66results about How to "High inverter efficiency" patented technology

The utility model discloses a variable-frequency power supply of high power transistor, mainly comprising a three-phase bridge rectifier circuit, a plane-wave filter circuit, a combined contravariant bridge circuit and a control protection circuit. The utility model is characterized in that the three-phase power-frequency alternating current is converted into the direct current by connecting with an output power via a load circuit, and then the direct current is contradictorily converted into a single-phase high frequency alternating current. With high power electrical and electronic element, the utility model has the advantages of wide frequency application range, high power output and high power frequency, meeting the process requirement of the modern heat treatment. The power frequency of the utility model covers the intermediate frequency band and the superaudio frequency band, no special starting circuit is required and the inversion efficiency is high, therefore the application prospect is wide.

A vehicle including a secondary battery includes an electricity generation device; an amount-of-stored electricity detection portion; an inverter that converts electric power output from the secondary battery into alternating-current power; an external load connection portion that connects an external load to the secondary battery via the inverter; and a control portion (10) that controls charging / discharging of the secondary battery. The control portion causes the electricity generation device to charge the secondary battery based on a value detected by the amount-of-stored electricity detection portion such that the amount of electricity stored in the secondary battery is in a predetermined range, and the control portion performs a control such that when the electric power is supplied to the external load during stoppage of the vehicle, an upper limit value of the amount of stored electricity is different from the upper limit value during traveling of the vehicle.

In an electric compressor, an inverter case of an inverter is externally attached to an end wall of a housing in an axial direction on the side of a suction port to a compression mechanism. An intake passage for leading fluid returned from the outside into the suction port is provided in the inverter case. The intake passage has a thermal binding portion for thermally binding the intake passage to the inverter. According to the above structure, an exclusive part in the housing is eliminated even though the inverter is installed in the electric compressor, and the inverter is cooled efficiently.

The invention discloses a grid-connected circuit for a small-sized wind-driven generator. According to the grid-connected circuit for the small-sized wind-driven generator, an alternating current input side is connected with a three-phase output of the wind-driven generator through a three-phase single-switch BOOST rectification circuit, and the three-phase output of the wind-driven generator is connected with a three-phase capacitor; a rectification output side is directly connected with the three-phase single-switch BOOST rectification circuit, and the rectification circuit simultaneously has the functions of active power factor correction and maximum power tracking control; an inversion side is connected with a power grid by adopting a voltage type single-phase interleaved parallel inversion circuit; signal sampling circuits are divided into a voltage signal acquisition circuit and a current signal acquisition circuit, and the voltage signal acquisition circuit respectively acquires direct current voltage output by a rectification side, direct current voltage input by the inversion side and alternating current voltage of the power grid in real time; the current signal acquisition circuit respectively acquires direct current output by the rectification side and current output to the power grid by the inversion side in real time, namely grid-connected current signals; and a control circuit respectively controls switching tubes in the three-phase single-switch BOOST rectification circuit and the voltage type single-phase interleaved parallel inversion circuit.

The invention relates to a method for dynamically adjusting busbar voltage to improve grid connection efficiency. The working range of grid voltage from lowest limit to highest limit is divided into at least two levels and each level corresponds to a set busbar voltage directive value; and a control system detects the effective value of the grid voltage in real time, and when the grid voltage is within one level, if the busbar voltage directive value at the moment is not equal to the set busbar voltage directive value corresponding to the level, the busbar voltage directive value is adjusted to the set value. Since the amplitude of the busbar voltage is dynamically adjusted according to the grid voltage value detected in real time, the invention has the advantages that the overall efficiency and the reliability of the grid-connected inverter are improved, the device stress is reduced and the service life of the capacitor is prolonged.

The invention discloses an improved main circuit structure of a photovoltaic synchronization inverter. The improved main circuit structure comprises a photovoltaic (PV) battery board, a capacitor Cin, distributed capacitors C1 and C2, a non-isolation direct-current / direct-current (DC / DC) converter, a capacitor C, an H bridge consisting of power switching devices V1, V2, V3 and V4, and diodes D1, D2, D3 and D4 which correspond to one another one to one, an afterflow loop on the voltage positive half circle of a power grid consisting of a power switching device V5 and diodes D5 and D7, an afterflow loop on the voltage negative half circle of the power grid consisting of a power switching device V6 and diodes D6 and D8, a filter circuit consisting of inductors Lf1 and Lf2 and a capacitor Cf,and a common mode resistant voltage filter H-bridge capacitor group consisting of capacitors C3, C4, C5 and C6. A synchronization inversion circuit for executing the improved main circuit structure has the advantages of capability of effectively restraining common mode voltage / current, high inversion efficiency, small volume, light weight, low electromagnetic noise and the like.

