Online Adaptation of Rotor Resistance based on Sliding Mode Observer with Backstepping Control of A Five-Phase Induction Motor Drives

Abstract

Multiphase electric drives have been developed due to numerous advantages offered by those machines when it compared with the conventional three-phase machines. Multiphase motor drives are considered for applications, where the reduction of power per phase for both motor and inverter and high reliability are required. High performance control techniques are developed for multi-phase drives. The performances of the high performance controller and flux observers may be degraded during the operation. Since the parameters of Induction Motor (IM) varies continuously due to temperature variation and heating. Thus it is significantly important that the value of rotor resistance is continuously observed online and adapted by the control algorithm in order to avoid detuning effects. The efficiency and performance of an induction motor drive system can be improved by online observation of the critical parameters, such as the rotor resistance and stator resistance. Among the parameters of IM, rotor resistance is a decisive one for flux estimation, and also the stator resistance becomes critical in the low-speed operation condition. This paper presents a new online estimation method for the rotor resistance of the IM for sliding mode observer. This method generally based on theories of variable structure and is useful in order to adjust online unknown parameters (load torque and rotor resistance). The presented non-linear compensator afford a voltage inputs on the articulation of stator current and rotor speed measurements, and engender an estimates for the unknown parameters simultaneously, the non-measurable state variables (rotor flux and derivatives of the stator current and voltage) that converge to the corresponding true values. Under the persistent excitation condition, the proposed method estimates the actual value of rotor resistance, which guarantees the exact estimation of the rotor flux. Non-linear Backstepping control and adaptive sliding mode observer of a five-phase induction motor drive is presented. The accuracy and validity of the method is verified by MATLAB simulation model.

dSPACE DS1104 Based Real Time Implementation of Sliding Mode Control of Induction Motor

“…Variable structure control (VSC) with sliding mode, or sliding-mode control (SMC), is one of the effective nonlinear robust control approaches, because it provides system dynamics with an invariance property to uncertainties once the system dynamics are controlled in the sliding mode [11], [12], [15], [16], [17], [18], [19], 20]. The first step of SMC design is to select a sliding surface that models the desired closedloop performance in state variable space.…”

“…Taking into account the equations of the induction motor defined in (11) and (12), the time derivative of sliding surface can be writing as follows:…”

MRAS-based Sensorless Speed Integral Backstepping Control for Induction Machine, using a Flux Backstepping Observer

“…The objective to design an integral backstepping control, allowing to ensure the tracking of rotor speed and rotor flux for the machine [20][21], we define the errors r ω e and r φ e respectively representing the error between the actual speed r ω and the reference speed r   and the error between the flux module dr  and its reference dr…”

Design of an Improved MPPT Control of DFIG Wind Turbine under Unbalanced Grid Voltage using a Flux Sliding Mode Observer

“…In this work, the wind turbine will be exploited at the maximum power operating point (MPPT) for various wind speeds by optimally controlling the speed of the shaft [1]. In contrast, regulating the rotor flux need the state vector of the controlled system.Thus, a good knowledge of the rotor flux is a necessity [2]- [3]- [4].Hence; the use of a physical sensor introduces a lot of problem in maintenance, quality of service, precision and cost. To overcome this difficulty, preceding works present the observer for flux estimation, then the speed is estimated from flux [5] - [6].Indeed; different models have been proposed for estimating rotor flux.…”