井下直驱螺杆泵潜油伺服系统的设计

Design of servo system for direct-driven submersible progressing cavity pump

潜油螺杆泵采油系统中通常采用减速器减速,并应用变频技术实现开环控制,系统调速性能较差,效率较低,电能损耗大。针对此问题,提出将具有低速大转矩和调速范围宽等特性的交流伺服技术应用于潜油螺杆泵采油系统,分别设计了永磁同步潜油电机以及能适应井下恶劣环境的磁电式编码器与伺服控制器,并在控制程序中加入压力环,通过调整电机转速使系统工作特性与油井产能相匹配。系统井下试验表明该系统在井下工作良好,从而验证了可行性。

Generally reducer is adopted in the submersible progressing cavity pump system to reduce the speed,and converter technique is applied to achieve open-loop control,which causes worse speed governing performance,lower efficiency,bigger loss of electric energy of the system.Aiming at the aforementioned weak points,a new kind submersible progressing cavity pump system is proposed in it which applies AC servo technology with features of high torque at low speed and wide range of speed regulation.Permanent magnet synchronous submersible motors,servo controllers and special magnetoelectric encoders which suit severe environment of deep well are designed respectively.And a pressure loop is added to the control program which can adjust the motor speed according to the pressure signal in order to match oil well productivity and the performance of the system.The deep well test demonstrates that the servo system serves well under the well which is proven to be feasible.