ELECTRIC POWER TRANSMISSION SYSTEM

• US 20150061580A1
• Filed: 02/27/2013
• Published: 03/05/2015
• Est. Priority Date: 02/29/2012
• Status: Active Grant

• Current Assignee: Equos Research Co., Ltd. (Aisin Corp.)
• Original Assignee: Equos Research Co., Ltd. (Aisin Corp.)
• Inventors: Yamakawa, Hiroyuki, Ito, Yasuo, Hayashi, Koki
• Granted Patent: US 9,270,138 B2
• Time in Patent Office: Days
• US Class Current: 320/108
• CPC Class Codes: B60L 53/122 Circuits or methods for driving the primary coil, e.g. supplying electric power to the coil
• CPC Class Codes: B60L 53/126 Methods for pairing a vehicle and a charging station, e.g. establishing a one-to-one relation between a wireless power transmitter and a wireless power receiver
• CPC Class Codes: B60M 7/003 for vehicles using stored power (e.g. charging stations)
• CPC Class Codes: H01M 10/44 Methods for charging or discharging circuits for charging H02J7/00
• CPC Class Codes: H01M 10/46 Accumulators structurally combined with charging apparatus circuits for charging H02J7/00
• CPC Class Codes: H01M 2010/4278 Systems for data transfer from batteries, e.g. transfer of battery parameters to a controller, data transferred between battery controller and main controller
• CPC Class Codes: H02J 2310/48 for electric vehicles [EV] or hybrid vehicles [HEV]
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02J 50/80 involving the exchange of data, concerning supply or distribution of electric power, between transmitting devices and receiving devices
• CPC Class Codes: H02J 50/90 involving detection or optimisation of position, e.g. alignment
• CPC Class Codes: H02J 7/00034 Charger exchanging data with an electronic device, i.e. telephone, whose internal battery is under charge
• CPC Class Codes: H02J 7/00714 in response to battery charging or discharging current
• CPC Class Codes: H02J 7/007182 in response to battery voltage
• CPC Class Codes: H02J 7/04 Regulation of charging current or voltage
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/7072 Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors
• CPC Class Codes: Y02T 90/12 Electric charging stations
• CPC Class Codes: Y02T 90/14 Plug-in electric vehicles

Abstract

A power transmission system for transmitting electrical energy from a transmission antenna to a reception antenna via an electromagnetic field, including: an inverter for converting DC voltage into AC voltage having a prescribed frequency and outputting the AC voltage; a transmission-side control unit for performing a control for keeping the drive frequency of the inverter at a prescribed frequency, controlling the voltage of the DC voltage inputted into the inverter, and controlling to keep the power value outputted from the inverter constant; a transmission antenna into which the inverter inputs the AC voltage; a rectifier for rectifying the output from the reception antenna into DC voltage; a step-up/step-down unit for stepping up or down and then outputting the DC voltage from the rectifier; a battery charged by the output from the step-up/step-down unit; and a reception-side control unit for controlling the step-up/step-down unit and charging the battery most efficiently.

Claims

1. An electric power transmission system that transmits electric energy via an electromagnetic field from a power transmission antenna to a power receiving antenna, comprising:

an inverter unit that converts DC voltage to AC voltage of a predetermined frequency to output;

a power transmission-side control unit that controls a drive frequency of the inverter unit and a voltage value of DC voltage input to the inverter unit, and controls power output from the inverter unit;

the power transmission antenna to which AC voltage is input from the inverter unit;

a rectifying unit that rectifies an output of the power receiving antenna to obtain DC voltage, and outputs the DC voltage;

a step-up and step-down unit that steps up or down DC voltage output from the rectifying unit to output;

a battery that is charged with an output of the step-up and step-down unit; and

a power receiving-side control unit that controls the step-up and step-down unit in such a way as to charge the battery with maximum efficiency, and thereby controls in such a way that the drive frequency of the inverter unit remains unchanged regardless of a coupling coefficient between the power transmission antenna and the power receiving antenna.

2. The electric power transmission system according to claim 1, wherein:

the power transmission-side control unit controls in such a way as to keep the drive frequency of the inverter unit at a predetermined frequency; and

the power receiving-side control unit controls the step-up and step-down unit in such a way as to charge the battery with a maximum power value.

3. The electric power transmission system according to claim 1, wherein

as the drive frequency of the inverter unit, a higher extreme-value frequency is used out of two extreme-value frequencies.

4. The electric power transmission system according to claim 2, wherein

as the drive frequency of the inverter unit, a higher extreme-value frequency is used out of two extreme-value frequencies.