Grid-Scale Battery Energy Storage Systems (BESS) Successfully Execute Full Substation Black-Start Trials

Multi-hundred megawatt BESS installations equipped with grid-forming silicon-carbide inverters successfully energize 400 kV step-up transformers and restart ...

Grid-Scale Battery Energy Storage Systems (BESS) Successfully Execute Full Substation Black-Start Trials

Multi-hundred megawatt BESS installations equipped with grid-forming silicon-carbide inverters successfully energize 400 kV step-up transformers and restart gas turbine units without auxiliary diesel generators.

Eliminating Heavy Fuel Reliance in Black-Start Sequences

A consortium of European and Australian grid operators has completed field black-start trials demonstrating that grid-scale lithium-iron-phosphate (LFP) BESS facilities can autonomously energize unpowered 400 kV transmission substations.

Traditionally, restoration of a collapsed power system relies on heavy diesel generators or hydro plants to provide initial excitation power to energize massive step-up power transformers and thermal auxiliaries.

Managing Severe Inrush Currents with Controlled Soft-Start Switching

The primary engineering hurdle in transformer energization is handling inrush currents, which can peak at 8 to 10 times nominal rated current, driving magnetic cores deep into saturation and triggering protective relay trips.

Using high-speed inverter software with synchronized point-on-wave switching and soft-start voltage ramp profiles, the BESS gradually energized a 300 MVA 400/110 kV autotransformer with zero transient overvoltage or frequency deviation.