The invention discloses a method for improving grid-connected performance by variable switching frequency. The method comprises the following steps of calculating the output power value of a grid-connected inverter by detecting the voltage value of a grid and the grid-connected current value of the grid-connected inverter in real time; and dynamically adjusting the switching frequency value of a power switching tube of the grid-connected inverter according to the output power value of the grid-connected inverter. With the adoption of the method for adjusting the switching frequency of the power switching tube, the problem that the grid-connected current harmonics are bad in case that the output power of the grid-connected inverter is smaller is solved and the pollution to the grid is reduced. Meanwhile the method has the advantages of improving the inversion frequency in case that the output power of the grid-connected inverter is larger, reducing the size of an LC filter, decreasing the cost, improving the temperature rise, and enhancing the system reliability.

A drive for motor that can be operated up to a high load while improving efficiency of an inverter is provided. The drive for a motor includes: a voltage conversion circuit 2 that changes a value of a DC voltage and outputs the DC voltage; an inverter 3 that converts the DC voltage output from the voltage conversion circuit into an AC voltage, the conversion being performed by a switching operation of a switching element; and control means that controls the DC voltage output from the voltage conversion circuit and controls a voltage output from the inverter by the switching element so as to drive the motor 1. The control means executes DC voltage adjustment control in which the DC voltage output from the voltage conversion circuit is controlled based on a modulation factor of the DC voltage modulated by the inverter so that the modulation factor becomes closer to 1.

The invention relates to a DC (direct current) / AC (alternating current) inverter circuit, comprising a buck chopper and a commutation rectification circuit, wherein the buck chopper comprises a power switching tube, a diode, an inductor and a capacitor modulated by an SPWM (sinusoidal pulse width modulation). An SPWM mode is adopted to regulate the duty ratio of a high-frequency switching tube in the buck chopper so as to convert DC energy into sine half-waves; and the commutation rectification circuit formed by four controlled rectifiers carries out commutation rectification on the sine half-waves so as to finish the invertion from DC to sine AC. Compared with a common full-bridge inverter circuit, in the novel DC / AC inverter circuit, the structure is simple, the fewer high-frequency tubes are used, the invertion efficiency is improved and the cost is reduced. In the commutation process, the inverted AC is output to generate constant common-mode voltages so as to suppress common-mode currents; and the switching tube in the buck chopper can separate low-frequency input from high-frequency output when the switching tube is switched off, thus reducing the EMI (electro magnetic interference).

The invention provides a high-frequency isolation-type five-level inverter. The high-frequency isolation-type five-level inverter consists of an input direct-current power supply unit, voltage-dividing capacitors, a high-frequency isolation-type five-level conversion unit, a high-frequency isolation transformer, a cyclic wave converter, an output filter and an output alternating-current load, wherein on the basis of a full-bridge inverter, four capacitors are connected to two ends of an input direct-current voltage source in parallel to divide the voltage, so that five levels of Ui / 2, Ui / 4, 0, minus Ui / 4, minus Ui / 2 can be generated on the front end of the transformer, the five levels also can be sensed by a transformer side edge, the voltage stress on a switch tube can be reduced, and the waveform quality of the output voltage can be improved. The inverter has two levels of power transformation (direct current (DC)-high frequency alternating current (HFAC)-low frequency alternating current (LFAC)) and has the advantages of bi-directional power flow, low voltage stress on a switch device, good voltage spectrum characteristics on the front end of the output filter, small size of the output filter, low voltage stress on the switch tube and capability for electrically isolating the alternating-current load and the direct-current power supply in a high-frequency manner. The inverter can be applied to the application field with higher voltage and large power.

