Although traditional PID regulators give consideration to both static and dynamic regulating quality of the system

but the PID parameteras affect each other and the setting of PID parameter is comparatively complicated

and sometimes it even can not ensure normal working of the regulatory system.For this

a kind of PID controlling algorithm based on PID algorithm

in which the integral is separated

has been adopted.In said controlling algorithm

the integral gain is corrected according to the absolute value changing direction of deviation in regulated quantity.The said controlling algorithm has been applied in the developing process of emulation software for unit control system in thermal power plants.Results show that the said controlling algorithm overcomes thoroughly the problem of overshoot caused by the integral

increasing greatly the stable range of regulator's parameter

simplifying the setting process of regulator's parameter.The said algorithm can be used for automatic control in practical industrial process.