Electro-Thermal Model-Based Design of Bidirectional On-Board Chargers in Hybrid and Full Electric Vehicles

Abstract

In this paper, a model-based approach for the design of a bidirectional onboard charger (OBC) device for modern hybrid and fully electrified vehicles is proposed. The main objective and contribution of our study is to incorporate in the same simulation environment both modelling of electrical and thermal behaviour of switching devices. This is because most (if not all) of the studies in the literature present analyses of thermal behaviour based on the use of FEM (Finite Element Method) SWs, which in fact require the definition of complicated models based on partial derivative equations. The simulation of such accurate models is computationally expensive and, therefore, cannot be incorporated into the same virtual environment in which the circuit equations are solved. This requires long waiting times and also means that electrical and thermal models do not interact with each other, limiting the completeness of the analysis in the design phase. As a case study, we take as reference the architecture of a modular bidirectional single-phase OBC, consisting of a Totem Pole-type AC/DC converter with Power Factor Correction (PFC) followed by a Dual Active Bridge (DAB) type DC/DC converter. Specifically, we consider a 7 kW OBC, for which its modules consist of switching devices made with modern 900 V GaN (Gallium Nitrade) and 1200 V SiC (Silicon Carbide) technologies, to achieve maximum performance and efficiency. We present a procedure for sizing and selecting electronic devices based on the analysis of behaviour through circuit models of the Totem Pole PFC and DAB converter in order to perform validation by using simulations that are as realistic as possible. The developed models are tested under various operating conditions of practical interest in order to validate the robustness of the implemented control algorithms under varying operating conditions. The validation of the models and control loops is also enhanced by an exhaustive robustness analysis of the parametric variations of the model with respect to the nominal case. All simulations obtained respect the operating limits of the selected devices and components, for which its characteristics are reported in data sheets both in terms of electrical and thermal behaviour.

Real‐time electro‐thermal modelling and predictive control design of resonant power converter in full electric vehicle applications

“…Through the MBD approach, designers can comprehensively verify both the design of systems and devices, and their interaction, enabling the complete verification of control and monitoring algorithms by integrating these logic directly on the target processors and making them interact with the rest of the system (or the virtual version of the process). This reduces the design time of both hardware and software, as well as the validation time, and can reduce the stress on the components that do not need to be brought to operational limits for tests that can be performed using a mathematical model [1][2][3][4][5][6][7][8].…”

Advanced Permanent Magnet Machines and Drives

“…The most commonly used technique is that of forced oscillations, often accompanied by the classic Ziegler-Nichols table [43][44][45][46][47][48]. Due to the ease of development and integration on an embedded platform, it is also one of the most widely used control techniques in power and control electronics in general [49][50][51], not only in electrical drives.…”

Performance Evaluation of Bidirectional SEPIC-ZETA DC-DC Converter with Different Ambient Temperature

“…In [11] proposed to employ a model-based approach to create modern hybrid and fully powered automobiles with a bidirectional onboard charger (OBC) device. The research's major purpose and contribution is to incorporate both electrical and thermal modeling of switching devices in the same simulation environment.…”