2.1.3. Dynamic Charging

The next, more holistic step is supplying vehicles with energy while driving at cruising speed, which eliminates problems like limited range and therefore allows a reduction of battery capacity.

The first major academic project was coordinated by the "Partners for Advanced Transit and Highways" (PATH), led by UC Berkeley [7]. The consortium equipped an electric bus with a pickup system and used a street with a track system (see Figure 1).

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**Figure 1.** Roadway track system of the KAIST project. **Figure 1.** Roadway track system of the KAIST project. The results of the project have proven that inductive charging while driving is tech-

The results of the project have proven that inductive charging while driving is technically working but limited to materials and electronics that have been available at this time. However, the costs of the installation and maintenance of infrastructure must be reduced. Within the last decades many other test tracks have been installed, such as by the KAIST in South Korea for buses, by Bombardier in Germany for tramways, or by Electreon in Sweden and Germany for trucks [15–17]. The results of the project have proven that inductive charging while driving is technically working but limited to materials and electronics that have been available at this time. However, the costs of the installation and maintenance of infrastructure must be reduced. Within the last decades many other test tracks have been installed, such as by the KAIST in South Korea for buses, by Bombardier in Germany for tramways, or by Electreon in Sweden and Germany for trucks [15–17]. nically working but limited to materials and electronics that have been available at this time. However, the costs of the installation and maintenance of infrastructure must be reduced. Within the last decades many other test tracks have been installed, such as by the KAIST in South Korea for buses, by Bombardier in Germany for tramways, or by Electreon in Sweden and Germany for trucks [15–17]. Nevertheless, there have been no efforts to industrialize the production of the components of this technology and their integration into traffic routes.

Nevertheless, there have been no efforts to industrialize the production of the components of this technology and their integration into traffic routes. Nevertheless, there have been no efforts to industrialize the production of the components of this technology and their integration into traffic routes. *2.2. Components of WPT*

#### *2.2. Components of WPT 2.2. Components of WPT* A WPT system in the variant of IPT consists of a primary and a secondary coil, as

A WPT system in the variant of IPT consists of a primary and a secondary coil, as well as the associated power electronics and sensors. The primary system delivers the energy and might be installed in the infrastructure (see Figure 1.). The secondary system receives the energy to supply the vehicle and is shown in Figure 2. The main components are the coil and the ferrite blocks, which are insulated by a resin as well as the connection A WPT system in the variant of IPT consists of a primary and a secondary coil, as well as the associated power electronics and sensors. The primary system delivers the energy and might be installed in the infrastructure (see Figure 1). The secondary system receives the energy to supply the vehicle and is shown in Figure 2. The main components are the coil and the ferrite blocks, which are insulated by a resin as well as the connection cable. well as the associated power electronics and sensors. The primary system delivers the energy and might be installed in the infrastructure (see Figure 1.). The secondary system receives the energy to supply the vehicle and is shown in Figure 2. The main components are the coil and the ferrite blocks, which are insulated by a resin as well as the connection cable.

**Figure 2.** Composition of an IPT module. **Figure 2.** Composition of an IPT module.

**Figure 2.** Composition of an IPT module. Depending on the type of use, charging pads have different coil designs, which result in different production challenges. To give some examples, there are single-sided and Depending on the type of use, charging pads have different coil designs, which result in different production challenges. To give some examples, there are single-sided and double-sided pad structures with e.g., circular, solenoid, H-formed, D-formed, and DDQformed coil designs [18,19]. Depending on the type of use, charging pads have different coil designs, which result in different production challenges. To give some examples, there are single-sided and double-sided pad structures with e.g., circular, solenoid, H-formed, D-formed, and DDQ-formed coil designs [18,19].

#### double-sided pad structures with e.g., circular, solenoid, H-formed, D-formed, and DDQ-**3. Feasibility of Contactless Charging of EVs**

formed coil designs [18,19]. According to the state of the art, several hundred kW have already been transferred to moving vehicle systems (see Figure 3) under certain conditions. At a distance of 17 cm, the South Korean consortium OLEV (On-line Electric Vehicle) has already been shown to have an efficiency of more than 71% at 17 kW, according to official figures. The first test systems established were able to comply with the ICNIRP limit recommendations of 6.25 µT in the relevant areas around the vehicle [15]. topologies and, on the other hand, through the efficient production and integration of these systems in vehicles and on the road. In particular, automated manufacturing processes are needed to reduce system costs, as very high relative costs are created in the initial migration stages to refinance the infrastructure.

According to the state of the art, several hundred kW have already been transferred to moving vehicle systems (see Figure 3) under certain conditions. At a distance of 17 cm, the South Korean consortium OLEV (On-line Electric Vehicle) has already been shown to have an efficiency of more than 71% at 17 kW, according to official figures. The first test systems established were able to comply with the ICNIRP limit recommendations of 6.25

Further research is needed, among other things, to increase efficiency and reduce vehicle and infrastructure costs, on the one hand through innovative energy transmission

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**3. Feasibility of Contactless Charging of EVs**

μT in the relevant areas around the vehicle [15].

**Figure 3.** System for WPT in moving cars [20]. **Figure 3.** System for WPT in moving cars [20].

**4. Production Concepts for Inductive Power Transfer Pads** The current state of IPT pad production is characterized by small lot sizes and manual work. This often results in fluctuations of quality, which can induce lower power transfer efficiency, damage, or reduced service life expectancy. On the other hand, a higher demand leads to higher lot sizes and automated processes. In the following chap-Further research is needed, among other things, to increase efficiency and reduce vehicle and infrastructure costs, on the one hand through innovative energy transmission topologies and, on the other hand, through the efficient production and integration of these systems in vehicles and on the road. In particular, automated manufacturing processes are needed to reduce system costs, as very high relative costs are created in the initial migration stages to refinance the infrastructure.
