Modeling and Filter Design for Overvoltage Mitigation in a Motor Drive System with a Long Cable
Modeling and Filter Design for Overvoltage Mitigation in a Motor Drive System with a Long Cable
复制标题
长电缆电机驱动系统过压缓解的建模和滤波器设计
DOI：
10.1541/ieejias.129.844
复制
发表时间：
2009
期刊：
影响因子：
--
通讯作者：
H. Akagi
中科院分区：
文献类型：
--
作者：
Itaru Matsumura;H. Akagi
本文深入讨论了可调速电机驱动系统的建模，该系统由电压源 PWM 逆变器和感应电机组成，并通过带有接地线的三相对称长电缆连接。然后，描述了每相并联 R-L 滤波器的设计过程，该滤波器可以减轻电机端子处出现的过电压。本文开发的模型重点关注电缆固有的“振铃频率”，其中振铃频率与电缆长度成反比。当不使用滤波器时，所谓的“阻抗失配”会导致电压行波在逆变器和电机端子处反射。因此，阻抗失配会产生过电压，该过电压可能达到电机端子处逆变器直流母线电压的两倍。过电压可能会损坏电机绕组绝缘，并可能导致其击穿。虽然在逆变器交流侧安装R-L滤波器可以降低过电压，但针对不同长度的长电缆，有效设计滤波器会很困难。本文描述的简单设计过程的有效性和有效性在具有 100 米或 200 米长电缆的 400 V、15 kW 实验系统上得到了证实。
This paper presents an intensive discussion on modeling an adjustable-speed motor drive system consisting of a voltage-source PWM inverter and an induction motor that are connected by a three-phase symmetric, long cable with a grounding wire lead. Then, it describes a design procedure for a parallel-connected R-L filter in each phase that can mitigate the overvoltage appearing at the motor terminals. The model developed in this paper focuses on the inherent “ringing frequency” of the cable, where the ringing frequency is inversely proportional to cable length. When no filter is used, the so-called “impedance mismatch” causes the reflection of a voltage-traveling wave at both the inverter and the motor terminals. As a result, the impedance mismatch generates an overvoltage that may reach twice the inverter dc-link voltage at the motor terminals. The overvoltage may damage the motor-winding insulation, and may cause it to breakdown. Although an R-L filter installed on the ac side of the inverter can reduce the overvoltage, it would be difficult to design the filter effectively for long cables of different lengths. The effectiveness and validity of the simple design procedure described in this paper are confirmed on a 400-V, 15-kW experimental system with either a 100-m or 200-m-long cable.