Improving the stability of the battery emulator — Pulsed current load interface in a Power Hardware-in-the-Loop Simulation

Replacing a battery pack with a battery emulator (BE) in a Power Hardware-in-the-Loop Simulation (HILS) setup facilitates the testing of new prototype hardware but stability and high fidelity are not a priori ensured. Due to the large output capacitance that devices implementing BEs usually have, their dynamic response differs compared to a real battery which operates like a voltage source with a series resistance. This problem becomes particularly intense when the hardware under test (HUT) also has a large input capacitance. The intuitive solution proposed is to connect a series resistor between the BE and the HUT to replicate the battery series resistance. This paper describes the conditions that this resistor needs to follow in order to ensure stability. It is also shown that the limited bandwidth of the power device used to implement the BE is possible to bring the emulation into stability even if those conditions are violated. Finally, examples are given on how a low sampling frequency in the feedback loop cause oscillations. Simulations and experiments are used to demonstrate all the findings.

[1]  Enrico Santi,et al.  Stability and accuracy considerations in the design and implementation of a kilowatt-scale DC power hardware-in-the-loop platform , 2014, 2014 IEEE Energy Conversion Congress and Exposition (ECCE).

[2]  C. S. Edrington,et al.  Investigation of HIL interfaces in nonlinear load studies , 2012, 2012 North American Power Symposium (NAPS).

[3]  F. V. P. Robinson,et al.  Analysis of Battery Lifetime Extension in a Small-Scale Wind-Energy System Using Supercapacitors , 2013, IEEE Transactions on Energy Conversion.

[4]  Felix Lehfuss,et al.  Power hardware-in-the-loop implementation and verification of a real time capable battery model , 2014, 2014 IEEE 23rd International Symposium on Industrial Electronics (ISIE).

[5]  Alexander Viehweider,et al.  Interface and Stability Issues for SISO and MIMO Power Hardware in the Loop Simulation of Distribution Networks with Photovoltaic Generation , 2012 .

[6]  M. Steurer,et al.  An Effective Method for Evaluating the Accuracy of Power Hardware-in-the-Loop Simulations , 2008, IEEE Transactions on Industry Applications.

[7]  Stefan Jakubek,et al.  Battery Emulation for Power-HIL Using Local Model Networks and Robust Impedance Control , 2014, IEEE Transactions on Industrial Electronics.

[8]  Phil H. Mellor,et al.  Performance comparison of diffusion, circuit-based and kinetic battery models , 2015, 2015 IEEE Energy Conversion Congress and Exposition (ECCE).

[9]  Salvatore D'Arco,et al.  Comparing the Dynamic Performances of Power Hardware-in-the-Loop Interfaces , 2010, IEEE Transactions on Industrial Electronics.

[10]  David Drury,et al.  Investigation and validation of methods to implement a two-quadrant battery emulator for power Hardware-in-the-Loop Simulation , 2016, IECON 2016 - 42nd Annual Conference of the IEEE Industrial Electronics Society.

[11]  C. S. Edrington,et al.  Improved power hardware in the loop interface methods via impedance matching , 2013, 2013 IEEE Electric Ship Technologies Symposium (ESTS).