Hot Swap Research Articles

Heterogeneous Multi-Robot Collaboration for Coverage Path Planning in Partially Known Dynamic Environments

This research presents a cooperation strategy for a heterogeneous group of robots that comprises two Unmanned Aerial Vehicles (UAVs) and one Unmanned Ground Vehicles (UGVs) to perform tasks in dynamic scenarios. This paper defines specific roles for the UAVs and UGV within the framework to address challenges like partially known terrains and dynamic obstacles. The UAVs are focused on aerial inspections and mapping, while UGV conducts ground-level inspections. In addition, the UAVs can return and land at the UGV base, in case of a low battery level, to perform hot swapping so as not to interrupt the inspection process. This research mainly emphasizes developing a robust Coverage Path Planning (CPP) algorithm that dynamically adapts paths to avoid collisions and ensure efficient coverage. The Wavefront algorithm was selected for the two-dimensional offline CPP. All robots must follow a predefined path generated by the offline CPP. The study also integrates advanced technologies like Neural Networks (NN) and Deep Reinforcement Learning (DRL) for adaptive path planning for both robots to enable real-time responses to dynamic obstacles. Extensive simulations using a Robot Operating System (ROS) and Gazebo platforms were conducted to validate the approach considering specific real-world situations, that is, an electrical substation, in order to demonstrate its functionality in addressing challenges in dynamic environments and advancing the field of autonomous robots.

A Distributed Control Method With Seamless Hot Swap Capability for Generic DC Microgrids

A Distributed Control Method With Seamless Hot Swap Capability for Generic DC Microgrids

A hardware and software complex for adaptive monitoring of a limited ecosystem with a cloud segment

In modern conditions, as Ukraine faces numerous challenges in the fields of ecology and security, the development of comprehensive monitoring methods for restricted ecosystems becomes increasingly relevant. The research resulted in the creation of a decomposed model for data movement within this closed system, featuring a modular structure. This is a crucial aspect for the rapid expansion of the existing system's functionality and the hot swapping of complex components. Upon reviewing the issue, it was determined that the methods of adaptive monitoring research for restricted ecosystems using special services on the potentially dangerous objects and objects of critical infrastructure were not sufficiently effective. The authors proposed, modeled, and developed a new hardware-software complex that enables the implementation of a set of tools specifically tailored for monitoring in areas of anthropogenic pollution. The optimal set of sensors for the sensor module was enhanced. A unique superposition of local and cloud solutions for data accumulation, analysis, processing, and visualization is recommended for further work in this and related fields. The integration of a new solution stack in the sub-gigahertz range, with the extension of the spectrum, distinguishes the project with resilience, while the Advanced Encryption Standard adaptation implements mid-attack protection. The expected effect of implementing the multisensory system lies in the early detection of emergency situation factors, forecasting, and decision-making regarding the elimination of the arising danger, as well as the prompt involvement of relevant units of the State Emergency Service of Ukraine and other government structures. The simple implementation mechanism of the system ensures scalability and the quick replacement of key elements.

Current Control of Battery Pack Modules in Parallel Connection According to SoC

Electric vehicles, especially cars, have been in the spotlight for some time now. In the focus of environmentalists, engineers, users, media, etc. With the growth and advancement of the market for such vehicles, other electric vehicles are also focussing on. One of such vehicles is boats, particularly smaller boats up to 8–10 meters in length. Of course, the biggest problem here is charging. The general idea is to use battery modules that can be easily carried and enable hot swapping. This paper investigates scenarios and simulations of the control system for hot swapping of the battery module. Simulations of connection of two and three battery modules to parallel operation and current control are presented in this paper, as well as applied control rules.

Analysis of Performance Improvement of Real-time Internet of Things Application Data Processing in the Movie Industry Platform.

