94 results about "Voltage distortion" patented technology

The invention relates to the technical field of online calibration, in particular to a multi-parameter fusion intelligent electric energy meter online calibration method and system, and the method comprises the following steps: collecting voltage waveforms, current harmonics and active power data, dividing windows, calculating a covariance matrix, and generating a feature set; a power factor curvature extreme value and a temperature inflection point offset are analyzed to generate an interference identifier, current density distribution and a voltage distortion spectrum are jointly analyzed to extract a harmonic energy ratio to generate a feature vector, and phase compensation is performed on a pulse sequence to generate a calibration instruction set. According to the method, the covariance matrix is constructed by synchronously collecting voltage and current power parameters, the abnormal mark section is generated by combining the temperature change and the covariance difference value, the environment disturbance and the real deviation are effectively distinguished, and the temperature hysteresis effect is identified through the power factor curvature extreme value and the temperature inflection point offset. And combining current density and voltage distortion spectrum analysis to extract a fundamental wave and harmonic wave energy ratio, establishing a composite calibration reference, and dynamically adjusting a pulse duty ratio to realize harmonic wave energy compensation.

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

The invention relates to the technical field of electrical equipment monitoring, in particular to a power distribution equipment state intelligent diagnosis system and method, and the system comprises a current fluctuation detection module, a voltage stability evaluation module, a heat effect diffusion analysis module, a fault point positioning module and an equipment state evaluation module. According to the invention, through extracting current change characteristics of key nodes and judging continuity of fluctuation differences, rapid identification of current anomalies can be realized, a voltage distortion region and a distribution range thereof can be positioned in combination with phase deviation and symmetry change of voltage waveforms, and the current anomalies can be identified based on a temperature gradient path and jump point screening. A hot spot diffusion trend and a thermal disturbance boundary can be described, morphological analysis and coordinate labeling are performed on the basis of multiple fault areas, multi-point concurrent positioning is realized, association between thermal disturbance and connection defects is identified in combination with temperature difference and current path change characteristics, fault diffusion trends and state disturbance blocks can be accurately presented, and the accuracy of fault diagnosis is improved. And the power distribution state identification and intervention efficiency is improved.

The invention discloses a GaN totem-pole bridgeless PFC converter harmonic suppression method based on adaptive virtual admittance, and belongs to the technical field of converter control. The invention aims to solve the problem that LC resonance in a GaN totem-pole bridgeless PFC converter in a wide load range causes power grid voltage distortion to be converted into grid-side current harmonics. Comprising the following steps: decoupling a virtual admittance vector in a polar coordinate system, and optimizing under different load working conditions to obtain an optimal virtual admittance set; the system delay influence is compensated to ensure the robustness of the proposed method under different operation conditions; and a load power adaptive virtual admittance mechanism is constructed based on a segmented cubic Hermite interpolation method, so that suppression of network-side specific current harmonics in a wide load range is realized. The self-adaptive suppression method is used for self-adaptive suppression of the grid-side current harmonics of the GaN totem-pole bridgeless PFC converter.

The invention relates to the technical field of cable line power distribution network harmonic resonance treatment, in particular to a global and local cooperative partition cooperative resonance suppression method and device. The method comprises the steps of determining a harmonic conductance sensitivity index of each node in a power distribution network according to a target power distribution network admittance matrix parameter, and performing node region division; performing modal analysis on the admittance matrix parameters to obtain modal impedance and participation factors; determining a global optimal virtual admittance instruction value according to the modal impedance, the participation factor and the voltage distortion rate; according to the global optimal virtual admittance instruction value and the voltage distortion rate, determining a regional optimal virtual admittance instruction value in the region; and determining a harmonic compensation current value according to the regional optimal virtual admittance instruction value and the harmonic voltage. According to the method, harmonic suppression is realized for the whole power distribution network by adopting a partition and cooperation mode, and meanwhile, for background harmonic injection change, external interference such as resonance center offset and the like can be effectively overcome, so that the optimal harmonic suppression effect is realized.

