Frequency converter low-voltage ride-through (LVRT) supporting apparatus based on super capacitor

The invention discloses a frequency converter LVRT supporting apparatus based on a super capacitor. Currently relatively severe voltage sags caused by certain power grid faults lead to the shutdown of a factory frequency converter. The apparatus is characterized in that a super capacitor energy-storage unit is connected with a frequency converter direct current link through a non-return diode; a frequency converter rectifying unit is prevented for bearing extra super capacitor charging currents by using the unidirectional conduction of the diode; the energy stored by the super capacitor is guaranteed to be only transmitted to a main circuit during a voltage drop period; the input side of a super capacitor charging unit is connected with an AC power supply; the output side of the super capacitor charging unit is connected with the super capacitor energy-storage unit; and a super capacitor voltage-sharing unit is connected with the super capacitor energy-storage unit. The apparatus which makes a common frequency converter have LVRT capabilities can satisfy frequency converter LVRT supporting demands in each industrial field.