The goal of this study is to plan and develop complete strategies to improve the performance of film industry. The primary objectives of this study are to investigate a dataset generated by a IoT application and the nature of the data forms obtained, the speed of the data arriving rate, and the required query response time and to list the issues that the current film industry faces when attempting to handle IoT applications in real time. Finally, in film industry platforms, high performance with varied stream circulation levels of real-time IoT application information was realized. In this study, we proposed three alternative methods on top of the Storm platform, nicknamed Re-Storm, to improve the performance of IoT application data. Three different proposed strategies are (1) data stream graph optimization framework, (2) energy-efficient self-scheduling strategy, and (3) real-time data stream computing with memory DVFS. The work proposed a methodology for dealing with heterogeneous traffic-aware incoming rate of data streams Re-Storm at multiple traffic points, resulting in a short response time and great energy efficiency. It is divided into three parts, the first of which is a scientific model for fast response time and great energy efficiency. The distribution of resources is then considered using DVFS approaches, and successful optimum association methods are shown. Third is self-allocation of worker nodes towards optimizing DSG using hot swapping and making the span minimization technique. Furthermore, the testing findings suggest that Re-Storm outperforms Storm by 20–30% for real-time streaming data of IoT applications. This research focuses on high energy efficiency, short reaction time, and managing data stream traffic arrival rate. A model for a specific phase of data coming via IoT and real-time computing devices was built on top of the Storm platform. There is no need to change any software approach or hardware component in this design, but only merely add an energy-efficient and traffic-aware algorithm. The design and development of this algorithm take into account all of the needs of the data produced by IoT applications. It is an open-source platform with less prerequisites for addressing a more sophisticated big data challenge.

Estimation of the Hot Swap Circulation Current of a Multiple Parallel Lithium Battery System with an Artificial Neural Network Model

Battery applications, such as electric vehicles, electric propulsion ships, and energy storage systems, are developing rapidly, and battery management issues are gaining attention. In this application field, a battery system with a high capacity and high power in which numerous battery cells are connected in series and parallel is used. Therefore, research on a battery management system (BMS) to which various algorithms are applied for efficient use and safe operation of batteries is being conducted. In general, maintenance/replacement of multi-series/multiple parallel battery systems is only possible when there is no load current, or the entire system is shut down. However, if the circulating current generated by the voltage difference between the newly added battery and the existing battery pack is less than the allowable current of the system, the new battery can be connected while the system is running, which is called hot swapping. The circulating current generated during the hot-swap operation is determined by the battery’s state of charge (SOC), the parallel configuration of the battery system, temperature, aging, operating point, and differences in the load current. Therefore, since there is a limit to formulating a circulating current that changes in size according to these various conditions, this paper presents a circulating current estimation method, using an artificial neural network (ANN). The ANN model for estimating the hot-swap circulating current is designed for a 1S4P lithium battery pack system, consisting of one series and four parallel cells. The circulating current of the ANN model proposed in this paper is experimentally verified to be able to estimate the actual value within a 6% error range.

An implementation of module management controller for MicroTCA data processing system

On the basis of full compatibility with advanced telecommunications computing architecture (ATCA) standard, micro telecommunications computing architecture (MicroTCA) standard has a evident advantage over ATCA in terms of space, cost and scalability. The MicroTCA standard has become a popular platform in high energy physics. For the advanced mezzanine card (AMC) installed in the MicroTCA chassis, module management controller (MMC) is a prerequisite to fulfill its function. Although there are many MMC solutions, most of their firmware work in polling mode and rarely use the real-time operating system (RTOS). In order to overcome the lack of real-time performance in polling MMC solution, the novel firmware is developed based on FreeRTOS, which is an open source real-time operating system. This firmware implements the basic functions of MMC, such as hot swap, power management, firmware upgrade, and adds the feature of serial command debugging. To verify the difference in real-time performance between the FreeRTOS and the polling solutions, the interrupt reaction time test is carried out on both solutions. The test shows that the average interrupt reaction time of the FreeRTOS solution is about 300 ms shorter than that of the polling method. This result proves that the FreeRTOS-based solution can significantly improve the real-time performance of transaction processing.

Grid-Forming Converters Control Based on the Reactive Power Synchronization Method for Renewable Power Plants