The invention relates to the technical field of high-speed motor intelligent control, and discloses a high-speed motor intelligent control method and device for a cooling fan, and the method comprises the steps: carrying out the parameter collection of a high-speed fan motor, and obtaining a motor basic parameter group; performing motor overmodulation boundary calculation to obtain a linear PWM region threshold value and an overmodulation region threshold value; performing multi-objective optimization operation on the voltage distortion degree, the current harmonic quantity and the system loss to obtain an initial control parameter group; performing current harmonic analysis to obtain a current harmonic compensation value and a system delay compensation value; performing online state evaluation operation to obtain a PWM control parameter correction value, a current controller parameter correction value and a voltage vector distribution correction value; and performing fault feature analysis on the running state of the high-speed fan motor, and outputting a fault phase isolation instruction and a fault-tolerant control instruction, thereby improving the overall running effect of the high-speed fan motor.

A global optimization method for the quality of electric energy of a micro-grid. The method comprises: on the basis of an equivalent virtual impedance of an inverter of each node in a micro-grid and a local load of each node, establishing a node admittance matrix for the micro-grid (S1); on the basis of a weight value assigned to each node in the micro-grid and a voltage distortion rate of each node, constructing an objective function for the micro-grid (S2); on the basis of the node admittance matrix and the remaining capacity of the inverter of each node, constructing a constraint condition for harmonic modulation of each node in the micro-grid (S3); and in response to the constraint conditions being met, analyzing an optimal solution to the objective function, and on the basis of the optimal solution, adjusting the equivalent virtual impedance on each node (S4).

The invention provides a capacitance compensation method and device for a withstand voltage and partial discharge test of an extra-high voltage shunt reactor, and belongs to the field of reactor capacitance compensation, and the method comprises the steps: obtaining a winding inherent capacitance parameter, separating a high-frequency component from a low-frequency component, analyzing a space coupling path, and calculating a temperature and humidity induced variable capacitive reactance offset. A collaborative capacitance parameter matrix is generated after weighted fusion, a nonlinear polarization attenuation factor is introduced and dynamically calibrated, a capacitance compensation reference model is established, and compensation is executed through a multi-stage compensation device. According to the invention, through dynamic modeling, accurate capacitance compensation, voltage distortion suppression and improvement of partial discharge detection sensitivity, the problems of insufficient compensation precision and poor adaptability in the prior art are solved.

A wideband transmission circuit is provided. The wideband transmission circuit includes a power amplifier circuit(s) and an envelope tracking (ET) integrated circuit (ETIC). The ETIC is configured to generate a modulated voltage based on a modulated target voltage. The power amplifier circuit(s) amplifies a radio frequency (RF) signal(s) based on the modulated voltage and provides the amplified RF signal(s) to a coupled RF front-end circuit. In embodiments disclosed herein, the ETIC is configured to cause the modulated target voltage to be equalized by a real equalization filter to thereby compensate for a complex voltage distortion filter resulting from a coupling between the power amplifier circuit(s) and the RF front-end circuit. As a result, it is possible to reduce undesired instantaneous excessive compression and / or spectrum regrowth resulting from the complex voltage distortion filter to thereby improve efficiency and linearity of the power amplifier circuit(s).

The invention relates to a harmonic traceability method based on an electric energy quality index monitoring cloud platform, which is realized based on the electric energy quality monitoring cloud platform of an electric power system, and comprises the following steps: S1, selecting an attention node; s2, selecting a harmonic traceability time period; s3, selecting a correlation coefficient calculation item; s4, collecting and processing harmonic data of all feeders of each concerned node, and drawing a voltage distortion rate and harmonic current trend curve contrastive analysis chart of each feeder; and S5, the electric energy quality monitoring cloud platform uses a built-in traceability algorithm to calculate correlation coefficients, screens feeder lines whose correlation coefficients are greater than K, and outputs a harmonic traceability report. According to the invention, one-key positioning and accurate identification are carried out on the system harmonic source based on the electric energy quality monitoring cloud platform by adopting synchronous electric energy quality data of multiple monitoring points according to an advanced correlation traceability algorithm, so that the harmonic traceability accuracy and working efficiency are greatly improved, and the harmonic traceability cost is reduced.

