The impact of power quality problems on power system security can be analyzed from the primary and secondary systems respectively. For the primary system, power quality problems will worsen the operating conditions of the system equipment, and directly threaten the safe operation of the system. For example: harmonic may cause resonance, resonant high voltage is added to both ends of the capacitor, because the impedance of the higher harmonic to the capacitor is very small, so the capacitor is prone to breakdown due to overload. Negative sequence and harmonic not only have thermal effect on generator, but also cause vibration and noise, which seriously threaten the safe and stable operation of generator.

      For the secondary system, when the power quality problems threaten the safe operation of the system equipment, the protection part of the secondary system will automatically make the system equipment out of operation, which will lead to some unexpected results; on the other hand, the power quality problems may make the protection device misoperation, refuse to operate and other problems, thus causing serious consequences for the safe and stable operation of the power system Fruit.

The voltage fluctuation will make the motor speed uneven, endanger the safe operation of the motor, affect the product quality, cause the "flicker" of lighting, make the human eyes tired and reduce the work efficiency.

If a computing center loses power for 2 seconds, it may destroy the data processing results of dozens of hours and cause millions of yuan of economic losses. In large machine manufacturing plants, the sudden drop of voltage for 0.1s may cause abnormal production conditions and quality damage.

All these problems are caused by power quality problems. Therefore, it is necessary to strengthen the monitoring and governance of power quality, whether from the needs of power grid operation or from the needs of users for power quality. The smr-em series power quality online monitoring device produced by our company is a high-end power quality data acquisition, analysis, storage and transmission online monitoring terminal to meet the intelligent demand. It can provide customized power quality monitoring scheme for users to adapt to various application scenarios.