Protection Apparatus And Protection Method For Driver, And Driver

A driver comprising:

• three three-phase AC power wiring terminals connected to a three-phase AC power;
• a rectifier unit connected to the three three-phase AC power wiring terminals and configured to convert a three-phase AC power to a DC power;
• a DC bus connected to the rectifier unit and configured to receive a DC power;
• an inverter unit, connected to the DC bus and configured to convert a DC power to a three-phase AC power for controlling a motor;
• three three-phase motor wiring terminals, connected to a three-phase motor;
• and
• a protection apparatus including:
• a meter to detect a current flowing through the inverter unit;
• a loop unit arranged between a positive terminal and a negative terminal of the DC bus and operable to connect and disconnect the positive terminal to the negative terminal of the DC bus under control of a drive signal;
• and
• a controller to generate the drive signal in response to power on of the driver, driving the loop unit to connect the positive terminal to the negative terminal of the DC bus, and to determine, based on a detection result of the meter, whether a three-phase AC power is connected to the three-phase motor wiring terminal;
• wherein the meter is configured to detect a current flowing through the inverter unit, the loop unit is arranged between a positive terminal and a negative terminal of the DC bus and is configured to connect the positive terminal to the negative terminal of the DC bus or disconnect the positive terminal from the negative terminal of the DC bus under control of a drive signal, and the controller, is configured to, in response to power on of the driver, control, based on the drive signal, the loop unit to connect the positive terminal to the negative terminal of the DC bus, and determine, based on a detection result of the meter, whether a three-phase AC power is connected to the three-phase motor wiring terminal, wherein in a case that a three-phase AC power is connected to the three-phase motor wiring terminal (55), the controller stops, in response to receiving a start command, the inverter unit from being started, and in a case that no three-phase AC power is connected to the three-phase motor wiring terminal, the controller controls, based on the drive signal, the loop unit to disconnect the positive terminal from the negative terminal of the DC bus, and drives, in response to receiving the start command, the inverter unit to operate.

A protection method for a driver, the driver comprising a three-phase AC power wiring terminal, a rectifier unit, a DC bus, an inverter unit, and a three-phase motor wiring terminal that are successively connected, the protection method comprising:

• connecting a positive terminal to a negative terminal of the DC bus in response to power on of the driver;
• detecting a current flowing through the inverter unit, and determining the current as a detected current;
• determining whether a three-phase AC power is connected to the three-phase motor wiring terminal based on the detected current;
• stopping the inverter unit from being started, in a case that a three-phase AC power is connected to the three-phase motor wiring terminal in response to receiving a start command;
• and
• disconnecting the positive terminal from the negative terminal of the DC bus and driving the inverter unit to operate in response to receiving the start command, and in a case that no three-phase AC power is connected to the three-phase motor wiring terminal.