Conventional compensation systems, such as capacitor banks, mechanically controlled reactors, and synchronous machines, have long been used to increase steady-state power transfer by regulating voltage in distribution networks in a conventional manner [1][2]. Today, the rapid development of power electronics has enabled the emergence of new equipment and advanced methods for power flow control, voltage regulation, transient stability improvement, and damping of electromechanical oscillations in electrical networks [3]. These devices, known as Flexible AC Transmission Systems (FACTS), based on advanced power electronics technologies, provide technical solutions adapted to new network operation constraints [4][5]. These static devices have made shunt reactive power compensation flexible. Among them, the STATCOM, a static synchronous compensator used in transmission networks, exhibits functional behavior comparable to that of a synchronous machine, while eliminating constraints related to mechanical inertia [6]. Similarly, the DSTATCOM, a component from this family, is power electronics equipment using a voltage source converter that can be connected in shunt to the distribution network and whose purpose is to inject capacitive or inductive current to compensate and control electrical quantities in distribution networks [7 [8]. In the context of reactive power compensation and voltage regulation in distribution networks, R. Madhusudan and al [9] modeled and simulated a DSTATCOM for power quality problems (voltage sags and swells) based on sinusoidal pulse width modulation (SPWM). M. Kumar and al [10] designed and operated a DSTATCOM for improving power quality in electrical distribution networks. G. Gupta and al [11], conducted a comprehensive review of DSTATCOM network control and compensation strategies. C. Chodavadiya and al [12] combined DSTATCOM and DVR to improve the voltage profile of an electrical distribution network. In an electrical network incorporating a DSTATCOM compensation device, the effect of short-circuits can be either mitigated or, in certain cases, result in a modification of the system’s electromagnetic dynamics. The behavior of the DSTATCOM in the face of single-phase, two-phase, and three-phase faults depends closely on the network’s inherent characteristics as well as the fault location. Short-circuits constitute one of the main sources of power quality degradation, particularly voltage sags, voltage variations, and harmonic distortions, affecting power transfer and reactive power exchanges [13].

In this article, the DSTATCOM model is simulated using a control strategy based on pulse width modulation (PWM) combined with a PID controller to reduce fault current oscillations, which constitute one of the most severe disturbances in the distribution network. Simulations were performed in MATLAB/Simulink to validate the device’s effectiveness and compare network performance with and without D-STATCOM.

Electrical distribution networks, as the final link in the supply chain, ensure energy delivery from the transmission network to consumers [14]. This structure can have very significant faults in urban and rural areas, leading to service discontinuity. In this article, the investigated network consists of a three-phase source, a power transformer, two loads, a busbar, and a D-STATCOM connected at the point of common coupling (PCC), as illustrated in Figure 1, in order to provide reactive power compensation and limit fault currents. The network parameters listed in Table 1 were selected to accurately represent a realistic medium-voltage (MV) distribution network.

Table 1.The network parameters.

Figure 1.DSTATCOM coupled to the network [15].

Simulations performed in MATLAB/Simulink show that in the absence of DSTATCOM, single-phase, two-phase, and three-phase faults result in very high short-circuit currents. The integration of DSTATCOM significantly reduces these currents. Figure 4 shows the designed model of the distribution network with fault and DSTATCOM coupling.

Figure 4. Distribution network model with DSTATCOM.

Comparative analysis highlights that DSTATCOM effectiveness depends on the fault type and its location in the network. The regulated action of DSTATCOM based on short-circuit current constitutes an important advantage for protection coordination. DSTATCOM proves particularly effective in severe faults, especially three-phase short-circuits.

This study has shown that DSTATCOM constitutes an effective technological solution for limiting short-circuit currents in distribution networks. Simulation results confirm its essential role in improving network stability during faults. Although this study does not account for constraints related to protection systems and network parameters such as line resistance and reactance, DSTATCOM appears as an economically viable technological solution, particularly suitable for developing country networks.