A magnetic shunt, also known as a magnetic bypass or magnetic short circuit, is a technique used in electrical engineering to reduce core losses in transformers and other magnetic devices. Core losses occur primarily due to hysteresis and eddy current losses within the magnetic core material. Hysteresis loss is a result of the energy dissipated when the magnetic domains in the core material repeatedly reverse their magnetization direction in response to the changing magnetic field. Eddy current loss is caused by circulating currents induced within the core material due to the changing magnetic field.
The role of a magnetic shunt in reducing core losses involves providing an alternate low-reluctance path for the magnetic flux generated by the alternating current (AC) applied to the device. This shunt path diverts a significant portion of the magnetic flux away from the main core, effectively reducing the magnetic flux passing through the core and thereby mitigating hysteresis and eddy current losses.
Magnetic shunts are typically constructed using materials with high magnetic conductivity and low electrical conductivity. These materials offer a low-resistance path for the magnetic flux to follow, while minimizing the induction of eddy currents. The shunt is strategically placed to divert a controlled amount of magnetic flux away from the core region. This redistribution of the magnetic flux helps to reduce the overall core losses and improve the efficiency of the magnetic device.
In summary, the primary role of a magnetic shunt in reducing core losses is to provide an alternative path for magnetic flux, which helps mitigate hysteresis and eddy current losses, leading to increased energy efficiency in transformers and other magnetic devices.