Ramon Zamora

• Doctor of Philosophy
• Lecturer at Auckland University of Technology

Increasing the replacement of conventional synchronous machines by non-synchronous renewable machines reduces the conventional synchronous generator (SG) inertia in the modern network. Synthetic inertia (SI) control topologies to provide frequency support are becoming a new frequency control tactic in new networks. However, the participation of SI...

Energy poverty is a severe electrification challenge in Nigeria that has affected the country's economic development. The gap between electricity demand and supply continues to increase, and a large percentage of the populace affected are rural dwellers. With the prevailing electricity inaccessibility in rural, renewable energy sources (RES) presen...

Frequency dynamics is one of the important aspects of power system stability. From the frequency dynamics, the operator could plan how is the reliability of the electricity. The frequency can be maintained by controlling the balance between load demand and generation. To maintain the balance of the generation, the governor is playing an important r...

This article proposes a comprehensive multi-functional controller for a hybrid energy storage system (HESS), including a battery and supercapacitor (SC). In the presented method, a V -d P /dt is proposed to control the output power of the battery converter with a slow dynamic response. The traditional V - P droop is employed to regulate the S...

An overview of the adoption extent of the energy business models around the world was undertaken by considering both the developed and developing countries, with the emphasis on the customer-side renewable energy business models. The developed countries have widely adopted energy business initiatives to advance the distributed generation of electri...

With the recent developments in renewable energy generation and addition of power electronic devices, power system dynamics have become extremely complex. One of the challenges faced due to this transition is the sub synchronous oscillations caused by the interaction of renewable energy sources and various components of the power grid. Recently rep...

The proliferation of renewable energy sources (RESs) into the distribution network necessitates the need for the capability to predict the security state of the grid. This paper proposes a density-based clustering and probabilistic classification approach to predict the security state of the modern grid. Firstly, an approach to predict the critical...

In modern distribution network planning and operation, optimal distribution generation (DG) placement has become increasingly important. Consequently, extending the optimal DG placement objectives beyond the commonly used deterministic indices to include probabilistic security indices is essential. This paper proposes a decision tree (DT) classific...

This paper proposes a hybrid method (HM) to improve the accuracy of the short-term individual residential load forecasting. The HM includes an ensemble model (EM), deep ensemble model (DEM), and thermal dynamic model expressed by resistance-capacitance (RC). The EM consists of three predictors of support vector machine (SVM), back propagation neura...

In this study, the optimal tilt angle with respect to the module azimuth angle was investigated for the case of low latitude equatorial region. A replicable methodology for establishing the appropriate rooftop support structure adjustments required to attain the maximum possible solar irradiance on pitched rooftops was proposed. By using the partic...

In a microgrid, a hybrid energy storage system (HESS) consisting of a high energy density energy storage and high power density energy storage is employed to suppress the power fluctuation, ensure power balance and improve power quality. Since the HESS integrates energy storage with slow and fast dynamic characteristics, the control system design i...

A multi-criteria analysis of alternative energy technologies based on sustainable livelihoods framework is presented. A time bound development predicting model derived from a modified heterogenous mean field approach is proposed. The time bound development predicting model and time unbound development predicting model were validated as well as comp...

The increasing number of electricity consumers results in power quality problems in the distribution system. Solar photovoltaic integrated unified power quality conditioner (UPQC-PV) is a widely adopted device that can improve a distribution system's voltage and current quality. This paper presents an optimal design and performance analysis of a un...

The proliferation of renewable energy sources distributed generation (RES-DG) into the grid results in time-varying inertia constant. To ensure the security of the grid under varying inertia, techniques for fast security assessment are required. In addition, considering the high penetration of RES-DG units into the modern grids, security prediction...

Several studies show that grid-integrated renewable energy (RE) sources have the potential to replace conventional synchronous generators in the network. This means the grid will experience low conventional inertia that is currently provided by synchronous generators. Low, unpredictable and time-changing inertia in the power system, as a result of...

The future grid will include a high penetration of distributed generation, which will have an impact on its security. This paper discusses the latest trends, components, tools, and frameworks aimed at 100% renewable energy generation for the emerging grid. The technical and economic impacts of renewable energy sources (RES)-based distributed genera...

Government support is crucial for the competitiveness and success of renewable energy market policies. As an advancement to the previously developed store-on grid (SoG) scheme, this study considered 14 countries to examine the government's role in the SoG scheme. A methodology for evaluating the total government expenditure on the battery energy st...

Although solar photovoltaic systems do not emit greenhouse gases (GHG) during their operation lifetime, their manufacturing, transportation, and construction involves energy use and GHG emissions. In this study a life cycle assessment as well as economics analysis of the solar modules from manufacturing to delivery of the final product were evaluat...

