The invention relates to the technical field of detection, in particular to a relay failure detection device and a relay failure detection method for a grid-connected inverter. The device comprises a relay module 1, a driving module 2, a control module 3, a first signal acquisition module 41 and a second signal acquisition module 42, wherein one end of the relay module 1 is connected with an output end of an inverter 5, and the other end of the relay module 1 is connected with a power grid 6; the driving module 2 is connected with the relay module 1; one end of the first signal acquisition module 41 is connected with the output end of the inverter, and the other end of the first signal acquisition module 41 is connected with the control module 3; one end of the second signal acquisition module 42 is connected with the power grid 6, and the other end of the second signal acquisition module 42 is connected with the control module 3; and the other end of the driving module 2 is connected with the control module 3. By the invention, turn-off or turn-on failure of any one or more relays in the relay module 1 can be detected, a detection result is fed back to a user through a display module, and the reliability in relay redundancy design of an output stage of the inverter 5 is improved.

Relay failure detection device and method for grid-connected inverter

Intelligent solar cell component and control method of array thereof

The invention discloses a high-frequency high-voltage electrostatic dust removal power control system and method. The power control system takes a DSP (digital signal processor) as a system core controller; external input signals are divided into analogue input signals and digital input signals; the analogue input signals are directly input into the DSP through a data acquisition part; the digital input signals are input into the DSP after being subjected to logic processing by a CPLD (complex programmable logic device); control signals output by the DSP are also output after being subjected to logic processing by the CPLD; the communication between a power system and an upper computer is realized through RS232/485 and CAN (controller area network) communication modes. The control method mainly comprises a secondary current and voltage flashover control method, a resonant current flashover judgment method and a best flashover rate control method. By the system and the method, the power output can be controlled effectively in real time according to the change of a load, the power efficiency is improved on the premise of guaranteeing the stable and reliable operation of a power supply, and a good dust removal effect is achieved.

High-frequency high-voltage electrostatic dust removal power control system and method

Photovoltaic grid-connected inverter and control method thereof

Provided is an island detection method. A passive method and an active method are matched, an island can be detected out fast according to an overfrequency/underfrequency and an overvoltage/undervoltage method, and the quality of electric energy is not affected; when islanding occurs and power matching is formed in an island system, power matching of the system can be destroyed according to a capacitor switching method with harmonic detection as a criterion, voltage and frequency in the system are made to change, and consequently the island is detected out.

Island detection method

The invention relates to a high-frequency high-voltage switching power supply for electric precipitation. Three-phase alternating-current is input and converted into direct current by a three-phase rectifier filter circuit and then the direct current passes through a high-frequency inverter circuit; a series-parallel connection resonant soft switching circuit is connected between two inverter bridge arms in the high-frequency inverter circuit; the output of the series-parallel connection resonant soft switching circuit is boosted by a high-frequency pulse transformer, the boosted output passes through a high voltage silicon rectifier stack to form high-voltage direct current and the high-voltage direct current is input into an electric precipitator; a DSP controller outputs a control signal to the high-frequency inverter circuit; the input side of the electric precipitator is connected with a voltage and current detection circuit; the detection circuit detects voltage and current and inputs a signal into the DSP controller; the high-frequency inverter circuit is adjusted by the DSP controller; and the DSP controller is connected with an upper computer through a CAN interface so asto realize optimal control. The switching power supply is used for electric precipitation equipment and has the advantages of small volume, light weight, light harmonic pollution, high power factor, high conversion efficiency, and capability of generating waveforms meeting various working condition requirements of the electric precipitation equipment so as to realize energy conservation and emission reduction.

High-frequency high-voltage switching power supply for electric precipitation

The invention relates to a three-phase photovoltaic grid connected inverter system. The three-phase photovoltaic grid connected inverter system comprises a DC/DC converting circuit which takes a photovoltaic array as an input power source, a Z source network, a DC/AC converting circuit which converts direct current (DC) into alternating current (AC), and a control circuit of the DC/DC converting circuit and the DC/AC converting circuit, wherein an output end of the DC/AC circuit is merged into an electric network; the control circuit takes a TMS320F2812 as a digital control system; and a closed-loop control system is formed by using various sensors and the digital control system based on the TMS320F2812. The three-phase photovoltaic grid connected inverter system can be applied to photovoltaic power generation systems, and can greatly improve the power generation efficiency of the photovoltaic systems, reduce the cost, output stable current with less harmonic content, and ensure safe and normal operation of the electric network.

Three-phase photovoltaic grid connected inverter system

The utility model relates to a permanent magnet direct-drive wind power generation system, which comprises a permanent magnet direct-drive synchronous generator, a rectification module, a boost chopper module, an inverting module and the like, wherein the permanent magnet direct-drive synchronous generator comprises blades and is used for converting wind energy blowing to the blades into electric energy; the rectification module is electrically connected with the permanent magnet direct-drive synchronous generator and is used for rectifying the electric energy; the boost chopper module is electrically connected with the rectification module and boosts the rectified electric energy by a three-phase three-switch three-level boost circuit; and the inverting module is electrically connected with the boost chopper module and is used for providing the boosted electric energy to a power grid or load, so the output current of the generator can be sinusoidal, the temperature rise of the generator is reduced, the service life of the generator is prolonged, the voltage withstanding grade of a harmonic wave and a main switching tube is reduced, and the efficiency and the stability of the wind power generation system are effectively improved.

Permanent magnet direct-drive wind power generation system

The utility model relates to a three-phase photovoltaic grid-connected inverter based on Z sources, which comprises a DC/DC converting circuit, a Z source network, a DC/AC converting circuit and a control circuit of the DC/DC circuit part and the DC/AC circuit part, wherein the DC/DC converting circuit uses photovoltaic arrays as an input power supply, the DC/AC converting circuit is used for converting DC into AC, and the output end of the DC/AC circuit is connected into an electric network The control circuit uses TMS320F2812 as a digital control system, and forms a closed loop control system with the digital control system based on the TMS320F2812 through various sensors The utility model uses a photovoltaic electricity generating system, can greatly improve the electricity generation efficiency of the photovoltaic system, reduces the cost, outputs stable electric current with low harmonic content, and ensures the safe and normal operation of the electric network

Zhihui Jin

Papers

High-frequency high-voltage switching power supply for electric precipitation

Three-phase photovoltaic grid connected inverter system

Permanent magnet direct-drive wind power generation system

Three-phase photovoltaic grid-connected inverter based on Z sources