Stateflow-Based Energy Management Strategy for Hybrid Energy System to Mitigate Load Shedding

Abstract

This study investigates the potential application of Stateflow (SF) to design an energy management strategy (EMS) for a renewable-based hybrid energy system (HES). The SF is an extended finite state machine; it provides a platform to design, model, and execute complex event-driven systems using an interactive graphical environment. The HES comprises photovoltaics (PV), energy storage units (ESU) and a diesel generator (Gen), integrated with the power grid that experiences a regular load shedding condition (scheduled power outages). The EMS optimizes the energy production and utilization during both modes of HES operation, i.e., grid-connected mode and the islanded mode. For islanded operation mode, a resilient power delivery is ensured when the system is subjected to intermittent renewable supply and grid vulnerability. The contributions of this paper are twofold: first is to propose an integrated framework of HES to address the problem of load shedding, and second is to design and implement a resilient EMS in the SF environment. The validation of the proposed EMS demonstrates its feasibility to serve the load for various operating scenarios. The latter include operations under seasonal variation, abnormal weather conditions, and different load shedding patterns. The simulation results reveal that the proposed EMS not only ensures uninterrupted power supply during load shedding but also reduces grid burden by maximizing the use of PV energy. In addition, the SF-based adopted methodology is envisaged to be a useful alternative to the popular design method using the conventional software tools, particularly for event-driven systems.

Techno-economic modelling of hybrid energy system to overcome the load shedding problem: A case study of Pakistan

“…The HES is simulated using the MATLAB-Simulink environment. The simulations are performed using real data-set of load shedding and irradiance profile, published in [ 21 , 42 ]. To observe the resiliency of HES in providing uninterrupted supply, two different scenarios are evaluated: one for the summer day and other for the winter day.…”

“…Considering the Pakistani context, numerous analysis on the various sources combination of HES, optimization techniques and planning criteria are reported in the literature [ 15 – 21 ]. However, there are certain limitations of existing studies, which are discussed below.…”

“…Due to the inherent off-grid architecture, the analysis presented do not consider the load shedding conditions from utility grid. On the other side, the grid connected analysis of HES are performed in [ 19 – 21 ]. The authors in [ 19 ] presented the techno-economic analysis of solar-wind-biomass hybrid system, but emphasized toward the economic performance of the designed system.…”

“…In both studies however, the technical performance and reliability of their system were not given the due attention. Besides, the control operation of a HES with a PV battery and diesel generator backup system is described in [ 21 ], recently. The study presented a good analysis of the instantaneous response of energy sources during recurring scenario of grid outage.…”

Multi-Criteria Energy Management with Preference Induced Load Scheduling Using Grey Wolf Optimizer

“…However, this work considered an off-grid scenario where the system was entirely dependent on renewables, and the utility grid was not considered. Whereas, in [14,15] author uses the state flow method to resolve the problem of load shedding while the author does not consider consumer satisfaction. An algorithm for demand satisfaction was developed to achieve maximum consumer comfort at a minimum price for various budget scenarios [16].…”