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The cyberphysical power system resilience testbed implements, tests, verifies, and evaluates cyberphysical resilience solutions for power systems integrated with a communication infrastructure. It offers a platform for real-time simulation of power systems in concert with real-world monitoring, control, and protection.

In this paper, for supporting the medium voltage dc (MVDC) shipboard power system, an energy storage management (ESM) system based on fuzzy logic (FL) has been proposed and its performance with a proportional-integral (PI) control based ESM system is compared. In order to support the peak demand and pulsed load, a hybrid energy storage system incorporating high energy density storage (battery) and high power density storage (supercapacitor) is proposed. For energy transfer among the energy storages and the MVDC system, bidirectional dc–dc converters with dual active bridge (DAB) configuration are used. With the change of the bus voltage and load power demand, the ESM systems provide instantaneous reference powers for charging or discharging of the battery and supercapacitor. The reference powers for the battery and supercapacitor are sent to the respective controllers of the DAB converters. Two power sharing strategies are designed to share power among multiple energy storages. The MVDC shipboard power system with the generators, loads, battery, and supercapacitor with DAB converters are modeled in SimPowerSystems. Simulation results are used to make a comparison of performances of the FL and PI controller based ESM systems. Finally, controller hardware-in-the-loop based experimental results are added to demonstrate the effectiveness of the controller.

Industrial control systems (ICS) are becoming more integral to modern life as they are being integrated into critical infrastructure. These systems typically lack application layer encryption and the placement of common network intrusion services have large blind spots. We propose the novel architecture, Cloud Based Intrusion Detection and Prevention System (CB-IDPS), to detect and prevent threats in ICS networks by using software defined networking (SDN) to route traffic to the cloud for inspection using network function virtualization (NFV) and service function chaining. CB-IDPS uses Amazon Web Services to create a virtual private cloud for packet inspection. The CB-IDPS framework is designed with considerations to the ICS delay constraints, dynamic traffic routing, scalability, resilience, and visibility. CB-IDPS is presented in the context of a micro grid energy management system as the test case to prove that the latency of CB-IDPS is within acceptable delay thresholds. The implementation of CB-IDPS uses the OpenDaylight software for the SDN controller and commonly used network security tools such as Zeek and Snort. To our knowledge, this is the first attempt at using NFV in an ICS context for network security.

To overcome the drawbacks of chemically propelled shells, electromagnetic railgun (EMRG) technology may become a vital part of shipboard power systems as a high-dynamic pulsed load. An Electromagnetic launcher or railgun uses combined electric and magnetic fields to develop Lorentz force on a projectile by flowing current though the rails. In this paper, a detailed electrical model of the EMRG is developed with the governing equations considering the impacts of contact velocity skin effect and contact resistance. A supercapacitor, as a high power density device, is used as the energy source for the railgun. A model is then developed to integrate EMRG within a medium voltage direct current (MVDC) shipboard power system using a DC-DC boost converter. The proposed model for the operation of EMRG with supercapacitor is applied on a sample MVDC shipboard power system using Simulink/SimPowerSystems. Simulation results show that the DC-DC converter supplies the required charging power of the supercapacitor from the MVDC power system, and the supercapacitor smoothly delivers demanded power to the EMRG.

We present a small-signal stability study of a coupled synchronous generator and inverter system, where the inverter is controlled by virtual oscillator control (VOC). VOC is a recently proposed grid-forming inverter control strategy, which acts on faster time scales compared to droop control. In our study, we leverage a scalable VOC controller (that is by design agnostic of power levels) to test the system's small-signal stability at different inverter penetration levels. The impact of rotational inertia, reactive power support, and filter parameters on stability is then investigated. Results highlight possible issues that might arise in these mixed machine-inverter systems further motivating the need to develop next generation stabilizing grid-forming controllers.

This paper introduces a reduced-order aggregated model for parallel-connected inverters controlled with virtual oscillator control (VOC). The premise of VOC is to modulate inverter dynamics to emulate those of nonlinear oscillators with the goal of realizing a stable ac microgrid in the absence of communication, synchronous generation, or a stiff grid. To obtain a reduced-order model for a system of parallel-connected inverters with VOC, we first formulate a set of scaling laws that describe how the controller and filter parameters of a given inverter depend on its voltage and power rating. Subsequently, we show that $N$ parallel inverters which adhere to this scaling law can be modeled with the same structure and hence the same computational burden of the model of a single inverter. The proposed aggregate model is experimentally validated on a system of three parallel inverters with heterogeneous power ratings.

Considering the issues of high electric power demand of various loads including propulsion load and pulsed load, energy storage system has become a vital part of the electric shipboard. In order to meet the transient and steady power demand of the medium voltage direct current (MVDC) power system of the all electric ship (AES), a hybrid energy storage system (HESS) consisting of a battery as high energy density storage and a supercapacitor as high power density storage is used to support the MVDC power system of the AES. In this paper, a Fuzzy Logic (FL) controller based energy storage management (ESM) system is designed which manages energy storages under different loading conditions. For maintaining the AES's bus voltage within the limit and keeping pace with the load power demand, the ESM system provides reference power for controlling the operations of the energy storages. To demonstrate the effectiveness of the energy storages and load management program, a 12kV MVDC power system of AES is designed with gas turbine based generators, modular multilevel converters (MMC), propulsion systems, service loads, pulsed load, energy storages (battery and supercapacitor), and dual active bridge (DAB) converters in SimPowerSystem. Simulation results are provided to show that the operation of the energy storages. FL control can perform effectively even with variation in the load demand.

