Hector Chavez

University of Santiago, Chile | USACH · Departamento de Ingeniería Eléctrica

The integration of power electronics-interconnected generation systems to the grid has fostered a significant number of concerns on power system operations, particularly on the displacement of synchronous generators that leads to a reduction in the grid’s overall inertia and frequency response. These concerns have raised a significant amount of sta...

This paper focuses on a comprehensive stability study of a two-area power system with wind power integration and synthetic inertia control in each area, considering the effects of varying the interconnection link. Normally, synthetic inertia proposals are analyzed in one-area systems, in which stability is tested without considering transmission sy...

The continued use of energy sources based on fossil fuels has various repercussions for the environment. These repercussions are being minimized through the use of renewable energy supplies and new techniques to decarbonize the global energy matrix. For many years, hydrogen has been one of the most used gases in all kinds of industry, and now it is...

This technical document summarizes recent advancements on spatio-temporal data-driven and machine learning methods for static and dynamic security assessment, and their particular use cases. It is a collective effort of different research groups with the aim of providing transmission system operators (TSOs) with innovative tools and ideas for their...

Frequency‐arresting (FA) adequacy has received an increasing attention in operation of power systems with intermittent, electronically connected wind and sfolar generation. Presence of high penetration of renewable energy leads to reduced amount of inertia in the power system and the need for more sustainable market design. This paper addresses the...

The current need for power-system control-room operational tools to increase real-time situational awareness has led to various proposals on data analytics algorithms to obtain operational information from SCADA and PMU power system networks. Most of the proposals are implemented in simulation, with reduced practical significance for system operato...

The reduction in system inertia under the penetration of power electronic-interfaced generation has fostered various proposals on wind synthetic inertia. Several works in the state of the art propose control strategies to optimize synthetic inertia performance; however, most of the performance metrics indirectly represent frequency control adequacy...

Solid-state transformers (SSTs) are becoming an important solution to control active distribution systems. Their significant flexibility in comparison with traditional magnetic transformers is essential to ensure power quality and protection coordination at the distribution level in scenarios of large penetration of distributed energy resources suc...

Nowadays, transmission system operators require higher degree of observability in real-time to gain situational awareness and improve the decision-making process to guarantee a safe and reliable operation. Digitalization of energy systems allows utilities to monitor the system dynamic performance in real-time at fast time scales. The use of such te...

It is normally accepted that Battery Energy Storage Systems improve frequency regulation by providing fast response to the Automatic Generation Control. However, currently available control strategies may lead to early Energy Storage Systems aging given that Automatic Generation Control requirements are increasing due to zero carbon power generatio...

The integration of the large-scale photovoltaic systems has experienced significant growth, which is similarly expected to occur with small-scale photovoltaic systems. Since small-scale systems must be simple in cost-effective components, control strategies must be implemented in low complexity circuits. However, current maximum power point trackin...

This paper deals with observer design for the class of discrete time-varying descriptor systems. In particular, it is assumed that the dynamical system matrix is a function of time-varying parameters that are not precisely known. For this class of system, a Linear Matrix Inequality (LMI) based approach is proposed to the design of complete state ob...

Distribution customers are exposed to various tariff mechanisms from which they must select one that minimizes the electricity bill. Also, distributed generation (mainly Solar Photovoltaic) and distributed storage (mainly electro-chemical batteries) have arisen as an alternative to reduce electric bills. In general, the problem of selecting a speci...

Moving towards low-carbon electricity systems through the massive deployment of renewable energy sources (RES) presents a unique opportunity to combat climate change, but it also poses enormous technical challenges, especially from a frequency viewpoint. To ensure a secure RES integration in terms of frequency stability, system operators worldwide...

In a scenario where distributed generation infrastructure is increasing, the impact of that integration on electricity tariffs has captured particular attention. As the distribution sector is mainly regulated, tariff systems are defined by the authority. Then, tariffs must be simple, so the methodology, criteria, and procedures can be made public t...

Future plans for integration of large nonsynchronous generation and the expansion of the power system in the Nordic countries are a concern to transmission system operators (TSOs) due to the common interconnections and electricity exchanges among these operative areas. The expected reduction in the inertia anticipates an alteration of the frequency...

