Distribution network


Distributed Energy Resources (DER’s) are providing to be a disruptive influence with respect to manage ESO medium voltage distribution grid. Lithuania is currently undergoing a significant shift in its energy landscape to achieve its goal of attaining national energy independence. One key aspect of this transition is the rapid growth of new solar and wind park connections to 10-35 kV distribution network.

Managing DER generation capacity efficiently and autonomously with existing Distribution Management Systems becomes a challenging task.


Due to growing number of DER’s connected to 10-35 kV distribution network, following challenges arises:

  • Non-firm connections: Non-firm connection contracts, which are subject to curtailment during grid congestion events or network maintenance works.
  • Limited capacity during N-0 events:  Limited capacity on medium voltage grid and 110 kV primary substations during N-0 operation (emergencies, planned grid maintenance works). The capacity of the medium voltage grid and the 110 kV primary substation is constrained.
  • What if grid analysis: Planning grid maintenance works, improving fault Location Isolation and Service Restoration (FLISR) functionality, grid modeling with “what if” load flow scenarios are needed considering DER generation capacity.

These challenging grid conditions requires real time generator supervision and direct control if needed to ensuring grid stability.

Current General Electric ADMS system which ESO use does not have such capabilities to efficiently and autonomously supervise and control existing generators.


GE’s Adaptive Network Management (ANM) technology for real-time DER management.

The solution comprises of GE’s Adaptive Network Management module, which is designed to monitor and control the power generation of Wind Farms, Solar Farms and other Generators connected to the Distribution network and ensure that the total generation does not exceed predefined network constraints like current, power, voltage.

ANM periodically checks network constraints for limit violations. Upon detecting a violation (e.g., reverse flow to higher voltage levels) ANM will carry out specific actions against the generators bound by the constraint to return the network to safe running conditions. Actions include sending requests to generators to curtail generation on a pro-rata or LIFO basis, or cut off generation altogether, depending on the severity of the violation.

The ANM solution is adaptive—it understands current network running conditions, maximizing generation whilst staying within the configured limits, aiming to maximize renewable generation, as it continually monitors and maximizes available distributed generation.


Preparation stage to initiate a pilot project. GE ANM module control scheme will be deployed onto current ESO test environment. One 10 kV network area will be used for ANM scheme pilot, curtailing 2 PV plants depending on grid topology. In this topology voltage and current constrains will be supervised, curtailing generators at certain grid topologies/configurations during planned or unplanned grid outages.

Want to know more? Contact our Innovation expert Ernestas Zimkus - [email protected]