The time-dependent inertia can trigger rapid frequency variations, which have become main concerns in power system stability. Prior understanding of the system inertia will help operators to mitigate the stability issues by applying appropriate measures and executing suitable control schemes. Therefore, this paper proposes a data-driven method to e...

The viability of the store-on grid (SoG) scheme model across 13 selected Sub-Saharan African (SSA) countries was investigated. The individual country's datasets applicable to the SoG scheme and a typical industrial building as a baseline prosumer were used in the evaluation. Two SoG scheme scenarios (A and B) based on solar photovoltaic (PV) module...

A disturbance such as a small load change in the electrical power grid triggers the system to oscillate and may lead to performance degradation of the control system in the generation source unit. To overcome this problem, a power system stabilizer (PSS) is added as a supplementary control in the power system grid to damp the oscillation caused by...

Low and time-changing inertia values due to the high percentage of renewable energy sources (RESs) can cause stability problems in power systems due to rapid frequency instabilities. Inertia monitoring will assist operators to apply suitable actions and more proper control methods to alleviate stability issues. Therefore, this paper proposes an onl...

The benefits analysis of the store-on grid (SoG) scheme, an energy business model for fostering rooftop solar photovoltaic technology in developing countries, is proposed in this paper. An expression for evaluating the feed-in grid rate for the solar energy fed to the grid under the SoG scheme is presented. The results of the SoG scheme were compar...

State of charge (SoC) imbalance and dc bus voltage deviations are significant issues for distributed battery energy storage systems in autonomous dc microgrid applications. Accordingly, a high-pass filter (HPF) based SoC balancing method is proposed to achieve SoC balance by considering different SoCs and capacities; A band-pass filter (BPF) based...

Electric vehicles (EVs) are a viable alternative for a sustainable mode of transportation. A huge penetration of EVs in future will lead to increasing demand in commercial parking lots equipped with charging systems. Hence, this research area is being pursued meaningfully in recent years. This article proposes a transactive energy management system...

This paper deals with managing the load across distribution transformer through demand response and smart battery electric vehicle (BEV) charging techniques. A neighborhood of 40 households connected across a 200-kVA distribution transformer is investigated in this paper. Each house is provided with a single BEV. Residential and BEV loads across ea...

The uncertainty of plug-in electric vehicle (EV) charging behaviour is a crucial factor that not only influences the peak power demand in distribution networks, but also the tariff plans of EV charging service. The uncertain upstream electricity price considerably complicates the issue regarding how to achieve specific economic goals for distributi...

A store-on grid scheme model is proposed to facilitate grid-tied rooftop solar photovoltaic (PV) systems implementation in developing countries. Using Uganda as a case study, the proposed model’s costs analysis results were compared to time of use rating model for energy consumption results of an industry by considering solar PV system performance...

Electric vehicles (EVs) are one of a prominent solution for the sustainability issues needing dire attention like global warming, depleting fossil fuel reserves, and greenhouse gas (GHG) emissions. Conversely, EVs are shown to emit higher emissions (measured from source to tailpipe) for the fossil fuel-based countries, which necessitates renewable...

Dear Colleagues, We hope you are doing well. /Electronics/ receives its new Impact Factor this year. It increases to 2.412, ranking 125/266 (Q2) in 'Engineering, Electrical & Electronic' according to JCR report 2020. Dr. Ramon Zamora (Auckland University of Technology), Dr. Jian Shi (University of Houston) and Dr. Eng. Muhammad Abdillah (Universit...

This paper investigates thermal overloading, voltage dips and insulation failure across a distribution transformer (DT), under residential and battery electric vehicle (BEV) loadings. The objective of this paper is to discuss the charging impact of BEVs on voltage across consumer-service points, as well as across the life of paper insulation under...

Sustainable livelihoods approach is progressively being applied in feasibility assessment for implementation of alternative energy technologies in developing countries. In this study, an evaluation model for assessing the sustainable livelihoods capitals, namely, social, natural, financial, physical and human capitals by utilizing interpretive stru...

The continuous growth of the number of electric vehicles (EVs) poses great challenges to distribution networks. Intermittent and stochastic EV access detrimentally affects the security of the power supply. In terms of unplanned events, EV users might dispersedly plug in or out at any available spot instead of ensuring identical distribution across...

A R T I C L E I N F O Keywords: Dynamic thermal rating Critical line spans Optimal sensor placement Non-uniform line segmentation Weather conditions and span topography Line congestion and load shed management A B S T R A C T Dynamic thermal rating (DTR) for an overhead transmission line is a viable and cost-effective technique based on real weathe...

The need to enhance the performance of existing transmission network in line with economic and technical constraints is crucial in a competitive market environment. This paper models the total transfer capacity (TTC) improvement using optimally placed thyristor-controlled series capacitors (TCSC). The system states were evaluated using distributed...

