A Novel Technique for Protecting Inverter From EMI and EMC Using PCB Based Spark Gaps

An electronic system must operate reliably within its designated setting, without inducing or experiencing electromagnetic interference (EMI) from other systems. A system that complies with these standards is viewed as electromagnetically compatible (EMC) with its surroundings. The primary objective of EMC is to ensure the safe, predictable, and interference-free operation of electronic equipment while complying with relevant regulatory standards. In sensitive environmental conditions such as lightning, high humidity, and harsh climatic events can detrimentally influence the performance of electronic equipment, including systems used in home inverter applications. For reliable and robust operation, especially in residential and semi-industrial settings, inverters must be capable of withstanding electrical transients up to 6 kV. Traditional surge protection solutions typically involve components like Metal Oxide Varistor (MOVs) and Gas Discharge Tubes (GDTs), which are effective for high-stress conditions (above 4 kV). However, the inclusion of GDTs significantly increases the cost of the EMI filter circuitry. To deal with these challenge, cost-effective on-board PCB spark gaps are presented in this paper. These spark gaps are formed using patterned copper areas directly integrated within the PCB layout, thus eliminating the need for expensive discrete components.