Design And Implementation Of Single-phase Power Quality Monitor Based On STM32

The power grid power supply quality faces great challenges due to more and more non-linear load and distributed new energy grid access.Seting up a good power quality analysis system,which draws more and more attention from the industry and academia,is a demand of smart grid and an effective way to improve power quality.To monitor the power quality with low cost,high accuracy and intelligence,this paper designs a single-phase power quality monitor based on STM32,which is suitable for power quality analysis in many occasions,such as home PV power generation,basement charge pile and single-phase electric workshop.Firastly,this paper explains the devwlopment of power quality monitoring at home and abroad,and analyzes the function requirement of power quality monitor according to the newest power quality monitoring standards in China.In this paper,we determined the static power quality parameters,which need to be measured by the single-phase power quality monitor,and designed the scheme of power quality analysis based on STM32 and professional power quality analysis chip RN8302.The harmonic detection scheme based on instantaneous var theory is simulated by MATLAB,which verifies the feasibility of detecting harmonics by using single-phase current phase shifting to construct three-phase current.Secondly,the paper emphatically introduces the design of the key hardware circuit of the single-phase power quality monitor,including the expansion board design,the main control board design,the communication system design and so on.Besides,the PCB manufacturing,soldering and debugging processes were also accomplished.Based on the embedded real-time operating system Rt-thread,this paper designs the embedded software of the monitor,which mainly include the m8302b data acquisition,harmonic analysis,encryption communication and IAP remote upgrade.Finally,the test experiments of the single-phase Power quality monitor were carried out,and the results show the feasibility of the proposed scheme.The designed single-phase power quality monitor can satisfy the analysis and real-time transmission of the single-phase power quality data,which satisfy all the design requirements,and has a great practical value and application prospect.