Real-Time Price-Based Optimal Energy Mix in Smart Distribution Network

With the increasing penetration of Distributed Energy Resources (DERs) in Smart Distribution Networks (SDNs), balancing energy mix is a crucial task for distribution system operators. The aggregate consumption, generation, and power exchanged from the upstream network are essential for the energy management system. Appropriate allocation and scheduling of DERs and Energy Storage can minimize the total power drawn from the upstream network. This paper analyzes the Real-Time Price (RTP)-based approach for optimizing the scheduling of DERs and power transfer from the upstream network. The Mixed Integer Linear Programming (MILP)-based optimization approach is used to maximize the total profit made by maintaining optimal energy mix in SDNs by using the energy from DER and energy storage. When the upstream network’s tariff is higher, the energy balance is maintained by DERs and ESSs as far as possible. It is also observed that with the reduction in the energy price from DERs, power export from the SDN to the upstream network is increased

Optimal power flow based coordinated reactive and active power control to mitigate voltage violations in smart inverter enriched distribution network

Voltage violations are the main problem faced in distribution networks (DN) with a higher penetration of inverter-based generations (IBG). Active and reactive power control from smart inverters (SI) can mitigate such violations. Optimal power flow (OPF)-based control provides more accurate operating set points for the coordinated operation of SIs. Therefore, this paper presents a three-phase OPF-based control on SI-enriched unbalanced distribution networks. To consider this, first three-phase model using the current injection model (CIM) is developed. Later, the optimal active and reactive power set points for SIs are obtained by solving a quasi-dynamic optimization problem. The uniqueness of the proposed method is that it regulates the voltage at the affected nodes by obtaining the optimal set points for the smart inverter. The OPF is implemented with a mathematical CIM in Pyomo and solved using the Knitro solver. The proposed method is compared with the sensitivity-based Volt-Var Control (VVC), Volt-Watt Control (VWC), and combined VVC and VWC methods. The effectiveness of the proposed method is verified in a European low-voltage and CIGRE medium-voltage distribution network with 100% penetration. The analysis shows that the OPF-based control optimizes with less network loss and can maintain voltage violations with less reactive power support

Cyber-Physical Co-simulation Framework between Typhon HIL and OpenDSS for Real-Time Applications

Cyber infrastructures have been extensively used for power system monitoring, control, and operation because of the development of new information and communications technology (ICT) in power systems. Deployment of cyber-physical co-simulation in the case of a realistic distribution network is still a big challenge. Hence, to solve the problem of modelling complex distribution networks, a cyberphysical co-simulation framework is proposed in this chapter. The proposed framework consists of a cybernetic layer, a physical layer, and a co-simulation framework between OpenDSS and Typhoon HIL. The cyber layer consists of software and tools to model the distribution system and communicate with the physical layer. The physical layer is the Typhoon HIL real-time simulator consisting of virtual or real controllable devices. A realistic framework to execute the real-time simulation using the Typhoon HIL SCADA system and Python-based co-simulation is created in this chapter. The real-time simulation demonstrates the proposed framework’s effectiveness in observing the distribution network’s voltage profile due to real-time variation in reactive power from the PV

Concise Definition of the Overcurrent Protection System for CIGRE European Medium Voltage Benchmark Network

In the significant widespread transition towards clean energies, there has been an unstoppable trend in integrating renewable energy sources (RSs) in distribution networks. However, the massive penetration of integrated multisources into conventional distribution systems may create several operational problems, such as malfunctioning protection systems. This paper concisely defines the setting for overcurrent protection applied to the CIGRE European (EU) Medium Voltage (MV) benchmark network. The benchmark system is commonly recommended for RSs penetration studies. In this paper, the authors show the calculations and results of the nondirectional and directional overcurrent protection relay in a very educational and detailed way. The definition of the settings considers several operating situations and two short-circuit (SC) types: three-phase and single-line-to-ground. The main contribution of this paper is a well-documented and validated overcurrent protection settings of the CIGR EU MV that can be used for teaching and research purposes

Optimal power flow-based reactive power control in smart distribution network using real-time cyber-physical co-simulation framework

