The DC-link capacitor sits on the inverter’s direct-current side. It forms part of the electrical link between the battery supply and the switching power stage. Its design has to account for voltage, ripple current, temperature and the physical connections, rather than capacitance alone.
A matching value is only one requirement
TDK’s automotive capacitor guidance relates component selection to the inverter’s operating conditions. That is why a replacement with the same headline capacitance cannot automatically be treated as equivalent. The assembly’s mechanical and electrical design also matters.
An inverter report should distinguish a suspected capacitor problem from a general high-voltage bus fault. Ask what evidence supports the diagnosis and which other parts of the power path were assessed. A warning naming the DC bus does not name the failed part.
Stored energy needs proper control
A capacitor can retain hazardous energy after the main supply is disconnected. Time alone is not a substitute for the manufacturer’s isolation and verification process. Opening the unit is not an appropriate owner check.
For an enquiry, provide the inverter part number, complete fault report and any history of impact, water ingress or previous internal repair. AXION will confirm whether assessment is supported and what testing can be offered before the assembly is sent in.
Arrange an assessment
For EV and hybrid diagnostics, send the vehicle details and fault report to AXION. We support enquiries from drivers and garages. Workshop, postal and remote options depend on the job and are confirmed before booking.
Technical reference
Read the supporting technical documentation. The referenced design or vehicle application defines its scope; it is not a universal repair procedure.
Related reading
Motor resolver signals and an EV rotor-position fault. Browse the automotive electronics repair library for other systems and symptoms.