Hamed GORGINPOUR, Behzad JANDAGHI, Mohammad Naser HASHEMNIA, Hashem ORAEE

Optimal reactive power ow in BDFMs for converter cost reduction and efficiency improvement

A brushless doubly fed machine is equipped with two decoupled windings on its stator, known as the power winding and the control winding. The power winding reactive power can be controlled by voltage amplitude fed by the machine-side converter to the control winding, affecting both the converter size and machine efficiency. This paper investigates different proposed scenarios for optimal reactive power ow targeted to minimize the converter cost and maximize the machine efficiency. Previously, the grid-side converter has not been used for reactive power compensation. However, in the present paper it is shown how the grid-side converter can be effectively used to reduce the converter cost by controlling the ow of reactive power. The optimal power winding reactive powers for minimizing the converter cost and for maximizing the output power are not the same. Then the priority of minimizing converter cost over maximizing machine output power has been justi ed.

PDF

___

[1] Wallace AK, Spee R, Lauw HK. The potential of brushless doubly-fed machines for adjustable speed drives. In: IEEE 1990 Pulp and Paper Industry Technical Conference; 18 June 1990; New York, NY, USA: IEEE. pp. 45-50.
[2] Brune C, Spee R, Wallace A. Experimental evaluation of a variable-speed, doubly-fed wind-power generation system. IEEE T Ind Appl 1994; 30: 648-655.
[3] Long T, Shao S, Abdi E, Malliband P, Mathekga ME, McMahon RA, Tavner PJ. Symmetrical low voltage ride- through of a 250 kW brushless DFIG. In: IET 2012 International Conference on Power Electronics, Machines and Drives; 27{29 March 2012; Bristol, UK: IET. pp. 1-6.
[4] Roberts PC. A study of brushless doubly-fed (induction) machines. PhD, University of Cambridge, Cambridge, UK, 2004.
[5] Tohidi S, Zolghadri, M, Oraee H, Tavner P, Abdi E, Logan T. Performance of the brushless doubly-fed machine under normal and fault conditions. IET Electr Power App 2012; 6: 621-627.
[6] Poza J, Oyarbide E, Sarasola I, Rodriguez M. Vector control design and experimental evaluation for the brushless doubly fed machine. IET Electr Power App 2009; 3: 247-256.
[7] Shao S, Abdi E, Barati F, McMahon R. Stator- ux-oriented vector control for brushless doubly fed induction generator. IEEE T Ind Electron 2009; 56: 4220-4228.
[8] Barati F, McMahon R, Shao S, Abdi E, Oraee H. Generalized vector control for brushless doubly fed machines with nested-loop rotor. IEEE T Ind Electron 2013; 60: 2477-2485.
[9] Shao S, Abdi E, McMahon R. Low-cost variable speed drive based on a brushless doubly-fed motor and a fractional unidirectional converter. IEEE T Ind Electron 2012; 59: 317-325.
[10] Carlson R, Voltolini H. Grid synchronization of brushless doubly fed asynchronous generators in wind power systems. In: IEEE 2008 International Conference on Industrial Electronics; October 2008; Montevideo, Uruguay: IEEE. pp. 2173-2177.
[11] Wang X, Roberts PC, McMahon RA. Studies of inverter ratings of BDFM adjustable speed drive or generator systems. In: IEEE 2005 International Conference on Power Electronics and Drives Systems; 16 January 2006; Kuala Lumpur, Malaysia: IEEE. pp. 337-342.
[12] Wang X, Roberts PC, McMahon RA. Optimisation of BDFM stator design using an equivalent circuit model and a search method. In: 3rd IET 2006 Power Electronics, Machines and Drives Conference; 4 April 2006; Dublin, Ireland: IET. pp. 606-610.
[13] Abdi E, Oraee A, Abdi S, McMahon RA. Design of the brushless DFIG for optimal inverter rating. In: IET 2014 International Conference on Power Electronics, Machines and Drives; 8{10 April 2014; Manchester, UK: IET. pp. 4-4.
[14] Carlson R, Voltolini H, Runcos F, Kuo-Peng P, Batistela NJ. Performance analysis with power factor compensation of a 75 kw brushless doubly fed induction generator prototype. In: IEEE 2007 International Electric Machines & Drives Conference; 3 May 2007; Antalya, Turkey: IEEE. pp. 1502-1507.
[15] Abbey C, Joos G. Optimal reactive power allocation in a wind powered doubly-fed induction generator. In: IEEE 2004 Power Engineering Society General Meeting; 10 June 2004; Denver, CO, USA: IEEE. pp. 1491-1495.
[16] Abbey C, Joos G. A systematic approach to design and operation of a doubly fed induction generator. Electr Pow Syst Res 2008; 78: 399-408.
[17] Aguglia D, Viarouge P, Wamkeue R, Cros J. Analytical determination of steady-state converter control laws for wind turbines equipped with doubly fed induction generators. IET Renew Power Gen 2008; 2: 16-25.
[18] Troncoso PE, Battaiotto PE, Mantz RJ. Active and reactive power control capability in wind generation based on BDFIG machine. In: Innovative Smart Grid Technologies Latin America; 5{7 October 2015; Montevideo, Uruguay: IEEE PES. pp. 546-551.
[19] Oraee A, Abdi E, McMahon RA. Converter rating optimisation for a brushless doubly fed induction generator. IET Renew Power Gen 2014; 9: 360-367.
[20] Oraee A, Abdi E, Abdi S, McMahon RA. A study of converter rating for Brushless DFIG wind turbines. In: IET 2007 Renewable Power Generation Conference; 9 September 2013; Beijing, China: IET. pp. 1-4.
[21] McMahon RA, Abdi E, Malliband PD, Shao S, Mathekga ME, Tavner PJ. Design and testing of a 250 kW medium- speed brushless DFIG. In: IET 2012 Power Electronics, Machines and Drives Conference; 27 March 2012; Bristol, UK: IET. pp. 1-6.
[22] Roberts PC, McMahon RA, Tavner PJ, Maciejowski JM, Flack TJ. Equivalent circuit for the brushless doubly fed machine (BDFM) including parameter estimation and experimental veri cation. IEE P-Elect Pow Appl 2005; 152: 933-942.
[23] McMahon RA, Roberts PC, Wang X, Tavner PJ. Performance of BDFM as generator and motor. IEE P-Elect Pow Appl 2006; 153: 289-299.
[24] Junchuan J, Weiguo L. Control characteristic of three-phase voltage-source PWM recti er. Electric Power Automa- tion Equipment 2010; 30: 63-65.