Abstract

This paper presents the simple and low-cost design of an automatic power factor correction (APFC) system for single-phase domestic loads. The proposed design uses TRIACs to switch the capacitor banks in order to correct the power factor of inductive loads. TRIACs are more effective than electro-mechanical relays and hit the high-performance benchmarks. An Arduino board controls the switching of TRIACs. The Arduino is programmed to non-stop monitor and calculate the power factor of the connecting load by sensing the signal from CT, PT and Zero Cross Detectors (ZCDs), and keep the power factor of the load above the reference value (0.95) by appropriately energizing the capacitors in parallel to the connecting load through TRIAC switching. The value of power factor before and after improvement is displayed on LCD. The hardware prototype of the proposed APFC design is also developed to validate its operation. The satisfactory and acceptable results of the APFC system testing have confirmed that the suggested design yields a reliable output and can be further used in any single-phase practical application to ensure the power factor close tounity.