一种基于CPLD的编码器抗干扰电路设计

The anti-interference circuit design for encoder based on CPLD

在交流伺服系统中,准确可靠地获取编码器信号是整个闭环控制的关键;而编码器信号常受外界干扰,会产生误码脉冲,给伺服控制带来了偏差。在分析了增量式光电编码器的原理及误码产生原因、总结编码器信号处理方法后,设计了一种基于CPLD的具有编码器差分信号输入、误码滤除和鉴相功能的电路,提高了编码器信号检查的可靠性,并得到了很好的实际应用。具体分析了滤除误码原理,并给出了设计原理图和QuartusⅡ下的仿真结果。

In the AC servo system , accurate and reliable access to the encoder signal is the key to the entire closed -loop control . The encoder signals often subject to outside interference , resulting in the error pulse to the servo control deviation . After analysising the principle of incremental photoelectric encoder and error causes , summing up the encoder signal processing method , this paper designs a circuit based on CPLD , with a differential signal of the encoder input , error filter and the phase identification . That improves the reliability of the encoder signal check , and the circuit has a good practical application . The paper analyses the filter error principle , and gives the design schematics and simulation results under Quartus II .