Future distribution networks (DN) are subject to rapid load changes and high penetration of variable distributed energy resources (DER). Due to this, the DN operators face several operational challenges, especially voltage violations. Optimal power flow (OPF)- based reactive power control (RPC) from the smart converter (SC) is one of the viable solutions to address such violations. However, sufficient communication and monitoring infrastructures are not available for OPF-based RPC. With the development of the latest information communication technology in SC, cyber-physical co-simulation (CPCS) has been extensively used for real-time monitoring and control. Moreover, deploying OPFbased RPC using CPCS considering the controller design of SC for a realistic DN is still a big challenge. Hence, this paper aims to mitigate voltage violations by using OPF-based RPC in a real-time CPCS framework with multiple SCs in a realistic DN. The OPF-based RPC is achieved by performing the CPCS framework developed in this study. The CIGRE medium-voltage DN is considered as a test system. Real-time optimization and signal processing are achieved by Python-based programs using a model-based toolchain of a real-time DN solver and simulator. Real-time simulation studies showed that the proposed method is capable of handling uncertain voltage violations in real time

A Modified Version of the IEEE 39-bus Test System for the Day-Ahead Market

Reaching net-zero emissions within the proposed time requires an enormous effort from the energy sector, and it is even more challenging for the electricity infrastructure. This article offers a modified version of the IEEE 39-bus system specifically created to allow zonal day-ahead market (ZDAM) simulations. The system representation is based on the original version of the IEEE 39-bus system but considers the integration of renewable energy resources (RES) in the generation mix: solar and wind. Hourly time series are used to define load profiles and wind and solar power generation. The zonal dayahead energy market information has been created by solving the optimisation problem. Numerical results of the proposed power test system are provided for the yearly ZDAM and steady-state performance, in N and N-l conditions, respectively, through Pyomo and DIgSILENT PowerFactory features

Real-Time Implementation of Two Grid-Forming Power Converter Controls to Emulate Synchronous Generators

Modern power systems are experiencing unprecedented penetration of integrating renewable energy sources (RES) to tackle the so-called climate emergency. But the transition from synchronous generators to converter-interfaced generators also produces a few issues, some of them directly related to the reduction (or lack) of rotational inertia. The voltage source converters (VSCs) enabled with the so-called grid-forming control may provide a solution for the converter-dominated electrical power systems. This paper presents the implementation of two control strategies, Virtual Synchronous Machine (VSM) and Synchronverter (SynC), for converter-interfaced generators in the real-time environment (Typhoon HIL) to emulate synchronous generator (SG) behaviour. The advantages of grid-forming converter control to provide inertia response service and make the system more robust to changes in the active power of loads have been demonstrated in real-time simulations through a scenario of a positive load step connected to the converter

Zonal Day-Ahead Energy Market: A Modified Version of the IEEE 39-bus Test System

The increasing penetration of renewable energy resources (RES) in transmission system operating conditions require a suitable test system and a dataset to cope with current issues. RES penetration remarkably affects day-ahead market outcomes regarding zonal prices and dispatched generation levels. For this purpose, zonal day-ahead energy market models in the presence of RES in the generation mix need to be implemented. In this paper, the IEEE 39-bus system has been suitably modified to include solar and wind generation in the traditional generation mix. Hourly time series are used to define load profiles and wind and solar power generation. The zonal day-ahead market (ZDAM) resolution is simulated by solving a Linear Programming optimization problem employing Pyomo. Furthermore, steady-state nodal analysis is carried out using DIgSILENT PowerFactory, performed over a year horizon

Cyber-Physical Co-Simulation Testbed for Real-Time Reactive Power Control in Smart Distribution Network

Existing electric power distribution systems are evolving and changing as a result of the high renewable energy sources integration. Hence, future smart distribution networks will involve various technical challenges; one of them is real-time monitoring and controlling the network to operate it effectively and efficiently. This paper develops and analyzes a cyber-physical co-simulation testbed for real-time reactive power control in the smart distribution network. The testbed is a two-layer system, with Typhoon HIL 604 representing the physical layer and the other layer as a cybernetic layer. The cybernetic layer is used to model a test system and control reactive power from smart inverters in real-time. The implementation of real-time reactive power control of smart inverters on a CIGRE MV distribution network is shown in this study. The proposed testbed's usefulness in real-time reactive power control is demonstrated through simulation results