铁路客车单相逆变器并联控制方法研究

Research on Parallel Control Method of Single Phase Inverter for Railway Passenger Cars

针对内燃机车改造为电力机车过程中,单相逆变器工作时间变长、可靠性要求更高且不间断供电等要求,提出一种单相逆变器并联控制方法,在一台单相逆变器内部设置两个不分主次、完全相同的模块进行并联工作,单模块故障后不影响整机输出。从电路拓扑、控制策略及调制方式等方面对并联控制方法进行了介绍,分析了无互联线并联控制原理,采用二阶广义积分器对电压电流进行重构,重构同时完成了滤波及相位跟踪。采用新型功率计算方法,仅需一个采样周期即可完成功率计算,减小了计算量及控制延时,提高了并联系统的稳定性和动态性能。最后以AC380 V电源装置为对象进行了仿真分析和试验验证,结果表明并联控制方法能够有效实现单相逆变器的锁相并网及负载均流,提高了单相供电系统的可靠性。

In the process of transforming diesel locomotive into electric locomotive, the working time of single-phase inverter becomes longer, the reliability requirement is higher, and the power supply is uninterrupted. A single-phase inverter parallel control method is put forward. Two identical modules, regardless of primary and secondary, are set up in a single inverter to work in parallel, and the output of the whole machine will not be affected if a single module fails. The parallel control method is introduced in detail from the aspects of circuit topology, control strategy and modulation mode. The principle of parallel control without interconnected lines is analyzed, and the voltage and current are reconstructed by a second-order generalized integrator, and the filtering and phase tracking are completed at the same time. Using a new power calculation method, the power calculation can be completed in only one sampling cycle, which reduces the calculation amount and control delay, and improves the stability and dynamic performance of the parallel system. Finally, the simulation analysis and experimental verification are carried out with AC380 V power supply device as the object. The simulation and experimental results show that the parallel control method can effectively realize the phase-locked grid connection and load current sharing of single-phase inverter, and improve the reliability of single-phase power supply system.