Control of DC power distribution system of a hybrid electric aircraft with inherent overcurrent protection

Abstract

In this paper, a novel nonlinear control scheme for the on-board DC micro-grid of a hybrid electric aircraft is proposed to achieve voltage regulation of the low voltage (LV) bus and power sharing among multiple sources. Considering the accurate nonlinear dynamic model of each DC/DC converter in the DC power distribution system, it is mathematically proven that accurate power sharing can be achieved with an inherent overcurrent limitation for each converter separately via the proposed control design using Lyapunov stability theory. The proposed framework is based on the idea of introducing a constant virtual resistance at the input of each converter and a virtual controllable voltage that can be either positive or negative, leading to a bidirectional power flow. Compared to existing control strategies for on-board DC micro-grid systems, the proposed controller guarantees accurate power sharing, tight voltage regulation and an upper limit of each source's current at all times, including during transient phenomena. Simulation results of the LV dynamics of an aircraft on-board DC micro-grid are presented to verify the proposed controller performance in terms of voltage regulation, power sharing and the overcurrent protection capability.

Advanced Hierarchical Control and Stability Analysis of DC Microgrids

“…electronic devices, batteries or photovoltaic panels) can be directly connected to the DC bus, reducing the multi AC/DC conversion stages and, thus, avoiding unstable scenarios and mitigating power conversion losses introduced by the frequency and reactive power control. The advantages rendered by DC microgrids have been confirmed in a wide range of industry applications, such as electric vehicles (EVs) [9], electric trains [10], (more-, hybrid-or all-) electric aircrafts [11,12], and electric ships [13]. The benefits of using a DC ship power system have been summarised in [14], as follows:…”

“…The applications of both unidirectional and bidirectional converters are numerous. Droop controlled DC microgrids consisting of unidirectional boost converters have been studied in [56][57][58], while in [12] both unidirectional and bidirectional converters are integrated into the DC framework. A non-isolated soft-switched-integrated boost converter having high voltage gain is introduced in [59] for module-integrated PV systems, fuel cells, and other low voltage energy sources.…”

Distributed Economic Dispatch Scheme for Droop-Based Autonomous DC Microgrid

“…In this case, the primary control proposed in this paper is first compared with the improved droop control in [35] without considering the secondary level and tertiary level. The control scheme in [35] can be described as…”

“…The deviation of different voltage compensation items causes the power and voltage oscillation in turn, as shown in Figure 10c Figure 9. The comparison between the proposed droop control and the one in [35]. (a) the output power of each generator based on the proposed scheme; (b) the bus voltages based on the proposed scheme; (c) the output power of each generator based on the one in [35]; (d) the bus voltages based on the one in [35].…”

A scientometric analysis and critical review of gas turbine aero-engines control: From Whittle engine to more-electric propulsion

“…''In 2018 Braitor et al outlined ''control of DC power distribution system of a hybrid electric aircraft with inherent overcurrent protection. ''102…”