Frequency changer control circuit and several kind of common fault analysis[ Steven W. Blume. 《Electric Power System Basics For The Nonelectrical Professional》.2007年10月出版
.Wiley-IEEE Press ]
1． Introduction
Along with the frequency changer in the industrial production the widespread application, understood day by day the frequency changer the structure, the main component electrical specification and some commonly used parameters functions and its the common breakdown are more and more important regarding the practical work. 2. Frequency changer control circuit
Provides the control signal to the asynchronous motor power supply main circuit the return route, is called the control circuit. The control circuit by the frequency, the voltage arithmetic circuit, the main circuit voltage, the electric current examination electric circuit, the electric motor speed examination electric circuit, the arithmetic circuit control signal will carry on the enlargement the actuation electric circuit, as well as the inversion and the electric motor protection circuit and so on will compose.
Increased the speed examination electric circuit in the control circuit, namely increases the speed instruction, and may carry on the more precise closed-loop control to the asynchronous motor speed.
(1) The arithmetic circuit instruction and so on exterior speed, torque with will examine the electric circuit the electric current, the voltage signal carries on the comparison operation, will decide the inversion output voltage, the frequency.
(2) The voltage, the electric current examination electric circuit for isolates the examination voltage, the electric current with the host return route electric potential and so on.