The invention relates to the technical field of smart power grids, and provides a low-voltage power distribution network transparent fusion perception visual scene construction method and system, and the method comprises the steps: synchronously collecting voltage, current and equipment state data through power line carrier communication, a smart electric meter and a power distribution terminal, and building an annular queue with aligned time marks; a tree topology structure is constructed based on three-phase attributes, a connection matrix is generated, users are divided into visualization hierarchies with different transparencies through electrical distance calculation, and gradient coloring and special effect warning of an overload line are achieved in combination with current saturation mapping. The physical position and the electrical parameters are fused through polar coordinate system conversion, and a dynamic particle flow is generated to visually display current distribution; when the voltage sags, a voltage distortion propagation path is analyzed through waveform similarity backtracking, a disturbance source is positioned, and a pulse diffusion animation is triggered. Transparent fusion sensing of the running state of the low-voltage power distribution network, real-time early warning of line overload and second-level positioning of a disturbance source are achieved, and the intelligent operation and maintenance efficiency is improved.

The invention discloses a power grid parameter self-adaptive detection method suitable for a voltage distortion working condition of a wind power generation system. The method comprises the steps of 1, initializing a voltage estimation value according to priori knowledge of power grid voltage; step 2, sampling through a sensor to obtain a power grid voltage containing harmonic waves and direct current components; 3, calculating an estimation error according to the power grid voltage sampling value; 4, designing a self-adaptive observer, and estimating an intermediate variable; 5, updating the voltage estimation value according to the intermediate variable obtained in the step 4; step 6, estimating the power grid voltage of the harmonic component and the direct current component of the voltage by using the intermediate variable obtained in the step 4; and step 7, repeating the step 2 to the step 6, continuously updating the parameter estimation value, and obtaining the real-time parameter of the power grid voltage. According to the invention, when the voltage of the power grid is distorted, the voltage parameter can still be accurately detected, the harmonic and direct current components are separated and extracted under the condition of no steady-state error, and the safe and stable operation of a power system is ensured.

The invention discloses an optimized virtual vector modulation strategy of a T-type three-level inverter, which is characterized in that a sector is re-divided based on the virtual vector modulation strategy, a synthesis mode of a virtual vector is optimized, a low-amplitude common-mode voltage vector is adopted to synthesize the virtual vector, on one hand, common-mode voltage generated by the inverter can be inhibited, and on the other hand, the common-mode voltage generated by the inverter can be inhibited; and on the other hand, the optimized modulation method does not influence the neutral point potential, the smoothness of the direct output voltage of the inverter is improved, the voltage quality is improved, and the method has the advantages of low harmonic content of the output current and the like. In addition, the method solves the problems of inverter output voltage distortion, common-mode voltage spike and the like caused by a dead zone effect through a voltage vector compensation method, and has guiding significance for improving the reliability of a photovoltaic system and a micro-grid system.

The invention relates to an electric pollution treatment method, system and terminal based on an ultra-wide spectrum absorber, and relates to the technical field of electric pollution treatment, and the method comprises the steps: obtaining a voltage signal and an equipment position point of equipment needing to be protected; calling an equipment model based on the equipment position point; analyzing and determining a voltage distortion rate according to the voltage signal and the equipment model; according to the voltage distortion rate and equipment model analysis, determining and selecting an initial specification; specification adjustment information is analyzed and determined according to the equipment position points; based on the specification adjustment information, the selected initial specification is adjusted to form a selected final specification, and the ultra-wide spectrum absorber corresponding to the selected final specification is installed to the equipment needing protection for electric pollution treatment. The method has the effect of improving the equipment protection capability.

The invention belongs to the technical field of power generation and power supply, and particularly relates to a power distribution network electric energy quality monitoring and comprehensive evaluation method and system, and the method comprises the steps: obtaining an environment reference parameter, three-phase voltage data, three-phase current data, transformer harmonic current and transformer harmonic current times; calculating a transformer voltage distortion rate and a transformer total current which represent the overall level of the electric energy quality; calculating a harmonic erosion index representing the load side harmonic frequency spectrum complexity; calculating a thermal harmonic coupling degree used for judging a high temperature generation reason; calculating a power grid health score; grading the operation state of the power grid; judging the fault type; and issuing adjustment instructions to different fault types. The technical problem that the dynamic coupling relation between the harmonic form and the equipment thermal state cannot be evaluated in the prior art is effectively solved.

