Wireless charging apparatus and method correspondable to voltage range of battery

A wireless charging device comprising:

• a voltage power supply unit configured to supply DC voltage power;
• a filtering unit configured to generate a first level of DC voltage power from the DC voltage power;
• a first inverter configured to convert the first level of DC voltage power into one of a boost charging power, a buck charging power, and a bypass charging power that uses the first level of DC voltage power or driving a vehicle using a two-stage inverter structure to charge the vehicle;
• a driving motor that serves as coupled inductance during charging of the vehicle;
• and
• a second inverter configured to perform one of a boost converter operation mode for the boost charging power, a buck converter operation mode for the buck charging power, a bypass operation mode for the bypass charging power, and a vehicle driving mode for driving the vehicle in connection with the filtering unit, the conversion operation unit, and the driving motor during the charging.

A wireless charging method comprising:

• receiving a wireless charging operation request;
• performing a switching operation for boost or buck depending on whether a vehicle assembly (VA)-side compensation circuit is a series compensation circuit or a parallel compensation circuit;
• estimating a coupling coefficient through an input voltage of a VA-side boost converter or a VA-side buck converter or a current value that has passed a rectifier after the GA-side inverter is operated;
• determining an optimal point for each battery condition according to the coupling coefficient;
• and
• executing a boost converter operation mode or a buck converter operation mode to charge a battery according to the optimal point.