Lamp unit power supply system

Abstract

A power supply system for illuminating an LED lamp unit 5, having a normal mode of operation in which a mains input 4 of a driver 3 of the LED lamp unit is supplied by mains power 1, and an emergency mode of operation, in which the LED lamp unit is supplied by a charge storage device 19, is disclosed. The system includes an emergency mode converter 21 operable to step-up the voltage from the charge storage device and to supply the mains driver input for illuminating the LED lamp unit.

1 . A power supply system for illuminating an LED lamp unit ( 5 ), having a normal mode of operation in which a mains input ( 4 ) of a driver ( 3 ) of the LED lamp unit ( 5 ) is supplied by mains power ( 1 ), and an emergency mode of operation, in which the LED lamp unit ( 5 ) is supplied by a charge storage device ( 19 ), the system includes comprising an emergency mode converter ( 21 ) configured to step-up the voltage from the charge storage device ( 19 ) and to supply the mains input ( 4 ) for illuminating the LED lamp unit ( 5 ). 
     
     
         2 . The system of  claim 1 , wherein the emergency mode converter ( 21 ) is configured to step-up the voltage from the charge storage device ( 19 ) to a similar voltage to that of the mains power in the normal mode or operation. 
     
     
         3 . The system of  claim 1 , wherein the emergency mode converter ( 21 ) comprises a: flyback; forward; push-pull; half-bridge; buck-boost or SEPIC converter. 
     
     
         4 . The system of  claim 1 , further comprising a controllable switch ( 7 ,  9 ,  11 ) configured to selectively provide mains power ( 1 ) to the mains input ( 4 ) of the driver ( 3 ) in the normal mode, and power from the charge storage device ( 19 ) to the mains input ( 4 ) of the driver ( 3 ) in the emergency mode. 
     
     
         5 . A power supply method for illuminating an LED lamp unit ( 5 ), having a normal mode of operation in which a mains input ( 4 ) of a driver ( 3 ) of the LED lamp unit ( 5 ) is supplied by mains power ( 1 ), and an emergency mode of operation, in which the LED lamp unit ( 5 ) is supplied by a charge storage device ( 19 ), method comprising providing an emergency mode converter ( 21 ) to step-up the voltage from the charge storage device ( 19 ) and to supply the mains input ( 4 ) to illuminate the LED lamp unit ( 5 ). 
     
     
         6 . The method of  claim 5 , wherein the emergency mode converter ( 21 ) steps-up the voltage from the charge storage device ( 19 ) to a similar voltage to that of the mains power in the normal mode of operation. 
     
     
         7 . The method of  claim 5 , wherein the emergency mode converter ( 21 ) comprises a: flyback; forward; push-pull; half-bridge; buck-boost or SEPIC converter. 
     
     
         8 . The method of  claim 5 , further comprising using a controllable switch ( 7 ,  9 ,  11 ) to selectively provide mains power ( 1 ) to the mains input ( 4 ) of the driver ( 3 ) in the normal mode and power from the charge storage device ( 19 ) to the mains input ( 4 ) of the driver ( 3 ) in the emergency mode.