In this paper, a simple novel control strategy is designed and analyzed for a hybrid energy storage system (HESS). In the proposed method, batteries are used to balance the slow changing power surges, whereas supercapacitors (SC) are used to balance the fast changing power surges. The main advantage of the proposed control strategy is that, the slow response of battery system including dynamics of battery, controller, and converter operation, is overcome by diverting the power surges to the SC system. The proposed method inherits charge/discharge rate control to improve the life span and reduce the current stresses on battery. The proposed method features less computational burden as it uses simple control strategy. The detailed experimental results presented validate the proposed control strategy for sudden changes in photovoltaic (PV) generation and load demand.

Design and Analysis of Novel Control Strategy for Battery and Supercapacitor Storage System

In this paper, a unified energy management scheme is proposed for renewable grid integrated systems with battery–supercapacitor hybrid storage. The intermittent nature of renewable-energy resources (RES), coupled with the unpredictable changes in the load, demands high-power and high-energy-density storage systems to coexist in today's microgrid environment. The proposed scheme dynamically changes the modes of renewable integrated systems based on the availability of RES power and changes in load as well. The participation of battery–supercapacitor storage to handle sudden/average changes in power surges results in fast dc link voltage regulation, effective energy management, and reduced current stress on battery. In addition, the proposed energy management scheme enables the real power transfer along with ancillary services such as current harmonic mitigation, reactive power support, and power factor improvement at the point of common coupling. The proposed scheme is validated through both simulation and experimental studies.

Dynamic Energy Management of Renewable Grid Integrated Hybrid Energy Storage System

Development of hybrid battery-supercapacitor energy storage for remote area renewable energy systems

A renewable energy-based dc micro-grid with hybrid energy storage, consisting of battery and ultracapacitor, is investigated. To achieve high penetration depth of renewable sources into the utility grid, a novel system operation strategy and the corresponding energy management method is proposed. In the operation strategy, the ultracapacitor unit works as the sole voltage source of the micro-grid to support the dc link in both connected and islanding mode. The micro-grid is controlled to deliver/absorb predefined amount of power to/from the utility grid during connected mode and zero during islanding mode. This design will certainly simplify the power dispatching algorithm of the power system and increase the possibility of including large quantities of micro-grids into the utility grid. The energy management method is dedicated to conducting the net power of the micro-grid effectively. The net power is separated into high- and low-frequency components. The high-frequency power is suppressed by the ultracapacitor automatically and the low frequency power is shared by the battery and an adjustment unit. A small-scale dc micro-grid structure with a single dc link is considered for investigation. MATLAB/Simulink simulation results are presented to validate the proposed system operation strategy and the energy management method.

System Operation and Energy Management of a Renewable Energy-Based DC Micro-Grid for High Penetration Depth Application

The power generation from renewable power sources is variable in nature, and may contain unacceptable fluctuations in case of the wind power generation. High fluctuations in power generation may negatively impact the voltage stability of the microgrid. This problem can be alleviated by using hybrid energy storage system consisting of batteries and supercapacitors (SCs) at dc grid. A new control scheme is proposed to control the power sharing between batteries and SCs to match the generation-demand mismatch and hence to regulate the grid voltage. In the proposed control strategy, the SC supplies error component of the battery current in addition to the fast transient power demand. This added feature not only improves the dc grid voltage regulation capability but also reduces the stress levels on the battery and hence increases the life span of the battery. The main advantage of the scheme is that, the uncompensated power due to slow dynamics of the battery is diverted to the SC and keeps the state of charge within the limits for longer duration, as compared to the conventional strategy. The proposed scheme is validated through detailed experimental studies.

DC Grid Voltage Regulation Using New HESS Control Strategy

The energy flow between source and the load of micro grid must be balanced to have a constant dc grid voltage. Due to intermittency in the natural sources and the variations in load, energy balance operation demands storage. The commonly preferred choice of energy storage in micro grid is valve regulated lead acid batteries. When batteries are used as energy storage, due to its low power density, the charge and discharge rate is low. It causes severe stress on the battery under quick load fluctuations and results in increase in the number of charge/discharge cycles. Hence, the lifetime of the battery reduces. The super capacitors have high power density and it can react speedily to quick load fluctuations. However, super capacitors alone cannot be used as energy storage as it cannot supply load for a longer time. Hence, this paper proposes a combined energy storage using batteries and super capacitors with high energy and power density. The photovoltaic (PV) based micro grid with combined energy storage is designed and the control strategy is validated for different atmospheric and load conditions.

Dynamic energy management of micro grids using battery super capacitor combined storage

Cloud computing can be considered as a key tool in the energy management process that reflects effective monitoring, controlling as well as conserving energy. Energy management is a key concern in pepper implementation of smart grid technology. Due to the absence of cloud computing, energy cannot be supplied to a broad range of users as limited storage and memory are present in traditional technology. In the traditional energy management process, various kinds of stability issues can be seen in the absence of any cloud. Concerning all those reasons cloud computing is used in smart grid technology for providing a broad range of energy without interrupting the power supply. On the other hand, smart grid technology reflects a unique network that generates a two-way electricity flow by using various kinds of digital tools and techniques. This innovative technology can easily detect and at the same time react against any kind of issue generated in this technology due to the presence of cloud computing techniques. Compared to traditional technology, a huge level of renewable energy resources are used in smart grid technologies. A less amount of carbon emission reflects the generation of a better future environment. A survey analysis has occurred by taking 51 random people and three questions are asked related to effectiveness of cloud computing on smart grid technology and impact of this technology on the environment. A detailed discussion has also given after analysing survey.

The Role of Internet of Things (IOT) for Cloud Computing Based Smart Grid Application for Better Energy Management using Mediation Analysis Approach

The financial market is combined with many instruments, which supports to function the market without any deviation and helps to develop the economy. The present paper aims to investigate the various types of treasury bills traded in the money markets and its performance and growth from the year 2011-12 to 2020-21. The secondary data were collected from various websites of Reserve Bank of India (RBI), Securities Exchange Board of India (SEBI), and Centre for Monitoring Indian Economy (CMIE). The collected data were analysed by applying simple percentage analysis, Annual Growth Rate (AGR), and Compound Annual Growth Rate to assess the performance of Treasury bill (T-Bills).

R. Sathishkumar

Papers

Dynamic energy management of micro grids using battery super capacitor combined storage

The Role of Internet of Things (IOT) for Cloud Computing Based Smart Grid Application for Better Energy Management using Mediation Analysis Approach

Performance evaluation of treasury bills traded in the money market