Interconnection between household microgrid and utility grid

A meter socket adapter (MSA) for connecting a battery energy storage system (BESS) to a household microgrid through a meter combo load center, comprising:

• a housing matching an electricity meter and a meter socket in the meter combo load center;
• a plurality of power conductors that connect among the electricity meter, the meter socket, and the BESS;
• a meter interconnection device (MID) switch for connecting a utility grid or one or more distribution energy resource (DER) devices to supply power to household loads in the household microgrid;
• a MID driving circuit for driving the MID switch to close or open;
• a MID connection detection circuit to verify an electrical connection of a closed MID switch;
• and
• a metering circuit to measure electricity supply from the utility grid to determine whether an outage of the utility grid occurs or not,
• wherein:
• in response to the electricity supply changing from a normal range to an abnormal range, the MID switch is controlled to disconnect between the household microgrid and the utility grid, and to connect the one or more DER devices to supply power to the household loads in the household microgrid;
• and
• in response to the electricity supply changing from the abnormal range to the normal range, the MID switch is controlled to connect between the household microgrid and the utility grid to supply power to the household loads in the household microgrid, and to disconnect the one or more DER devices from the household loads.

A meter socket adapter (MSA) for connecting a battery energy storage system (BESS) to a household microgrid through a meter combo load center, comprising:

• a housing matching an electricity meter and a meter socket in the meter combo load center;
• a plurality of power conductors that connect among the electricity meter, the meter socket, and the BESS;
• a meter interconnection device (MID) switch for connecting a utility grid or one or more distribution energy resource (DER) devices to supply power to household loads in the household microgrid;
• a MID driving circuit for driving the MID switch to close or open;
• a MID connection detection circuit to verify an electrical connection of a closed MID switch;
• a female connector on a side of the housing to receive a male connector of a connection cable being connected to the one or more DER devices;
• and
• a connectorized jumper configured to be inserted into the female connector to maintain normal operation of the meter combo load center without connecting to the one or more DER devices after the connection cable is unplugged from MSA.