequency alternating square wave has a half-wave symmetric structure with a fundamental period as a cycle. The odd harmonic control unit is used to predict an optimal switching angle combination of each power device under the condition of meeting an odd harmonic suppression target. The modulation unit generates a modulation signal for controlling the switching of each power device based on the optimal switching angle combination. The application can significantly improve the harmonic suppression effect of a high-frequency induction heating power supply under a dynamic load.

The application discloses an inverter adaptive harmonic control method, medium and equipment; the method steps are as follows: real-time sampling of the input voltage of each MPPT branch, and dividing into multiple voltage clusters according to the proximity of voltage amplitude; performing phase coordination on each MPPT branch in the same voltage cluster to obtain a controllable amplitude and direction sub-ripple vector; overall planning the sub-ripple vectors of all voltage clusters, adjusting the intra-cluster and inter-cluster phase relationship of the voltage clusters multiple times through an iterative algorithm, so that each sub-ripple vector gradually offsets each other; generating a modulation signal for driving each MPPT branch according to the optimal phase set output by the iterative algorithm. The medium and equipment are used for implementing the above method. The application has the beneficial effects that: the application performs zoned collaborative control on each MPPT branch, can effectively suppress the ripple influence caused by each MPPT branch on the bus under the condition of unbalanced output voltage, and improves the power quality and equipment life.

The application provides an affine harmonic current calculation method considering new energy harmonic emission characteristics, comprising the following steps: step 1: considering the influence of meteorological conditions, dead zone effect, control time delay and background harmonic, an affine model of harmonic sources of wind power and photovoltaic is established to accurately describe the uncertain harmonic emission characteristics of wind power and photovoltaic; step 2: according to the power characteristics of new energy power generation under the influence of different reactive power control strategies, an affine model of the machine-grid interface of new energy power generation is constructed; step 3: an affine Ybus Gauss iteration algorithm based on reactive power prediction-correction is used to solve the fundamental wave current of the power grid to obtain the operating point of the harmonic source; step 4: an affine overrelaxation iteration method is used to solve the harmonic current equation, and the interval range of the harmonic state quantity is obtained through the alternating iteration of the fundamental wave and the harmonic; the application of the technical scheme can accurately solve the uncertain harmonic current of the new energy power grid, thereby providing a reference for the grid connection planning and harmonic control and suppression of new energy power generation.

The invention discloses an F-type high-power rectifying circuit based on admittance matching, and belongs to the field of microwave wireless energy transmission. The circuit comprises a dielectric substrate, an upper surface circuit structure and a grounding metal floor, wherein the upper surface circuit structure comprises a three-stage F-class harmonic network, an admittance matching structure, a direct current filtering structure, a 50-ohm bonding pad, a metal floor, a Schottky diode, a blocking capacitor, a load resistor and a grounding via hole. A novel three-level F-type harmonic network is adopted, the network can not only perform impedance control on second and third harmonics, but also perform impedance control on fourth harmonics, and the more multi-level harmonic control network can reduce the diode loss and further improve the rectification efficiency; in addition, a new technology based on admittance matching is adopted, impedance is converted into admittance, so that admittance of the parallel circuit can be directly added, the matching complexity of the parallel circuit can be reduced by matching the admittance, and the matching intuition is improved.

A motor control device is provided that is capable of both reducing the time required to design and adjust the amount of correction for each amplitude and phase according to response characteristics, and ensuring a torque ripple suppression effect. A motor control device 1 drives a motor 5 using an inverter 4. The motor control device 1 includes a harmonic control command value computer 8, which provides the first harmonic control command values ​​i*. dqh and φ* dqh from a torque command value τ* and an electrical angle θ e of the motor 5, a response compensator 9, the second harmonic control command values ​​i** dqh and φ** dqh calculated by performing response characteristic compensation on the first harmonic control command value i* dqhaccording to the speed of the motor 5, and a voltage command calculator 3 which provides a voltage command value v* dq based on a control command to output a torque of the torque command value τ* and the second harmonic control command values ​​i** dqh and φ** dqh calculated.

The invention relates to a harmonic control system, method and device of a variable-frequency power supply and a storage medium, the harmonic control system of the variable-frequency power supply comprises a power module, a main control module, a signal acquisition module and a filtering module, the main control module is connected with the power module, the signal acquisition module is connected with the main control module, and the filtering module is connected with the signal acquisition module. The power module is connected with the filtering module. Through the collaborative architecture of the main control module, the signal acquisition module, the power module and the filtering module, high-order harmonic interference can be effectively suppressed, it is ensured that the output voltage of the variable-frequency power supply is stable, the waveform is smooth, the total harmonic distortion (THD) is strictly controlled within 2%, and the strict requirements of precise industrial equipment, power electronic systems and the like for the quality of the power supply are met.

The invention provides a power amplifier and a harmonic control method. The power amplifier comprises an input matching circuit, a power amplifying circuit, a harmonic control circuit and an output matching circuit, and the harmonic control circuit comprises a switch control sub-circuit, a first harmonic control sub-circuit and a second harmonic control sub-circuit. A switching control sub-circuit for adjusting a first harmonic control sub-circuit and a second harmonic control sub-circuit according to a fundamental frequency of an input signal to resonate the first harmonic control sub-circuit at even harmonics in a first power signal and to combine the first harmonic control sub-circuit and the second harmonic control sub-circuit together at a first power an odd harmonic in the signal resonates to convert the first power signal into a second power signal; the overlapping time between the voltage waveform and the current waveform in the second power signal is smaller than or equal to a preset threshold value. According to the invention, even harmonics and odd harmonics of different frequency bands in the bandwidth can be controlled by the power amplifier.

The invention relates to the technical field of power electronics, particularly discloses a harmonic prediction control method for a three-phase four-wire inverter under a high-harmonic power grid, and aims to solve the problems of dynamic response lag, weak zero-sequence harmonic suppression and multi-target control conflict in the prior art under high harmonic distortion, power grid frequency deviation and load sudden change. The method comprises the steps of signal acquisition and coordinate transformation; carrying out extended state observation and adaptive harmonic wave identification; generating four vectors and constructing a multi-target cost function; tetrahedron interval judgment and duty ratio optimization; and delay compensation and compound control are executed. According to the technical scheme, accurate tracking of fundamental waves and cooperative suppression of full-band harmonic waves are achieved, output can still be controlled within 3% when the total harmonic distortion rate of power grid current reaches up to 25%, and the dynamic response speed, the frequency robustness and the engineering practicability are remarkably improved.