Research And Design Of High-Power DC Motor Speed Control System

High-power DC motor is widely used on the offshore oil platform,because of its high varied speed quality and its higher reliability. It consists of strong power section and weak electronic plant. The weak electronic plant is used to get the signal that system needed, such as speed, armature current, motor temperature and thyristor temperature etc. Based on these signals, the weak electronic plant give control signals to the strong power section. Strong power section act according to the signals and change the speed of the DC motor, to satisfied the requirement of the working situation.With rapid growth of the economic and industry,oil consumption of China increased to 350 million tons, China becoming the world's second largest oil consumer country in 2007.According to preliminary calculations, Chinese oil and gas resources in ocean about 351 to more than 404 billion tons of equivalent oil, about 47 billion steres,which is nine times of the summation of Chinese oil and gas reserves in land and ocean,it is about 50.98 billion steres,in 2002.So exploration and development is great potential.In order to ensure the smooth development of Chinese economic and domestic stability, the need to intensify efforts to develop offshore oil exploration; on the other hand ,we have to speed up the offshore oil industry and technology of China-made equipment.High-power DC motor speed control system is the electric power core part of offshore oil drilling rig.Based on analyzing the load characteristics of the draw works,rotory table and mud pump, in allusion to the basic requirements of speed regulate system for offshore electric drilling rig, researching and design high-power DC motor speed regulate system used by the offshore oil platform.This article is also emphases on the design of a detailed explanation,including reliable trigger and protection of SCR,the design of system power supply,detection circuit of current signal,detection circuit of voltage signal,the regulator circuit and trigger circuit. And made a case for various kinds of interference by the corresponding suppression measures.The study of subject in line with the requirements of the state's domestic offshore oil drilling industry,which is control automation, low-cost, high efficiency.It has a practical significance for upgrading electric drilling rig speed regulate system of built drilling platform,but also has a little of reference significance for the offshore oil industry and technology of independent research and China-made.