Power supply system, power conditioning apparatus, and power conditioning system

A power conditioning apparatus comprising:

• a direct current input end configured to connect to a direct current source;
• an inverter circuit, wherein a first end of the inverter circuit is configured to connect to the direct current input end;
• at least one grid-connected switch,
• a controller,
• a voltage-to-ground detector, and
• at least one alternating current output end configured to connect to a transformer, wherein a second end of the inverter circuit is configured to connect to the at least one alternating current output end through the at least one grid-connected switch;
• and
• the voltage-to-ground detector is configured to:
• when the at least one grid-connected switch is turned off, detect a voltage to ground of the power conditioning apparatus to obtain a first voltage value;
• and
• when the at least one grid-connected switch is turned on, detect the voltage to ground of the power conditioning apparatus to obtain a second voltage value;
• and
• the controller is configured to:
• output alarm information for grounding of a neutral wire of the transformer;
• or
• control the power conditioning apparatus to stop working when a difference between the second voltage value and the first voltage value falls within a preset voltage range.

A power conditioning system comprising:

• a power conditioning apparatus comprising:
• a direct current input end configured to connect to a direct current source;
• an inverter circuit, wherein a first end of the inverter circuit is configured to connect to the direct current input end;
• at least one grid-connected switch,
• a controller,
• at least one alternating current output end configured to connect to a transformer, wherein a second end of the inverter circuit is configured to connect to the at least one alternating current output end through the at least one grid-connected switch;
• and
• a voltage detection end;
• and
• a voltage-to-ground detector, wherein the voltage detection end is configured to connect to the voltage-to-ground detector,
• and the voltage-to-ground detector is configured to:
• when one grid-connected switch is turned off, detect a voltage to ground of the voltage detection end to obtain a first voltage value;
• and
• when the at least one grid-connected switch is turned on, detect a voltage to ground of the voltage detection end to obtain a second voltage value;
• and
• the controller is configured to:
• output alarm information for grounding of a neutral wire of the transformer;
• or
• control the power conditioning apparatus to stop working when a difference between the second voltage value and the first voltage value falls within a preset voltage range.