An interconnection system is the equipment that makes up the physical link between DG and the area electric power system (EPS), usually the local electric grid. The interconnection system is the means by which the DG unit electrically connects to the outside electrical power system and provides monitoring, control, metering, and dispatch of the DG unit.
DG applications are interconnected to the area EPS for a reason – the host site wants the ability to use both the DG and the area EPS, sometimes simultaneously. The owner of the area EPS wants an interconnection that is safe and does not affect the area EPS power quality. The complexity of the interconnection system depends on the level of interaction required between the DG and the area EPS.
DG interconnection can result in electric grid operating conditions that would not normally occur – these are called systems impacts. With the advent of IEEE Std 1547, modern interconnection equipment has made great gains by having universal, transparent requirements for interconnection. That standard does not address systems impacts (but helps to minimize them), and also states that it is beyond the scope of the standard to address methods used for performing grid impact studies and mitigating impacts of the grid. However, few changes have been made during grid modernization with the explicit intent to make the grid more accommodating to DR. This is simply not a technology issue - equipment is available, but upgrading or replacing the current equipment that makes up the grid takes time and expense.
Resource Dynamics Corporation Consulting Services
We offer a number of services related to interconnection:
Facilitation of standards and Rulemaking – we help clients develop technical standards and rules pertaining to distributed generation, interconnection, and net metering. We have helped develop distributed generation interconnection standards and rules, such as the District of Columbia Small Generator Interconnection Rule and documents in the IEEE 1547 series of standards. We have also developed white papers on emerging distributed generation interconnection and smart grid issues for client like the Regulatory Assistance Project.