| The introduction of environment-friendly and sustainable economic development models has led to the closure of many old power plants,such as high-emission,high-pollution,and high-energy-consuming thermal power plants,The emergence of microgrid using clean energy sources such as landscapes as a raw material solves the above-mentioned problem.Microgrid,which is widely used in power generation networks,has also brought new problems.Quality of power is questioned and concerned.With the rapid development of science and technology,more and more sophisticated instruments appearing,people have put forward higher requirements for the quality of electrical energy.Good power quality is an important support for the rapid economic development.But bad power quality will affect the quality of industrial products and cause economic losses.The problem of power quality will also affect people’s quality of life,and even threaten life.Historically,there have been examples of small-scale fluctuations in the quality of power that have caused many people to lose their lives.Therefore,it is of great significance to monitor the power quality of microgrid.The traditional power quality measurement instrument,such as more advanced Zhou Ligong’s PA series PA2000 mini,PA7000,PA6000 etc.Their appearance provide good data support for the analysis and evaluation of power quality,but the traditional measuring instruments are generally large,the design of the hardware circuit is complicated and the measurement function has been set before leaving the factory.It is not easy to change in the later period,and the general development cycle is long and the cost is high which is not suitable for the monitoring of the power quality of the microgrid.This paper presents a Labview-based microgrid power quality monitoring system,which can solve the above problems.After in-depth study on the research status of microgrid power quality monitoring at home and abroad,combining the advantages and disadvantages of domestic and international research,this paper proposes a microgrid power quality monitoring system based on Labview.Analyzing the important parameters that affect the evaluation of power quality,such as the measurement of basic parameters,including the RMS frequency of voltage and current,frequency deviation,voltage deviation,three-phase unbalance,harmonic content,voltage fluctuation and flicker Wait for several indicators.In-depth analysis of each parameter index,investigating and analyzing the causes and hazards,referring to the relevant national standard documents of the power quality,we can list the national standard limits for each parameter index.After in-depth analysis,the hardware and software design of the system design is proposed,comparing different calculation methods for each parameter index.An algorithm that is most suitable for the system is selected to perform Labview program design.The design is explained in detail through mathematical expressions and program forms.In order to verify the feasibility and accuracy of the system to increase the persuasiveness of the system,firstly through simulation analysis,the theoretical and system measurements of the simulated signal are compared to verify the reliability and measurement accuracy of the system;after the simulation analysis,increasing the measurement experiment of PA2000 mini power analyzer.The instrument’s measurement experiment compares the power analyzer and system measurement results to verify the reliability of the system’s operating conditions and the accuracy of the measurement data.After the double verification analysis,it is concluded that the power quality monitoring system of microgrid based on Labview can overcome the disadvantages of traditional instruments while maintaining the measurement accuracy,and has the advantages of simple hardware design and the measurement function has the advantage of revise,and it can automatically store the measured data and read the historical data.It greatly facilitates the on-site measurement of power quality of microgrid and is of great significance for the monitoring and measurement of microgrid power quality. |
