A Method of Realizing Voltage Frequency and Phase Tracking Using ecap Interrupt

Abstract

The invention relates to a method achieving voltage frequency and phase position tracking by use of ECAP interruption. The method mainly comprises steps of converting sine waves of input voltage into square waves; inputting a square wave signal into an ECAP capturing pin of a controller, and calculating a periodic value zc of the square wave signal through the ECAP interruption; recording a phase position value of the output voltage of an inverter at the interruption occurrence period; defining a descending edge of the input square wave signal to be the zero phase position of the input voltage signal, and carrying out frequency phase position adjustment according to the periodic value and a phase position difference value so as to allow the frequency phase position of the output voltage to track the frequency phase position of the input voltage. According to the invention, software is used for carrying out frequency locking and phase locking, thereby carrying out tracking of the frequency phase position; the control method is flexible; a control system is simplified; use of simulation devices like a large number of resistors and capacitors is avoided; disadvantages of aging and quite high power consumption of simulation circuit devices are overcome; timeliness is achieved for the circuit; and disadvantages of lagging in control, proneness to suffering from interference and existence of phase position difference between the input voltage and the output voltage are overcome.

Description

technical field [0001] The invention relates to the technical field of voltage frequency and phase tracking, in particular to a method for realizing voltage frequency and phase tracking by using ECAP interruption. Background technique [0002] Usually, the quality of power generated by diesel generator sets cannot meet the requirements. It is necessary to use an online UPS to convert the power generated by the unit, and then provide the load with high-quality sine wave power with stable voltage, stable frequency and minimal waveform distortion. Tracking the frequency and phase of the input voltage is a key technology of online UPS. In order to ensure that the switching process of the inverter bypass does not cause excessive impact on the load, the inverter output voltage of the UPS must keep the frequency and phase of the input voltage. Therefore, it is necessary to ensure that the output voltage can track the frequency and phase of the input voltage through technical means....

AI Technical Summary

Problems solved by technology

[0003] In the prior art, an analog phase-locked loop circuit is usually used, but the circuit required for analog control is complex, the number of discrete components is large, and it is easily affected by temperature and electromagnetic noise

Although the dedicated analog control chip simplifies the control system, a large number of analog devices such as resistors and capacitors are still required in the feedback control network, which has the disadvantages of device aging and high power consumption.

However, the digital phase-locked loop circuit using AD sampling, due to the delay of the AD sampling circuit, and the error in the quantization and encoding process of the analog signal, the real-time performance of the digital phase-locked loop circuit using AD sampling is not good, the control lags, and it is easy to be affected. Interference, there is a phase difference between the input and output voltages

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