Short circuit is the most serious fault mode in switching power supply. The instantaneous large current caused by short circuit makes the circuit heat seriously, and even damages the device; Therefore, it is necessary to study the characteristics of short-circuit protection. Based on 100V high-voltage half bridge topology, this paper analyzes the short-circuit characteristic protection mode. In this paper, the small signal model of half bridge topology is established, the system characteristics under output short circuit are analyzed, and input-output overcurrent protection and output current limiting protection are proposed to reduce the impact of short circuit on the circuit.

With the development of space technology, satellite power supply system has higher requirements for circuit reliability, system efficiency and power density. In order to enhance the reliability of the circuit and improve the efficiency of the system, a maximum power point tracking (MPPT) circuit combined with shunt technology is proposed in this paper. When the circuit works at high power, it is in MPPT mode. With the reduction of power, the circuit will enter the shunt mode. In this paper, the principle of circuit mode switching is described in detail, and the feasibility of the control strategy is verified by simulation and experiment.

针对无线电能传输(wireless power transfer,WPT)系统处于不同负载、耦合系数和频率的运行状况进行分析,基于T型等效电路和二端口网络,得到了 SS、LCL和LCC 3种谐振网络的传递函数模型.将3种谐振网络的传输特性进行分析,实验结果表明3种谐振网络均为恒流输出,其中LCC网络具有随负载和耦合系数变化呈单调增的关系,有效地解决SS和LCL网络中存在传输功率过小等问题,并抑制系统处于偏谐振或低耦合状态下出现功率过载的情况.最后搭建了一台基于移相全桥(phase shift full bridge,PSFB)控制的LCC型WPT实验样机,能适应宽负载变化范围,当逆变器处于不同的移相角下均能保持零相角(zero phase angle,ZPA)的条件,使得系统具有较高的传输效率.

设计一种均衡电路以解决电池均衡的问题,并运用扩展卡尔曼滤波(EKF)估测电池的荷电状态(SOC).针对电池特性建立数学模型,采用脉冲放电实验法确定电池模型的各个参数,通过混合功率脉冲实验(HPPC)采集数据,用九次多项式拟合开路电压与SOC曲线图.由仿真结果可知,实验方法可准确地估算电池的SOC.

针对边防哨所的特殊性,以及风力发电和太阳能发电所存在的随机性、季节性和间歇性而引发的微电网系统的电压波动、功率波动等问题。为了维持微电网系统的电压、功率的输出稳定,保证微电网的稳定运行。通过以风光互补发电为形式的方法解决供电不稳定,并增加以铅蓄电池和热水为介质的混合储能单元,储能系统吸收和释放发电单元侧和负载侧之间的功率差值来平抑微电网的能量波动。在MATLAB/Simulink上建立带混合储能单元的微电网供电系统仿真模型,得到风力发电机、太阳能光伏阵列及储能装置的功率变化曲线,从而验证了混合储能控制策略的可行性。

In view of the problem of current distribution unevenness in converters caused by the fast charging of electric vehicles and the large power change of power batteries, swarm system consensus algorithm for multi charging piles to control cooperatively is proposed. Considering objective conditions that of communication topology charging pile nodes, information interaction weights and charging piles exiting system, the convergence characteristic of system is analyzed using graph theory. Then the control strategy of consensus algorithm is combined with voltage and current double closed-loop and the voltage and current states of multi charging piles reach consensus rapidly. The Matlab/Simulink results show that the proposed control strategy can effectively realize voltage constant and current sharing of converters. It has a certain theoretical significance for the rapid charging and replacing of EVs.