## 3 Electricity Distribution Network Development
### Network Management, Controls, and Supervisory Systems  
Increasing DERs in the power grids, the local energy generation, and the loads can be adjusted to support grid flexibility and congestion management. The two-way power flow and the power electronic interfaces of the DER units create challenges, particularly to the protection systems due to the reduced short circuit currents and the changed direction of fault currents. In addition, information and communication technologies (ICT) are required for managing the DERs and loads locally.  
Advanced control technologies for active distribution network management (ADNM) need to be developed to implement various operation modes. The application in which a developed concept is aimed to use gives the ultimate terms and conditions of operation. For example, a microgrid concept application can be a distribution network-interconnected microgrid or an isolated microgrid [43]. Furthermore, the required functionalities can be, for example, power balancing, congestion management, fault management, resiliency, and response to external orders in utility microgrids [43] or a combination of all the above. The management schemes (and architectures) are developed for achieving (and implementing) these desired functionalities. The ADNM schemes can be coordinated voltage control (CVC) and adaptive power factor control (PFC). The protection and automation systems for the network operation management and the implementation of coordinated control and protection schemes make possible ADNM. The ICT and the remote monitoring systems are the enablers for ADN control.  
Optimal distribution management planning tools for minimizing the operational costs are to be developed for demand-side management (DSM) [44; 45] and Volt/Var control [46], for example. For the LV distribution networks, the ADNM schemes can be active and reactive power flow optimization, unbalance and reactive power compensation at the point of interconnection (POI), the power balance management in the islanded operation, demand response (DR) at POI, as well as current clearing for the non-load switching operation [47].  
The distributed generation (DG) and the consumer DR programs influence the DMS operation by increasing the need to act on real-time operational data, thus increasingly demanding the sensors and information on the power system operation. The DG also affects the traditional DMS applications, such as load modeling and estimation, load flow algorithms, short circuit analysis, relay protection coordination, and fault detection and location, isolation, and service restoration (FLISR) logic. Further, monitoring, control, and data acquisition extend down, even to individual customers, by an advanced metering infrastructure (AMI), DR systems, and home energy management systems (HEMS). The open architecture in the databases (CIM, SOAP, XML, SOA) and the applications permit the improvement in the monitoring and control application of the supervisory control and data acquisition (SCADA) and DMS; integrated Volt/Var control, databases interfacing via a standard interface with a GIS, an outage management system (OMS), or a meter data management system (MDMS) [48].