The invention relates to the technical field of power distribution network harmonic treatment, in particular to a power distribution network harmonic source positioning method and device, electronic equipment and a storage medium, and the method comprises the steps: firstly obtaining a first voltage waveform data queue and a second voltage waveform data queue corresponding to two adjacent time nodes; then waveform distortion analysis is carried out on the first voltage waveform data queue and the second voltage waveform data queue respectively, and a first voltage distortion rate and a second voltage distortion rate are obtained; according to the first voltage distortion rate and the second voltage distortion rate, whether a harmonic source is connected to the power distribution network or not is determined; and finally, when a harmonic source is accessed, extracting a plurality of node current pairs, and determining an area where the harmonic source is located according to the plurality of node current pairs. According to the embodiment of the invention, harmonic source positioning can be completed by using less monitoring equipment for harmonic source positioning, and equipment resources are saved.

The invention discloses a power distribution network harmonic suppression method based on virtual admittance of a photovoltaic grid-connected inverter, and the method comprises the following steps: generating a harmonic compensation current through the photovoltaic grid-connected inverter, constructing a virtual admittance control mechanism based on the harmonic compensation current, and obtaining a mapping relation between a virtual admittance value and a phase angle on the harmonic suppression effect; modeling a photovoltaic grid-connected inverter of the power distribution network, and constructing a virtual admittance regulation mechanism of the power distribution network; and based on a virtual admittance control mechanism, taking each virtual admittance parameter as an optimization variable, and carrying out a multi-photovoltaic grid-connected inverter collaborative optimization strategy to realize graded treatment of power distribution network harmonics. According to the method, a virtual admittance control mechanism is constructed, and a photovoltaic grid-connected inverter is equivalent to earth admittance; and harmonic fractional compensation and global optimization configuration are realized by combining sensitivity analysis of voltage distortion of each node. The problem that the VDAPF only adjusts through harmonic conductance and neglects the impedance characteristic of the power distribution network and the uncertainty of the harmonic phase is solved, and the harmonic compensation capability is remarkably improved.

This application provides a DC boost grid connection method, system, device, equipment, medium, and product, relating to the field of new energy grid connection. The method employs a cascaded topology of H-bridge modules to dynamically adjust the DC voltage output of the photovoltaic array according to the light intensity to match the light conditions. Simultaneously, it dynamically adjusts the number and switching times of the H-bridge modules based on the grid voltage demand, ensuring that the peak value of the multi-level AC voltage output by the adjusted H-bridge module group matches the voltage demand. Furthermore, it actively constrains the harmonic distortion rate and amplitude fluctuation rate of the output voltage to be below preset thresholds. Without requiring a power frequency boost transformer and a large-capacity inverter, it achieves direct boost grid connection from photovoltaic DC to high-voltage AC. It also solves the voltage distortion and amplitude fluctuation problems that easily occur during the dynamic adjustment of the number of modules, improving grid-connected power quality and system operational stability, and reducing the cost of the photovoltaic DC boost grid connection system.

The present disclosure relates to a method and device for monitoring the energy-saving operation of power quality based on multi-source data of AI Internet of Things. The method includes: acquiring the transient electromagnetic signal of a permanent magnet operated circuit breaker and extracting the timing characteristic parameters of the transient electromagnetic signal; determining whether there is a harmonic problem caused by an inverter and whether there is a voltage sudden rise or sudden drop, and determining whether the timing characteristic parameters are related to power quality disturbances; obtaining the voltage mutation amplitude and the voltage sudden rise rate to obtain the voltage fluctuation degree, and outputting the discharge strategy of the energy storage system through a pre-established discharge optimization model; respectively calculating the voltage distortion rate and the three-phase voltage unbalance degree, and selecting the charging strategy of the energy storage system through a pre-established charging optimization model; predicting the sudden rise rate and sudden drop rate of the sample, obtaining a prediction result, and forming an energy-saving optimization scheme for the energy storage charge and discharge strategy according to the prediction result; The present invention automatically adjusts the charge and discharge power of the energy storage battery to form an energy-saving optimization scheme, effectively improving the stability of the power grid.

