Transfer Switch Research Articles

AUTOMATIC TRANSFER SWITCH UNTUK RUMAH TINGGAL SEDERHANA BERBASIS ARDUINO NANO

Automatic Transfer Switch (ATS) is a device that can move the main power source to a backup power source automatically and quickly when the main power source experiences a disturbance or cut-off of supply to the load. In this study, ATS was designed based on the Arduino Nano microcontroller as an automatic control that works based on voltage readings. Using the Arduino Nano microcontroller can facilitate the process of making tools and minimize the use of components. This ATS uses the PZEM-004T voltage sensor module. The voltage sensor module functions to detect and measure the value of the PLN voltage. From the test results, it was found that the time lag between the PLN supply being cut off until the generator was turned on and ready to load was an average of 2.76 seconds. Meanwhile, the time lag when the PLN supply turns on again until the generator supply is cut off and the load supply is again served by PLN is an average of 1.74 seconds. All working status of this ATS panel can be displayed on the LCD indicator, indicator light and analog voltmeter.

Design of a Partially Grid-Connected Photovoltaic Microgrid Using IoT Technology

This study describes the design and control algorithms of an IoT-connected photovoltaic microgrid operating in a partially grid-connected mode. The proposed architecture and control design aim to connect or disconnect non-critical loads between the microgrid and utility grid. Different components of the microgrid, such as photovoltaic arrays, energy storage elements, inverters, solid-state transfer switches, smart-meters, and communication networks were modeled and simulated. The communication between smart meters and the microgrid controller is designed using LoRa communication protocol for the control and monitoring of loads in residential buildings. An IoT-enabled smart meter has been designed using ZigBee communication protocol to evaluate data transmission requirements in the microgrid. The loads were managed by a proposed under-voltage load-shedding algorithm that selects suitable loads to be disconnected from the microgrid and transferred to the utility grid. The simulation results showed that the duty cycle of LoRa and its bit rate can handle the communication requirements in the proposed PV microgrid architecture.

Penerapan Sistem Daya Cadangan Untuk Lemari Vaksin Menggunakan PLTS Pada Puskesmas Sindangbarang Bogor

The temperature stability of the vaccine needs to be designed in such a way as to maintain its quality. Where vaccines are generally placed in a special refrigerator with an internal temperature of around +20C - +80C. The condition of the electricity network in the Bogor area, which sometimes goes out for a long time can cause electricity to not be supplied for vaccine refrigerators. For a long period of time, this condition can cause damage to the vaccine so that it cannot be given to toddlers. This activity is the application of technology that is very useful for the people of the Bogor, especially for the Sindangbarang Health Center in Bogor related to the design of power reserves, especially for vaccine refrigerators. This power backup system uses various equipment with appropriate technology such as Automatic Transfer Switch (ATS), solar panels, inverters, batteries, solar charge controllers and other supporting equipment. This PKM program has a focus on managing backup power systems in vaccine cabinets using solar power plants

Analysis of Display Cabinet Design with Commissioning Test for Fresh Sea Food

This research is a design of a display cabinet cooling system with integrated energy from PLN electricity and solar power. This equipment is used for displaying marine fish and other fresh sea food in restaurants or cafes in support of Balinese culinary specialties, namely grilled fish and seafood which are very well known and can be a very extraordinary carrying capacity for Bali tourism. This cooling system is designed to be able to maintain the temperature of the cooling room (cabin) up to -5 oC. This is in accordance with the standards for storing fresh sea fish and sea food in a temperature range of -2oC to 2oC, where fish and sea food are still in a very fresh condition for an average of 1 week. Other standards to maintain product freshness also require room humidity between RH 90% – RH 95%. Furthermore, data collection on system performance is carried out using the commissioning test method to determine the initial performance achievement of the tool so that its shortcomings can be evaluated which will be developed and corrected in further research. From the research, it is found that the temperature achievement is very good, the solar and PLN integration system with the Automatic Transfer Switch (ATS) control system has also worked well where the switch occurs when the battery charging condition is below 30% or below 10V. However, something that has not been achieved is the humidity in this system, the average relative humidity (RH) is 50% so that the final condition of the product becomes dry on the surface of the fish. This relatively low humidity is due to the fact that it still relies on the humidity increase system by opening the cooler cabin door. In the next development, the right humidifier system will be designed for this display cabinet system.

