基于DSP锁相环的电动阀控制

DYNAMOELECTRIC VALVE CONTROL BASED ON DSP LOCKING LOOP

针对石油化工野外生产中广泛使用的直流电动阀设计控制系统。采用光电编码器检测电机的角速度和位移,利用数字信号处理器(DSP)构成数字锁相环(DSPLL),产生控制逻辑,调节PWM开关频率和占空比,改变电动机输入电压和电流,实现电动阀门开闭控制。系统能够根据阀门开闭位置、转速快慢、转矩大小,自动调节转速快慢和电机拖动转矩,确保电机转速、转矩最佳匹配。用ZY8024-200电机进行试验,结果证明控制系统响应速度快,精度高,系统谐波和文波幅度小;在转矩不断变化时,自动适应转矩变化,实现了直流电机保护功能。基于DSP锁相环的电动阀控制方案,特别适合于石油化工生产中野外直流供电的电动阀控制。

In this paper a control system is designed, which is aimed at DC dynamoelectric valve used in the petrochemical field production. It tests the rotating speed of motor and the displacement with photoelectric encoder and constructs digital phase-locked-loop based on DSP (DSPLL), which produces PWM logic and adjusts the frequency and dumpy to control the input voltage and input currency of DC motor. At last, it controls the valve to be open or closed. This system adjusts automatically the rotating speed and torque of DC motor according to the piston of the dynamoelectric valve, the rotating speed of DC motor and torque of load and ensures that rotating speed and torque of DC motor are optimal matching. Experiment with DC motor (80ZY24-200) proves that the system does not only guarantees high precision of speed and position, but also adapts the change of torque when it is changable continuously and protects DC motor effectively. So system is applicable to control the valve used in the petrochemical field production.