Page 34 - TTG-Taiwan Transportation Equipment Guide (TTG) 2026-04 Edition

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Technology News

High-Power EV Validation Shifts to igh-Power EV Validation Shifts to
H

Real-Load Conditions-Load Conditions
Real

By Sherry Chen
As 800V architectures and 500A fast-charging related frequencies overlap with the fundamental,
systems gain traction, electric vehicle (EV) power the source of power-quality degradation becomes
modules face increasingly demanding high-current diffi cult to isolate. As high-frequency switching and
validation requirements. Traditional low-load high-power operation become standard, frequency-
measurements no longer capture the nonlinear domain analysis is increasingly important.
magnetic and thermal behavior that arises
under high-frequency, high-power operation. As To address this need, newer instruments
components approach saturation, simplifi ed models are adopting high-pass and band-pass filtering
often underestimate core losses, eddy currents, and combined with discrete Fourier transform (DFT)
heat generation, reducing effi ciency and increasing analysis. The MICROTEST 7140 power analyzer,
the risk of failure. Validation is therefore shifting for example, uses high-speed sampling and high-
back to measurement under actual operating order harmonic analysis to separate spectral
current. components. It enables engineers to identify
filtering deficiencies early in the development and
On-board chargers (OBCs), DC-DC converters, production process, thereby improving the quality
and power factor correction (PFC) stages continue and reliability of AC-DC modules.
to evolve toward higher power density and smaller
form factors. Magnetic components in these Within EV power architectures, coupled
designs must withstand higher DC bias and AC inductors are widely used in OBC and DC-DC
ripple currents. As inductive cores enter nonlinear stages to reduce phase ripple and improve transient
regions, inductance falls sharply, increasing ripple response. Under high-power conditions, however,
and destabilizing control loops, which are outcomes the coupling coefficient (k) varies with DC bias.
that degrade effi ciency and reliability. Measurements made without a load therefore
fail to represent in-system behaviour. Some test
As EV power systems transition towards equipment suppliers are integrating DC-bias k-value
megawatt-class operation, the assumption of measurement into structured validation workflows.
"higher voltage, lower current" is no longer suffi cient MICROTEST's DC Bias Test System (6632 +
for validation. Accurate assessment of magnetic 6243H), for instance, enables stable k-measurement
behavior and component reliability under real load across DC-bias levels, allowing engineers to
conditions has therefore become essential. Under quantify magnetic performance in nonlinear regions
these conditions, DC bias testing is emerging as a and enhance the stability of multiphase buck, DC-
key method for high-power magnetic verification. DC, and on-board charging systems.
High-current inductance scanning enables
engineers to reconstruct the effective behavior of Looking ahead, the expansion of EV charging
inductive components under nonlinear operating infrastructure, high-power motors, and high-
conditions, supporting more reliable design frequency three-phase power systems, together
optimization. with tightening IEC and ISO vehicle standards,
will increase demand for verification of harness
Measurement challenges also persist in AC-DC resistance, dielectric withstand, and insulation
power modules. Engineers have long struggled to integrity. Validation platforms capable of high-
separate low-frequency ripple from high-frequency current, high-frequency, and high-voltage testing
switching noise in time-domain waveforms. Most are, therefore, becoming a key technical criterion
conventional power analyzers rely mainly on low- in selecting partners across the global EV supply
pass fi ltering; when switching harmonics and PWM- chain.