Analysis and Control of Energy Storage in Aircraft Power Systems with Pulsed Power Loads

One of the main challenges in the power systems of future aircraft is the capability to support pulsed power loads. The high rise and fall times of these loads along with their high power and negative impedance effects will have an undesirable impact on the stability and dc bus voltage quality of the power system. For this reason, studying ways to mitigate these adverse effects are needed for the possible adoption of these type of loads. One of the technologies which can provide benefits to the stability and bus power quality is Energy Storage (ES). This ES is designed with the capability to supply high power at a fast rate. In this paper, the management of the ES to mitigate the effects of pulsed power loads in an aircraft power system is presented. First, the detailed nonlinear model of the power network with pulsed power loads is derived. Due to the large size of this model, a model order reduction is performed using a balanced truncation and a second order approximation. The three types of models are then compared in both time and frequency domain. Lastly, a Model Predictive Control (MPC) strategy is designed for the ES. The objective of the MPC is to reduce the dc bus voltage transient during the turn on and turn off of the load while at the same time minimizing the current drawn from the ES. Impact of the response time and saturation levels of the ES will be discussed. In addition, the proposed controller will be helpful to specify requirements for the design of the ES.