Coordinated fuzzy logic‐based virtual inertia controller and frequency relay scheme for reliable operation of low‐inertia power system

Abstract

Coordination between protection and control devices is crucial for maintaining continuous operation of power systems. Existing strategies suffer from improper coordination of control and protection devices. Moreover, high penetration levels of renewable energy sources result in lowering the overall power system inertia. Therefore, this paper presents a robust fuzzy‐logic control (FLC) method for superconducting magnetic energy storage (SMES) in low inertia power systems. The new proposed FLC enables robust and wide operating range for SMES compared to the widely employed controllers. The proposed FLC method and load frequency control are coordinated to emulate virtual inertia. In addition, a cooperate coordination between frequency relay and proposed controller is preserved to maintain reliable operation of low inertia power systems. To prove the effectiveness of proposed coordination strategy, it has been tested with considering different load and renewable energy sources (RESs) disturbances with varying inertia level of the selected case study. The results demonstrate that the proposed FLC method can achieve robust SMES operation as virtual inertia controller (VIC) at wide operating range. Moreover, cooperative operation of VIC and frequency protection is preserved using the proposed coordination strategy. The power system availability, frequency regulation, and dynamic stability are improved using the proposed method.

Enhancement the Frequency Stability and Protection of Interconnected Microgrid Systems Using Advanced Hybrid Fractional Order Controller

“…However, RESs-based power grids and microgrids (MGs) are suffering from increased OS/US and longer STs due to the reduced inertia [36], [37]. This, in turn, affects the operation of existing protection devices, in particular the DFR devices [5]. Load changes, and/or RESs fluctuations may lead to higher number of disconnection times.…”

“…Few work has been presented in the literature for the coordination between the DFR and LFC in power grids. In [5], the design of the FLC for superconducting magnetic energy storage (SMES) based virtual inertia controller (VIC) for the Egyptian power grid has been presented. The virtual synchronous generator (VSG) for single area power grid has been presented in [38] with studying their effects on digital protection devices.…”

“…The inputted frequency signal is compared with an upper limit (f max , which denotes to the maximum operating frequency limit of MG system) and lower limit (f min , which denotes to the minimum operating frequency limit of MG system). The setting of the upper limit f max is adjusted to 51 Hz in the studied MGs, whereas the lower limit f min is adjusted to 49 Hz [5]. The normal condition is detected when the inputted frequency signal lies between the upper and lower limits ( f min < f g < f max ).…”

“…Another issue of reduced power system inertia is their coordination and effects on existing digital frequency relays [5]. Modern MGs and power systems have higher peak values of overshoot (OS)/undershoot (US) in addition to longer settling time (ST).…”

Hybridization of battery with pico hydel for frequency regulation of microgrids using synchronverter control

“…The control objectives were similar to the previous work, however, the load and source uncertainties were considered for dynamic studies. Recently, a combination of BESS and SC was employed in a grid-connected solar PV system to mitigate the power fluctuations and enhance the system stability [5]. A multivariable fuzzy logic control was proposed to optimize the time constant of the low pass filter for the coordinated operation of SC and BESS.…”