Research Of Controller For Heave Compensation System Based On DSP

The controller of heave compensation was the key of ultra-deep drilling working.The heave compensation systems,at present,were controlled by the industrial personal computer.However,it takes a bigger volume and better working environment for industrial personal computer.In comparison with the industrial personal computer,the heave compensation controller based on DSP not only can take advantage of industrial personal computer,but also can improve the overall quality of heave compensation controller.In this paper,the TMS320F28335 DSP was chosen as the main control chip of the heave compensation controller,and the control system was built which PC was worked as the host computer and DSP controller worked as the slave computer,and cylinder heave compensation system and winch heave compensation system was set as the research objects.Finally,the controllers were tested by model experiments.The following are the main works of this paper:1.The control principle of cylinder heave compensation and winch heave compensation was analyzed,and the working condition of drilling platform was introduced.The cylinder and winch heave compensation model experiments platform were built.And the compensation targets were set.2.The feedforward controller and speed feedback controller were added in the PID controller in order to improve the quality of cylinder heave compensation.To improve the robustness for winch heave compensation system,fuzzy PID was used and feedforward controller was applied in winch heave compensation system.3.A multiple host computer software was designed,including the data saving,curve plot,different order output function and some other functions.The communication between the host computer and the slave computer was built by using the RS485 serial port.More than 1500 lines C language program and near 4000 lines of C++ program were texted for the two model experiment systems.Two completed model experimental control systems were built.4.The good quality of the cylinder heave compensation was proved on the cylinder heave compensation model platform.The deviation of sin wave simulation experiments was 1.8 mm,and 2.4mm deviation was got during the P-M wave simulation.The standard deviation of sin wave heave compensation was 0.51 mm,and the standard deviation of P-M heave compensation was 1.06 mm.Both of quality of the cylinder compensation was to be reliable and reasonable.Less than 8.98% fluctuation of load was controlled by using the winch heave compensation controller while using the six-degree-of-freedom platform to make the sin heave movement.The quality of the winch heave compensation controller was proved by experiment results.The controller can be applied for the cylinder and winch heave compensation system.