Summary:
A German university has developed a method that reduces the leakage current in transformerless chargers for electrical vehicles. This has been proven to reduce leakage current considerably, even to zero. This invention could be utilised in all battery-based electric vehicles, whether all-electric or plug-in hybrid. Licensees are sought. A technical co-operation agreement is also offered.
Description:
The number of electric vehicles that are being registered is increasing significantly each year. The efficient charging of the drive battery is a key technology for the continued success of electric vehicles on the market. In this context, attention has recently turned to transformerless on-board charger concepts. Given the known and considerable leakage capacitance of the battery and the connected high-voltage system, special care must be taken with transformerless chargers to ensure that high leakage current is not generated to ground and through the protective earth (PE) conductor.
The patent-pending invention from a German university uses a method that does without an additional compensation circuit for leakage current, instead using the charger’s inherent DC-DC (direct current) stage that connects its link to the battery (see figure). This DC-DC stage makes it possible to effectively compensate for low-frequency pulsating battery potentials and the resulting unwanted leakage current, such as those that occur particularly with transformerless on-board chargers for electric vehicles on various AC (alternating current) grids. This has been proven to reduce leakage current considerably, even to zero.
All battery-based electric vehicles, whether all-electric or plug-in hybrid, could utilize this circuit in the future with a suitable control mechanism.
The German university offers interested companies the opportunity to license and continue to develop this technology with the inventors. The invention is directed to automobile manufacturers or their suppliers and to battery manufacturers who would like to make use of the technology.
Type (e.g. company, R&D institution…), field of industry and Role of Partner Sought:
All battery-based electric vehicles, whether all-electric or plug-in hybrid, could benefit from this circuit in the future with a suitable control mechanism. All major car manufacturers and charging component suppliers are currently working on efficient charging concepts for electric vehicles in order to reduce charging time and costs (in material and electrical operating losses) and to increase range by, e.g., reducing weight.
The German university offers interested companies the opportunity to license and implement the technology in products and processes and to continue to develop this technology with the inventors.
Together with the inventors from the university, the technology can be further developed to increase the Technology Readiness Level (TRL currently 3) or the technology can be adapted to the product needs of the cooperation partner.
Stage of Development:
Field tested/evaluated
Comments Regarding Stage of Development:
The simulation results are proof of concept for the technology and a prototype is planned for completion by the end of 2021.
IPR Status:
Patent(s) applied for but not yet granted
Comments Regarding IPR Status:
An application has been submitted to the German Patent and Trademark Office, with subsequent applications in other countries possible in the priority year.
External code:
TODE20211126002