The modular multilevel matrix converter has been proposed as a suitable option for high power applications such as flexible AC transmission systems. Among flexible AC transmission systems, the unified power flow controller stands out as the most versatile device. However, the application of the modular multilevel matrix converter has not been thoro...

District heating networks are commonly addressed in the literature as one of the most effective solutions for decreasing the greenhouse gas emissions from the building sector. These systems require high investments which are returned through the heat sales. Due to the changed climate conditions and building renovation policies, heat demand in the f...

This paper presents a methodology to represent ocean wave power generation based on real data observation for significant wave height (SWH or H s ) and wave period (WP or T). This technique is based on a hybrid model, which considers Fourier series and stochastic differential equations, allowing a continuous time representation of the random change...

This paper discusses the application of the Modular Multilevel Matrix Converter (M 3 C) to interface Multi-MW Wind Turbines. The modelling and control systems required for this application are analysed and discussed. A Vector Control Strategy based on nested controllers is proposed to provide decoupled operation of the converter, maximum power poin...

The two largest interconections in Chile (SIC and SING) are about to become interconnected. As power balance is a concern in the operation of a power system, it is important to understand the operation of AGC while systems become interconected. In this sense, the performance of the AGC systems after the interconection may change, and the new operat...

The global initiatives to achieve cleaner ways to generate electricity have motivated non-dispatchable generation to play a major role in the operation of electric power systems. However, this kind of generation along with its variability have increased the need for better control systems to achieve a constant balance between generation and consump...

Various formulations have consider the compliance of control performance standards into account. In terms of secondary frequency control, it is necessary to perform second-by-second, several moths long simulations of system frequency that most commercial software cannot perform. This paper presents a model framework to simulate frequency control dy...

This paper generalizes previous work on automatic generation control (AGC) gain in a single balancing authority system. In previous work, a control performance standard 1 (CPS1)-compliant AGC gain for a single balancing authority interconnection was proposed, assuming that frequency response can be decoupled from AGC dynamics by widening governor d...

The integration of wind power has imposed new requirements for regulation reserves. For ensuring adequate regulation reserves, wind power variability and uncertainty must be estimated, and system frequency must comply with frequency performance standards. This work determines regulation capacity and ramping capability requirements as a function of...

The integration of wind power (WP) into power systems has led to concerns on the adequacy of primary frequency control. Such concerns have currently arisen in interconnections with high penetration of WP and may appear in other systems where high penetration of WP is planned. This paper proposes a method for predicting the level of WP penetration t...

Non-conventional renewable energies are becoming a significant source of generation. This paper is about the integration of Wind Power (WP) into grid, which has led to a revision of the adequacy of primary frequency control (PFC). Here, a method to identify the overall primary frequency responce on system is applied, based on an empirical model val...

This paper generalizes previous work on automatic generation control (AGC) gain in a single balancing authority system. In previous work, a control performance standard 1 (CPS1)-compliant AGC gain for a single balancing authority interconnection was proposed, assuming that frequency response can be decoupled from AGC dynamics by widening governor d...

The integration of wind power has imposed new requirements for regulation reserves. For ensuring adequate regulation reserves, wind power variability and uncertainty must be estimated, and system frequency must comply with frequency performance standards. This work determines regulation capacity and ramping capability requirements as a function of...

The integration of non-dispatchable generation has led to a change in the dynamics of primary frequency response. This change, mostly driven by the limited contribution of non-dispatchable generation to both total system inertia and governor response, may deteriorate the performance of current practices for determining primary reserves to the exten...

The significant penetration of wind generation in power grids has raised new challenges in operational and planning decisions of power systems. Wind turbine units almost always include power converters decoupling the frequency dynamics of the wind power generators from that of the grid. This decoupling causes a reduction in total system inertia, af...

form only given. The significant expansion of wind power capacity in the Electric Reliability Council of Texas (ERCOT) will increase the amount of ancillary services (AS) necessary to maintain ERCOT system frequency targets. This paper analyzes ERCOT regulation adequacy from a simplifed dynamical model of ERCOT validated by empirical data. The mode...

The contribution of non-dispatchable, renewable generation to both total grid inertia and grid frequency response is significantly lesser than that of dispatchable, thermal generation. In large non-dispatchable generation penetration scenarios, the effect of inertia and frequency response diminution on primary frequency control reserves adequacy wi...