Decentralized control of a vehicular microgrid with constant power loads

Abstract

Constant power loads may form a major proportion of the system loads in automotive power systems. Without proper control the presence of constant power loads in a multi-converter environment can cause system instability. In this paper, the concept of autonomous control of a dc microgrid is extended to automotive power systems. An autonomous control law is derived for an automotive power system which consists of system of parallel connected boost converters supplying a constant power load. The control law derived using the passivity based approach consists of two stages. The first, primary stage involves a non-linear droop of the microgrid voltage with respect to the current supplied by each of the converters thereby enabling current sharing. The primary controller also damps the oscillations in the dc microgrid caused by the presence of the constant power load. The secondary controller adjusts for the voltage deviations due to the primary controller without affecting the current sharing. The conditions to ensure the asymptotic stability of the equilibrium points are derived. Experimental results are presented to verify the proposed control law.

Advanced Hierarchical Control and Stability Analysis of DC Microgrids

“…The second category involves cases when one has two converters in parallel [102,[209][210][211][212][213][214]. Amplitude death solutions are utilised for stabilisation of DC microgrids with instantaneous CPLs in [209].…”

“…A comparison between [210] and [211] has been done in [212]. Linear methods based on virtual impedance are proposed in [102,213,214] to increase damping. However, unlike [102], the proposed strategies in [213,214] have also incorporated a voltage restoration term.…”

“…Linear methods based on virtual impedance are proposed in [102,213,214] to increase damping. However, unlike [102], the proposed strategies in [213,214] have also incorporated a voltage restoration term. And by contrast, the nonlinear methods [209][210][211] have a wider stability region compared to the linear methods [102,213,214], but it requires global information, such as the size of the CPLs.…”

Passivity-Based Control for DC-Microgrids with Constant Power Terminals in Island Mode Operation

“…Hybrid energy control [19][20][21][22] and PBC-fuzzy logic are studied in [23] and [24]. An automotive power systems application is a PBC of a vehicular microgrid [25]. In HVDC transmission systems, passivity concept is used in modular multilevel converter control [26,27].…”

Real-Time Implementation of Input-State Linearization and Model Predictive Control for Robust Voltage Regulation of a DC-DC Boost Converter

“…In contrast, nonlinear control algorithms are based on a system nonlinear model, which is considered to more realistically describe the converter's behavior and can improve the system robustness in the case of disturbances or parameter mismatches [11], [12].…”