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This paper presents the analysis and validation of a real-time ac drive simulator. Real-time simulation has been used for over a decade in power systems engineering to test controllers thoroughly, efficiently, and safely. The development and testing of large ac drives could benefit from this type of simulation, but real-time power system simulators have modeling restrictions preventing stable and accurate simulation of isolated drives switching at high frequencies. These restrictions can be overcome by combining in a single model both the power converter and motor models. After discussing the salient issues related to the real-time simulation of ac drives, a prototype real-time simulator for drives is described. Its ability to accurately emulate the behavior of large drives is demonstrated through two case studies. A first case study demonstrates the feasibility of simulating a drive of typical complexity in real-time. The second case study demonstrates how the controller for a PWM VSI fed induction motor, switching at 4 kHz, is designed, implemented in a microcontroner and tested in real-time using a simulated inverter, motor and load. Comparisons against results obtained with another simulation tool, which uses extremely accurate variable-step integration algorithms, demonstrates the validity of our approach. Index Terms--AC motor drives, hardware-in-the-loop testing, real time simulation, state space methods.

This paper presents a generic electrothermal model for Li-ion battery. The model is developed with the objective to simplify the parameter identification procedure, while representing adequately the thermal effects on the battery performance. Most of the well-accepted electrothermal Li-ion battery models require in-depth and proprietary battery data or dedicated test environments for parameter identification. The dedicated test bench usually involves expensive thermal test chambers, calorimeters, and temperatures sensors, and challenges associated with their installations. This makes the electrical and thermal simulation of Li-ion batteries difficult to achieve. This paper proposes a generic electrothermal model with a simpler parameter identification process. The parameters identification process is solely based on datasheet discharge curves and simple experiments at room temperature. The model is validated experimentally using a 12 V 40 Ah LiFePO4 battery module. The performance of the model is tested with constant current discharges, constant current–constant voltage charges, as well as with a Simplified Federal Urban Driving Schedule dynamic driving cycle, at different operating temperatures. As expected, the simulation results show an error within $\pm$1% and $\pm$1.3% compared to experimental results, for both steady and dynamic states, respectively. [ABSTRACT FROM AUTHOR]

In this letter, the authors present an approach for designing discrete packaging of a bidirectional power switch used in matrix converter applications. The study is based on computing the magnetic field inside a specific resonant switching cell in order to incorporate low-voltage control circuits inside the compact space volume of the power module. The novelty of the proposed configuration is the creation of an oriented magnetic field area, which has very low impact on the low-level control signals of the power devices. Numerical analyses as well as experimental results are presented to demonstrate the validity of the proposed approach. [ABSTRACT FROM AUTHOR]