The massive penetration of renewable energy sources in electrical systems has been displacing synchronous generators (SGs) from conventional power plants in the last few years. Renewable generation plants are usually connected to power grids through electronic power converters, which cannot provide the same power generation services as SGs due to their mode of operation. Recently, different concepts have been proposed for electronic converter control in an attempt to emulate the performance of SGs, resulting in the so-called grid-forming converters (GFCs). This paper proposes a new GFC control strategy based on the reactive power synchronization (RPS) method, which decouples the synchronizing power and the active power control of renewable generation source to which a converter is connected. For this purpose, this study assesses three power sources: batteries, photovoltaic (PV) plants, and full-converter wind turbines. Moreover, the study proposes models and controls for each of these sources, whose dynamics exert a decisive influence on the grid services provided by renewable energy plants. Thereafter, the study proposes a GFC–RPS control scheme and verifies its effectiveness in different applications; for example, inertial response, which provides power immediately through a fast frequency response after a grid has experienced a load variation. Unlike storage systems and wind turbines, PV plants can only render these services if they are not operating at maximum power. Further, the study validates the GFC–RPS control strategy for regulating AC voltage at the output terminals of a converter. Finally, the paper assesses GFC hot swapping during the transition from a grid-connected to an isolated-operation mode while feeding a dynamic load. Results revealed that both the voltage and frequency remain stable, thereby demonstrating that the proposed GFC–RPS control indeed acts as a true voltage source and emulates the behavior of a conventional SG.

A General Fault-Tolerant Operation Strategy Under Switch Fault for Modular Series–Parallel DC–DC Converter

Modular series–parallel dc–dc converters (MSPDDCs) are good options in high-power high-voltage applications. A reliable operation should be a top concern in such critical situations. In this article, a general fault-tolerant method for switch fault is proposed for MSPDDC, including fast fault diagnosis (FD) and postfault reconfiguration. The FD is achieved using the relationship between output inductor voltage and gate driver signal in each module. The inductor voltage is acquired by adding a small auxiliary winding into the magnetic core, and no expensive sensors are introduced. A general and low-cost hardware circuit is designed to locate faulty module in a very short time. The reconfiguration process for four structures is then systematically presented. Through a careful timing sequence design, a fast and smooth hot swap is realized, and its impact on the output side and the other healthy modules is minimized. The principle of FD and reconfiguration, hardware implementation, and experimental verification are given in this article.

Managing Inrush Current using Hot Swap and OR-ing FET

Critical, high availability systems will always rely on redundant power for continuous operation when the default power fails or becomes unavailable. When the back-up system kicks in, there will be a huge inrush current depending on load. The consequences of inrush current can be reduction of output voltage, tripping of protective devices, damage to sensitive devices either on at the load or on the back-up system itself and eventually system failure. This dissertation studies the effects of inrush current on an already existing Redundant Power Distribution System (RPDS). A review of existing technique to control inrush current is presented. A new solution has been implemented on the Redundant Power Distribution System such that the functionality of overall system is preserved. Finally, performance of existing solution on RPDS and new solution are compared.

A Sensor Web Prototype for Cabled Seafloor Observatories in the East China Sea

Seafloor observatories enable continuous power supply and real-time bidirectional data transmission, which marks a new way for marine environment monitoring. As in situ observation produces massive data in a constant way, the research involved with data acquisition, data transmission, data analysis, and user-oriented data application is vital to the close-loop operations of seafloor observatories. In this paper, we design and implement a sensor web prototype (ESOSW) to resolve seafloor observatory information processing in a plug-and-play way. A sensor web architecture is first introduced, which is information-oriented and structured into four layers enabling bidirectional information flow of observation data and control commands. Based on the layered architecture, the GOE Control Method and the Hot Swapping Interpretation Method are proposed as the plug-and-play mechanism for sensor control and data processing of seafloor observatory networks. ESOSW was thus implemented with the remote-control system, the data management system, and the real-time monitoring system, supporting managed sensor control and on-demand measurement. ESOSW was tested for plug-and-play enablement through a series of trials and was put into service for the East China Sea Seafloor Observation System. The experiment shows that the sensor web prototype design and implementation are feasible and could be a general reference to related seafloor observatory networks.

PCIe Hot-Plug Support Standardization Challenges in ATCA

Throughout the last decade, the Advanced Telecommunications Computing Architecture (ATCA) solidified its position as one of the main switched-based crate standards for advanced Physics instrumentation, offering not only highly performant characteristics in data throughput, channel density or power supply/dissipation capabilities, but also special features for high availability (HA), required for latest and upcoming large-scale endeavours, as is the case of ITER. Hot Swap is one of the main HA features in ATCA, allowing for Boards to be replaced in a crate (Shelf), without powering off the whole system. Platforms using the Peripheral Component Interconnect Express (PCIe) protocol on the Fabric Interface must be complemented, at the software level, with the PCIe Hot Plug native feature, currently not specified for the ATCA form-factor. From a customised Hot Plug support implementation for ATCA Node Boards, the paper presents an implementation extension for Hub Boards, allowing Hot Plug of PCIe switching devices, without causing bus enumeration problems. This paper further addresses the main issues concerning an eventual standardization of PCIe Hot Plug support in ATCA, such as the implementability of Hot Plug Elements and the generation and management of Hot Plug Events, aiming to stimulate the discussion within the PICMG community towards a long overdue standardized solution for Hot Plug in ATCA.

