As electric vehicles (EVs) and hybrid electric vehicles (HEVs) continue to reshape the automotive landscape, the demand for advanced EV testing solutions has never been higher. Engineers and manufacturers require highly accurate, efficient, and flexible test equipment to validate next-generation powertrains. Bidirectional power supplies for EV and HEV testing have emerged as a cornerstone technology, enabling realistic simulation, energy recovery, and accelerated product development.
What Is a Bidirectional Power Supply?
A bidirectional power supply is a programmable power system that can both source and sink power. Unlike conventional unidirectional power supplies, bidirectional units operate in four quadrants, allowing seamless transitions between delivering power to a device under test and absorbing energy from it.
In EV and HEV test environments, bidirectional DC power supplies are commonly used to emulate high-voltage batteries, DC buses, fuel cells, and charging systems, while safely capturing regenerative energy and returning it to the grid or facility power system.
Why Bidirectional Power Supplies Are Critical for EV and HEV Testing
Modern EV and HEV powertrains are highly dynamic. During acceleration, systems draw significant current, while regenerative braking and inverter operation push energy back into the test system. Bidirectional power supplies enable realistic, closed-loop testing of these operating modes.
Key benefits include:
Accurate battery emulation for EV and HEV development, including voltage, current, SOC, and internal resistance modeling
Regenerative power absorption, eliminating the need for external load banks
Higher energy efficiency through power recovery, reducing operating costs, and heat dissipation
Improved test fidelity for validating power electronics, control software, and efficiency targets
Key EV and HEV Test Applications
Bidirectional power supplies play a vital role across the entire EV and HEV testing workflow—from early R&D to end-of-line production testing.
Battery and BMS Testing
Bidirectional DC power supplies are widely used for battery management system (BMS) testing, enabling engineers to simulate battery packs without the safety risks associated with physical batteries. This enables fault injection, charge/discharge cycling, and compliance testing under controlled conditions.
Inverter and Motor Drive Testing
During inverter and motor drive testing, regenerated energy must be safely and efficiently absorbed. Bidirectional power supplies provide precise control and fast transient response, making them ideal for EV inverter testing and motor controller validation.
Onboard Charger (OBC) and DC-DC Converter Testing
For onboard charger testing and DC-DC converter validation, bidirectional power supplies support both input and output power flow. This enables engineers to verify efficiency, thermal performance, and bidirectional operation under real-world conditions.
EV Charging and Vehicle-to-Grid (V2G) Testing
As vehicle-to-grid (V2G) and bidirectional charging technologies gain adoption, bidirectional power supplies are essential for simulating grid behavior and validating power flow between the vehicle and the electrical grid.
Key Features to Look For in Bidirectional Power Supplies
When selecting a bidirectional power supply for EV and HEV test systems, engineers should consider:
Wide voltage and current ranges for high-voltage EV batteries
Fast transient response for dynamic drive cycles
Four-quadrant operation for seamless sourcing and sinking
High power density to reduce lab space requirements
Advanced safety features, including isolation and fault protection
Automation and communication interfaces such as CAN, Ethernet, and SCPI for automated test setups
Accelerating EV and HEV Development
As electrification continues to advance, bidirectional power supplies for EV and HEV testing enable faster validation, safer testing, and more efficient energy use. By combining battery emulation, regenerative power handling, and automation readiness, these systems help manufacturers shorten development cycles, improve product quality, and meet evolving regulatory requirements.
Investing in the right bidirectional power supply is not just about test accuracy—it's about enabling the future of electric mobility.
