1. A motor driving circuit comprising:an inverter configured to convert direct current (DC) power into alternating current (AC) power to drive a motor;
a braking unit comprising a sampling circuit, a discharge circuit and a switch group, the sampling circuit and the discharge circuit being connected to the inverter, the switch group being configured to output an emergency signal when an emergency occurs;
a Microcontroller Unit (MCU) connected to the sampling circuit, the discharge circuit, and the switch group, and configured to control the sampling circuit to detect a voltage across the inverter and obtain a detected value when receiving the emergency signal, compare the detected value to a preset voltage or a preset voltage range, and transmit a control signal to activate the discharge circuit when the detected value is greater than the preset voltage or exceeds the preset voltage range,
wherein the motor driving circuit comprises a switch component, the switch component is a SPDT relay which comprises a coil, a first contact, a second contact, and a third contact, the third contact is connected to the AC power source, the second contact is null, the first contact is connected to a rectifier, when the coil is energized, the third contact is connected to the first contact, and when the emergency occurs, the coil is de-energized, the third contact is connected to the second contact, and
wherein the switch group comprises an interlock switch, and two resistors, the interlock switch and the coil of the SPDT relay are connected in series between a power source and the ground, the two resistors are connected in series between two ends of the coil of the SPDT relay, and a node of the two resistors is connected to the MCU.