A wave of new solar photovoltaic (“PV”) installations for power generation is hitting many distribution circuits around the country. These installations are typically in the range of 10-2000 kW and comprise of a set of solar PV arrays or trays and inverter modules. The inverters are needed to change the direct-current produced by the arrays to the alternating current standard used by the distribution circuits. The smaller installations connect single-phase, while the larger sizes are three-phase. Interconnection voltage at the point of common coupling between the PV installation and the distribution circuit varies from 120 volt up to 34.5 kilovolt (“kV”).
The concept of integrating these new PV installations with existing distribution circuits is similar to that of interconnecting larger generators in the transmission grid; i.e., the new installation should “do no harm” to the existing system. There are three aspects to this concept as follows. (1) If the existing circuit meets specified standards or criteria of performance, the circuit should still meet the same standard or criteria when the new PV is installed. (2) If the new PV introduces a violation of standard or criteria, mitigation measures need to be included as part of the the new PV’s installation to resolve the violation. (3) If the existing circuit already violates a standard or criteria, the new PV either should not make the violation worse, or limit its impact such that the violation is not worse or even reduced or eliminated.
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So, upcoming power technology courses for Generation X (and those who seek a refresher, shift in focus or broader horizons):
DG to the existing electric grid to ensure it would not adversely impact the operation, reliability and safety of the grid. By its nature, DG would interconnect to lower voltage systems generally classified as “distribution”. The studies can range from relatively quick feasibility assessments to comprehensive studies involving extensive equipment and power system modeling, measurements, and detailed simulations. Specific topics for such studies include: islanding, steady state power flow, voltage regulation, short-circuit, protective relaying, power quality (flicker and harmonic), power factor, system stability, grounding, and ground fault overvoltage. 
