SST-PFB-CLX Automatic Reactive Power Compensation System

SST-PFB-CLX developed a new generation of industrial control devices based on microcomputer technology, its structure is basically the same as the microcomputer form, small PLC is designed to replace the traditional relay contact control system and other sequential controllers, so it is also different from the hardware of a general-purpose microcomputer. It is the advantages of relay control, and the computer’s full-featured, flexible, versatile combination of computer programming software logic instead of relay wiring logic of the universal automatic control ready. It is an ideal new type of industrial control device.

SST-PFB-CLX has reformed the reactive power automatic compensation system of Dagang oil refinery, and designed the programmable controller (PLC) reactive power automatic compensation system on the basis of the original compensation equipment assembled with discrete components. The main circuit, phase angle detection circuit, output circuit, and voltage regulator of the original system continue to be used, while the control functions of the hardware circuits such as additive level conversion and delay circuit, subtractive level conversion and delay circuit, clock pulse generator, reversible counter, zero clearing circuit, decoder, and so on, are realized by PLC.

The output signal of SST-PFB-CLX phase angle detection circuit is weak and not enough to drive the input of PLC, so the signal has to be amplified and processed as the input signal of PLC. According to the control requirements of the system, the software of PLC is used to realize automatic control. The triode switching circuit in the original output circuit is realized with the output relay of PLC. Due to the limitation of PLC output point capacity, intermediate relay is added as output circuit.