A lighting system comprising an LED assembly and a power converter for the LED assembly , the power converter comprising • a switched mode power supply arranged to power the LED assembly , • an AC/DC converter arranged to provide a variable DC supply voltage (Vdc, 160) to the switched mode power supply , • a control unit arranged to receive an input signal representing a required load voltage (V L ) for powering the LED assembly , wherein the control unit is arranged to generate a control signal in order to control the AC/DC converter , in accordance with the required load voltage (V L ); characterised in that : • the control unit is arranged to control the AC/DC converter so as to provide the variable DC supply voltage (Vdc, 160) at a level substantially matching or proportional to the required load voltage (V L ), • the AC/DC converter comprises: - a transformer arranged to provide a variable AC output voltage based on the control signal from the control unit , and - a rectifier arranged to convert the variable AC voltage to the variable DC supply voltage (Vdc, 160), wherein the transformer comprises a primary winding having multiple terminals connectable to an AC power source via a selector element , wherein the control unit is configured to control said selector element by the control signal , the transformer further comprising a secondary winding connected to the rectifier . • a switched mode power supply arranged to power the LED assembly , • an AC/DC converter arranged to provide a variable DC supply voltage (Vdc, 160) to the switched mode power supply , • a control unit arranged to receive an input signal representing a required load voltage (V L ) for powering the LED assembly , wherein the control unit is arranged to generate a control signal in order to control the AC/DC converter , in accordance with the required load voltage (V L ); characterised in that : • the control unit is arranged to control the AC/DC converter so as to provide the variable DC supply voltage (Vdc, 160) at a level substantially matching or proportional to the required load voltage (V L ), • the AC/DC converter comprises: - a transformer arranged to provide a variable AC output voltage based on the control signal from the control unit , and - a rectifier arranged to convert the variable AC voltage to the variable DC supply voltage (Vdc, 160), wherein the transformer comprises a primary winding having multiple terminals connectable to an AC power source via a selector element , wherein the control unit is configured to control said selector element by the control signal , the transformer further comprising a secondary winding connected to the rectifier . - a transformer arranged to provide a variable AC output voltage based on the control signal from the control unit , and - a rectifier arranged to convert the variable AC voltage to the variable DC supply voltage (Vdc, 160), wherein the transformer comprises a primary winding having multiple terminals connectable to an AC power source via a selector element , wherein the control unit is configured to control said selector element by the control signal , the transformer further comprising a secondary winding connected to the rectifier . <EOS>