For the purpose of solving problems of the pump s high power consumption and serious resource waste in the water treatment system,an improvement scheme for the internal feedback chopper speed-control based on DSP(digital signal processor) closed-loop adjustment was put forward.

An internal feedback cascade speed control electromotor is formed by inserting a set of regulating winding into the same slot with the original stator.

This paper introduces the requirement of the boiler s blower fan running by speed adjustment for energy saving ,and the rules of choosing the way of speed adjustment, and the principle of the internal-feedback serial speed adjustment in the coal gas power plant of the iron and steel industry in detail, and compares with the other way of speed adjustment comprehensively.

This study aims to resolve some problems concerning the effects of content feedback and form feedback, hoping to improve the teaching and learning of foreign language writing in China.