In order to maintain the bus voltage of a medium voltage DC (MVDC) shipboard power system within the allowable margin with the operation of different types of loads, the energy storage has become an indispensable part of all electric ship (AES). In this paper, a PI controller based energy storage management (ESM) system is designed to control the charging and discharging of the hybrid energy storage systems (HESS) for supporting the MVDC system with the operation of the electric weapons. The HESS consists of a high energy density storage (battery) and a high power density storage (supercapacitor). Dual active bridge (DAB) converters with bi-directional capability are used to interface the HESS with the MVDC system. The ESM system generates instantaneous storage reference power with the change of the bus voltage and load power demand. A low pass filter is used to separate the total storage reference power between the battery and the supercapacitor. The reference powers of the battery and the supercapacitor are sent to the controllers of the DAB converters to control the power exchange between the HESS with the MVDC system. The MVDC shipboard power system with different loads, DAB converter with battery and superconductor are modeled in Matlab/Simulink environment. Simulation results are shown to show the performances of the PI controller based ESM system in different scenarios.

The power management strategy in an MVDC based power system of all electric ship (AES) with Hybrid Energy Storage System (HESS) can greatly affect the energy efficiency of the system. Based on the analysis of power flow, the load characteristics, the power management objectives, constraints and the ease of implementation in MVDC power system, the battery and the super capacitor are considered as the viable storage devices. The dual active bridge (DAB) converter is used to connect HESS with MVDC bus. A fuzzy logic based supervision and control strategy is designed to control the power flow between the energy storage device and MVDC system. The fuzzy logic supervisor can produce the demanded reference power of HESS to meet the load power requirement. The instantaneous reference power is used to control the charging and discharging of HESS. The MVDC power system, the load and DAB converters have been built using Matlab/simulink. The simulation results show that the fuzzy logic supervision and control strategy are capable of managing the power of an MVDC system with HESS.

As the conventional sources of energy (example. oil, gas, coal) are decreasing day by day in the world, renewable energy is going to be the leading energy source in the future. Among all the sources of renewable energy solar PV generation is the potential source for generating power. Penetration of significant amount of solar photovoltaic generation is a challenge for power system stability. Solar PV systems are totally different from conventional synchronous generator. This paper shows the consequences on Bangladesh power system static voltage stability due to large-scale photovoltaic generation. First, the model of PV based generator has been discussed. Then system-loading margin is studied without and with connecting PV based generator. At last the contribution of PV based generator on solving under voltage problem and improving bus voltage is also discussed in the paper.

Input current and power factor improvement of single and three-phase rectifiers by switch mode regulators are usually achieved by switching the output of rectifiers. The output switching makes input current high frequency switched, which is filtered by a small filter to get low input current THD at near unity power factor. In this paper a three phase Buck-Boost rectifier is proposed which is regulated at the input side by a three phase bi-directional switch. Direct input current switching ensures current displacement with input voltage always in phase. The number of diodes to achieve bi-directional input switching and output stage of the three-phase buck-Boost circuit increases. Comparison is made between proposed and conventional circuit under same loads and operating conditions. Results show that the proposed circuit has better performance for variable loads at constant frequency switching. The effect of increasing the number of semiconductor components have not been investigated completely.

Two new topologies of single-phase AC-DC converter using Buck and Buck-Boost conversion with low input current THD and high input power factor are proposed. Instead of using a single phase rectifier followed by a boost DC-DC converter, or using a bridge rectifier with two diodes and two switches, the rectifier's input is chopped at high frequency during positive and negative cycles by a single bi-directional switch to get step-up/step-down ac-dc conversion. Total Harmonic Distortion (THD) of the input current of the proposed circuit with small input current filter is low. Input power factor and the efficiency of conversion of the circuit are high. No additional control is required to achieve the advantages.

A new single phase high performance input side switched AC-DC Cuk converter is proposed. A bidirectional switch is formed by a unidirectional semiconductor switch with proper positioning of the bridgeless diodes at the input ac side for power conversion for both positive and negative half cycle. Because of the high frequency input side switching, the power factor of the circuit is inherently corrected and it requires a small filter to make the input current near sinusoidal with limited THD. The significant improvement in THD makes the circuit a good choice in applications needing AC-DC conversion with power conditioning. The circuit exhibits such performances with variable loads at constant frequency switching with no additional control circuits. The efficiency of the circuit is also satisfactory. Analysis and simulation results of the circuit are obtained by using software simulation. The main advantage of this new AC-DC converter is its superior power quality.

As the recognition in renewable energy is increasing widely, the development of renewable energy can be major alternative energy resources in Bangladesh. This paper represents the impact of large-scale photovoltaic generation on Bangladesh power system stability. First, the model of PV based generator has been analyzed. Then system-loading margin is studied without and with PV based generator. The contribution of PV based generator on solving under voltage problem and improving bus voltage is studied in the paper. This paper will also show the solution of overloading problem of power transformers with solar PV generator. The transient voltage, angle and frequency stability with PV based generator is discussed also.