Research Of Speed Measurement Algoruthm Based On FPGA And System Control For Servo Motor

Fast response and high precision sensors are key technologies in servocontrol system. For servo motor control, speed measurement accuracydirectly influences its stability and precision. Generally, higher precisionencoder is needed in order to get higher accuracy of speed measurement,but quite costly. This paper works on researching a speed measurementalgorithm that can make full use of the limited messages in low preciseencoder to get motor speed as precisely as the former one, at the same time,it considers the way to re-optimize system’s performance, according to thecharacter of speed measurement module.It is shown that the least square estimation method not only is easy torealize, but also possesses high speed measurement performance. Firstly,through experiments and frequency character analysis, a improved leastsquare algorithm is proposed, which is proved to have better performance;Secondly, factors that can influence its actual performance are pointed outand solved; Thirdly, necessity and feasibility are discussed of realizing it inFPGA; At last, the way to optimize system’s performance is introduced.Simulation results and motor experiments show that the proposedspeed measurement method can not only have high speed measurementaccuracy under low precision encode, but also is more useful in improvingsystem control character, compared with the traditional MF method.