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Circuit Simulation for Power Electronic Equipment

Circuit simulation reduces the number of prototyping times, and helps shorten the product development period and save R&D costs

"Circuit simulation" using a computer contributes to resolving critical challenges in product design, including shortening development time and reducing costs.

The development of inverters and uninterruptible power systems (UPS) typically involves prototyping for evaluation after circuit design. If the required performance was not satisfied, the causes of any insufficient specifications are investigated, and then another round of prototyping takes place to re-validate the specifications. This cycle used to be repeated two to three times.

The circuit simulation can identify factors that could adversely affect product quality so that measures may be taken prior to the evaluation of a physical prototype. With this method, it is only necessary to make a physical prototype once.

For example, circuit simulation was employed in the design of a bus bar, the copper plate that helps each part pass electricity. This shortened the development time of the large-capacity UPS from six months to four, reducing R&D costs by 30%.

A bus bar is a copper plate allowing current to flow to each component


Operations that rely on the know-how of skilled engineers were expressed in formulas to achieve fixed adjustment and evaluation.

Power electronic equipment such as inverters and UPSs converts power through a power semiconductor being switched on or off. It is necessary to seek the optimal switching speed considering the impact of voltage and heat to achieve energy-saving specifications. Circuit simulation can express in formulas the operations that have conventionally been performed by experienced engineers or on the basis of the experiment results using a physical product, allowing engineers to digitally adjust and evaluate a prototype in a certain quality.

Circuit simulation applications are expanding, including the development of a power conditioner with the latest SiC power semiconductors.

Voices of developers

Breaking conventional ideas on the development of power electronic equipment.

With the cooperation of the power semiconductor engineers in the Matsumoto Factory, we came up with hundreds of formula models. After much trial and error, we have finally completed a serviceable tool.

One of our strengths is that we are equipped with technologies for both power semiconductors and power electronic equipment. To maximize this benefit, we expect that this simulation will interface communication among design engineers in both areas to further foster their collaboration.

We will further improve analysis precision without making compromises and polish up the tool to make it more user friendly. Furthermore, we want to break the industry's conventional ideas on the development of power electronic equipment.

Power Supply Technology Development Department, and Control Technology Development, Power Electronic Technology Development Center, Core Technology Laboratory, Corporate R&D Headquarters

The article and the affiliations are at the time of coverage.