Optimizing the Use of MPPT in PLTS for Hybrid Systems by Using STS as a Transfer Switch

To save energy nowadays is recommended to switch to renewable energy sources. In Indonesia, solar energy is abundant, so PLTS is made. The supply of PLTS is expected to reach maximum use. However, solar panels have many obstacles such as variations in temperature and sunlight intensity, MPPT systems are needed to find the maximum power point of the solar panels. Unfortunately, in Indonesia, the sunlight of short duration with the ideal irradiation time that can produce electricity from solar panels is 4 to 5 hours per day, so a PLN supply is still needed to support the continuity of the power supply. Because two sources are used, there is a problem where the load needs high continuity during power switching, so STS (Static Transfer Switch) is used for very fast power switching. Simulation results, when using EMR (Electromechanical Relay) the power transfer process takes 50ms or 5 cycles while STS takes 2ms or ¼ cycles. With very fast response to STS, sensitive equipment is kept safe from power quality disturbances such as voltage sag and voltage swell.

Optimization of Phase Determining Method for Automatic Transfer Switch Operation Based on Simulated Annealing

Fast reserve supply input systems significantly increase the reliability of power supply due to the possibility of preserving the technological process in case of emergency situations. The accuracy of determining the phase of the residual voltage on the busbar in process of connecting the power reserve supply provides a way to significantly reduce the starting overcurrents. In this paper, some modifications of the annealing method for determining the phase of the residual voltage on main section of busbar for emergency mode are considered. The obtained simulation results based on MATLAB environment make it possible to carry out a comparative analysis of a number of calculations for phase estimation design of automatic transfer switch operations based on simulated annealing.

Analysis and Experimental Research On Dynamic Characteristics of Operating Mechanism of Fast Vacuum Transfer Switch

The mathematical model of electromagnetic repulsion operating mechanism of fast vacuum transfer switch (FVTS) for 400 V/630 A/12.5 kA dual power supply system is proposed, and two-dimensional rotational symmetry model of electromagnetic field simulation is established in this paper. Taking the repulsion peak value, velocity characteristics and starting time as the design goals, through analysis and comparation of the dynamic characteristics of the double coil and the metal disc repulsion mechanism, the design scheme of the operating mechanism for the FVTS with short stroke and short opening time is realized. Based on the comparative study of simulation and experiment of vacuum transfer switch prototype with fast repulsion mechanism, the 5.5 mm stroke can be completed within 5ms under the operating condition of 320 V capacitor voltage and 8000 μF, which meets the engineering application requirements of fast switching for the sensitive load.

Analyses of Electromagnetic Buffer Characteristics of Operating Mechanism for Fast Vacuum Transfer Switch

The electromagnetic repulsion model of 400 V/630 A/12.5 kA fast vacuum transfer switch (FVTS) is established using finite element method. The speed and characteristics of the contact bounce of the FVTS are taken as constraints, and the objective is to keep the reliable opening of the mechanism with allowable bounce. The deceleration of the fast operating mechanism in the process of opening and closing is realized by applying the reverse electromagnetic repulsion force. Moreover, the simulation results demonstrate that the electromagnetic buffer effect is available, and the allowable bounce opening of the operating mechanism has been obtained. Furthermore, this paper compares the buffering effects of three kinds of conditions, such as no electromagnetic buffering, 110 V electromagnetic buffering and 220 V electromagnetic buffering. It can be found that the electromagnetic buffering is a necessary part of the 400 V FVTS, and the dynamic characteristics are the optimal scheme when the 220 V electromagnetic buffering is applied. Based on the results of simulation, a FVTS experimental prototype is developed to prove the effectiveness of the design scheme.

A low-jitter self-triggered spark-discharge pre-ionization switch: primary research on its breakdown characteristics and working mechanisms

MV pulsed switch plays a key role as the transfer switch in large electromagnetic pulse simulators. To broaden the range of self-triggering time, a novel spark-discharge pre-ionization switch, in which the main gap electric field is superposed at the trigger gap to let the electrons in its spark channel also become initial electrons, is proposed and tested. The design idea is: as electrons in the spark channel of the trigger gap always exist after its breakdown, the injection time of pre-ionization should have a more negligible effect on reducing the switch jitter. The experiment results under pulses with a rise time of ∼100 ns support the above assumptions. When the operating voltage is from ∼300 to ∼800 kV and the self-triggering time is ∼45% to ∼75% of the peak time, the breakdown time delay jitter is less than 2 ns, and the breakdown voltage jitter is smaller than 1.25%. Under specific self-triggering time, the breakdown time delay jitter is less than 1.5 ns, and the breakdown voltage jitter is smaller than 0.8%.

