Study On The Measurement System Of AC Electrical Paramenters Of Non-Sinusoidal Waveforms

In this paper, we study on the digital measurement of AC electrical paramenters of non-sinusoidal waveforms.We can measure the frequency,effective values of voltage and current, active power and power factor by the measurement system.In this paper, the AC sampling and calculate computation theory is introduced, and software synchronous sampling is used to the AC sampling measurement.We analyze the main reason of the synchronization error in measuring,and the improved measures are discussed base the error analysis,including the selection of the sampling number N,sampling start point a,using repair integral with rule of three,and also studyv on the differrent digital samples for the signal with differrent frequency,From the result of emulation,we can find the synchronization error in measuring and it's affect to the result are reduce by the improved measures,so the measure accuracy can be improved effectively.After method study,We design the measurement system of AC electrical paramenters of non-sinusoidal waveforms, use the 16 bit mixed signal micro-controller(MSP430F449) with low power consumption.The hardware of whole system is made of three main parts,include micro-controller part, analog signals input part and peripheral equipment part.The software design include sampling, calculation and LCD display.We carry out the experiment and the analyses of error.The methods and functions where we should improve are also discussed in this paper.The emulation and the experiment can indicate the validity of the improved measures.The digital measurement system of AC electrical paramenters of non-sinusoidal waveforms use AC sampling technology.Software replaces much hardware,which is simple in configuration and simplify the peripheral circuit,portability and rich in function.The numerical measurement have high accuracy for the AC electrical signal and also have good practicality.