An innovative solution is the use of a drive voltage frequency converter (VFC) as a converter for charging EV batteries and integration with the power system of industrial companies, providing wide opportunities for cooperation between various generating units, including renewable energy.

Characteristic features:

• Low cost – VFC cost + rectifier cost (10% of VFC cost), the cost depends on the converter power; 100% use of power electronic components produced on a large scale on the global market.
• High EV charger efficiency of 98% resulting from VFC efficiency.
• Impact on energy quality - a DC microgrid connected to the DC voltage circuit of the drive frequency converter relieves the industrial power system and improves energy quality indicators. Reducing the carbon footprint by using a DC microgrid, which is a local DC network powered by renewable energy that is used for the company's own needs (providing "clean energy").
• The charging power reaches 2.5MW and results from the drive power of frequency converters.
• No need to expand the existing network to integrate it with an EV charger.
• An important issue is to adapt the frequency converter drive software to the EV battery charging strategy.

The solution is protected by 3 Polish patent applications P-434784, P-434786, and P-434787 of July 24, 2020.

The target groups of this solution may be any enterprises that use electric drive systems in their activities, as well as other entities from various industries whose functioning depends on the uninterrupted supply of basic utilities, e.g. local government units, hospitals, and offices. The location of EV battery fast charging stations in, eg. industrial plants enables the rapid development of vehicle fast-charging infrastructure with minimal financial outlays. Locating a mobile fast-charging station near an electrical switchboard with drive frequency converters can significantly shorten the time needed to charge the battery of a self-propelled work machine. The only investment outlay is to adapt the existing plant power grid to use renewable energy for production purposes and to charge EV vehicles.

The use of standard power electronic components on an industrial scale will enable staff to be trained in specialized training and service facilities of the manufacturer. With the increased number of solutions of this type used in the region, it is possible to appoint specialized local companies to assemble and disseminate the proposed installation.

We see the VolFreCon entry in the following development phases:

1. IDEA: preparation of a set coupling an industrial vehicle battery with a 500 kW drive frequency converter and preparation of software for the drive converter managing battery charging (DC power supply according to the programmed charging scenario).
2. START-UP: development of a series of sets adapting drive converters for battery charging, certification, and the start of small-series production.
3. SCALE-UP: expanding the circle of recipients, mass information in Poland and abroad, developing and making available license agreements for foreign markets.

The essence is to use and integrate existing commonly available components to create a new and affordable solution for charging electric vehicle batteries.