A small signal model based on a single-phase cascaded island ACHB inverter system and a stability analysis method based on a floquet theory are provided. The single-phase cascaded island ACHB invertersystem includes a digital controller with double closed loop control, an LC filter, a load and three single-phase H-bridge inverters operating at low voltage, medium voltage and high voltage respectively. The digital controller is connected to a filter capacitor. The small signal model based on the single-phase cascaded island ACHB inverter system, in consideration of a linear resistive load withsmall signal disturbance, separates a disturbance component, obtains a modulation signal expression by coordinate transformation, and analyzes the system stability by using the floquet theory. The beneficial effect is that a multi-level inverter reduces the harmonic components in the output voltage due to the increase of the output level of a main circuit, and the stability analysis of the smallsignal model solves the difficulty of modeling the nonlinear circuit of a converter, the dynamic characteristics of steady-state operating point of the converter are described by unified differentialequations, the stability domain of the system is accurately verified by the floquet theory, and a reliable criterion is provided for the stable operation of the whole single-phase cascaded island inverter system.

The invention discloses a high-power modular battery formation charging / discharging system, belonging to the field of battery formation charge / discharge. The system comprises an invertible DC (direct current) power module, a DC bus, a conversion charging / discharging module and a central control unit. The invertible DC power module adopts an automatic master-slave current sharing technology, can automatically configure the module number according to the system capacity, realizes automatic current sharing among the modules, and can inversion-feed the redundant electric energy back to the power grid so as to realize master-slave redundant invertible DC power module design; the DC bus transmits electric energy in the system; the conversion charging / discharging module is directly connected with the DC bus; by adopting the automatic master-slave current sharing technology, each module can form a loop independently for production, or multiple modules are freely connected in parallel to form a loop for production; and the central control unit is connected with the invertible DC power module and the conversion charging / discharging module through the bus, and can realize the functions of operation data acquisition, system resource allocation, module alternation coordination, system capacity reduction protection and the like.

The invention relates to a DC / AC grid connected inverter circuit and a power factor adjusting method. The DC / AC grid connected inverter circuit comprises an enhanced voltage reduction chopper circuit and a controlled silicon power frequency phase inverter circuit, wherein the enhanced voltage reduction chopper circuit comprises an SPWM (Sinusoidal Pulse Width Modulation) modulated power switch tube, a double freewheel diode, a power factor adjusting power switch tube, an inductor and a capacitor. Direct current is converted into a half sine wave by adjusting the duty ratio of the high frequency switch tube in the enhanced voltage reduction chopper circuit; and power factor adjustment can be realized by adjusting the conduction mode of the power factor adjusting power switch tube. The direct current half sine wave is subjected to phase inversion by the phase inverter circuit composed of four low frequency controlled silicon to obtain a full sine wave so as to finish inversion from direct current to sine alternating current. Compared with the traditional full bridge grid connected inverter circuit, the grid connected inverter circuit provided by the invention is simple in structure, strong in overcurrent resistance, high in stability, high in inversion efficiency and low in cost, and the number of high frequency tubes is reduced by half. In the switching and phase inverting process, a constant common mode voltage is produced from the alternating current output of the inverter, so that the common mode current is inhibited and the EMI (Electro-Magnetic Interference) interference is reduced.

A high-voltage and high-power uniterrupted power source has its circuit consisting of a three-phase AC input transformer and a power unit module circuit which is composed of 6 power unit modules and each of them consisting of rectifier, DC filter capacitor, IGBT single phase full bridge inverter, storage battery set and electric charger, each phase having 2 power unit modules connected in seriesand connected in front or rear with reactor and three-phase output transformer or is composed of 12, 15 or 21 power unit modules, each correspondingly having 4,5 or 7 power unit modules connected in series and connected with three-phase output transformer and controller separately for the individual charger being used by each independently. The controller is composed of a chip circuit connected to each other, industrial computer and logic program controller.

