Currently, with the advancement of science and technology, high-tech low-voltage electrical equipment is commonly connected to the power grid via power electronic interfaces. This includes devices used in industrial, agricultural, military, and consumer applications, such as inverters, energy-saving lamps, variable frequency air conditioners, computers, televisions, and more. The proportion of such electrical equipment in power grids is steadily increasing. These devices not only inject a large amount of harmonic distortion into the grid but are also affected by harmonics themselves. Since there are national standard limits for low-frequency harmonics (below the 29th harmonic), most electrical equipment can meet the national standard requirements. However, due to the high switching frequencies on the grid side, a large number of side-band frequencies exist, leading to the presence of high-frequency harmonics. These high-frequency harmonics create electromagnetic compatibility (EMC) issues and propagate in ways that primarily affect the control components of electrical equipment, such as microprocessors and digital and analog integrated circuits (ICs), causing control malfunctions and potentially catastrophic failures.
Additionally, electromagnetic pulses (EMP) and electrostatic discharges (ESD), generated by various phenomena such as operational overvoltage and lightning strikes, pose significant threats to microprocessors, digital, and analog chips. For example, major train operation accidents and rail transit incidents in southern China have resulted in billions of yuan in economic losses and serious negative international and domestic social impacts, all directly related to EMP and ESD. Furthermore, military equipment generates high-order harmonics that can easily radiate outward, leading to potential target exposure.
Our company has long been engaged in research on power grid quality control and testing. After years of dedicated research, we have developed the latest "Power Quality Protector." This device utilizes multiple filtering technologies (patented invention) and microcontroller-based fault detection and recording. It not only provides wide-band filtering for harmonics ranging from the 10th harmonic (500Hz) to over the 400,000th harmonic (20MHz), but also offers protection against overvoltage, EMP, and ESD. Moreover, the fault detection and recording system can monitor and log protection events. The device offers comprehensive power quality protection, particularly for precision instruments, preventing grid harmonics from entering electrical equipment while also stopping equipment-generated harmonics from being injected into the grid. This dual-functionality system ensures optimal protection for power networks and connected devices.