Power quality monitoringdeviceWhat are the measurement methods available?

1. Regular inspections.

Mainly suitable for situations where it is necessary to master power quality without continuous testing, or where continuous online monitoring conditions are not available.The power quality inspection of power distribution points in residential, commercial, and small factory power supply systems is generally conducted once a month or quarter based on the importance level, and detailed records should be kept and archived.The instruments used for regular inspections are mainlyPortable power quality analyzer, or handheldPower quality analyzer。For power grids without impact loads and situations where the load changes within the power supply range are not significant, the impact of voltage fluctuations and flicker is minimal or non-existent. The indicators of voltage fluctuations and flicker generally do not require online continuous monitoring, and regular testing is usually conducted once every six months or once a year to meet the requirements. For power grids with impact loads, testing is generally conducted once a quarter or a month, depending on the specific situation. The testing instrument is a flicker meter or a portable power quality analyzer.

2. Online monitoring.

Online continuous monitoring can be implemented for public distribution points in important substations or unmanned substations, or for distribution points of important power users. Online detection is mainly applicable to monitoring the voltage quality deviation, three-phase voltage imbalance, voltage harmonics and other states of the power grid, as well as indicators such as harmonic current and negative sequence current injected by power user loads into the public power grid. The monitored items include: power supply frequency, voltage deviation, three-phase voltage imbalance, negative sequence current, active power, power factor, grid harmonics, etc.Power quality monitoring deviceThe functions of online monitoring include: data display function, data storage function, data remote transmission function, and the function of exceeding limit alarm or issuing control commands for monitoring project control standards. Real time monitoring data, historical change curves, indicator limit exceeding alarm signals, etc. can be displayed on site and remotely monitored through computer networks.

3. Special testing.

Mainly used in situations where there is a significant change in load capacity or interference source equipment is connected to the power grid, or there is a temporary reflection of abnormal power quality that needs to be compared before and after changes, in order to determine the background situation of power quality indicators in the power grid and the actual parameters of load changes and interference, or to verify the effectiveness of technical measures. The special testing work can be cancelled after completing the scheduled task. Used for special testingPower quality monitoring deviceGenerally, it is a portable power quality analyzer.