EV Motor Back-EMF Testing & Energy Feedback with Hangyu Bi-directional Supplies

Direct Answer & Executive Summary: EV Motor Bench Testing: Simulated back-EMF feedback loads during regenerative motor deceleration sweeps, using a high-power bi-directional Hangyu supply and a Suita precision power analyzer.

Last updated: 2026-07-08

Industry Focus

Electric Vehicle (EV) - Powertrain & Traction Motor Engineering.

Application Scenario

Simulating back-electromotive force (Back-EMF) feed-back voltage spikes and current sweeps during EV motor deceleration tests.

Challenge Details

During regenerative braking sweeps, the traction motor acts as a generator, pushing energy back onto the DC bus line. High-power deceleration steps can generate back-EMF spikes exceeding 800 V. Standard unidirectional DC supplies cannot sink reverse current, which causes the bus voltage to rise, triggering Over-Voltage protection (OVP) locks or damaging supply output capacitors.

Implementation Path

  1. Regenerative DC Sink: Installed a high-power bi-directional dc power supply (Hangyu HY-TC Series) capable of seamlessly transition from sourcing current to sinking regenerative energy, feeding 95% of the absorbed energy back to the grid.
  2. Precision Power Analysis: Connected a multi-channel Suita power analyzer (SPT series) to measure the phase angles, power efficiency, and harmonic distortion across the motor inverter terminals.
  3. Low-Inductance Busbar: Connected the DC supply to the inverter using custom low-inductance shielded copper busbars to suppress transient voltage ringing during high slew-rate transitions.

Case Outcome

*Note: Customer name omitted for commercial confidentiality. Validated on an EV powertrain test bed.* Safely managed 45kW of feedback energy during deceleration runs. The Suita analyzer logged full efficiency mapping with a basic power accuracy of \pm 0.05\%, enabling optimization of motor control algorithms.