The invention relates to the technical field of inverters, and discloses a two-pole single-phase photovoltaic inverter and an inversion method thereof. The inverter comprises a forestage BOOST voltage booster circuit of which the output end is connected in parallel with an intermediate stage capacitor, wherein a backstage inversion circuit comprises a first circuit and a second circuit which are connected in parallel with the intermediate stage capacitor; the first circuit comprises second, fourth and sixth switches which are connected in series in sequence; the second circuit comprises third, fifth and seventh switches which are connected in series in sequence; a second diode is connected in series between nodes of the second and fourth switches and nodes of the fifth and seventh switches; a third diode is connected in series between nodes of the fourth and sixth switches and nodes of the third and fifth switches; a second inductor is connected in series between nodes of the second and fourth switches and the output end of the backstage inversion circuit; a third inductor is connected in series between nodes of the third and fifth switches and the output end of the backstage inversion circuit; and the output end of the backstage inversion circuit is connected in parallel with a power grid. Due to the adoption of the scheme, leakage current can be reduced effectively, the inversion efficiency is optimized, and adaptation to large-range change of an input voltage is realized.

The invention discloses a transformer-free type single-phase photovoltaic inverter with mixed voltage clamping. The transformer-free type single-phase photovoltaic inverter comprises an energy storagevoltage dividing unit, a power inversion unit, a mixed clamping unit and a filter unit. When the inverter works, with the help of six diodes, five power switches with antiparallel diodes are cooperated to enable an alternating current side to be continuous and clamp common-mode voltage of the same to be half of direct current input voltage when the inverter outputs zero level, and thereby complete elimination of the common-mode voltage is achieved, and required bus voltage is only half of a half-bridge type circuit. Meanwhile, the transformer-free type single-phase photovoltaic inverter adopts a unipolar pulse width modulation mode, so that output current is small in ripple, volume and weight of a filter are reduced, and loss of a magnetic element is reduced at the same time; the switch operates less frequently in a switching period, so that switching loss is reduced; and therefore, the inverter provided by the invention is high in output efficiency that inversion efficiency up to 98%can be obtained.

The sinusoidal inverter circuit includes DC / DC converter circuit, dynamic pre-loading circuit, inverting bridge circuit, DC power source to provide input DC voltage to the DC / DC converter circuit, monochip computer circuit to generate high-precision semi-sinusoidal reference signal for the high-frequency switching control of the DC / DC converter circuit. The output of the DC / DC converter circuit is connected to the dynamic load circuit and the inverting bridge circuit, and the output of the inverting bridge circuit of connected to the AC load via a filter circuit. There is only one high frequency conversion in the whole conversion, and this results in low switch loss and high conversion efficiency.

The disclosed high-efficient saving-energy inversion circuit comprises: a power tube, a recovery multi-diode, and an output filter circuit to form together into a single phase four-tube semi-bridge inversion circuit, or three-phase four-tube semi-bridge inversion circuit. Wherein, it sets drive voltage in a period not always carrier frequency, while half-period wave is constant past or broken. Compared with prior art, thereby, this invention reduces switch frequency so as the switch tube loss as half of original, then increases inversion efficiency, and adds power density.

The invention relates to the field of solar power generation, in particular to a high-power solar three-phase grid-connected inverter. The technical scheme for implementation of the inverter includes that the high-power solar three-phase grid-connected inverter comprises a case, an electrical cabinet, an operation transformer, an anode copper bar, a cathode copper bar, a first contactor, a first current sensor, an inversion module, an electric reactor, a three-phase capacitor, a second current sensor, a filter, a second contactor and a circuit breaker. The inversion module comprises at least one power module group, each power module group comprises three power modules, and each power module is used for realizing current conversion of one phase and provided with an independent laminated busbar. The high-power solar three-phase grid-connected inverter requires low power of a radiation fan and has better radiation effects.

The invention provides an alternating current optimizer system, which comprises a photovoltaic assembly, an alternating current optimizer and a grid-connection control cabinet, wherein the alternatingcurrent optimizer comprises a voltage booster circuit and inversion circuits; the grid-connection control cabinet transmits electric network information to the alternating current optimizer; the alternating current optimizer is switched between a first mode and a second mode on the basis of the electric network information and the electric energy information of the alternating current optimizer.In the first mode, the voltage booster circuit is controlled to realize a direct connection state; the inversion circuits are controlled to perform MPPT tracking and inversion function on the photovoltaic assembly; at the moment, the voltage booster circuit is in the direct connection state, a plurality of inversion circuits are in cascade connection; the primary topology is realized; the system inversion efficiency can be improved. In the second mode, the voltage booster circuit is controlled to perform MPPT tracking on the photovoltaic assembly; the inversion circuits are controlled to perform inversion on the photovoltaic assembly; the regulation is performed on the photovoltaic assembly through the voltage booster circuits, so that the system can realize the normal operation; the use rate of the system is improved.

