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.

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.

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 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.

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 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 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 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 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.