Research On Methods To Realize Low Ripple Output Of DC Power Supply

Technology of the rotary steering drilling system is the most representative and advanced one of the present drilling technologies. Accuracy measurements on the deviation angle and azimuth angle of the bit with attitude measurement equipment are the key problem for the rotary steering drilling system, which is the foundation for the precision control of the drilling trace. To achieve the method of improving the accuracy of the attitude measurement, the drilling tool is simulated with an inclinometer in experiments, in which attitude parameters are measured with the combination of high accuracy gyroscope and three axis accelerometer. Due to the weak outputs of the above two sensors, the ripples of the power supply have serious impacts on the measuring accuracy. Although the battery has the advantages of no ripple and satisfy the requirement of the experiments, its capacity limits the measuring time of the inclinometer. Design high accuracy, low ripple and high reliability power supply has become the primary question in investigations on the high accuracy measurement of attitude parameters.Considering the requirement of high stabile, long time working and anti-disturbance power supplies in the experiments of the attitude parameters measurement with the inclinometer, realization methods for low ripple power supplies are studied and the design of the power supply for the experimental device to simulate the attitude measurement equipment in the rotary steering drilling system is finished, which is based on ripple control technologies and basic theories of power electronic technology. Core elements of the designed power supply are the two batteries working at alternant charging and discharging states to increase their capacity. Linear voltage stabilizing circuit is adopted to reject the harmonics in switches. With above methods, low ripple in the output of the power supply can be obtained.Experimental verifications on the designed power supply are realized. Results indicate that almost no variation in the output of the power supply can be found in the switching process. More important, the designed power supply can provide a stable and low ripple output voltage in long-term operations. Compared with available power supplies, the designed one has the advantages of simple structure and low ripple. Results in the thesis are important for the improvement of the measuring accuracy for the inclinometer.