Mitsubishi Electric: Quality Before Production — How Reliable VFDs Are Built

Mitsubishi Electric: Quality Before Production — How Reliable VFDs Are Built

For Mitsubishi Electric, the quality of a finished product begins not on the production line, but at the earliest stage of design.

In our previous story, we looked at the scale of Mitsubishi Electric's VFD production and the milestone of more than 20 million units shipped. Behind these figures, however, lies more than manufacturing capacity — it is a systematic approach to quality.

Quality starts at the design stage

Mitsubishi Electric applies advanced engineering technologies during VFD development.

These include:

• 3D CAD for structural interference checks;

• structural strength simulation;

• electrical circuit simulation;

• thermo-fluid analysis of power modules.

These technologies allow potential design issues to be assessed at an early stage, before products move into mass production.

In-house power modules

Power modules play a particularly important role. The Mitsubishi Electric presentation describes the power module as the “heart” of the VFD.

At Nagoya Works, Mitsubishi Electric designs and assembles power modules in-house. This allows the company to analyze failures independently, improve quality, and create power modules precisely matched to each inverter.

Inspecting electronics down to the component level

Quality control continues at the component level.

Mitsubishi Electric uses LSI testers, X-ray CT scanning, Scanning Acoustic Tomography (SAT), and cross-section analysis to examine electronic components and their internal structures and connections.

For Mitsubishi Electric, quality is therefore not simply a final inspection — it is a process that begins with the very first stage of product design.

In the third story of our series, we will look at how Mitsubishi Electric tests its VFDs under demanding conditions before they reach the market.