POWER TRANSMISSION SYSTEM

• US 20140015340A1
• Filed: 03/27/2012
• Published: 01/16/2014
• Est. Priority Date: 03/30/2011
• Status: Abandoned Application

• Current Assignee: Equos Research Co., Ltd. (Aisin Corp.)
• Original Assignee: Equos Research Co., Ltd. (Aisin Corp.)
• Inventors: Ito, Yasuo, Yamakawa, Hiroyuki
• Application Number:
  US14/008,664
• Publication Number:
  US 20140015340A1
• Time in Patent Office: Days
• US Class Current: 307/104
• CPC Class Codes: B60L 2210/30 AC to DC converters
• CPC Class Codes: B60L 2210/40 DC to AC converters
• 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 53/36 by positioning the vehicle
• CPC Class Codes: B60L 53/38 specially adapted for charging by inductive energy transfer
• CPC Class Codes: H01F 38/14 Inductive couplings for wireless supply or distribution of electric power using inductive coupling H02J50/10
• CPC Class Codes: H02J 2310/48 for electric vehicles [EV] or hybrid vehicles [HEV]
• CPC Class Codes: H02J 50/05 using capacitive coupling
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02J 50/20 using microwaves or radio frequency waves
• CPC Class Codes: H02J 50/90 involving detection or optimisation of position, e.g. alignment
• 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 10/72 Electric energy management in electromobility
• CPC Class Codes: Y02T 90/12 Electric charging stations
• CPC Class Codes: Y02T 90/14 Plug-in electric vehicles

Abstract

A power transmission system includes: a switching element that converts a DC voltage into an AC voltage of a predetermined frequency to output; a power-transmission antenna unit into which the output AC voltage is input; a current detection unit that detects current flowing through the power-transmission antenna unit; a peak hold unit that acquires a peak value of current detected by the current detection unit; a timer unit that measures a timer value of a difference in time between when the switching element is turned ON and when a zero current is detected by the current detection unit; a frequency determination unit that determines the frequency based on the peak value acquired by the peak hold unit and the timer value measured by the timer unit; and a control unit that drives, based on the frequency determined by the frequency determination unit, the switching element to transmit power.

Claims

1. A power transmission system, comprising:

a switching element that converts a DC voltage into an AC voltage of a predetermined frequency to output;

a power-transmission antenna unit into which the output AC voltage is input;

a current detection unit that detects current flowing through the power-transmission antenna unit;

a peak hold unit that acquires a peak value of current detected by the current detection unit;

a timer unit that measures a timer value of a difference in time between when the switching element is turned ON and when a zero current is detected by the current detection unit;

a frequency determination unit that determines the frequency based on the peak value acquired by the peak hold unit and the timer value measured by the timer unit; and

a control unit that drives, based on the frequency determined by the frequency determination unit, the switching element to transmit power.

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

the frequency determination unit calculates efficiency of the switching element to determine the frequency.

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

the frequency determination unit references a predetermined table to determine the frequency.