Research And Implementation Of Periodic Measurement Based On Time Integration

The purpose of this paper is to study a new type of device detection based on integral cycle timing,the timing control device can record results for the integral integrator and the zero time point to achieve the measurement of periodic signals through software programming.It is a very practical problem to optimize the anti-jamming of periodic detection.This paper hopes to find a cycle easy detection method can significantly improve the detection accuracy,improve the anti-interference ability;hope to design hardware device through a simple software algorithm and high precision detection instrument with high accuracy cycle.Integral using the traditional zero crossing signal acquisition method,high precision sine wave frequency of the signal,the method of harmonic measurement in time,but to signal the presence of harmonics,the integral starting point affected by noise resulting in measurement results have certain error;digital frequency measurement method is affected by the traditional voltage measurement error and there are some errors.In this paper,we propose a method to measure the periodicity of periodic signals.The method is based on timing integration.In this paper,we also implement the simulation timing integration algorithm and the digital timing integration algorithm.The specific step of the simulation integration algorithm is to initialize the Miller integrator so that the voltage output value of the Miller integrator is 0,and then use the interpolation method to obtain the start time of the Miller integrator integral,and then control the integral circuit to start integrating,When the integrator output value becomes zero again,the control integration circuit stops the integration and records the integration end time to calculate the zero-crossing point,and repeats the above steps to obtain a plurality of zero-crossing points to calculate the cycle frequency of the periodic signal.Digital time integration algorithm is to realize the simulation of digital integral algorithm,the signal will be tested for A/D sampling and buffering,integral to deal with the data,after the calculation of zero points,the final calculation of the signal cycle.The research on the periodic detection device based on timing integral is the main work of this paper,including the selection of the measurement and control system and the overall design of the system and the hardware design of the system.The hardware part includes DSP control circuit,periodic measurement circuit,signal acquisition unit,Schmitt trigger,liquid crystal display circuit and microprocessor.The software part includes frequency measurement algorithm,signal integral control algorithm,signal acquisition method,CPU interrupt control algorithm.Finally,make thephysical,using the experimental device to verify the accuracy of the new method and reliability.The system requires the realization of the timing control of the integrator and the measurement of the periodic signal frequency.After the system is powered up,the DSP initialization operation is performed first.This process involves initializing the system function,interrupting the CPU interrupt,clearing the CPU interrupt flag,initializing PIE control register and other operations.In the calculation of the various parameters need to be stored in the DSP's internal memory,and finally calculate the results obtained through the LCD intuitive display.The algorithm does not need to convert the low frequency signal into square wave,especially suitable for low frequency sinusoidal signal frequency measurement,the system detection is convenient,the hardware cost is small;The system has strong anti-interference ability;The realization is simple and reasonable,the data is accurate and reliable.