WATER PUMP UNIT POWER-SAVING OPTIMIZED OPERATION METHOD AND SWITCH POINT DETERMINATION METHOD

摘要

Provided are a water pump unit power-saving optimized operation method and switch point determination method. In parallel pump units, k water pumps of the same model equipped with frequency converters constitute a sub-pump unit A; using a constant-pressure operation mode, the water output Q1 of the first pump in the sub-pump unit A and a frequency converter input power P1 corresponding to Q1 and a frequency converter operating frequency f1 corresponding to Q1 are recorded, wherein QA = Q1 and PA = P1, to obtain a QA - PA curve of one operating water pump as an operating curve w1; taking QA = mQ1 and PA = mP1, m being a positive integer and k ≥ m ≥ 2, the operating curve wm of m running water pumps running at the same frequency, f1 = f2 = ... = fm is obtained; the point of intersection of the operating curve wm-1 and the operating curve wm is the optimal switch point between m-1 operating water pumps and m operating water pumps under constant pressure Hs. According to these optimal switch points, the number of pumps is switched and the speed is controlled, ensuring that the sub-pump unit A operates in a high-efficiency state.