Page 238 - Decision Making Applications in Modern Power Systems

Effects of electrical infrastructures in grid with high penetration Chapter | 8 203

Further studies include demand-side management and demand response [12],
grid support [13], optimal power flow [14], integrating of flexible distribu-
tion and storages [15], as well as several control strategies for microgrids
islanded operation [5,16 22]. Nevertheless, these works are mainly focused
on individual requirements for each of these technologies operation, whereas
these resource applications are either limited to grid support, in the cases
where the microgrid is operating connected to the bulk system, or for the
preservation of islanded operation. In this perspective, there is still an
opening for works developing integrated applications of these resources for
both connected and islanded operative scenarios, as well as identifying the
effects that these interactions may imply to these resources operation and
grid support.
In this perspective, this chapter proposes a smart coordinated approach
considering multiple applications of these elements and how they may inter-
act with each other to provide even better solutions and novel applications to
the grid during both connected and islanded modes. These work contribu-
tions occur in many levels of distribution system planning and provide a sig-
nificant capacity of investment deferral and enhancement of grid operability.
First, a controlled charging process of EVs and storage units is presented to
avoid possible overcurrents in transformers and transmission lines, as well as
undervoltages at the nodes. Following that, a second contribution is associ-
ated to the prevention of possible outages in distribution networks capable of
operating in islanded mode. For this, local controls are associated with these
units being their responsibility to perform phase balancing and control
actions to sustain the network operation within satisfactory limits. This
provides a significant increase in quality indexes, leading to better social
welfare and reduction of economic losses. Also, a third contribution is
obtained from flexible loads capacity to work as generators, being this aspect
employed to increase the service capacity of the available infrastructure,
providing significant investment deferral in new infrastructures as local gen-
erators and transmission lines, aiding for peak shaving and mitigation of
transmission congestion.
The following integrated contributions from the smart coordinated opera-
tion of renewables and flexible resources can be highlighted:
1. Coordinated operation of DGs, renewables, and flexible resources
2. Flexible resources applied to power system assistance, for example, peak
shaving and mitigation of transmission congestion
3. Islanded operation with coordination between local generation and flexi-
ble resources
4. Improved planning of distribution system
5. Deferral of investments and increase in social welfare
The chapter is organized as follows: Section 8.2 presents the fundaments
for a coordinated operation of local generation and flexible resources.