基于单元串联多电平高压变频器的异步电机直流制动研究

DC Brake Research on Asynchronous Motor Based on High-Voltage Converter with Cells Cascaded Multilevel

简单地介绍了单元串联多电平变频器的结构,详细地阐述了直流制动的原理和具体实现的方法。提出了在具体实现制动时应考虑的3个主要因素,通过改进的电压控制方法,抑制了制动电流冲击波的产生,能够有效平滑地进行直流制动。试验结果证明,采用直流制动功能是可靠和有效的。直流制动特别适合在低频段制动,所以很适合于风机起动前确保拖动系统从零速开始起动所需的制动场合。

The system configuration was introduced simply. The operation principle and design method of DC brake were discussed in detail. Three factors were mainly considered in the braking operation. Through the improved control method of voltage, the abrupt change of output brake current was avoided. It can achieve DC brake smoothly. Experimental results proved that the applied braking method the reliable and effective and specially fit for braking in the low frequency. In order to making sure the fan was stop before starting, the DC braking was usually used.