Аннотация:
This paper presents a nonlinear sliding mode control (SMC) scheme with a variable damping ratio for interior permanent
magnet synchronous motors (IPMSMs). First, a nonlinear sliding surface whose parameters change continuously with time is
designed. Actually, the proposed SMC has the ability to reduce the settling time without an overshoot by giving a low damping
ratio at the initial time and a high damping ratio as the output reaches the desired setpoint. At the same time, it enables a fast
convergence in finite time and eliminates the singularity problem with the upper bound of an uncertain term, which cannot be
measured in practice, by using a simple adaptation law. To improve the efficiency of a system in the constant torque region, the
control system incorporates the maximum torque per ampere (MTPA) algorithm. The stability of the nonlinear sliding surface is
guaranteed by Lyapunov stability theory. Moreover, a simple sliding mode observer is used to estimate the load torque and
system uncertainties. The effectiveness of the proposed nonlinear SMC scheme is verified using comparative experimental
results of the linear SMC scheme when the speed reference and load torque change under system uncertainties. From these
experimental results, the proposed nonlinear SMC method reveals a faster transient response, smaller steady-state speed error,
and less sensitivity to system uncertainties than the linear SMC method