Modelling and Investigation of Control of a Power Infrastructure Resource Management System for a Radio Base Station : A study on sustainable power management for ICT infrastructure.

Abstract: In order to minimize greenhouse gas emissions and operational cost related to the ICT-infrastructure the power management method of a Radio Base Station (RBS) or Base Transceiver Station (BTS) at Ericsson is studied and modelled. The major load demand at RBS’s are due to uplink and downlink data traffic. Ericssons RBS’s contains power resources and energy storage systems that are controlled by a power controller module in order to meet load demand. Such power resources may be AC-grid, generator and photovoltaic cells etc. Using a certain power resource entails a distinct cost and emission. This thesis investigates the influence that the power controller logic has on cost and emission using two frameworks. One framework models the power resource management in the form of a hybrid dynamical system. Using this framework a new management policy is investigated and compared with the current management policy. The second framework investigates the usage of MPC for controlling the power sources during operation. Using this framework a third management policy is introduced and compared with the current implementation. The performance of the three management policies are compared by simulating a standard RBS operation scenario. The results show that during a RBS scenario where the grid will never fail the third management method using MPC outperforms the other two management policies. In the RBS scenario that the grid may fail the second management method outperforms the current implementation. The implication of these results may be that during a scenario of no grid failure it is more advantageous to decrease emission and cost by using a supervisory control method. During a scenario where grid failure may occur using the second management method, where battery is used as more than just a back-up unit, is more advantageous for decreasing emission and cost.