位置伺服系统量化效应引起的振荡问题

针对位置传感器量化非线性造成的位置伺服系统极限环振荡问题，研究了在量化非线性和死区非线性共同作用下系统趋于稳态时的特性。采用单回路多非线性系统的描述函数方法给出了振荡时力矩死区同位置传感器量化阶之间的关系，并求得了能使系统镇定的死区范围，提出了以伺服误差的方差作为评价指标的寻优判据，采用数值方法解得使系统镇定的最小死区。仿真结果表明，在量化非线性和所求得的最小死区共同作用下，原有位置伺服系统在稳态时可以避免振荡。

Oscillation caused by quantized feedback in position servo system

The steady state properties of the position servo system which is influenced by quantization nonlinearity and deadzone nonlinearity are studied in this paper.The describing function technique for multiple nonlinearities in a single-loop feedback system is used to get the relationship between the bound of deadzone and the quantum step,and the bound of deadzone for stabilizing the chattering is obtained.A criterion using the variance of the error in the stable state is proposed to achieve the minimum bound of deadzone.By numerical simulation,the oscillation is avoided in a servo system of electrical simulation table system which includes quantization nonlinearity and deadzone nonlinearity with the minimum bound.