Method and apparatus for tertiary control of microgrids with integrated over-current protection

An apparatus for tertiary control with over-current protection, comprising:

• a controller, comprising at least one processor, for:
• calculating, at an upstream controller, at least one unconstrained optimal net intertie target for an area of a power distribution network;
• transmitting the calculated at least one constrained optimal net intertie from the upstream controller to a downstream controller;
• calculating, at a downstream controller, for each resource of a plurality of resources within the area, optimal scheduled current to achieve the at least one unconstrained optimal net intertie target;
• calculating, using the optimal scheduled currents and a plurality of stress coefficients, net scheduled current for each power line segment within the area;
• comparing the net scheduled currents to corresponding stress thresholds to identify any stress violations;
• and
• when the comparing step identifies one or more stress violations:
• when no power line segment remains within the area, transmitting a warning from the downstream controller to the upstream controller for increasing the at least one unconstrained optimal net intertie target;
• or
• when a power line segment remains within the area, reducing, when the comparing step identifies one or more stress violations, the optimal scheduled current for one or more resources, of the plurality of resources, contributing to the one or more stress violations and calculating, when the comparing step identifies the one or more stress violations, updated optimal scheduled current for one or more resources, of the plurality of resources, not contributing to the one or more stress violations.

A computer readable medium comprising a program that, when executed by a processor, performs a method for tertiary control with over-current protection, the method comprising:

• calculating, at an upstream controller, at least one unconstrained optimal net intertie target for an area of a power distribution network;
• transmitting the calculated at least one constrained optimal net intertie from the upstream controller to a downstream controller;
• calculating, at a downstream controller, for each resource of a plurality of resources within the area, optimal scheduled current to achieve the at least one unconstrained optimal net intertie target;
• calculating, using the optimal scheduled currents and a plurality of stress coefficients, net scheduled current for each power line segment within the area;
• comparing the net scheduled currents to corresponding stress thresholds to identify any stress violations;
• and
• when the comparing step identifies one or more stress violations:
• when no power line segment remains within the area, transmitting a warning from the downstream controller to the upstream controller for increasing the at least one unconstrained optimal net intertie target;
• or
• when a power line segment remains within the area, reducing, when the comparing step identifies one or more stress violations, the optimal scheduled current for one or more resources, of the plurality of resources, contributing to the one or more stress violations and calculating, when the comparing step identifies the one or more stress violations, updated optimal scheduled current for one or more resources, of the plurality of resources, not contributing to the one or more stress violations.