Measurement while drilling in deepwater drilling engineering can monitor pressure data underground in real time. Based on these pressure data, the operator can adjust the density of drilling fluid and wellbore orientation in order to improve the efficiency of drilling. At present, there is no real formation pressure-while-drilling with independent intellectual property at home which have be developed yet. Based on the current situation in this area, and combined with the national 11th five-year key project of “supporting technology of large scale oil and gas field deepwater drilling and completion projects” sub-project “development of formation pressure while drilling measuring device”, we analysised the key technologies of power supply and control system in downhole tools, as well as designed a turbine generator power supply and brushless DC motor control system design to resolve the power and control problem. First, the research situation and key technologies development of underground power supply and control systems at home and abroad are presented. Then the research background and research purposes are introduced. Based on these above analysis, we selected downhole turbine generators power supply and motor control system design as the paper topic and main contents. Second, according to the characteristics of the turbine generator power system and the pros and cons analysis of different switching power supply control method，a voltage regulator module for turbine generator switching power supply is designed to provide a steady supply of DC voltage for downhole tools which meeting the environmental requirements of downhole control. Third, under the premise of explaining the basic control principle and speed control strategy of brushless DC, a DSP-based brushless DC motor control system is developmented. The motor control system uses fuzzy adaptive PID control algorithm. In Matlab/Simulink environment, the model of BLDC motor control system is established, whose simulation analysis results show that the control system owns a good steady-state output, a strong robustness and an excellent adaptive ability. Finally, in order to verify the function completeness and environments adaptability of downhole power supply and control systems, a series of experiments are designed in indoor simulation environment and CNOOC environmental laboratory. The experimental results show that the underground power supply and control systems we designed can provide a st...
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