Abstract
The direct type governer used for the speed control of Diesel Engine, has a dynamical unstable property. This is a very interesting problem as a stability problem of dynamical system including self excited oscilation, and has been studied by Routh and other investigators ever since the invention of governer by Watt. The governer is sometimes used safely with no damping device. This is not explained by linear theory, and the reason of the fact is thought to be due to the effect of time lag and frictional resistance existing in the controlling system. The author analysed the stability of governer with constant time lag in the paper “Stability of Retarded Control” and got a conclusion that the time lag gives a stabilising effect to the system. This paper presents a theoretical consideration on the stability of governer with frictional registance without viscous damping. The conclusion is that, a certain amount of frictional registance is necessary for the stable action of the control system, and the critical amount of it is given in fig 9 and 10 in a standard hon dimensional form.
