Meaning
Passive inductive components are installed on the input or output of power electronics to improve electrical quality. A line reactor consists of a coil of wire that creates a magnetic field to resist sudden changes in current. This impedance buffers the equipment from voltage spikes and reduces the harmonic noise generated by variable frequency drives.
Inductive Impedance
Sudden surges from the utility grid are slowed down as they pass through the magnetic core. The line reactor acts as a low pass filter, allowing the standard frequency to pass while blocking high frequency disturbances. This protects the sensitive diodes and capacitors inside a motor controller from premature failure.
Voltage Balancing
Phase imbalances in the power supply can cause motors to run hot and lose efficiency. A line reactor helps to balance the current across the three phases by providing a consistent load at the point of connection. This improves the power factor of the facility and can reduce the penalties charged by the electricity provider.
Component Protection
Short circuits downstream are partially mitigated by the current limiting properties of the inductor. While a line reactor cannot stop a fault, it slows the rate of current rise, giving fuses and circuit breakers more time to react. This reduces the risk of catastrophic damage to the drive during a catastrophic event.
