Automatic Power Factor Controller using Raspberry PI

The project is designed to minimize penalty for industrial units by using automatic power factor correction unit with the help of Raspberry Pi. Power factor is defined as the ratio of real power to apparent power. This definition is often mathematically represented as KW/KVA, where the numerator is the active (real) power and the denominator is the (active + reactive) or apparent power. Reactive power is the non working power generated by the magnetic and inductive loads, to generate magnetic flux. The increase in reactive power increases the apparent power, so the power factor also decreases. Having low power factor, the industry needs more energy to meet its demand, so the efficiency decreases. Therefore, it can be seen that, to reduce the total current to the actual current required would result in greater efficiency. Power Factor values are in the range of 0- 1, hence an electrical system with a power factor of 1 (unity) is using 100% useful current with no inefficiency. However, an electrical system with a power factor of 0.5 (50%) is using twice as much current as it needs. In this proposed system the time lag between the zero voltage pulse and zero current pulse duly generated by suitable operational amplifier circuits in comparator mode are fed to the Raspberry Pi board. . It displays the time lag between the current and voltage on an LCD. The program takes over to actuate appropriate number of relays from its output to bring shunt capacitors into the load circuit to get the power factor till it reaches near unity. Automatic power factor correction techniques can be applied to the industries, power systems and also households to make them stable and due to that the system becomes stable and efficiency of the system as well as the apparatus increases. Index Terms - Capacitor Bank, Power Factor, A.P.F.C., Industrial Load