Patent ID: 7301427

Claim:
A transformer, comprising: a first winding part having a first channel; a second winding part having a second channel; a third winding part having a third channel; a primary winding coil wound around said first winding part; a first secondary winding coil wound around said second winding part; a second secondary winding coil wound around said third winding part; a first auxiliary winding coil for sensing magnetic flux balance wound around said second winding part; a second auxiliary winding coil for sensing magnetic flux balance wound around said third winding part; and a magnetic core assembly having a first extension part disposed in said first channel, a second extension part disposed in said second channel, and a third extension part disposed in said third channel; wherein said first and said second secondary winding coils couple to a plurality of lamps for providing energy to said plurality of lamps, and said first and said second auxiliary winding coils couple to a voltage detecting circuit for detecting if said energy provided to said plurality of lamps is substantially equal.