Pump Control / Speed Control / AC Drives

The pump control can be optimized by using a frequency converter. The program controlled converter will take over pump control by fitting the rotation speed control of the AC drive and with it the engine output of the pump to the circumstances. A program like this can be altered at will. This can result in a huge savings capacity of energy. The frequency converter first transfers the power supply voltage to direct voltage in the intermediate circuit and then again into AC voltage. After this the frequency is variable. Thus pressure surges can be avoided and the AC drive can run out softly.
The motor pump is equipped with a pressure sensor. If water is pumped into a pressure container by the pump control the pressure sensor powered by the frequency converter is inserted in front of the pressure container. The main target is inserted behind the container. The working cycle is started by an operating switch. The speed control is parameterized ex works. A physical quantity, e.g. volume flow rate or pressure, is influenced by another quantity. A control like this is called open loop control because there is no feedback of the result. The result has no influence on the input quantity and the disturbances are not compensated. The frequency converter replaces the characteristic curve of the delivery rate and the delivery height typical for centrifugal pumps by a family of characteristics. In this family the pump can approach several duty points. This allows an optimal closed-loop control of the pump. It can be controlled by analogous signals. Different pressures can be achieved by several tools when a coolant pump for closed-loop control of a pump is controlled by a frequency converter.