To provide a highly-precise voltage reference circuit.SOLUTION: A circuit (70) includes a voltage reference circuit (72) that includes an output terminal (74). The voltage reference circuit (72) is configured to generate an output voltage having a first transfer function of a voltage with respect to strain at the output terminal (74). The circuit (70) also includes a strain compensation circuit (78) having an input terminal connected to the output terminal (74) of the voltage reference circuit, and a strain compensation circuit output terminal (80). The strain compensation circuit (78) is configured to receive the output voltage including the first transfer function at the input terminal. The strain compensation circuit (78) has a second transfer function of a voltage with respect to strain that is substantially opposite to that of the first transfer function, thereby outputting a compensated voltage that is substantially independent from strain at the strain compensation circuit output terminal (80).SELECTED DRAWING: Figure 5

The invention discloses a dead-zone predictive current control method for a dual three-phase permanent magnet synchronous motor, which is based on a dual three-phase permanent magnet synchronous motor driving system and comprises the following steps of: 1, providing a method for compensating the nonlinearity of an inverter on line, and compensating the nonlinearity of the inverter through current injection; and step 2, designing a DPHCC method based on an extended state observer (ESO) so as to eliminate the interference of parameter mismatching and unmodeling. According to the method, the voltage distortion error can be determined without machine parameter priori knowledge, the DPHCC scheme is realized in the harmonic subspace to suppress the harmonic current, and the interference of non-modeling on the harmonic plane is estimated and compensated by designing the ESO, so that the robustness of the system is enhanced.

The present application belongs to the field of power electronics technology, and specifically discloses a voltage compensation method and device for a cascaded multi-level inverter. In the present application, the predicted value of the output current of each H-bridge inverter module in the cascaded multi-level inverter is used to compensate the turn-on angle and turn-off angle of each H-bridge inverter module respectively, and the phase shift control signal of each switching device in the H-bridge inverter module is distributed according to the compensated turn-on angle and turn-off angle, thereby effectively compensating for the PWM voltage distortion caused by the dead zone effect and the switch parasitic capacitance effect. In addition, the present application does not need to detect the output current of the H-bridge inverter module, eliminating the current detection hardware and optical fiber communication delay time. In the high-frequency cascade topology, the low-order harmonics introduced by the dead zone effect and the switch parasitic capacitance effect can be effectively suppressed, significantly improving the waveform quality.

This invention discloses a predictive maintenance system for medical X-ray equipment, belonging to the field of medical equipment maintenance technology. It includes a multi-source data acquisition module, a feature construction module, a coupled degradation modeling module, a risk assessment module, and a maintenance strategy generation module. Based on voltage distortion rate, current harmonic components, and temperature field gradient, this invention extracts the standard deviation of voltage distortion rate, the total distortion coefficient of current harmonics, and the rate of change of temperature gradient after denoising using wavelet thresholding, and fuses them into a feature vector. Combining a long short-term memory network and a Bayesian network, it calculates a comprehensive degradation index of multi-parameter coupling; subsequently, it constructs a multi-parameter feature space and outputs a comprehensive risk level through unsupervised learning methods; finally, it generates targeted maintenance strategies based on the risk level and optimization algorithms. This invention achieves accurate prediction and intelligent maintenance of medical X-ray equipment faults, reduces sudden failures, lowers maintenance costs, and improves equipment operational reliability and diagnostic and treatment safety.

The invention discloses a medical X-ray equipment fault predictive maintenance system, and relates to the technical field of medical equipment maintenance. Comprising a multi-source data acquisition module, a feature construction module, a coupling degradation modeling module, a risk judgment module and a maintenance strategy generation module. The method comprises the following steps: based on a voltage distortion rate, a current harmonic component and a temperature field gradient, extracting a voltage distortion rate standard deviation, a current harmonic total distortion coefficient and a temperature gradient change rate after de-noising through a wavelet threshold method, and fusing into a feature vector; calculating a multi-parameter coupled comprehensive degradation index in combination with a long short-term memory network and a Bayesian network; then constructing a multi-parameter feature space, and outputting a comprehensive risk level through an unsupervised learning method; and finally, a targeted maintenance strategy is generated based on the risk level and an optimization algorithm. According to the invention, accurate prediction and intelligent maintenance of faults of the medical X-ray equipment are realized, sudden faults are reduced, the maintenance cost is reduced, and the operation reliability and diagnosis and treatment safety of the equipment are improved.

