| 摘要 |
An apparatus 2 for energizing a component 8 with an alternating voltage. The component comprises a coil 12 wound on a magnetic core 10. A testing device which comprises a measurement system configured to measure a response of the component to the energizing is also described. The component may be a transformer and the coil may have a finite resistance. The apparatus comprises a power source 4 configured to apply a voltage having a first waveform during a first period (14 Fig 7) and a second waveform during a second period (16 Fig 7). The second time period is subsequent to the first time period. The second waveform comprises an oscillating function comprising a sequence of identical waveforms. The first waveform is such that if the coil had zero electrical resistance the variation of flux density with time would change sign, or polarity, at least once in the duration of the first waveforms time period. A corresponding method of energizing a wound component is also described. |
