Power electronics switching applications are essential for energy management and conversion in automotive electric vehicles (EVs). This paper focuses on DC-DC converters, particularly the integration of 48V DC-DC converters in modern automotive systems. These converters are crucial for efficient power delivery to auxiliary systems such as infotainment, lighting, safety electronics, and thermal management units. In mild hybrid electric vehicles (MHEVs), 48V systems support advanced features like regenerative braking, electric turbocharging, and start-stop functionality.
To ensure the reliability, safety, and performance of these converters, Hardware-in-the-Loop (HIL) testing has emerged as a powerful validation technique. HIL enables real-time simulation of the converter’s electrical environment and load conditions, allowing comprehensive testing of the control system without high-level voltage, significantly reducing development time, cost, and risk.
The methodology involves utilizing HIL testing to simulate the electrical environment and load conditions of 48V DC-DC converters in real-time. Various control algorithms, such as Voltage Mode Control, Current Mode Control, Digital PID, and Model Predictive Control (MPC), are employed to ensure voltage regulation, load response, and system stability under dynamic operating conditions. Key parameters simulated using HIL for software closed-loop operation include output voltage and current regulation, efficiency and power loss, Total Harmonic Distortion (THD), switching frequency behavior, closed-loop stability, dynamic response, power quality, ripple, diagnostic and fault-handling capabilities by adhering to ISO26262 safety standards.
By simulating various conditions, potential software issues dependent on hardware can be identified and addressed early in the development cycle, ensuring seamless integration of hardware and software components. The advantages of HIL testing include safe and repeatable fault injection, real-time performance analysis, early-stage software validation, and the ability to simulate complex load profiles and environmental conditions. As automotive systems become more electrified and software-driven, HIL testing is indispensable for accelerating innovation while ensuring compliance with safety and performance standards.