兰州交通大学 自动化与电气工程学院
TM922??????
国家自然科学基金项目（面上项目，重点项目，重大项目）；甘肃省自然科学基金重点项目；甘肃省自然科学基金项目
School of Automatic Electrical Engineering,Lanzhou Jiaotong University
随着新能源发电比例的增加及外部电网低惯量特性愈加显著,传统的牵引供电系统缺乏有效的惯量响应能力,导致牵引供电系统面临频率稳定性挑战。针对上述问题,本文提出一种储能式虚拟同步铁路功率调节器(Energy Storage Based Virtual Synchronous Generator Railway Power Conditioner, ES-VSG-RPC)控制策略。首先,分析ES-RPC动态补偿负序电流和谐波电流的基本原理,研究电流补偿控制策略。接着,根据左右供电臂负荷功率与频率,提出一种计及负荷权重的系统频率,将牵引供电系统等效为单区域供电系统。然后,通过联立同步发电机摇摆方程与超级电容功率方程,利用系统频率控制储能装置的有功功率,模拟同步机惯量响应过程,提出一种ES-VSG的DC-DC控制策略。最后,通过在MATLAB/Simulink中搭建时域仿真模型,验证ES-VSG-RPC控制策略在牵引供电系统典型工况下的有效性。结果表明,ES-VSG-RPC在低惯量牵引供电系统中,既保证电能质量的动态补偿,又能动态控制储能的充放电功率,提高牵引网的频率稳定性,支撑其动态运行。
With the increase of the proportion of new energy power generation and the low inertia characteristics of the external power grid, the traditional traction power supply system lacks effective inertia response ability, which leads to the frequency stability challenge of the traction power supply system. In view of the above problems, this paper proposes an energy storage based virtual synchronous generator railway power conditioner (ES-VSG-RPC) control strategy. Firstly, the basic principle of ES-RPC dynamic compensation of negative sequence current and harmonic current is analyzed, and the current compensation control strategy is studied. Then, according to the load power and frequency of the left and right power supply arms, a system frequency considering load weight is proposed, and the traction power supply system is equivalent to a single-area power supply system. Then, by combining the swing equation of synchronous generator and the power equation of super capacitor, the active power of energy storage device is controlled by system frequency, and the inertia response process of synchronous generator is simulated. A DC-DC control strategy of ES-VSG is proposed. Finally, the time domain simulation model is built in MATLAB/Simulink to verify the effectiveness of ES-VSG-RPC control strategy under typical working conditions of traction power supply system. The results show that in the low inertia traction power supply system, ES-VSG-RPC can not only ensure the dynamic compensation of power quality, but also dynamically control the charging and discharging power of energy storage, improve the frequency stability of traction network and support its dynamic operation.
