A Series Of Simultaneous Power Supply Buck DC Chopper Type Single-stage Multi-input Distributed Power Generation System

A variety of new energy sources such as wind power,photovoltaics,and tidal energy are favored in today ’s world where the environment is deteriorating and the resources are exhausted.However,single new energy power generation often has defects such as discontinuous power supply,instability,and high costs.For improving the continuity and stability of the power generation system,we need to uses multiple new energy sources.Therefore,innovation and research in the distributed power generation system of new energy combined power supply can integrate multiple energy sources,and has great theoretical research and economic value.This paper analyzes a single-stage parallel time-sharing distributed power generation system under the premise of systematically discussing the two-stage single-input and multiinput DC converter type new energy distributed power generation system,and proposes a series of simultaneous power supply Buck DC The chopper-type distributed power generation system introduces the circuit structure and topology family of the distributed power generation system in detail,and proposes a suitable energy management control strategy.Based on this,the single-stage of the distributed power generation system is discussed.The principle characteristics and circuit parameters of multi-input inverters and charge-discharge converters have obtained important theories.The circuit structure of Buck DC chopper type single-stage multi-input distributed power generation system with series simultaneous power supply is proposed and analyzed.It consists of a series DC Buck chopper-type single-stage multi-input inverter and power storage system connected in series The component charge-discharge converter is connected in parallel on the AC output side.The former is composed of multiple series connected simultaneous power switch circuits,combined bidirectional Buck DC chopper,active clamp circuit,and output filter circuit.The equivalent of a single-stage bidirectional full-bridge Buck high-frequency link rectifier / inverter.This paper presents and analyzes the control strategy of the maximum power output energy management of the multi-input source with independent control loop of the output voltage of the charge-discharge converter of the energy storage element charge and discharge converter of the Buck DC chopper series connected with simultaneous power supply,including Maximum power output energy management SPWM control loop of single-stage multi-input inverter and rectifier-like unipolar phase-shifting control loop of single-stage isolated bidirectional charge-discharge converter.Multi-input sources are output with maximum power,and the power flow size and direction of single-stage isolated bidirectional charge-discharge converters are controlled in real time according to the relative size of the AC load power and the maximum power of the multi-input sources,to achieve the stability of the system output voltage and three Smooth and seamless switching of power supply modes.The high-frequency switching process of the Buck DC chopper type with series simultaneous power supply is deeply studied,the key problem of suppressing the voltage spike caused by high-frequency transformer leakage inductance is proposed,and the multi-input inverter is established The small signal model of the converter and its control loop are designed,and the design criteria of key circuit parameters such as input / output filters,high-frequency transformer turns ratio,active clamp circuit and so on are derived.Designed and developed a 3kVA 220-260 VDC / 220V50 HzAC series simultaneous power supply Buck DC chopper type single-stage multi-input distributed power generation system prototype.PSIM simulation and experiment results have proved the correctness and feasibility of the distributed power generation system proposed by author.It has three power supply modes,simple circuit structure,single-stage power conversion in addition to energy storage element charging,high conversion efficiency,simultaneous power supply from multiple input sources,fast static performance and dynamic response,multiple input sources-energy storage elements-AC load three Electrical isolation,etc.,offer a new idea for jointly powered distributed power generation systems.