The invention discloses a three-phase inverter drive method and device employing SPWM control. The method comprises the following steps: obtaining the current intensity and direction of a current which flows outside from the intersection of an emitter of an upper bridge arm component and a collector of a lower bridge arm component; determining a target drive module to be located in a working state from a first drive module and a second drive module according to the current intensity and direction; generating an enable signal of controlling the target drive module; and transmitting the enable signal to the target drive module, and changing an original all-time uninterrupted work mode into an intermittent work mode. The drive method and device greatly reduce power consumption of switch tubes and drive circuits and avoid the problem that the maximum withstand voltage spike of an IGBT grid is exceeded due to upper bridge and lower bridge-driven intercoupling and positive interference superposition of drive signals caused by electromagnetic radiation generated by the high current.

A switching power supply integrated UPS is characterized by that the power supply of electric appliance is integrated with UPS for sharing a single PWM and switching transformer by primary power supply and standby power supply and directly converting the voltage of battery to the voltage needed by electric appliance. Its advantages are small size, light weight, simple circuit and low cost.

The invention discloses an active clamping type high-frequency chain inverter which comprises a primary side conversion circuit, a high-frequency transformer, an active clamping circuit, a secondary side conversion circuit and a low-pass filter part. The primary side conversion circuit is a DC / AC inverter circuit; the active clamping circuit comprises an active clamping bridge and a clamping capacitor, losslessly absorbs leakage inductance energy of the high-frequency transformer and feeds back the leakage inductance energy to an input end; the secondary side conversion circuit is a hybrid AC conversion circuit and is composed of a DC / AC half-bridge and an AC / AC half-bridge, and the two half-bridges form a full bridge and output alternating current. According to the invention, single-stage high-frequency isolation inversion from input to output is realized, and no intermediate direct-current bus exists. Under the same working condition, the withstand voltage and output of the device are the same as those of a full-bridge inverter. And through lossless active clamping, the leakage inductance voltage spike problem of the high-frequency transformer is solved. The inverter has the characteristics of high isolation, small size, simplicity in control, good stability, high efficiency and the like.

The invention belongs to the technical field of wind power and solar energy grid-connected power generation, and particularly relates to a multifunctional centralization type wind-solar complementarypower generation system grid-connected controller. The controller comprises a power main circuit and a control circuit, wherein the power main circuit is characterized in that the input end and the output end of a maximum power tracking circuit are independently connected with a photovoltaic array and a change-over switch, the input end and the output end of a fan unloading circuit are independently connected with a fan output end and the change-over switch, the wiring terminal of the change-over switch is simultaneously independently connected with the charging and discharging control circuitand the direct-current load of a storage battery and the input end of the DC (Direct Current) / AC (Alternating Current) inverter circuit, the charging and discharging control circuit end of the change-over switch is connected with the storage battery, the output end of the DC / AC inverter circuit is connected with a power grid, and a main connection line between the DC / AC inverter circuit and the power grid is connected with an alternating current load. The control circuit adopts a dual-core processor, a controller core adopts the combination of a single chip microcomputer and a DSP (Digital Signal Processor), and a serial port communication way is adopted for connection. The controller has the advantages of high integration degree and good grid-connected effect and is suitable for a grid-connected wind-solar complementary power generation system.

The invention discloses a method for improving grid-connected performance by variable switching frequency. The method comprises the following steps of calculating the output power value of a grid-connected inverter by detecting the voltage value of a grid and the grid-connected current value of the grid-connected inverter in real time; and dynamically adjusting the switching frequency value of a power switching tube of the grid-connected inverter according to the output power value of the grid-connected inverter. With the adoption of the method for adjusting the switching frequency of the power switching tube, the problem that the grid-connected current harmonics are bad in case that the output power of the grid-connected inverter is smaller is solved and the pollution to the grid is reduced. Meanwhile the method has the advantages of improving the inversion frequency in case that the output power of the grid-connected inverter is larger, reducing the size of an LC filter, decreasing the cost, improving the temperature rise, and enhancing the system reliability.