Solid State Switching Control Methods: A Bibliometric Analysis for Future Directions

Recently, the development and controls of solid-state switching have gained significant popularity over the years especially in academic research. The development of control strategies in solid state switching applications to ensure fast switching in a protected distribution system has fueled a great deal of investigation and further developments. Therefore, a critical review and analysis in the field of solid-state switching for distribution systems are provided in this article. The Scopus database is used to compile a list of the most cited published papers in the field of solid-state switching control methods based on the identified criteria. The study explores 120 of the most cited articles emphasizing six keywords such as a solid-state breaker, solid-state transfer switch, static transfer switch, automatic transfer switch, automatic protection switches, and solid-state protection switch. The analysis was conducted using the Scopus database in the fourth week of January 2021. The 120 articles were collected from 24 different journals and 27 different countries. It is reported that 78% of the published papers outline the methodology based on control and test systems whereas 22% of articles are based on review surveys. From that, 73% of articles concentrate on the protection strategy in the system. The main objective of the article is to classify and define the highly cited published articles in the field of solid-state switching control methods as well as to provide direction for future research on fast switching in the distribution system. The analysis also highlights various factors, issues, challenges, and difficulties to identify the existing limitations and research gaps. This review will serve to strengthen the development concepts of solid-state switching control methods towards achieving improved operational performance, energy-saving, economic prosperity, and enhanced power quality. The authors believe that this bibliometric evaluation will allow academic researchers to identify opportunities for growth in the solid-state switching industry.

Mode‐adaptive multifunctional control of the distributed generation‐based AC microgrid for seamless grid synchronisation

This study presents a mode adaptive multifunctional control strategy that avoids the collapse of the microgrid due to the subsequent failure of the generation units and faulty grid. Its control allows the distributed generation-based AC microgrid consisting of a PV panel, wind generation unit and battery energy storage to operate seamlessly during utility connected and outage operating modes. On the occurrence/clearance of the faults, the isolation/reconnection of the microgrid to the utility is ensured via static transfer switches (STSs). The change of mode occurs between the current to voltage control or vice-versa. To ensure high-quality power in both the modes, bias compensated normalised least mean square (BC-NLMS) algorithm is implemented to estimate the total active current component of loads and to improve the power quality of the grid indices. Extended second order generalised integrator-based frequency locked loop (eSOGI-FLL) control avoids frequency and phase oscillations and provides the effective frequency and phase synchronisation. In an islanded operating mode, the enhanced proportional resonant (PR) controller along with eSOGI-FLL regulates the load voltages. The battery energy storage facilitates uninterruptable supply to the critical loads. The efficacy of the microgrid control is illustrated by the simulated as well as experimental results.

Fluorescent Molecular Logic Gates Driven by Temperature and by Protons in Solution and on Solid.

Temperature-driven fluorescent NOT logic is demonstrated by exploiting predissociation in a 1,3,5-trisubstituted Δ2 -pyrazoline on its own and when grafted onto silica microparticles. Related Δ2 -pyrazolines become proton-driven YES and NOT logic gates on the basis of fluorescent photoinduced electron transfer (PET) switches. Additional PASS 1 and YES+PASS 1 logic gates on silica are also demonstrated within the same family. Beside these small-molecule systems, a polymeric molecular thermometer based on a benzofurazan-derivatized N-isopropylacrylamide copolymer is attached to silica to produce temperature-driven fluorescent YES logic.

Mm-Wave Through-Load Element for On-Wafer Measurement Applications

This paper presents an innovative Through-Load element aimed at characterization applications at mm-wave frequencies. The proposed structure can behave as a Through connection or as a 50-Ω load depending on a DC control voltage. Among other potential applications, this system can be used to implement a transfer switch or an attenuator. A demonstrator was fabricated and measured in the STM 55-nm BiCMOS technology. Over a wide bandwidth, from 55 GHz up to 170 GHz, experimental measurements demonstrate a maximum 1.6-dB of insertion loss when behaving as a Through connection and a minimum 14-dB of insertion loss when behaving as a 50-Ω load. In both cases, the return loss is better than 10 dB. The insertion loss at 90 GHz is 0.6 dB for the Through connection and 20 dB for the 50-Ω load connection.

Research on the influencing factors of the switching behavior of Chinese social media users: QQ transfer to WeChat

PurposeThis research takes the transfer behavior of users from Tencent QQ to WeChat as an example to discuss the wider transfer behavior of social media users on the Internet.Design/methodology/approachThis paper collects data through a combination of offline interviews and online questionnaire surveys, and utilizes data analysis tools to construct structural equation modeling (SEM). Using Statistical Product and Service Solutions (SPSS) Statistics 22.0 and Analysis of Moment Structures (AMOS) 22.0 software with SEM, this study was carried out to provide reasonable statistical support for relevant proposed hypotheses based on 368 effective samples acquired through the questionnaire.FindingsThe findings of this study show that subjective norm, transfer experience, social communication, and knowledge acquisition all have significant associations with transfer intention and switching behavior. To be specific, transfer intention exerts a positive association on switching behavior; function setting, privacy protection and personal innovation have a favorable association with transfer intention; transfer cost has a significantly negative relationship with transfer intention and switching behavior; function setting has no important relationship on switching behavior.Originality/valueThe research results provide a reference for improving the viscosity and loyalty of social media users in the new era and resolving the problem of user churn.

