IEEE Power & Energy Magazine - May/June 2019 - 49

The increased application of power electronics devices is the inevitable result of the
changes being experienced by the system. careful analysis is required to install and operate
power electronics devices. This article describes the use of electromagnetic transient (eMT)
simulation on the French transmission grid to meet these new challenges in the context of
energy transition.

Moving Toward More Complexity
A Long-Term Tendency: Insertion of HVdc Systems and Long ac Cables
The large-scale development of renewable energy sources in transmission grids, along with
public demand to avoid construction of new overhead lines,
has led to increased applications of long high-voltage (hV)
underground cables, the addition of dynamic reactive power
support, and new hVdc links using underground dc cables.
The increasing penetration of power electronics-based
devices in the network will have a significant impact on
grid performance and reliability. power electronics devices,
such as hVdc converters, flexible alternating current transmission systems (FAcTss), and wind power plants, require
improvements in control and protection systems and understanding of dynamic behavior, which is more complex than
for standard ac devices. Thus, specific skills and tools are required to study this technology.

An Operator's Experience
Using Electromagnetic
Transient Simulation

EMT Simulation Becomes a Mandatory
Study Tool Due to Grid Complexity
eMT simulation provides the most advanced solution to model the transmission grid in
detail. numerical simulation tools can offer detailed modeling of hV components and controls while maintaining a good compromise among solution times, accuracy, and flexibility. The use of eMT analysis tools to test new technical solutions has become increasingly
important. eMT studies performed for the installation of new equipment on the grid ensure
the highest levels of equipment reliability and availability. eMT-type simulation tools must
provide power system engineers with reliable simulation results, along with advanced visualization and analysis capabilities. The simulation of transient phenomena may require a
representation of network components valid for dc through a frequency up to hundreds of
kilohertz. Although the ultimate objective is to use frequency-dependent models, an acceptable representation of each component throughout this frequency range is difficult and for
most components is not practically possible. in some cases, even if the wideband version of a
model is available, it may exhibit computational inefficiency or require highly complex data.
in addition to intricate technical problems, utilities must deal with various management
issues that address staff capabilities, corporate profitability and strategic planning, and r&d
needs. The key issues include
✔ an obligation to preserve and organize existing expertise
✔ the need to train a large number of new engineers for replacing expected retirements
in the next five to 10 years
✔ the necessity for continued r&d on new and improved simulation tools for power
system planning and design
✔ funding of r&d activities.
Many transmission system operators (Tsos) worldwide share these challenges, which must
be addressed. in response, several collaborative initiatives have been formed. eMT simulation
can be performed in real time or in offline mode to meet different study objectives. This article

By Sebastien Dennetiere, Hani Saad, Yannick Vernay,
Pierre Rault, César Martin, and Bertrand Clerc
may/june 2019

ieee power & energy magazine

IEEE Power & Energy Magazine - May/June 2019

Table of Contents for the Digital Edition of IEEE Power & Energy Magazine - May/June 2019