Power System studies

Software Modeling and Analysis of Electrical System Response to Varying Operational Contingencies

Power System Studies

Root 3 analyzes FEED designs or previously-built facilities and produces a report that is easily understandable yet is also thoroughly detailed in explaining the methods and standards used to develop conclusions. Root 3 engineers are adept at performing power system studies using several power systems analysis software packages, including:

SKM PowerTools®
ETAP®
EasyPower®
ASPEN Oneliner®

Load Flow

A load flow study is important both during the design phase of the project as well as throughout the useful life of a facility. In the design phase, a load flow study validates that all equipment (cables, transformers, etc.) is specified properly to sustain the continuous load of the facility. The load flow study also determines the worst-case voltage drop that can be expected at the source (service voltage) and at the line terminals of the powered equipment (utilization voltage). As a facility is expanded over time, a periodic review of the system load is required to prioritize system upgrades to ensure that equipment is not overloaded and that voltage will remain within acceptable tolerance limits.

Short Circuit

Short circuit studies are crucial to the effective operation of any electrical system. Short circuit studies verify the adequacy of equipment close & latch, bracing and interrupt ratings. Short circuit study results are also imperative to determining the necessary characteristics of the system’s protection scheme. A short circuit study must include several different failure modes including:

Three-phase fault.
Phase-to-phase fault.
Single-line-to-ground fault.
Double line-to-ground fault.
Open phase fault.

Protective Device Coordination

Coordinating protective devices is the practice of achieving selectivity. Selectivity is the principle that only the faulted piece of equipment on an electrical system should be isolated and de-energized while all else remains operational. Protective device coordination is typically done by creating time vs current coordination (TCC) plots of each current-based protective device in an electrical system. Care must be taken to select a proper coordination time interval (CTI) that addresses the possibility of various inaccuracies (CT saturation, manufacturer tolerances, etc) that can cause miscoordinations and needless loss of load.

Arc-Flash Hazard Analysis

An arc-flash hazard analysis is a critical component to keeping personnel safe. Root 3 Power uses power systems analysis software based on the 2018 revision of IEEE 1584 to quantify the arc-flash hazard incident energy and arc-flash hazard boundary. We are well-versed with all the variables of the empirically derived equations of IEEE 1584. We have the experience to navigate the data collection and software modeling process to yield accurate results without getting mired in insignificant details or causing delays.

Transient Motor Starting

As motors become an increasingly large portion of the load on industrial power systems, it is becoming imperative to study the effect starting motors has on the motor and loads connected to the local power system. A transient motor starting study calculates a motor's ability to both break away from standstill (locked rotor) under a pre-determined load and come successfully up to operating speed without stalling. Transient motor starting also evaluates the voltage drop on local and remote power system buses in response to a motor start, and helps the study engineer determine the most appropriate method of starting a motor.

Transient Stability

Especially important on islanded systems with relatively small generators, a transient stability study can determine a system’s Critical Clearing Time (CCT). The CCT is the maximum amount of time a severe fault can persist on one part of the electrical system before the generators’ speed control or voltage control cannot recover.

engineering services for electrical infrastructure

Power System studies