This invention belongs to the field of power generation and supply technology, specifically relating to a method and system for monitoring and comprehensively evaluating the power quality of distribution networks. The method includes: obtaining environmental reference parameters, three-phase voltage data, three-phase current data, transformer harmonic current, and transformer harmonic current order; calculating the transformer voltage distortion rate and total transformer current, which characterize the overall power quality level; calculating the harmonic erosion index, which characterizes the complexity of the harmonic spectrum on the load side; calculating the thermal harmonic coupling degree used to determine the cause of high temperatures; calculating the grid health score; classifying the grid operating status into levels; determining the fault type; and issuing adjustment commands for different fault types. This invention effectively solves the technical problem that existing technologies cannot assess the dynamic coupling relationship between harmonic morphology and equipment thermal state.

The invention relates to the technical field of three-phase systems, and provides a three-phase voltage state estimation method and system based on virtual coordinates, and the method comprises the steps: calculating the voltage peak value of each phase for three-phase voltages, and determining that a phase is open if the peak voltage of a certain phase is lower than a threshold value in the three peak voltages; for three-phase voltage, virtual beta-axis voltage is generated through an all-pass filter, actual beta-axis voltage is obtained through Clark transformation, the product of the virtual beta-axis voltage and the actual beta-axis voltage serves as an evaluation function, and a positive sequence and a negative sequence are distinguished according to the positive and negative of the evaluation function. The system state can be accurately and effectively judged under the conditions of three-phase imbalance and voltage distortion, the anti-noise capability and the anti-harmonic interference capability are high, and safe and stable operation of equipment under the abnormal condition is ensured.

The invention relates to the technical field of anomaly detection, in particular to a substation equipment anomaly detection method based on deep learning. Comprising the following steps: determining whether the operation of a single secondary device is qualified based on a voltage distortion rate, marking the unqualified secondary device as an abnormal device, and determining whether the operation of the secondary device is qualified based on a frequency deviation for the secondary device whose voltage distortion rate is greater than a second preset voltage distortion rate and less than or equal to a first preset voltage distortion rate, unqualified secondary equipment is marked as abnormal equipment, and the secondary equipment is a relay protection device; based on the disqualification ratio, determining that the reason for disqualification of the test process is preset matching degree abnormity or secondary equipment detection abnormity; adjustment is correspondingly carried out according to reasons for disqualification of the test process; according to the invention, the equipment abnormity detection efficiency is effectively improved.

1. The name of the design product: active filter. 2. The use of the design product: for inhibiting AC voltage distortion and current harmonics. 3. The design points of the design product: in shape. 4. The picture or photo that best shows the design points: design 1 perspective view 1. 5. Design 1 is designated as the basic design.

The invention is suitable for the technical field of electric energy metering, and relates to an electric energy metering method and device of an electric energy meter. Corresponding fundamental wave voltage current components, harmonic wave voltage current components, corresponding fundamental wave phase angles and harmonic wave phase angles are extracted, and based on the data, fundamental wave positive sequence active power, reactive power, non-fundamental wave equivalent apparent power, voltage distortion power, current distortion power, harmonic wave apparent power, unbalanced apparent power and the like are obtained through calculation; various electric parameters of the electric energy meter are metered so as to guide an electric power department to charge, make economic decisions, measure main harmonic pollution sources and the like, and the quality of electric power service is greatly improved.

The utility model discloses a kind of electric energy quality DNV voltage distortion rate elimination stabilizer and sampling circuit, including load equipment and for the DVA voltage stabilizer on the load equipment, still including with the DVA voltage stabilizer and the load equipment electric connection A circuit, B circuit, C circuit and N circuit.The beneficial effect of the utility model is: through filter current transformer, voltage stabilizer current transformer and DVA voltage stabilizer, realize the process in the use of load equipment, inhibit load equipment dynamic and steady-state voltage drop and voltage variable, eliminate surge, eliminate voltage flicker, with good dynamic voltage stability capacity, output voltage reaches precision ±1% -5% adjustable, can effectively filter each harmonic, three-phase unbalance, improve power factor, improve power supply electric energy quality, and harmonic elimination stabilizer has ideal energy-saving effect, between 1-8% in different field energy-saving effect.