基于改进主从法的并联双向直流电源系统控制

The System Control of Parallel Bidirectional DC Converter Based on Improved Master-Slave Method

摘要:

随着各种用电设备容量的增加，对大功率电源的需求日益迫切。由于大容量的单体电源技术尚不成熟，因此多电源模块并联运行技术成为解决当前实际需求的有效手段之一。对于并联直流电源系统，提出了一种电源模块基于主从控制的数字均流改进算法。该算法在主从控制的基础上，通过限制主模块最大输出电流、电路启动时主模块采用软启动控制等技术，使输出电压分段上升，降低了并联电源主从控制中主模块出现故障和系统瘫痪的概率。针对不同电源模块的电路特性，设定系统响应时间慢的电源模块为主模块，并且设置从模块PWM调节速率大于主模块，可以降低PID参数对于每个电源模块调节稳定性和均流精度的影响，减少实际PID参数调试时间。实验结果表明，改进的算法可以实现较好的系统稳定性且均流精度高，均流误差低于1.5%，而且硬件电路设计简单。

Abstract:

As the capacity of various electrical equipment increases, the demand for high-power power supplies becomes more and more urgent. As the large-capacity single-unit power supply technology is not yet mature, parallel operation of multiple power supply modules has become one of the effective means to solve the current practical needs. For parallel DC power systems, it presents an improved digital average current algorithm based on master-slave control of power supply module. Based on the master-slave control, the algorithm limits the maximum output current of the main module and the main module adopts soft-start control when the circuit starts up, so that the output voltage rises step by step, which reduces the failure of the main module in the master-slave control of the parallel power supply, the probability of a system crash. According to the circuit characteristics of different power supply modules, the power supply module with slow system response time is set as the master module, and the PWM adjustment rate of the slave module is set greater than that of the master module, which can reduce the influence of the PID parameter on the stability of each power supply module and can reduce the actual PID parameter debugging time. The experimental results show that the improved algorithm can achieve better system stability and high current sharing accuracy. The average current error is less than 1.5% and the hardware circuit design is simple.