The invention relates to an inversion device and method for converting direct-current voltage into alternating-current voltage and an inverter and relates to the field of electronics. The inversion device comprises a first inversion module, a first follow current module, a second inversion module and a second follow current module, the first inversion module is used for inverting a direct-currentpower source to acquire a positive half-wave signal of an alternating-current power source, the first follow current module is used for inverting the direct-current power source into a negative half-wave signal of the alternating-current power source, the second follow current module is used for isolating follow current from the direct-current power source after the second inversion module is disconnected. The inversion device can lower common-mode leakage current, loop oscillation, ripple wave current and voltage stress of a switch tube in the inversion device, reduce energy loss of the switch tube and damage of the voltage stress to the switch tube, prolong service life of the switch tube, lower radiation of the switch tube and heat value and energy loss of an inductor and improve inversion efficiency.

The invention discloses a collaborative robot driver based on EtherCAT, hardware FOC and a gallium nitride power transistor and a control method. The driver comprises an MCU microcontroller unit module, an EtherCAT slave station module, a hardware FOC module, a gallium nitride power inversion module, a sensor module, a system protection module, a motor band-type brake module, a power supply module and an external equipment module which are connected with one another. Wherein the MCU microcontroller unit module comprises a minimum peripheral circuit and is responsible for EtherCAT protocol stack processing and hardware FOC related register configuration. The hardware FOC module is responsible for hardware execution of a current loop, a speed loop and a position loop. According to the invention, a highly integrated hardware FOC algorithm and a gallium nitride (GaN) power transistor are adopted, and an EtherCAT bus is adopted to carry out data communication, so that the driver layout space is smaller, the energy consumption is lower, the real-time performance is better, the communication rate is higher, and the inversion efficiency and the precision stability are also higher.

The invention discloses a combined type inverter. The combined type inverter comprises input voltage, and a capacitor C1 connected between positive and negative electrodes of the input voltage in parallel, the positive electrode of the input voltage is connected with drain electrodes of an MOS tube Q1, an MOS tube Q3 and an MOS tube Q5 in parallel, a source electrode of the MOS tube Q1 is connected with a drain electrode of an MOS tube Q2, a source electrode of the MOS tube Q3 is connected with a drain electrode of an MOS tube Q4, a source electrode of the MOS tube Q5 is connected with a drain electrode of an MOS tube Q6, source electrodes of the MOS tube Q2, the MOS tube Q4 and the MOS tube Q6 are connected with the negative electrode of the input voltage; and a position between a source electrode of the MOS tube Q1 and the drain electrode of the MOS tube Q2 is connected between the source electrode of the MOS tube Q5 and the drain electrode of the MOS tube Q6 through an inductor L2, a capacitor C2 and an inductor L3 in sequence, a position between the source electrode of the MOS tube Q3 and the drain electrode of the MOS tube Q4 is connected between the source electrode of the MOS tube Q5 and the drain electrode of the MOS tube Q6 through an inductor L1, the capacitor C2 and the inductor L3 in sequence, and the capacitor C2 is connected with a load R1 in parallel.

The invention discloses a building energy-saving monitoring system supplied with solar energy. The building energy-saving monitoring system is characterized by being mainly composed of a photovoltaic power generation system and a building detection system connected with the photovoltaic power generation system; the photovoltaic power generation is composed of a solar photovoltaic battery pack, a storage battery connected with the solar photovoltaic battery pack and an inverter system connected with the storage battery; the building detection system is composed of a processing module and a storage, a temperature sensor, a humidity sensor, a smoke sensor and an alarm which are connected with the processing module; the inverter system is connected with the processing module. The building detection system is powered by photovoltaic power generation, the photovoltaic basis is sufficiently utilized, the building operation cost is lowered, and the building energy-saving monitoring system is suitable for wide popularization. Various parameters in a building are collected through a multi-way data sensor, various kinds of monitoring working can be performed at the same time, and the building energy-saving monitoring system has the advantage that detection data is comprehensive, and improves the building intelligent level.

In a method for operating an inverter system and a corresponding inverter system, which includes from the network filter to the inverter, values are determined using the data unit, and a value spectrum of the determined values is determined using an evaluation unit. The value spectrum is compared to a predetermined or predefinable limit spectrum using an assessment unit, and a switching frequency of the inverter can be adapted while in operation by using an adapter unit arranged downstream of the data unit, the evaluation unit and the assessment unit in the return path.