GRID4EU Demo 4: Increase the Medium Voltage (MV) network's hosting capacity for DER introducing Active Control and Demand Response of DER (generators, controllable loads and storage)

Within the Grid4EU project, the Italian DEMO4 is located in the Forli-Cesena area (Emilia Romagna region), which is a rural area with high renewable energy integration, mostly photovoltaic (about 40 MW, with 24 medium voltage producers over 500kW), along with low consumptions and power quality issues related to an aging infrastructure. The local distribution network is particularly representative of the southern Europe.

As a matter of fact, because of the reversion of unidirectional flows (since the existing grid is designed for mono-directional flows), the connection of high numbers of DERs might cause low power quality, imbalance between load and generation, protection problems and congestion in MW network. DEMO4 is focused on load-flow optimization at local level with the implementation of an advanced Power Flow Control (PFC) system to increase the hosting capacity of the MV network and maximize the integration of DER into distribution grids. The demonstration will be performed under the coordination and management of ENEL Distribuzione, with the collaboration of other DEMO4 partners: CISCO, RSE, SELTA and SIEMENS AG. Active Control of DER, Demand Response, controllable loads and integration of small-scale storage will be tested under real operating conditions and on large scale.

In order to achieve the earlier mentioned objective, the DEMO4 will:
- Implement Voltage Control in MV networks;
- Manage efficiently and reliably the Disconnection of DER when islanding operations occur;
- Enable ancillary services provided by DER for MV Network operation;
- Test and assess possible services provided by storage to the grid;
- Enable the dispatching of renewable generation on the MV network;
- Review MV DER connection criteria.

For implementing the Active Control of DER, the project will deal with:
- the realization of an advanced Power Flow Control (PFC) system communicating with renewable generators, Primary Substations (HV/MV), Secondary Substation (MV/LV) and storage facility;
- the realization of an “always on” IP standard-based communication infrastructure for real-time data exchange  by using IEC 61850 standard, both wireless and wired technologies;
- the installation of a storage facility (1 MVA / 1 MWh) with possibility to switch over seven MV lines of the primary substations involved.

Moreover, a customer recruitment and selection campaign is needed to realize the demonstrator objectives in terms of consumer behaviour (agreements with active and passive customers potentially interested).
The overall architecture of the main objects involved in the demonstrations is sketched in Figure 1.


Figure 1. Sketch of DEMO4’s overall architecture

More precisely, the architecture of the Demo4 in the SGAM framework is showed in Figure 2.


Figure 2. DEMO4 System Architecture (SGAM framework)

Table 1 below shows the manufacturer/developer partners related to each system. It has to be noticed that the system architecture is composed by several systems, which are, in turn, an aggregation of ICT devices and equipment for grid operations.


Table 1: Manufacturer / Developer related to each system with DEMO4