A Tunable Power Sharing Control Scheme for the Output-Series DAB DC–DC System With Independent or Common Input Terminals

To connect the low voltage energy storage source equipment and the medium voltage dc (MVdc) bus, the output-series dual-active-bridge (OS-DAB) dc–dc converter system with independent or common input terminals becomes a promising option. For the OS-DAB dc–dc converter system, this letter proposes a simple tunable power sharing control (TPSC) strategy to maintain the voltage of MVdc bus, manage power sharing ratio for each energy storage system. The proposed strategy allows energy storage equipment hot swap as well as converter system black start. Experimental results verify the analysis in this letter and the excellent performance of proposed TPSC strategy.

The Comprehensive Circuit-Parameter Estimating Strategies for Output-Parallel Dual-Active-Bridge DC–DC Converters With Tunable Power Sharing Control

The centralized output-parallel dual-active-bridge (OP-DAB) dc-dc system is a promising candidate for achieving isolated dc-dc energy conversion with large current and power rating. To implement the flexible power sharing performance of the OP-DAB dc-dc converter, a simple tunable power sharing (TPS) strategy is proposed with the single-phase-shift method in this article. Based on the TPS strategy, the excellent dynamic performance under disturbances of input voltage for each module and load resistor can be provided. However, inaccurate circuit-parameter information always damages the power sharing performance among different DAB converters. Therefore, the comprehensive circuit-parameter estimating schemes proposed for different conditions of the OP-DAB dc-dc system including the start-up process, the working process and plugging-in a new DAB dc-dc converter, respectively. Moreover, the hot swap (plug-in and plug-out) control methods of the DAB converter without large influence on output voltage is also discussed in detail. Experimental results are obtained to verify the analysis in this article and the excellent performance of the proposed methods.

Series‐type charger with output voltage automatically regulated and hot swap

SummarySince the traditional series‐type charger has no function of hot swap, a new series‐type charger with hot swap is presented herein. In this study, hot‐swap battery and stopping charging battery are achieved by floating voltage detection and battery bypass detection. Furthermore, by means of controlling the voltage across the collector of the bipolar junction transistor (BJT) and the ground, the output voltage of the DC–DC converter can be automatically adjusted. Accordingly, the BJT can always work under the active region with a designed constant voltage across it for any number of batteries in the steady state, reducing undesired conduction loss. Also, one constant current control circuit is utilized, which is connected in series with the voltage and bypass detectors. Above all, unlike the traditional series‐type charger with the active equalizer, there is no energy transferred among batteries in the proposed charger. Finally, the proposed series‐type charger with four battery channels is designed and applied to charging 18650 Li‐ion batteries. Via some experimental results, the effectiveness of the proposed charger can be verified.

Taking advantage of the intercommunication features of IPMCs in ATCA CDAQ systems

The PCI Industrial Computer Manufacturers Group (PICMG) 3.x AdvancedTCA Base Specification and Intelligent Platform Management Interface (IPMI) standards specify a modular system for Control and Data Acquisition (CDAQ) where the boards can communicate through the Intelligent Platform Management Bus-0 (IPMB-0).CDAQ systems applied to large physics experiments like ITER, are designed, among other features, for High-Availability (HA). A CDAQ system based on the PICMG 3.x AdvancedTCA Base Specification and IPMI standards grants these features. One of the key functions of the HA is the hot swapping possibility of the CDAQ system elements which is granted by those standards. An Advanced Telecommunications Computers Architecture (ATCA) CDAQ system can be designed implementing the Peripheral Component Interconnect Express (PCIe) standard communication protocol in their fabric lines. Despite the fact that this protocol has its own rules for hot swapping, defined as hot-plug, ATCA and PCIe standards are not entirely compatible in what concerns this aspect.Instituto de Plasmas e Fusão Nuclear (IPFN) has developed and implemented a CDAQ system using the ATCA and PCIe standards.This paper describes the software architecture and functions implemented in the microcontroller of the Intelligent Platform Management Controller (IPMC) of the ATCA boards in order to render those standards compatible in what concerns hot-swap and hot-plug processes as an example of the possibilities that can be achieved taking advantage of the intercommunication features of IPMCs through the Intelligent Platform Management Bus-0 (IPMB-0).

