Glossary

An arc flash (also called a flashover), which is distinctly different from the arc blast, is part of an arc fault, a type of electrical explosion or discharge that results from a low-impedance connection through air to ground or another voltage phase in an electrical system. For more information visit Arc Flash Analysis page.

Analysis to calculate the ampacity and/or operating temperatures of cables in various raceway systems. Scope of the analysis may also include accurate prediction of cable pulling forces is essential for the proper design of cable systems. This knowledge makes it possible to avoid under-estimated and/or over conservative design practices to achieve substantial capital savings during construction. For more information visit Cable Systems.

Studies to strategically place capacitors for voltage support and power factor correction while minimizing installation and long-term operation costs.

We provide complete analyses of project-specific problems and will investigate and determine the sensitive parameters, calculate, and present alternative solutions or offer consultation to implement an effective solution. Engineering Consulting Services uses a streamlined conceptual design process to identify multiple design concepts to the point where they can be evaluated objectively. The concept that survives the evaluation process is subjected to a detailed engineering design in preparation for system modeling.

In a Current Source Converter, the DC current is kept constant with a small ripple using a large inductor, thus forming a current source on the DC side. The direction of power flow through a CSC is determined by the polarity of the DC voltage while the direction of current flow remains the same. CSC uses thyristor valves as switching devices. It is a kind of Line Commutated Converter (LCC) because thyristor can only be switched off when the current through it passes zero, therefore, it requires line voltage for commutation. CSC-HVDC is suitable for high voltage bulk power and long distance transmission projects without the effect of capacitance along the long transmission line.

To determine and evaluate system voltage profiles and component loading conditions, the ratings of system protective devices, and the appropriate size of the battery for a selected load duty cycle.

ETAP stand for Electrical Transient and Analysis Program. It is the most comprehensive analysis platform for the design, simulation, operation, and automation of generation, distribution, and industrial power systems.
It is developed under an established quality assurance program and is used worldwide as a high impact software.

To determine step and touch potentials to evaluate shock hazards in substations or other ground mat environments.

Studies to identify unacceptable voltage distortion and frequencies where harmonic amplification caused by nonlinear loads are present. To evaluate the effectiveness of harmonic filters and tuning reactors.

Precise control of active and reactive power flow is required to maintain transmission system voltage stability. This is achieved via an electronic converter and its ability to convert electrical energy from AC to DC or vice versa. There are basically two configuration types of three-phase converters possible for this conversion process, Current Source Converters (CSC) and Voltage Source Converters (VSC). Modern HVDC transmission systems can utilize either traditional CSC or VSC as the basic conversion workhorse.

Analysis to effectively maintain power voltage and power levels to prevent overloading, brownouts, and under/over voltage conditions.

During the motor starting period, the starting motor appears to the system as a small impedance connected to a bus. It draws a large current from the system, about six times the motor rated current, which therefore results in voltage drops in the system and imposes disturbances to the normal operation of other system loads. Since the motor acceleration torque is dependent on motor terminal voltage, in some cases the starting motor may not be able to reach its rated speed due to extremely low terminal voltage. This makes it necessary to perform a motor starting analysis. The purpose of performing a motor starting study is twofold: to investigate whether the starting motor can be successfully started under the operating conditions, and to see if starting the motor will seriously impede the normal operation of other loads in the system. Read more information about Motor Acceleration Analysis.

The Single-Line diagram is the blueprint for electrical system analysis. It is the first step in preparing a critical response plan, allowing you to become thoroughly familiar with the electrical system layout and design. The One-Line diagram also becomes your lifeline of information when updating or responding to an emergency. An accurate diagram ensures optimum system performance and coordination for all future testing, and can highlight potential risks before a problem occurs.

Studies to plot time-current curves of protective devices in the power system. The objective of the study is to protect each component against system faults and failures while selectively isolating faults with the minimum system disturbance.

Based on the existing failure rates and outage duration times, the objective of this study is to evaluate the probability of electrical components in performing their intended purpose adequately during the system lifetime and under the various operating conditions encountered.

The statistical availability of different subsystems within the electrical system is determined and their effects on the overall system availability is reported. Read more about Reliability & Availability Studies

Using an intelligent load flow that employs techniques to automatically adjust the power system control settings, ETAP can provide device settings to optimize operating conditions within specific system constraints.

Analysis to establish equipment rating for short circuit capabilities and relay coordination studies for better continuity of services under upset conditions. Short circuit analysis is carried out based on guidelines set by ANSI as well as IEC standards

Existing system data and one-line diagrams are used to develop a preliminary ETAP system model. The preliminary (skeleton) model is set up and tailored for various system studies. The model is then completed through job site surveys where all data pertinent to the specified studies are verified. In some cases system data is available through a third party database where ETAP Data Exchange Services can be employed to transfer or synchronize data to and from your ETAP model.

The Single-Line diagram is the blueprint for electrical system analysis. It is the first step in preparing a critical response plan, allowing you to become thoroughly familiar with the electrical system layout and design. The One-Line diagram also becomes your lifeline of information when updating or responding to an emergency. An accurate diagram ensures optimum system performance and coordination for all future testing, and can highlight potential risks before a problem occurs.

Voltage Source Converters operating with the specified vector control strategy can perform independent control of active/reactive power at both ends. This ability of VSC makes it suitable for connection to weak AC networks, i.e. without local voltage sources. For power reversal, the DC voltage polarity remains the same for VSC based transmission system and the power transfer depends only on the direction of the DC current. Self-commutated Voltage Source Converters are more flexible than the more conventional Current Source Converter since they allow controlling active and reactive power independently.