Comparison of integer and fractional order robust controllers for DC/DC converter feeding constant power load in a DC microgrid

Stability of conformable linear differential systems: a behavioural framework with applications in fractional‐order control

“…To demonstrate the advantages of the proposed approach, we solve a problem associated with the stabilisation of a DC–DC power converter feeding a constant power load (CPL), which is a current issue in power electronics [26]. The closest solution to this problem using elements of fractional‐order control can be found in [27], where a sliding mode controller with a fractional sliding surface is considered for analysis. However, it can be noticed in the simulation of Section 4 of [27] that the controller requires the online solution of a traditional fractional‐order Caputo derivative, whose ‘integration’ results in a double integral loop.…”

“…The closest solution to this problem using elements of fractional‐order control can be found in [27], where a sliding mode controller with a fractional sliding surface is considered for analysis. However, it can be noticed in the simulation of Section 4 of [27] that the controller requires the online solution of a traditional fractional‐order Caputo derivative, whose ‘integration’ results in a double integral loop. Additional to the fact that the CPL requires a higher bandwidth than a typical stand‐alone operation, this results in a non‐trivial computational effort.…”

“…Additional to the fact that the CPL requires a higher bandwidth than a typical stand‐alone operation, this results in a non‐trivial computational effort. The limitation of this approach is reflected in the slow‐response converters used for the simulation (see [27, Table A.1]) that contain e.g. and as capacitance and inductance, which in practice have a significant impact on the power density of the converter.…”

Super Twisting Fractional Order Energy Management Control for a Smart University System Integrated DC Micro-Grid

“…The Lyapunov based method showed promising performance , however the energy management unit is not reported in subject work. In [30,31], centralized robust and optimal controllers are reported for stability issues in DC micro-grid, however the effects of communication link such as network delays and its failure have not investigated. In [32][33][34][35][36][37][38] several other nonlinear control methods have been proposed with energy management units but all the presented methods are integer order.…”

“…robust behavior to the measurement noise and oscillations. Several fractional order controllers have been reported in the literature such as DC-DC converters feeding constant power loads [31], robust non integer controller applied to nonlinear dynamic system [38][39] and fuzzy fractional controller to servo systems [40][41]. Based on the above literature survey, this paper proposes a decentralized super twisting fractional order control in-tegrated with energy management unit for the proposed DC micro-grid shown in Figure 1.…”