Loss minimization of induction machines during torque transients

Abstract

This article presents a new design of an energy optimization approach to induction motor drives. The proposed control strategy is based on a designed cost function given as a weighting sum of power and energy models and subjected to the dynamic of a low-order current-fed induction motor model, which considers only the dynamics of the rotor flux and the mechanical equation as constraints to the problem. Such a strategy uses the concept of off-line optimal closed-loop control. Considering the case of a random desired torque, the resolution with suboptimal conditions allows a time-varying rotor flux that converges to the optimal solution and minimizes energy in a dynamic operation. This solution is presented in an analytical form and is dedicated to optimizing a transient regime characterized by a random load torque. This command law will become invariant with respect to time and will asymptotically tend to a stationary optimal solution. Aiming to check the validity of the proposed algorithm, a comparison study is conducted between rotor-field-oriented control operating with a suboptimal rotor flux and rated constant-flux control. The simulation and experimental results obtained for a 1.5-kW laboratory induction motor demonstrate the effectiveness of the proposed strategy.

Keywords

Induction machines loss minimization torque transients nonlinear control optimal control

Get full access to this article

View all access options for this article.

References

Tobnaghi

Alirezaloo

Gheydi

, et al. Induction motor drive design based on efficiency optimization and drive loss minimization. In: Proceedings of the 10th international symposium on advanced topics in electrical engineering, Bucharest, 23–25 March 2017. New York: IEEE.

Di Piazza

Luna

Pucci

Electrical loss minimization technique for wind generators based on a comprehensive dynamic modelling of induction machines. IEEE T Ind Appl 2017; 53(4): 3696–3706.

Uddin

Nam

SW.

Development of a nonlinear and model-based online loss minimization control of an IM drive. IEEE T Energy Conver 2008; 23(4): 1015–1024.

Gennady

Maxim

Igor

. Energy—efficient control of double inverter-fed induction motor. In: Proceedings of the 15th international conference on electrical machines, drive and power systems (ELMA), Sofia, 1–3 June 2017. New York: IEEE.

Kumar

Chauhan

Shrivastava

. Performance analysis of induction motor drive with optimal rotor flux for energy efficient operation. In: Proceedings of the IEEE international conference on advanced communication control and computing technologies (ICACCCT), Ramanathapuram, India, 8–10 May 2014. New York: IEEE.

Abrahamsen

Blaabjerg

Pederson

, et al. On the energy optimized control of standard and high-efficiency induction motors in CT and HVAC applications. IEEE T Ind Appl 1998; 34(4): 822–831.

Weng

Hsu

YY.

Sliding mode regulator for maximum power tracking and copper loss minimisation of a doubly fed induction generator. IET Renew Power Gen 2015; 9(4): 297–305.

Ashari

Pislaru

Ball

. Energy optimisation of sensorless induction motor drives using a novel robust-adaptive flux simulator. In: Proceedings of the 2012 second international electric drives production conference (EDPC), Nuremberg, 15–18 October 2012, pp.1–8. New York: IEEE.

Hamid

RHA

Amin

AMA

Ahmed

, et al. New technique for maximum efficiency and minimum operating cost of induction motors based on particle swarm optimization (PSO). In: Proceedings of the 2006 eleventh international middle east power systems conference, Minya, Egypt, 19–21 December 2006, vol. 2, pp.416–420. New York: IEEE.

10.

Wang

Ling

. Improved efficiency optimization for vector controlled induction motor. In: Proceedings of the Asia-Pacific power and energy engineering conference (APPEEC’2009), Wuhan, China, 27–31 March 2009, pp.1–4. New York: IEEE.

11.

Canudas de Wit

Ramirez

. Optimal torque control for current-fed induction motors. IEEE T Automat Contr 1999; 44(5): 1084–1089.

12.

Plathottam

Salehfar

Transient loss minimization in induction machine drives using optimal control theory. In: Proceedings of the 2015 IEEE international electric machines & drives conference (IEMDC), Coeur d’Alene, ID, 10–13 May 2015, pp.1774–1780. New York: IEEE.

13.

Khalil

. Chapter 9: stability of perturbed systems (Theorem 9.1). In: Khalil

(ed.) Nonlinear systems. Upper Saddle River, NJ: Prentice Hall, 1996, pp.340–345.

14.

Abdelati

Mimouni

MF.

Analytical solution of optimized energy consumption of induction motor operating in transient regime. Eur J Control 2011; 17(4): 397–411.

15.

Abdelati

Minimum-energy consumption of an induction motor operating in dynamic regime. J Electr Eng 2010; 10: 90–100.

16.

Geering

HP.

Optimal control with engineering applications. Berlin; Heidelberg: Springer-Verlag, 2007.

17.

Naidu

DS.

Optimal control systems. Boca Raton, FL: CRC Press LLC, 2003, pp.277–280.

18.

Polyanin

Zaitsev

VF.

Handbook of exact solutions for ordinary differential equations. Boca Raton, FL: CRC Press LLC, 1995.