Research On The Key Technology Of The All-Electric Subsea Control System

Subsea control system is one of the key systems to ensure the deepwater production facilities run with safety and high efficiency. Due to the importance of the subsea control system, there is extremely high requirement of its system and equipment reliability. Therefore,studying and mastering overall design of subsea control system, breaking the design and manufacture technology of some key equipment, and testing and verifying the product reliability all will have great promoting function for the improving of subsea control system technology. This subject is committed to developing a set of the new all-electric subsea control system and there are two parts: the all-electric subsea control module and the all-electric valve actuator. According to the subject requirements,the main works of this dissertation are shown as follows:First of all, based on the intensive study of its overall structure and working principle,the mechanical structure and electric control design of the all-electric subsea control system is completed, with combining the design target and performance requirements.Then,the research focuses on the key structure and technology with the basis of the completed overall scheme design of all-electric subsea control system: For the requirements of locking and docking technology of all-electric subsea control module, a new form of operating locking mechanism with ROV is designed, and its strength is checked; By ANSYS,simulation analysis on O-ring rubber sealing of subsea electronic module is completed for getting the law of the maximum contact stress, equivalent stress and shear stress with the sealing structure change, and optimizing the sealing structure size on the premise of performance requirements according to the O-ring failure criterion; Based on the intensive research on driving technology with low voltage high power, the overall scheme of hardware and software system used for permanent magnet synchronous motor drive is proposed;Insulation technology involved in power transmission technology is analyzed, the overall scheme of the power transmission system is proposed as well.Moreover, according to the design index and performance requirements, the conceptual design of all-electric valve actuator is completed. And on this basis, I compare advantages and disadvantages between the proportion distribution method, score distribution method,distribution method of considering the importance and complexity, and its reliability allocation design is to be finished by distribution method with considering importance and complexity. Meanwhile, for the compression spring, which is the key part, intensity-stress interference model is built and three aspects of static strength, fatigue strength, stability reliability are analyzed by turns. Comprehensively considering relationship between three reliabilities and applying the theory of Ditlevsen narrow bound, the comprehensive reliability of compression spring is obtained and verified its reliability prediction value.Finally, for all-electric valve actuator, the mathematical model is built and its corresponding simulation model is established in AMESim. By dynamic simulation analysis of all-electric valve actuator, in which the focus is on four aspects: driving with constant speed, driving with constant torque, whether there is reset spring, fail-safe function, it is verified that drive performance of the all-electric valve actuators meet the design requirements.