井下涡轮发电机系统特性分析与实验

为了详细了解无线随钻测量仪器中磁耦合器传递扭矩式井下涡轮发电机系统的工作特性,首先分析了其结构及工作原理,基于MATLAB的Simulink仿真环境,给出了井下涡轮发电机系统各组成部分的数学方程,建立了井下涡轮发电机系统的仿真模型。仿真了井下涡轮发电机系统空载和负载2种工作状态下的发电机转速、磁耦合器输出扭矩等各输出量的典型动态响应波形,分析了引起磁耦合器滑脱(失步)的2种情况(钻井液排量超过上限值或者发电机电磁扭矩与阻尼扭矩之和超过给定值)及其预防措施。空载时发电机整流输出电压随钻井液排量变化的实验数据与仿真结果基本吻合,验证了井下涡轮发电机系统仿真模型的正确性。井下涡轮发电机仿真模型为进一步分析磁耦合器传递扭矩式井下涡轮发电机系统的性能提供了很好的平台。 

Performance Analysis of Downhole Turbine Alternator System and Its Experimental Verification

To get a clear understanding of the operating performance of downhole turbine alternator system through magnetic coupling used in the measurement while drilling(MWD)instrument,its structure and operating principle were analyzed firstly,and then the mathematic equation of turbine generator was proposed,a simulation model of the entire system was built based on the simulation environment of Simulink in MATLAB.The simulation results gave the typical dynamic response waveforms of the output parameters such as RPM of alternator,output torque of magnetic coupling and so on in two operating modes(no-load on alternator and load on alternator)of the system,and two cases of asynchronous slip in magnetic coupling(mud flow rate exceeds the upper limit or the sum of electromagnetic torque and damping torque exceeds the rated value)and their prevention measures were analyzed.The experiment data change of rectified output DC voltage and mud flow rate in no-load on alternator coincided basically,which proved the correctness of the simulation model.The simulation model provides a good basis for further analyzing the downhole turbine generator system that through magnetic coupling the torque transmitted.