摘要
结合锁相环的原理研究,利用DSPTMS320F240实现高精度锁相的数字锁相环的原理与方法。所给出的锁相方法中利用DSP的捕获中断和周期中断读取市电和逆变输出的相差,经数字PI调节器输出一个载波周期的补偿量,通过动态改变载波周期值实现逆变输出对市电的锁相,理论上相位差分辨率可高达0·72°。分析了相位关系的判断方法,给出了相位跟踪的硬件实现电路及程序流程图。实验结果验证了该方案的可行性和有效性。
The principle and realization method of DPLL (Digital Phase Lock Loop) with high precision by DSP TMS320F240 is presented. The phase error between UPS and electrical network is measured by CAP interrupt and Period interrupt of DSP. A digital PI controller is applied to supply a compensation value for every carrier period. The dynamic tracing of inverter output to electrical network is realized by changing carrier period. The theoretic resolution of phase error is 0.72 degree. The judgement method of phase relation is analyzed. The circuit and the flow chart of program are given. Experiment result proves the scheme is feasible and effective.
出处
《电气应用》
北大核心
2006年第2期66-68,共3页
Electrotechnical Application