Concord Electric Develops EV Wireless Power Supply System Cables

Figure 1: Cables for Wireless Power Supply Systems "KANZACC~EMIC-One"

Concord Electric Co., Ltd. under the Furukawa Electric Group has developed an embedded high-frequency current supply cable "KANZACC-EMIC-One" (Figure 1) for use in electric vehicle (EV) wireless power systems. Sample shipments are scheduled to begin in November 2011, and sales of JPY 100 million will be realized in 2013.

A wireless power supply system is a technology that can supply power to EVs without physical contact such as cables and connectors. The power supply unit is embedded in parking lots and intersections of shopping centers and can be easily recharged by parking. Therefore, it is expected to spread in the future (see this site's report). Concord Electric believes that "in the future, wireless power supply will become the mainstream of EV charging, and therefore it has developed support cables before other companies" (Kyohwa Electric, representative director of the company, Shihichi Shihwa, Figure 2).

KANZACC-EMIC-One developed by Kyowa Electric Line Co., Ltd. is a kind of cable that uses a wireless power supply system power board to supply high frequency and high current to the primary coil (power supply coil) on the ground side (Fig. 3). For effective supply of current, the conductor uses a multi-core insulated wire. This is to suppress the increase in AC resistance due to the skin effect. The cable consists of four cores. Twenty-two copper (Cu) germanium wires were used per core. The frequency is 30kHz and supports 50A. Frequency and current "can be customized by changing the number and width of copper wires used" (the company).

Figure 2: Concord Electric Wire on behalf of the director of the company
Figure 3: Summary of Wireless Power Supply System The idea of ​​KANZACC-EMIC-One is buried in the ground. For this purpose, “waveform processing” is performed, that is, the entire cable outer ring is covered with a wavy metal tube. After waveform processing, in addition to protecting the entire cable, it also functions as a protective film that encapsulates the magnetic flux leakage from the cable.

In order to improve the operability at the time of embedding, Kyowa wire is scheduled to sell cables that have been processed through a connector terminal in the range of 3 to 20 meters for complete sales.