比例导引末导时间的等效时间常数估算法

提出了将高阶比例导引制导系统用一阶等效环节来近似,并通过一阶等效时间常数快速估算系统末导时间的方法。高阶比例导引制导回路的末导时间与系统阶数无关,仅与比例导引系数有关,因此当系统存在多个滞后环节时,可用一个一阶等效环节来近似。其等效时间常数为各一阶滞后环节时间常数之和,对于二阶滞后环节,当阻尼大于0.6时,其等效时间常数可取为二阶系统中一次项系数。不同的比例导引系数下,脱靶量归零的无量纲时间是一定的,即等效时间常数与末导时间呈线性关系,据此可以估算系统的末导时间。此方法可以推广到对任意阶比例导引制导系统的末导时间的估算。

Estimation on Engagement Time of Proportional Navigation Guidance System using Approximate Time Constant

By representing the High-order PN guidance system with a single-lag guidance system, a method for the estimation of the engagement time was put forward according to the approximate time constant. The engagement time of high-order PN guidance system is related with PN coefficient regardless of system order. When the system has multi-lag, the high-order system can be represented by an equivalent single-lag. The Approximate time constant of the system is the sum of all the time constants of the one-order lags and for the biquadratic lag system, and the approximate time constant is the first-order coefficient of the binomial. Since the approximate time constant is linear with the engagement time for different PN coefficient, it can be estimated. The method can be extended to the estimation of the engagement time for random order PN guidance system.