波德图相频特性的研究

The Complete Technique of Painting of Bode Diagram Phase-frequency Curve

为了更完整地画出对数相频特性曲线 ,用公式扒导和举例印证两面三刀种方法在理论和实践上得出含有不稳定环节时开环系统对数相频特性曲线的画法 :第一步 ,画出除ω=0 + 以外的对数相频特性曲线 φ(ω) ;第二步 ,当 p 为偶数时 ,从lgω轴上往负相位方向补画辅助曲线 ,当 p为奇数时 ,从 φ(ω) =- 180 ° 线上开始补画辅助曲线 ;与 φ(ω) 连接起来 ,加上对数幅频特性曲线 。

For drawing the log phase-frequency characteristics curve more completely,Should consider the circumstance that imply ther unsteady link.With two kinds of methods of ther formula Deduce and the exampless corroborate,This text get the technique of painting of the open loop system log phase-frequency characteristics curve in theory and practicing when imply ther unsteady link.First step,draw the divide ω=0 +excluding of log phase-frequency characteristics curve φ(ω);The second step,when p is even integer,start repairing the painting toward negative phase direction repairing the painting assistance curve from the stalk of lgω.When p is odd integer,fromφ(ω)=-180 °,beginning repairs the painting assistance curve.Link with φ(ω)again.Plus the log magnitude-frequency characteristics curve,then the application logarithm frequency criterion judges the stability of the closed loop system completely.