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Electric Vehicles

What is an Inverter?

Converts the battery's DC power into the AC power the motor actually uses.

INVERTER — TURNS DC INTO 3-PHASE ACHV BATTDC 400VDC inINVERTERpower transistors switchingMmotorChops DC into a precisely shaped 3-phase AC waveform — controls speed, torque and regen

Simplified animation — not to scale.

In plain English

The inverter is one of the most important EV components most people have never heard of. It sits between the high-voltage battery and the motor, and its job is to convert the battery's direct current (DC) into the alternating current (AC) the motor needs — and to control exactly how much, how fast, and in which direction.

A simple analogy

"Think of it like a translator and a throttle in one box. The battery only speaks "DC", the motor only speaks "AC", and the inverter translates between them while deciding how loudly to talk."

How it works

When you press the accelerator, the car's computer tells the inverter how much torque you want. The inverter then chops the DC from the battery into a precisely shaped three-phase AC waveform using fast power transistors (IGBTs or silicon-carbide MOSFETs). When you lift off, the process runs in reverse — AC from the motor is rectified back to DC and pushed into the battery as regen.

Signs of trouble

  • ⚠Sudden loss of power
  • ⚠"Drive system fault" warning
  • ⚠Burning electrical smell
  • ⚠Reduced regenerative braking
  • ⚠Coolant warning (inverters are liquid-cooled)
Rough UK cost

£1,500 – £5,400

Parts: £1,200 – £4,500
Labour: £300 – £900

Always get a written quote. Prices vary by car, region, and parts brand.

Heads up: Carautonomy is for general guidance only. If your car is showing warning lights or behaving oddly, get it looked at by a qualified mechanic.

Keep exploring

Alternator
The on-board power station that keeps your battery topped up.
EGR Valve
A small valve that recycles exhaust gas to reduce emissions.
Starter Motor
The muscle that turns your engine over when you twist the key.

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A friendly note

Information here is general guidance, not a diagnosis. Always speak to a qualified mechanic before parting with cash.

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