The Applied Research Of Variable Frequency Speed Regulation Technology And Energy Saving Assessment On The Condensate Pump Of Thermal Power Plant

In the thermal power plant,a large number of high power auxiliary system mostly uses traditional outlet baffle or valve closure adjustment,there are large amounts of electrical energy loss.In this paper,Datang Baqiao thermal power plant 2×300MW coal-fired unit as an example,the condensate pump system for frequency conversion.The working principle of the centrifugal condensate pump was introduced,and the saving space of condensate pump motor was analyzed after being transformed for speed regulation.HARSVERT-A06/065 high-voltage converter was selected to transform pump system in the constant pressure ratio control way during a thermal power plant condensate pump frequency inverter transformation process.Three condensate pumps with two sets of transducer in the power plant unit,can automatic switching operation in one for one and one with two.Bypass designed make sure that frequency and frequency switching operation was achieved.In connection with the burning phenomenon of condensate pump thrust segment in the debugging process,pressure difference of condensate pump balance drum and drive commissioning process were analyzed to figure out this problem.The main reason is as follows:first,pressure difference of condensate pump balance drum was increased when frequency conversion movement in a speed lower than safe speed which was established by condensate pump thrust pad film in stable status.Another one was due to that more lower speed of two condensate pumps have vaporization during parallel operation.In accordance with these reasons,some appropriate preventive measures were conducted.The commissioning results were very good,thrust watts burned or other security problems did not occur again.According to actual operating data from Datang Baqiao thermal power plant of 2 x 300MW unit condensate pump,which was transformed in high voltage variable frequency way,the amount of electricity of frequency control condensate pump consumed was smaller than that fixed frequency condensate pump did when the unit operated with same load before or after transformation.Motor starting current was reduced by the frequency control system,which is good for extending the life of unit.