Study on suppressing nonlinear chaos of electric submersible motor for identifying temperature

In order to decrease negative effect and increase identification the precision of DC Injection Method(DIM) for identifying temperature of Electric Submersible Motor (ESM), we focus on the need for suppressing nonlinear chaos of electromagnetic torque of ESM. Based on analyzing qualitative relationship of electromagnetic torque to the stator current of ESM, the oscillation of instant torque and surge current of the stator induced by DIM is studied. Based on dynamics analysis the Wishout-filter state feedback control method is used to suppress the chaotic oscillation of electromagnetic torque of ESM. The design rules of series impedance between power system and the stator of ESM which influence on surge current of the stator is given by proposed method. Experiment results of 12 kW ESM shows the relative error of identification temperature of the stator of ESM reaches to 4.0%. It denotes the proposed method can provides theoretical and engineering basis for identifying the temperature of higher power AC motor by employing a newly developed DIM to suppressing corresponding negative effect.