A method for measuring the economic efficiency of using a frequency converter in sewage pump plants

Frequency converters have gained in popularity over the last few decades and are widely used in many modern engineering lines. While the introduction of frequency converters in pumping installations theoretically allows for a simple solution to wide range of technical-engineering problems, in reality, these devices are often misused, negating the possible benefits. The problem is particularly acute in sewage line design. Being a major consumer of energy, sewage pump plants are equipped with ordinary pump units with no frequency converters, essentially working the same way they did half a century ago. Rare cases of such implementations show mixed results, further slowing the development of this area, and questioning the viability of frequency converters. In order to solve this problem and measure their economic efficiency, the physical parameters of the automatic control of sewage pump plants have to be established. According to the study, the power required can be reduced, and based on the proposed algorithm a method for calculating savings has been developed. The method takes into account the behavior of actual pump plants and the technicalities of pump units, thus providing for the versatility and thoroughness of its application.