Load emulation technique for variable power factor and harmonic loads with energy recycling

Load emulation technique for variable power factor and harmonic loads with energy recycling

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The need for emulation of electrical load is often experienced in industrial design, development, and testing of electrical sources, especially in the case of renewable energy sources. The performance of standalone renewable energy systems is found to vary considerably with a change in load characteristics, especially with varying power factor (PF) and harmonics. Here a novel load emulation technique has been developed, using which variable PF and variable harmonic loads can be easily emulated and the energy drawn by the load can be recycled. In the proposed technique, the current drawn by the load is divided into in-phase, leading and lagging components. Each component is controlled individually. The in-phase power is then regenerated. The simulation and hardware results show exact variation in load characteristics as per the test requirements, which are difficult or impossible using passive loading and existing load emulation techniques with back to back converters. The proposed method is found to be more accurate, flexible and easier for emulation of low PF and high harmonic loads. A performance study is also conducted on a solar photovoltaic system using the developed model, substantiating the importance of this load emulation method.


    1. 1)
      • 1. Wang, J., Yang, L., Ma, Y., et al: ‘Static and dynamic power system load emulation in a converter-based reconfigurable power grid emulator’, IET Commun., 2012, 6, (5), pp. 125138.
    2. 2)
      • 2. Heredero-Peris, D., Jorge-Ques, F., Montesinos-Miracle, D., et al: ‘Resonant load emulator for distributed energy resources to test anti-islanding algorithms’. Int. Exhibition and Conf. for Power Electronics, Intelligent Motion, Renewable Energy and Energy Management, Nuremberg, Germany, 2016, pp. 18.
    3. 3)
      • 3. Elsayed, A., Ebrahim, A.F., Mohammed, H., et al: ‘Design and implementation of AC/DC active power load emulator’. SoutheastCon, Fort Lauderdale, FL, 2015, pp. 15.
    4. 4)
      • 4. Kesler, M., Ozdemir, E., Kisacikoglu, M.C., et al: ‘Power converter-based three-phase nonlinear load emulator for a hardware testbed system’, IEEE Trans. Power Electron., 2014, 29, (11), pp. 58065812.
    5. 5)
      • 5. Kanaan, H.Y., Caron, M., Al-Haddad, K.: ‘Design and implementation of a two-stage grid-connected high efficiency power load emulator’, IEEE Trans. Power Electron., 2014, 29, (8), pp. 39974006.
    6. 6)
      • 6. Kanaan, H.Y., Caron, M., Al-Haddad, K.: ‘Design, modeling, control and simulation of a two-stage grid-connected power load emulator’. IECON – 38th Annual Conf. on IEEE Industrial Electronics Society, 2012, pp. 37743779.
    7. 7)
      • 7. Primavera, S., Rella, G., Maddaleno, F., et al: ‘One-cycle controlled three-phase electronic load’, IET Power Electron., 2012, 5, (6), pp. 827832.
    8. 8)
      • 8. Smedley, K., Abramovitz, A., Maddaleno, F., et al: ‘One cycle controlled three-phase load emulator’. IEEE Applied Power Electronics Conf. and Exposition (APEC), 2011, pp. 20352039.
    9. 9)
      • 9. Rao, Y.S., Chandorkar, M.C.: ‘Real-time electrical load emulator using optimal feedback control technique’, IEEE Trans. Ind. Electron., 2010, 57, (4), pp. 12171225.
    10. 10)
      • 10. Wang, J., Ma, Y., Yang, L., et al: ‘Power converter-based three-phase induction motor load emulator’. IEEE Applied Power Electronics Conf. and Exposition (APEC), 2013, pp. 32703274.
    11. 11)
      • 11. Srinivasa Rao, Y., Chandorkar, M.: ‘Electrical load emulator for unbalanced loads and with power regeneration’. IEEE Int. Symp. on Industrial Electronics (ISIE), 2012, pp. 320327.
    12. 12)
      • 12. McGregor, I.: ‘The relationship between simulation and emulation’. Proc. Winter Simulation Conf., December 2002, no. 2, pp. 16831688.
    13. 13)
      • 13. Slater, H.J., Atkinson, D.J., Jack, A.G.: ‘Real-time emulation for power equipment development. Part 2: the virtual machine’, IEE Proc. Electr. Power Appl., 1998, 145, (3), pp. 153158.
    14. 14)
      • 14. Atkinson, D.J., Jack, A.G., Slater, H.J.: ‘The virtual machine [power electronic conversion equipment testing]’. IEE Colloquium on Vector Control, February 1998, pp. 7/17/6.
    15. 15)
      • 15. IEC 61683-1-1: ‘Photovoltaic systems – power conditioners – procedure for measuring efficiency’, edition 1, 1999.
    16. 16)
      • 16. Vijay, V., Giridhar Kini, P., Viswanatha, C., et al: ‘Load emulators for testing of power supplies’, J. CPRI, 2013, 9, (3), pp. 415422.
    17. 17)
      • 17. Jeon, J.-H., Kim, J.-Y., Kim, H.-M., et al: ‘Development of hardware in-the-loop simulation system for testing operation and control functions of microgrid’, IEEE Trans. Power Electron., 2010, 25, (12), pp. 29192929.
    18. 18)
      • 18. Vijay, V., Viswanatha, C., Giridhar Kini, P., et al: ‘Regenerative load emulator with battery charging for evaluation of energy management in microgrid with distributed renewable sources’. IEEE Modern Electric Power System Conf., Poland, July 2015.
    19. 19)
      • 19. Mohan, N., Undeland, T.M., Robbins, W.P.: ‘Power electronics: converters, applications, and design’ (Wiley, Hoboken, New Jersey, USA, 2002, 3rd edn.).
    20. 20)
      • 20. ST Microelectronics: ‘UM0877, 1.4 kW digital power factor corrector based on the STM32F103ZE’, (ST Microelectronics, 2010), pp. 162, Document available online at
    21. 21)
      • 21. Vijay, V., Viswanatha, C., Giridhar Kini, P., et al: ‘Novel load emulation technique for performance evaluation of isolated solar PV system under varying load conditions’, J. CPRI Special Issue, 2016, 12, (1), pp. 133138.

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