Automatic Power Factor Correction for Single Phase Domestic Loads by Means of Arduino Based TRIAC Control of Capacitor Banks

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. The switching of TRIACs is controlled by an Arduino board. 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 (0.9) by appropriately energizing the capacitors in parallel to the connecting load through TRIAC switching. The values of power factor along with the current 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 to unity.