绘制开环系统Nyquist曲线的研究

Research for Plotting Diagram of Open-loop Systems

从两个方面对如何更好地绘制开环系统曲线进行了研究：（１）对它的计算方式进行有效的改进，推出实、虚频特性计算通式，它方便于手算，更方便于计算机编程运算；（２）针对快速确定曲线有关形状给出了２个判据，即起始渐近线判据和实、虚频交点判据．

The method of effective plotting diagram of open-loop systems was studied in two aspects. Fir- stly, his calculus was efficaciously improved: the common formula of real and imaginary frequency response was advanced that is convenient for manual computation and more convenient for compute programming.Sec- ondly, two criterions are posed for use of quick confirming the forms of diagram: they are the criterion of orig- inal asymptote and cross-point on real and imaginary axes.