Multi-terminal flexible direct-current adaptive grid-forming control system, method, device, and medium

A multi-terminal flexible direct-current adaptive grid-forming control method, applied in a multi-terminal flexible direct-current adaptive grid-forming control system, wherein

• the system comprises a plurality of energy systems, a plurality of inverters, a first adaptive grid-forming converter, a transmitting-terminal point of common coupling, a second adaptive grid-forming converter, a plurality of receiving-terminal points of common coupling, and a high-voltage direct-current line, wherein
• the plurality of energy systems are connected to the plurality of inverters, the plurality of inverters are connected to the transmitting-terminal point of common coupling;
• the transmitting-terminal point of common coupling establishes a connection with the high-voltage direct-current line through the first adaptive grid-forming converter;
• the high-voltage direct-current line is connected to the plurality of receiving-terminal points of common coupling through the second adaptive grid-forming converter, wherein a receiving-terminal grid is connected to the plurality of receiving-terminal points of common coupling;
• and
• each of the first adaptive grid-forming converter and the second adaptive grid-forming converter comprises:
• an oscillation phase module, an oscillation amplitude module, an oscillation frequency module, and an oscillator module,
• the method comprises:
• setting power set values of the first adaptive grid-forming converter and the second adaptive grid-forming converter according to loss of the high-voltage direct-current line;
• constructing an adaptive grid-forming control model and determining an alternating-current voltage instruction based on the adaptive grid-forming control model;
• establishing a current inner loop constraint control strategy based on virtual admittance and current clamping, determining a current inner loop control instruction according to the current inner loop constraint control strategy;
• and
• controlling an operation of the multi-terminal flexible direct-current adaptive grid-forming control system based on the power set values, the alternating-current voltage instruction, and the current inner loop control instruction.