Research On The Strategy For Diesel Engine Torque Compensation System Based On PMSM

Diesel engine has been now widely used in drilling platform, while its torquecharacteristics is relatively soft, when faced with shocking torque load, prone tofall sharply or even stall. This paper proposes a method for the application of torquecompensation control system which uses diesel engine as while as permanentmagnet synchronous motor(PMSM), in the engine output shaft coaxial connector aPMSM which can afford short-time overload for compensation. This paper analyzesthe double-input torque compensation control system mathematical model and itstorque characteristics, as while as the control strategy based on a study of thecompensation PMSM.Firstly, a double-input torque compensation control system mathematicalmodel using diesel engine and AC motor is established, analysis the torquecharacteristics when the diesel engine has sudden torque load, A simulation modelof diesel engine is built to analysis the reasons for the speed drops, and layfoundation for the later chapters for developing torque compensation controlstrategy.Secondly, choose PMSM as the torque compensation control motor, establishits mathematical model and use the double closed-loop vector control method. Inorder to identify the torque and compensate the sudden torque, the paper presents amethod which contains fuzzy control theory and PI control theory. Analysis thecontrolling effects using different membership functions, and develop the fuzzycontrol rules based on Mamdini fuzzy reasoning method.Thirdly, considering the system application environments, propose a methodusing sensor-less control technology. Study a rotor position estimation methodbased on sliding mode observer(SMO), make a construction of sliding modeobserver in a two-phase motor stationary coordinate system, and estimate the angleusing direct calculation and estimation methods applied to study the PLL. Furtheradd counter electromotive force observer to the SMO, and then by selectingappropriate adaptive law get the rotor position and speed signals using modelreference adaptive system(MRAS).Finally, build the experiment platform of torque compensation control systemaround the control chip DSP TMS320F2812, and then use a1kW SPMSM to test.Verify that the application of fuzzy PI controller can quickly identify the torque andbe able to compensate the sudden torque load of diesel engines on the spindle，aswhile as achieve a flexible exit; the estimation method combining with extendedSMO and MRAS has higher estimation accuracy, which can be applied in practical control system.