钻井液连续波信号发生器控制方法

为了利用往复主阀产生钻井液连续波，从而实现井下信息高效、快速传递，研究了往复式钻井液连续波信号发生器的控制方法。在选择斜面凸轮作为控制机构的基础上，优选了普通无刷直流电动机并确定了改变电枢电压的调速方法，建立了往复主阀产生钻井液连续波时的电动机转速及负载转矩计算模型。经过算例分析，得到了能够产生正弦钻井液连续波的电动机转速、负载转矩和电枢电压随时间的变化规律:在半个周期内，电动机转速非线性减小，电动机负载转矩非线性增加，电动机最大负载转矩为0.46 N·m，电枢电压呈现先减小后增大的趋势。研究结果表明，改变电枢电压的调速方法是可行的，对连续波调频可以实现对井下信息的传输，提出的钻井液连续波信号发生器控制方法可以为井下信号发生装置的设计及现场应用提供参考。 

Research on the Control Methods of a Drilling Fluid Continuous Wave Signal Generator

In order to control the drilling fluid continuous waves generated by the reciprocating main valve,and achieve the efficient and rapid transmission of downhole information,the control methods of reciprocal continuous wave generator were studied.While selecting the beveled cam as the control actuator,the motor was selected and optimized,and the speed control method of changing armature voltage was determined.Then the calculation model of the motor speed and load torque when the reciprocating main valve generated the continuous wave of drilling fluid was established.After making the calculation,the motor speed that were capable of generating a continuous sinusoidal wave,and the variation rules of load torque and armature voltage along with time were obtained.In the half cycle,the motor rotary speed decreased nonlinearly,while the motor torque increased nonlinearly,where the maximum load of motor was 0.46 N·m and the armature voltage tended to decrease first and then increase.The research results showed that the speed control method of changing the armature voltage was feasible,and the frequency modulation of continuous wave could achieve the transmission of downhole information.The proposed control method for drilling fluid continuous wave signal generator could provide reference and serve as a model for design and field applications of the downhole signal generator.