Overhead lines rated under conventional line rating techniques have limited power transfer capacity to avoid congestion and line overloading. Rating and operating them under actual weather and loading conditions with electro-thermally coupled parameters can significantly increase line loadability. As a result, line congestion and overloading can be...

Empirical electrical electrolyser models have proven to be effective in simplifying the analysis of multiple systems involving electrolyser. However, the conventional representation of current as an input of the electrolyser model present challenges for circuits involving power converters specifically in Matlab/Simulink implementations. This work p...

This paper proposes an alternative approach to determination of rooftop area suitable for solar PV deployment by using validated open source tools that require minimal computational know-how. The paper goes ahead to evaluate the feasibility of implementing grid-tied rooftop solar PV systems in the industrial sector in Uganda. For the considered sam...

Due to increasing electric vehicles (EVs) uptakes, power system distribution network will have to accommodate the increased load level for charging EVs. Thus, the importance of a robust power system especially in the distribution network level is indisputable. During the planning or reinforcement stage of distribution networks, it is paramount to h...

Renewable energy utilization for electricity supply has increased significantly. Technology maturity, cost reduction, and environmental friendliness are significant factors that encourage this increase. The expansion of distributed generation is increasing significantly due to the concern of many householders and entrepreneurs in minimizing the ene...

Active power loss of transmission lines in a distribution system has been a frequent concern for a great number of researchers. Various approaches have been proposed to minimize active power loss. In this research, two approaches, optimal placement and sizing of distributed generation (DG) and shunt capacitor, are used to reduce the active power lo...

Overhead line is an important asset for power industries. Rising demand in electricity, environmental concerns and cheaper electricity prices are some important factors behind operating the lines at their maximum potential. Replacing overhead lines and/or constructing new lines are not only expensive but also at the same time raise environmental co...

This paper discusses a MATLAB/Simulink/Simscape power system implementation of an alkaline electrolyser directly coupled to a photovoltaic module. Meteorological average daily irradiance and temperature data for a typical summer and winter day in Auckland, New Zealand, is used in a 15-hour simulation duration to show characteristic responses of the...

Networked microgrid can operate in different possible configurations including: islanded microgrid, a grid-connected microgrid without a tie-line converter, a grid-connected microgrid with a tie-line converter, and networked microgrids. These possible alternative configurations and intermittent renewable energy offer challenges in designing control...

This paper presents a Multi-Agent System (MAS) to model and enable an active power management in a multiple microgrids system consisting of batteries, photovoltaic and diesel micro sources in islanded or grid-connected operation. The multi-Agent system was developed in JADE (Java Agent DEvelopment Framework), a Foundation for Intelligent Physical A...

Fuel cell–based power units have increasingly become an attractive option to provide clean and efficient electricity in certain niche applications. This paper discusses the characteristics of a proton exchange membrane (PEM) fuel cell for a battery extender auxiliary power unit and explains the steps of the design process. A two-leg converter topol...

This paper discusses energy management and control algorithms of microgrid with energy storage. Specific management framework within microgrid presented here includes: a) help prioritizing the renewable energy sources (RES) to provide power to local loads, b) manage battery to avoid deep-discharging and overcharging, c) maintain dc link voltage at...

Microgrids with renewable distributed generation and energy storage offer sustainable energy solutions. To maintain the availability of energy to the connected loads, considering priority and to interrupt the smallest portion of the microgrid under any abnormal conditions, reconfiguration is critical to restore service to a section or to meet some...

This paper presents a multi-agent system for realtime operation of simulated microgrid using the Smart-Grid Test Bed at Washington State University. The multi-agent system (MAS) was developed in JADE (Java Agent DEvelopment Framework) which is a Foundation for Intelligent Physical Agents (FIPA) compliant open source multi-agent platform. The propos...

The real time modeling and simulation of smart grid behavior under the disturbance helps in the analysis and planning of system in order to minimize the possible damage. Real time modeling and simulations with hardware in the loop capabilities allows testing the smart grid control algorithms and new equipments. This chapter addresses two aspects o...

Reconfiguration is a control action including topology changes, load/ generation shedding and other measures to redirect power flow to the remaining unaffected loads in a microgrid. In this paper, genetic algorithm (GA) and graph theory based methodologies were used to reconfigure a network, satisfying the operational requirements and priorities of...

Penetration of distributed generation (DG) has significantly increased over the last few decades. Several states in USA have set their own target to meet significant percentage of DG penetration over the years. These requirements will have impacts on grid reliability and operational requirements given inherent intermittency for some of the DG. Ener...

The interest on microgrid has increased significantly triggered by the increasing demand of reliable, secure, efficient, clean, and sustainable electricity. More research and implementation of microgrid will be conducted in order to improve the maturity of microgrid technology. Among different aspects of microgrid, this paper focuses on controls of...