Method for controlling a regulated-rotation-speed low-pressure centrifugal fan

摘要

A method for controlling an automatic stall-prevention of a rotation-speed-regulated centrifugal fan. A control automatics is controlled by an automation system of the process wherein, the control automatics stalling is detected from a function of the electric current, voltage and frequency going to the motor of the centrifugal fan.

主权项

1. A method for controlling an automatic stall-prevention of a rotation-speed-regulated centrifugal fan, comprising the following steps:
controlling automatics by means of an automation system of a process, and detecting control automatics stalling from a function of the current, voltage and frequency going to a motor of the centrifugal fan; wherein the controlling is defined such that when U.I.N.(Tp/Tk)2/1000<0.0032 F2+0.1099 F+10.15, a valve is opened 5% from it's current position or U.I.N2.(Tp/Tk)2/1000>0.0032 F2+0.1099 F+10.15, the valve is closed 5% from it's current position; wherein U=supply voltage of the motor from a frequency converter I=supply current of the motor from a frequency converter F=supply frequency of the motor current N=hysteresis adjustment factor Tk=temperature in test conditions Tp=temperature of intake air.