Research And Application In Energy-saving Circulating Water Pump Pole-changing Control System On Electric Power Plants

With the development of pole-changing control Technology，pole-changing controlTechnology been widely used in high voltage motor in energy saving. In the north of thepower plant, Because of the influence of circulation pump is affected by seasonaltemperature difference, Caused by the circulating pump efficiency of waste. This papermakes research on the principle of Vertical Wet pit Mixed flow pump, Starting fromthe control of circulating pump motor, After careful study of the foundation ofpole-changing control, Frequency conversion five kinds of AC speed regulation scheme,Combining characteristics of circulating pump, for the five scheme from the energy savingtechnology,Construction cost, on the contrast, Focuses on the study of circulation pumpmotor pole changing speed. In this paper, three kinds of The three circuit breaker, Singlecircuit breaker with local switch cabinet, Single circuit breaker of variable pole adjustablespeed control scheme is studied. At the same time, In high voltage motor polechanging process of transformation in Because the winding connection mode change,The differential current protection misoperation and electromagnetic noise motor wereanalyzed. And to formulate corresponding measures, In the double speed transformationexample of Jin Qiao thermal power plant circulating pump motor, From our factory reality,Analysis of the necessity of pole changing control of the circulation pump, In the analysisof comparison, The speed control mode of single circuit breaker, Combined withthe characteristic curve characteristic curve of pipeline and pump, The transformationof double speed motor speed and the number of poles. The variable pole adjustable speedratio of variable frequency speed regulation is more suitable for circulating pump, The highand low speed motor fixed value setting calculation. By optimizing the operation of steamturbine cold end, The operating strategy of double speed motor. Operation test of doublespeed motor field, The successful development of a motor6kV grade of variable poleadjustable speed system, The system is reliable and stable, Significant economic benefits.