Inductive power transfer system

Abstract

An inductive power transfer OPT system) includes an AC-AC full-bridge converter (T p1 -T p4 ) provided between the primary conductive path (L pt ) and an alternating current power supply (V in ). The system may include a controller for controlling the pick-up device to shape the input current drawn from the alternating current power supply (V in ).

1 . An inductive power transfer (IPT system) comprising
 a primary conductive path adapted to provide a magnetic field for reception by a pick-up device, and;   an AC-AC full-bridge converter provided between the primary conductive path and an alternating current power supply to provide a controlled current to the primary conductive path for provision of the magnetic field.   
     
     
         2 . An IPT system as claimed in  claim 1 , further comprising a controller for controlling the pick-up device to shape an input current drawn from the alternating current power supply. 
     
     
         3 . An IPT system as claimed in  claim 2  wherein the controller modulates the pick-up device to shape the input current drawn from the alternating current power supply. 
     
     
         4 . An IPT system as claimed in  claim 2  wherein the pick-up includes a full-bridge converter having two pairs of complementary switches, and the controller controls the pick-up device by controlling a phase angle between the pairs of complementary switches. 
     
     
         5 . An IPT system as claimed in  claim 1  wherein the alternating current power supply comprises a mains utility power supply. 
     
     
         6 . An IPT system as claimed in  claim 1  wherein the IPT system comprises a bi-directional IPT system. 
     
     
         7 . An IPT system as claimed in  claim 1 , wherein the AC-AC full-bridge converter connects the alternating current power supply to the primary conductive path to provide a current in the primary conductive path having a frequency which is greater than a frequency of the alternating current power supply when power is being transferred to the pick-up device. 
     
     
         8 . An IPT system as claimed in  claim 1 , wherein the AC-AC full-bridge converter connects the primary conductive path to the alternating current power supply to provide a current to the alternating current power supply having a frequency which is less than a frequency of the current in the primary conductive path when power is being transferred to a alternating current power supply. 
     
     
         9 . A primary circuit for an IPT system, the primary circuit comprising:
 a primary conductive path adapted to provide a magnetic field for reception by a pick-up device; and   an AC-AC converter provided between the primary conductive path and an alternating current power supply.   
     
     
         10 . A primary circuit for an IPT system as claimed in  claim 9  wherein the alternating current power supply comprises a mains utility power supply. 
     
     
         11 . A primary circuit for an IPT system as claimed in  claim 9  wherein the primary circuit comprises part of a bi-directional IPT system. 
     
     
         12 . A primary circuit for an IPT system as claimed in  claim 9  wherein the AC-AC converter connects the alternating current power supply to the primary conductive path to provide a current in the primary conductive path having a frequency which is greater than a frequency of the alternating current power supply when power is being transferred to an IPT pick-up device. 
     
     
         13 . A primary circuit for an IPT system as claimed in  claim 9  wherein the AC-AC converter connects the primary conductive path to the alternating current power supply to provide a current to the alternating current power supply having a frequency which is less than a frequency of the a current in the primary conductive path when power is being transferred from an IPT pick-up device to the alternating current power supply. 
     
     
         14 . A method for controlling an inductive power transfer (IPT) system having an AC-AC full-bridge converter provided between an AC power supply and a primary conductive path, the method comprising:
 controlling a pick-up device of the IPT system to shape an input current drawn from an alternating current power supply.   
     
     
         15 . A method as claimed in  claim 14 , further comprising modulating operation of the pick-up device to shape an input current drawn from the alternating current power supply. 
     
     
         16 . A method as claimed in  claim 14 , wherein the pick-up device includes a full-bridge converter having two pairs of complementary switches, and the method comprises controlling the pick-up device by controlling a phase angle between the pairs of complementary switches. 
     
     
         17 . A method as claimed in  claim 14  wherein the alternating current power supply comprises a mains utility power supply. 
     
     
         18 . A method as claimed in  claim 14  wherein the IPT system comprises a bi-directional IPT system. 
     
     
         19 . A method as claimed in  claim 14 , further comprising controlling the AC-AC full-bridge converter to connect the alternating current power supply to the primary conductive path to provide a current in the primary conductive path having a frequency which is greater than a frequency of the alternating current power supply when power is being transferred to the pick-up device. 
     
     
         20 . A method as claimed in  claim 14 , further comprising controlling the AC-AC full-bridge converter to connect the primary conductive path to the alternating current power supply to provide a current to the alternating current power supply having a frequency which is less than a frequency of a current in the primary conductive path when power is being transferred to the alternating current power supply. 
     
     
         21 . (canceled) 
     
     
         22 . (canceled) 
     
     
         23 . (canceled)