Design of Intelligent Commutation Switch System Based on HPLC Carrier Scheme

China's low-voltage transmission lines are mostly three-phase four-wire power supply networks. Due to the large number of single-phase power users which are dispersedly located, there are different levels of three-phase load imbalance problems in most distribution areas. With the improvement of the national economy, the electricity consumption at the grassroots level has increased, and the problem of unbalanced three-phase loads of the low-voltage power grid has become increasingly prominent. The article introduces a product which can handle unbalanced three-phase problems in the low-voltage distribution area. It can quickly and accurately detect the three-phase unbalance problem of the low-voltage distribution system. The three-phase intelligent commutation switch system can adjust the single-phase load without power cut in real time ensuring that the three-phase load in the station is in a relatively balanced state. This product can effectively reduce transformer loss and line loss caused by three-phase load imbalance, and avoid single-phase over-current, terminal low-voltage, etc. It can also prevent numerous safety hazards caused by three-phase unbalance. This paper introduces the harm of three-phase unbalance, the working principle and system of the commutation switch, and the advantages of the HPLC scheme to highlight the intelligence and program advantages of the commutation switch.