| 摘要 |
A current sensor including a magnetic sense element having a core which undergoes cyclic saturation. By driving the ferromagnetic core cyclically into forward and reverse saturation the transformer operates in a near zero flux mode. The sensing apparatus may include circuitry for separating the sensed current component from the magnetising current component in the secondary winding of the magnetic sense element. The apparatus may also include correction circuitry to cancel the effects of ripple current on the output due to both the magnetisation current and errors due to the presence of the ripple cancellation circuitry itself. The circuit may also be provided with decoupling means to cancel the effect of voltages reflected back into the primary circuit. Such a sensing apparatus provides electrical isolation between the primary circuit and the sensing circuit, has good bandwidth, and is insensitive to temperature, temperature gradient, mechanical forces, aging (creep) and noise.
|
