Foreword
This document is drafted in accordance with GB/T 1.1-2020 "Standard Chemical. Work Guidelines Part 1: Structure of standardized documents and drafting rules".
Please note that some of the contents of this document may involve patents. The issuer of this document does not assume responsibility for identifying patents. This document is proposed and attributed by the National Technical Committee for Standardization of Voltage and Current Levels and Frequencies (SAC/TC1).
1 Scope
This document proposes the general rules of power quality monitoring, the data sources of power quality monitoring and the application of power quality monitoring data. This document is applicable to the power quality monitoring of AC distribution network.
2 Normative reference document
The contents of the following documents constitute the essential provisions of this document through the normative references in the text. Among them, note the date of the reference document, only the date of the corresponding version applies to this document; do not note the date of the reference document, its latest version (including all the revision of the list) applies to this document.
GB/T 14598.24 Measurement relays and protective devices Part 24: Power system transient data exchange (COMTRADE) common format
GB/T 17626.30 EMC test and measurement technology power quality measurement methods
GB/T 19862 General requirements for power quality monitoring equipment
GB/T 22239 Information security technology network security level protection wonderful basic requirements
DL/T 860 (all parts) Power automation communication network final ship system
DL/T 1297 Power quality monitoring system technical specifications
DL/T 1455 power system control class software security and its measurement technical requirements
DL/T 1608 Specification of power quality data exchange format
3Terms and definitions
The following terms and definitions are applicable to this document.
3.1
Power quality monitoring dedicated equipment
By analyzing and processing the introduced voltage and current signals, it is a special device to monitor the power quality index.
[Source: GB/T 19862-2016, 3.1]
3.2
Power quality monitoring master station
The application software with the functions of power quality monitoring data collection, analysis and management and its operation environment.
3.3
Power quality monitoring system power quality monitoring system
A system composed of power quality monitoring data source, communication network and monitoring master station.
[Source:GB/T 32507-2016,3.3,with modification]
4 Abbreviations
The following abbreviations are applicable to this document.
5 General rules
5.1 Basic general rules
5.1.1 According to the monitoring target and monitoring purpose to determine the power quality monitoring mode, monitoring point location, monitoring index, monitoring time length.
5.1.2 The function and performance of the power quality monitoring system should meet the requirements of DL/T 1297, and according to the monitoring target and purpose, choose long-term online monitoring or special test method.
5.1.3 It is appropriate to use special equipment for power quality monitoring or both power quality measurement equipment, measurement, statistical methods, etc. should meet the requirements of GB/T 17626.30. Power quality monitoring special equipment should meet the requirements of GB/T19862.
5.1.4 Monitoring data transmission, storage and use process should take the necessary information security protection measures. 5.2 Monitoring mode selection
5.2.1 Comprehensive consideration of application scenarios, monitoring costs and other factors in the selection of monitoring methods.
5.2.2 For distribution network power quality assessment, distribution network power quality abnormal analysis and other application scenarios, it is advisable to establish power quality monitoring system for long-term online monitoring, see Appendix A for typical power quality monitoring system architecture.
5.2.3 For the new energy field station of voltage level 10kV and above and the large-capacity interference source user power quality assessment and other application scenarios, it is appropriate to use long-term online monitoring method.
5.2.4 For the application scenario of power quality cycle census test of distribution network, special test method shall be adopted. 5.3 Monitoring point setting
5.3.1 Grid side monitoring point setting
6 Power quality monitoring data source
6.1 Monitoring data source classification
Monitoring data sources include special equipment for power quality monitoring, intelligent fusion terminal, insect energy meter, voltage monitor and other equipment with power quality monitoring function, as well as distribution network scheduling control system, distribution automation system, quality power information collection system and other data sources.
6.2 Monitoring equipment
6.2.1 Power quality monitoring function
6.2.1.1 Monitoring function should meet the requirements of GB/T 19862 and GB/T 17626.30.
6.2.1.2 For the distribution network monitoring application scenario where a large number of power electronic devices are connected, the monitoring equipment should have ultra-high harmonic monitoring function.
6.2.2 Communication function
7 power quality monitoring data application
7.1 You should combine the monitoring target to carry out the distribution network harmonic traceability analysis, voltage transient drop cause analysis, power quality economic assessment, capacitor resonance risk assessment and other monitoring data applications.
7.2 It is advisable to carry out harmonic traceability analysis for the problem of harmonic voltage exceedance, analyze the correlation of harmonic current and harmonic voltage based on the monitoring data, consider the topology of the power grid, the operation state of the main interference sources, correlation, etc. to determine the main harmonic sources and realize the analysis of the cause of harmonic exceedance.
7.3 It is advisable to analyze voltage transient amplitude, duration, phase jump and other characteristic information based on transient waveform data, classify voltage transient events based on characteristic information, carry out voltage transient source identification and positioning analysis, and clarify the cause of voltage transient (such as short circuit, motor start, lightning strike, etc.).
7.4 It is advisable to carry out economic assessment of power quality based on monitoring data, calculate additional losses caused by harmonics, three-phase imbalance and other power quality problems in combination with analysis models, assess the economic losses that may be brought to the distribution network or users by poor power quality, and propose energy-saving and loss reduction measures.
7.5 It is advisable to carry out online monitoring of power quality in capacitor branches where capacitor damage often occurs, and evaluate whether there is a risk of resonant operation by monitoring the harmonic current and harmonic voltage amplification in capacitor branches.
Appendix A (informative) Typical power quality monitoring system architecture
Appendix B (informative) Typical power quality disturbance sources and monitoring indicators
Appendix C (informative) MQTT communication protocol
Bibliography
Foreword
1 Scope
2 Normative reference document
3Terms and definitions
4 Abbreviations
5 General rules
6 Power quality monitoring data source
7 power quality monitoring data application
Appendix A (informative) Typical power quality monitoring system architecture
Appendix B (informative) Typical power quality disturbance sources and monitoring indicators
Appendix C (informative) MQTT communication protocol
Bibliography
