Method, apparatus for operating a conduction assembly, start device, and computer-readable medium

An apparatus of operating a conduction assembly, the conduction assembly being coupled between an AC power supply and an inductive load and comprising a first switch device and a second switch device which are in anti-series connection, the first switch device comprising a first body diode in anti-parallel connection with the first switch device, and the second switch device comprising a second body diode in anti-parallel connection with the second switch device, the apparatus comprising:

• a current sampling device for sampling the current in the conduction assembly;
• and
• a controller communicatively connected to the current sampling device and configured to perform a method, comprising:
• conducting the first switch device and the second switch device at a first conduction angle in a first cycle;
• and
• conducting the first switch device and the second switch device in a second cycle at a second conduction angle that is greater than the first conduction angle,
• wherein in the first cycle and second cycle, a turn-off timing of the first switch device or the second switch device in anti-parallel connection with the first body diode or second body diode having a conduction direction the same as a current direction is determined based on the current flowing through the conduction assembly.

A start device, comprising:

• a conduction assembly, being coupled between an AC power supply and an inductive load and comprising a first switch device and a second switch device which are in anti-series connection, the first switch device comprising a first body diode in anti-parallel connection with the first switch device, and the second switch device comprising a second body diode in anti-parallel connection with the second switch device, the start device configured to perform a method comprising:
• conducting the first switch device and the second switch device at a first conduction angle in a first cycle;
• and
• conducting the first switch device and the second switch device in a second cycle at a second conduction angle that is greater than the first conduction angle,
• wherein in the first cycle and second cycle, a turn-off timing of the first switch device or the second switch device in anti-parallel connection with the first body diode or second body diode having a conduction direction the same as a current direction is determined based on the current flowing through the conduction assembly.