潜油电泵变频驱动负面问题研究

变频器驱动潜油电泵存在一些缺陷,即需要较长的输电电缆传送至潜油电泵,增加了潜油电泵机组的故障率.根据均匀传输线模型及波的线路传输方程,分析了由此带来的波反射过电压振荡问题以及对输电电缆和电机绕组的影响.对变频输出共模电压及轴承电流的形成机理进行了研究,分析了其对潜油电泵轴承寿命的危害.合理地设计变频器及加装输出低通滤波器,可以有效地改善变频器的输出电压波形,从而抑制波反射过电压及轴承电流的产生,使潜油电泵正常运行.另外,输出低通滤波器可以滤出变频器输出中的高次谐波成分,有效地延长潜油电泵机组的使用寿命.

egative problems of electrical submersible pump driven by converter

The characteristics of the electrical submersible pump driven by converter were analyzed. The pulsewidth modulation converter of the electrical submersible pump has some harmonics in the output waveform. There needs a long cable from the converter to the pump. So it is easy to cause the reflected wave which will damage the cable and motor. By the transmission line theory, the generation mechanism of common-mode voltage and the bearing current was discussed. The adverse effects of common-mode voltage and the bearing current on the bearing life of the electric submersible pump were investigated. Some methods for solving those problems such as reasonable design of converter and building low-pass filter are given. The practicality of the proposed methods was validated by field case.