GB/T 38775.1-2020Electric vehicle wireless power transfer—Part 1:General requirements (English PDF)

3.1 Primary Device

Primary device refers to an energy transmitting terminal, a device that is coupled to the secondary device to convert electrical energy into an electromagnetic field and directionally transmit it.

3.2 Secondary Device

Secondary device refers to an energy receiving terminal, a device that is coupled to the primary device to receive the alternating electromagnetic field and convert it into electrical energy.

3.3 Wireless Power Transfer; WPT

Wireless power transfer refers to a power supply mode that implements the transmission of electrical energy from the power supply end to the electrical equipment by means of spatial invisible soft medium (such as. electric field, magnetic field and microwave, etc.).

NOTE: wireless power transfer is also known as contactless power transfer (CPT).

3.4 Electric Vehicle Wireless Power Transfer

Electric vehicle wireless power transfer refers to the use of AC or DC power grid (power supply) to provide power for electric vehicle power batteries and on-board devices through wireless power transfer technology.

3.5 Off-board Power Components

Off-board power components refer to power conversion unit that converts the electrical energy of the power grid into the electrical energy required by the primary device.

3.6 On-board Power Components

On-board power components are installed on the vehicle to convert the electrical energy received by the secondary device into DC power through the power converter and supply it to electric vehicles.

5.1 General Requirements

General requirements for the power transfer system include.

5.2 Schematic Diagram

Figure 2 provides a schematic diagram of the principle of an AC input electric vehicle wireless power transfer system. The electric vehicle wireless power transfer system chart is shown in Appendix A. An example of magnetic coupling is shown in Appendix B.

5.3 Principle of Measurement

5.3.1 Coordinate system

The three-dimensional coordinate system that describes the primary and the secondary device is shown in Figure 3. The X-axis is the driving direction. +X signifies the rear direction of vehicle. The Y-axis is perpendicular to the driving direction. The Z- axis is the height. The origin of the coordinate system is the reference point.

5.3.2 Parking location

The installation location of the primary device is shown in Figure 4. The description of the parameters is shown in Table 2.

5.3.3 Offset

The offset in X and Y direction is the deviation between the center point of the secondary side and the zero point, as it is shown in Figure 5. The description of the parameters is shown in Table 3.

5.3.4 Size measurement of primary device

The definition of size measurement of primary device is shown in Table 4.

5.3.5 Measurement of mechanical air gap

The measurement of mechanical air gap is shown in Table 5.

5.4 Installation of Primary Device

5.4.1 Installation mode

The installation mode of primary device includes.

5.4.3 Above-ground installation

Above-ground installation is shown in Figure 7. The primary device is installed with a certain height above the ground. The installation height above the pavement is specified by the manufacturer's installation guidelines.

6.1 Classification Basis

In this Part, the classification basis for magnetically coupled electric vehicle wireless power transfer system has the following two factors.

6.2 Power Level

The classification by input power level of magnetically coupled electric vehicle wireless power transfer system is shown in Table 8.

6.3 Environmental Conditions

In accordance with purposes and environmental conditions, off-board supply devices of magnetically coupled electric vehicle wireless power transfer system may be classified into.

7.1 General Requirements

When off-board supply devices and on-board supply devices satisfy the following conditions, they are interoperable, and the off-board supply devices can implement wireless transmission of electrical energy to electric vehicles.

7.2 Power Level

The interoperability requirements between off-board supply devices and on-board supply devices of the same power level and different power levels are shown in Table 9.

7.3 Rated Working Frequency

Interoperable off-board supply devices and on-board supply devices shall use the same rated working frequency.

7.4 Resonant Circuit

The resonant circuit topology of the primary device shall match the resonant circuit topology of the secondary device.

7.5 Tuning (optional)

The operating frequency of the electric vehicle wireless power transfer system should be tuned.

7.6 System Efficiency

Interoperability requires that system efficiency shall be not less than the minimum limit

9.1 General Requirements

Among the tests required in this Chapter, wireless power transfer devices shall be operated at the nominal voltage, the maximum output power and current, and the safety characteristics shall not be reduced. The environmental testing and related design of the wireless power transfer system shall satisfy.

9.2 Operating Environment Temperature Requirements

The wireless power transfer devices shall be tested under the specified ambient temperature, the highest and the lowest temperature.

9.3 Environmental Humidity Test

The wireless power transfer devices shall be designed to operate between 5% ~ 95% relative humidity. In accordance with different installation environments, one of the following two tests shall be selected.

9.4 Dry Heat Test

In accordance with the requirements in 10.2.3.1 of GB/T 7251.1-2013, conduct the dry heat test. The test shall comply with the requirements of test Sa, Process B in GB/T 2423.24.

9.5 Low Temperature Test

The low temperature test shall comply with test Ab in GB/T 2423.1. […]