ABSTRACT

ERICK DEPTHIOS. PIC16C55 Micro-controller-based Capacitor Bank Controller (supervised by Rhiza S. Sadjad and Indrajaya).

This is a research project to design a capacitor bank controller for household application using the PIC16C55 Micro-controller. The goal is to create a prototype of an automatic capacitor bank controller to increase the power factor. The project tasks are to determine the capacitor values of the bank, to set up a hardware configuration to control it and to write a program for the micro-controller.

A simple algorithm is applied to increase or reduce the capacitor values based on the measurement of current. The program automatically selects the best combination of 5 (five) values of capacitors, i.e. 5 mF/250 V, 10 mF/250 V, 21 mF/250 V, 41 mF/250 V and 64 mF/250 V, to minimize the load current.

Experiments show that the controller has successfully reduced the current of various inductive loads, while indicating the increase of the power factor of those loads. Resistive and capacitive loads are not affected. The controller has reduced the load current of the combination of home appliances such as an electric iron, a rice cooker and a water-pump as much as 0.02 Ampere indicating the increase of power factor from 0.91 to 0.97. The capacitor value for this combination of loads is 10 mF. The current of a highly inductive load such as air-conditioner compressor’s pump has been reduced as much as 1.49 Ampere indicating the increase of power factor from 0.88 to 0.97. The capacitor value for this load is 21 mF. 

The capacitor values selected by the controller have the largest error rate of 2.13% and the smallest of 0.82%. The average error rate is 1.58%.