Parallel Driven Power Supply with Low Cost Hot Swap Controller for Server

Parallel Driven Power Supply with Low Cost Hot Swap Controller for Server

Outrush Current Control by Hot Swap Controller for Battery Protection in Electrical Vehicle

This paper focuses on problem-solving for large outrush current from DC power supply to capacitive load in an electric vehicle. This outrush current occurs during a pre-charge state of traction battery to cause high spike peak and consequently damage the main switching contact and the battery cell. In this paper the current control to gradually increase the outrush current by hot swap controller was proposed. The responses of the proposed control and the classical control were compared and investigated. With the proposed control technique, the impact of harmful outrush current can be reduced. As a result, the hot swap controller gave satisfactory responses and provided good stability.

Interfacing ATCA Hot-Swap with PCIe Hot-Plug for high-availability instrumentation in critical systems

High availability (HA) is a key requirement of next generation Fusion devices, targeting steady-state operation. HA is demanded in mission-critical systems, as is the case of experimental Fusion devices and future Fusion power plants, where safety of people, environment, infrastructure and investment is primordial. IPFN (Institute of Plasma and Nuclear Fusion, Lisbon − Portugal) developed control and data acquisition instrumentation based on the Advanced Telecommunications Computing Architecture (ATCA), composed of digitizing (nodes) and switching (hub) boards, which establish a PCIe data network through ATCA’s backplane Fabric Interface, connecting to an external host computer. The ATCA standard was selected to achieve a high level of availability, as it is a modular platform of Field Replaceable Units (FRU) used with several redundancy resources. Its mandatory hardware platform management, includes a “Hot Swap” mechanism, which allows FRU insertion and extraction without having to power off the system. From the host/software perspective, ATCA nodes and hubs correspond to PCIe endpoint and switch devices. The PCIe standard specifies a Hot-Plug procedure for device add and removal for adapter cards only, whereas for other form-factors the Hot-Plug mechanism is implementation-dependent and should be defined by the form-factor itself. Although ATCA has an extension for PCIe on Fabric Interface, it does not define Hot-Plug procedures. From an initial Hot-Plug solution developed for IPFN’s platform, the paper attempts to establish a relationship between these specifications, which could help to standardize PCIe Hot-Plug implementation for the ATCA form-factor, fostering the development of instrumentation with HA requirements.

Development of High-Availability ATCA/PCIe Data Acquisition Instrumentation

Latest Fusion energy experiments envisage a quasi-continuous operation regime. In consequence, the largest experimental devices, currently in development, specify high-availability (HA) requirements for the whole plant infrastructure. Highly available systems operate seamlessly in the case of component failure, ensuring safety of equipment, people, environment and investment. Control and Data Acquisition (C&DA) systems for Fusion diagnostics are considered mission-critical and require high degrees of availability. IPFN developed a C&DA system for fast control of advanced Fusion devices, targeting HA. The hardware platform is based on in-house developed Advanced Telecommunication Computing Architecture (ATCA) instrumentation modules–digitizing and data switch blades using PCI Express (PCIe) over the ATCA backplane Fabric Channel Interface, connecting to an external PCIe host computer. At the hardware management level, the system architecture takes advantage of ATCA’s HA characteristics, such as its redundant hardware components, redundant backplane topologies and Field Replaceable Unit (FRU) “Hot Swap”. At the software level, PCIe supports “Hot Plug” graceful device insertion and removal. The implementation of PCIe Hot Plug for the ATCA form-factor is one of the major tasks involved and a solution for such implementation was also developed. The paper describes how IPFN C&DA system can be setup to take advantage of both ATCA and PCIe features to perform with the desired degree of availability, by implementing fail-over mechanisms based on the use of redundancy, thus being suitable for advanced C&DA systems in Fusion.