Three-Port Converter Topology And Derivation Research For Photovoltatic And Storage

With the rapid development of new energy,new energy needs to be combined with the traditional energy or energy storage devices.By this way,new energy sources can have a high efficiency,avoid the intermittent characteristics and improve power supply stability.In the new energy system,the photovoltaic and storage’s three port power conversion system has many applications.Due to the high degree of integration of the three port converter,the multi-sources access system can reduce the cost,simplify the system structure,and improve the efficiency and power density.The improvement of the degree of integration of the converter can realize the integration of control and improve the reliability.Based on the three port converter,this paper mainly s tudies the control strategy and the topology of the three port converter.The experimental verification of the control strategy and energy management strategy is presented for the proposed three port converter.Paper studies a novel optical storage system of three port converter(TPC),the TPC is the type of the direct power transmission(DET).The TPC has direct energy transmission unit,battery charging unit and battery discharge unit.This paper expounds on the structure of TPC and switch mode.On the basis of theoretical analysis and parameter calculation,the basic work mode of TPC is analyzed based on PLECS.Experiment of basic work mode is verified by the built 300 W prototype.According to the design idea of double frequency PWM,this paper proposes a novel control strategy based on multi-domain and double frequency PWM.On this basis,control program is designed based on the TMS320F2812.Through verification of MATLAB simulation platform and 300 W prototype based on the TMS320F2812,the control strategy can realize smooth switching among the shunt mode,battery charging mode,the battery discharge mode,the battery limiting charging current mode.With the combination of TPC topology and KY converter,a new co nverter is proposed which gain is 2D and can reduce the storage battery voltage grade.Based on the coupling inductance in the TPC topology and power path reconstruction,this paper proposes a quasi-Y source three port converter which can chieve high gain with duty ratio in the small scope.Control strategy based on multi-domain and competition is proposed which can achieve MPPT,storage battery charging and discharging management and bus voltage regulation.At last the control strategy has been verified by the system simulation based on PLECS.For the DET type three port converter,this paper proposes a three port converter based on Zeta and Superbuck.The proposed is single-stage converter topology between two ports.The integration of control program is p roposed to realize the energy exchanging between every ports.The control stragegy is conducive to the power extension of system.Frequency domain analysis and system simulation is carried out using PLECS,and 400 W prototype platform based on TMS320F28335 verifies the effectiveness of the control strategy and topology.