A smart post-synthetic route towards [Fe2Co2] molecular capsules with electron transfer and bidirectional switching behaviors

A smart post-synthetic route towards [Fe2Co2] molecular capsules with electron transfer and bidirectional switching behaviors

Influence of Reduced Field Strength on Product Ion Formation in High Kinetic Energy Ion Mobility Spectrometry (HiKE-IMS).

Classical ion mobility spectrometers (IMS) operated at ambient pressure, often use atmospheric pressure chemical ionization (APCI) sources to ionize organic compounds. In APCI, reactant ions ionize neutral analyte molecules via gas-phase ion-molecule reactions. The positively charged reactant ions in purified, dry air are H3O+, NO+, and O2+•. However, the hydration of reactant ions in classical IMS operated at ambient pressure renders ionization of certain analytes difficult. In contrast to classical IMS operated at ambient pressure, High Kinetic Energy Ion Mobility Spectrometers (HiKE-IMS) are operated at a decreased pressure of 10-40 mbar, allowing operation at high reduced electric field strengths of up to 120 Td. At such high reduced field strengths, ions reach high effective temperatures causing collision-induced cluster dissociation of the hydrated gas-phase ions, allowing ionization of nonpolar and low proton affinity analytes. The reactant ion population, consisting of H3O+(H2O)n, NO+(H2O)m, and O2+•(H2O)p with an individual abundance that strongly depends on the reduced field strength, differs from the reactant ion population in IMS operated at ambient pressure, which affects the ionization of analyte molecules. In this work, we investigate the influence of reduced field strength on the product ion formation of aromatic hydrocarbons used as model substances. A HiKE-IMS-MS coupling was used to identify the detected ion species. The results show that the analytes form parent cations via charge transfer with NO+(H2O)m and O2+•(H2O)p depending on ionization energy and protonated parent molecules via proton transfer and ligand switching with H3O+(H2O)n mainly depending on proton affinity.

Tracking interfacial single-molecule pH and binding dynamics via vibrational spectroscopy.

Understanding single-molecule chemical dynamics of surface ligands is of critical importance to reveal their individual pathways and, hence, roles in catalysis, which ensemble measurements cannot see. Here, we use a cascaded nano-optics approach that provides sufficient enhancement to enable direct tracking of chemical trajectories of single surface-bound molecules via vibrational spectroscopy. Atomic protrusions are laser-induced within plasmonic nanojunctions to concentrate light to atomic length scales, optically isolating individual molecules. By stabilizing these atomic sites, we unveil single-molecule deprotonation and binding dynamics under ambient conditions. High-speed field-enhanced spectroscopy allows us to monitor chemical switching of a single carboxylic group between three discrete states. Combining this with theoretical calculation identifies reversible proton transfer dynamics (yielding effective single-molecule pH) and switching between molecule-metal coordination states, where the exact chemical pathway depends on the intitial protonation state. These findings open new domains to explore interfacial single-molecule mechanisms and optical manipulation of their reaction pathways.

Non-Volatile Multiport DC–30 GHz Monolithically Integrated Phase-Change Transfer Switches

This paper reports two configurations of non-volatile multiport transfer switches based on the phase change material (PCM) germanium telluride. The monolithic transfer switches are developed in-house using a custom microfabrication process designed to operate over a wideband dc-30GHz. A C-type switch configuration is presented with two operational states in a highly miniaturized package with the device core area under 0.09mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> . A unique, highly versatile multiport R-type switch configuration is proposed with three operational states that offers improved system flexibility, reducing the number of switches for routing. The R-type switch configuration has a device core periphery under 0.2mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> . The presented devices are compared with the current state-of-the-art switch technologies. The transfer switches exhibit a measured insertion loss of less than 1.5dB, return loss better than 18dB, and +35.5dBm measured power handling capability with switching speed less than 2 μs.

Bi-Directional Power Flow in Switchgear with Static Transfer Switch Applied at Various Renewable Energies

In this study, we describe the development of a plug-in type of switchgear that can control bidirectional power flow. This switchgear system can connect distributed generations such as photovoltaic and wind turbine generation, and AC and DC loads. The proposed switchgear system consists of an inverter for connecting distributed generations and DC load, a static transfer switch (STS) that can control and interrupt the bidirectional power flow, and an intelligent electronic device (IED) that can control each facility using a communication system. Since the topology inside the switchgear is composed of DC bus, it can be operated as a plug-in type of system that can be used by simply connecting the converters of various distributed generations to the inverter in the developed switchgear system. In this study, we describe the overall structure of the proposed switchgear system and the operation of the components. In addition, prototypes of each facility are developed and the results of building a small testbed are presented. Finally, we verify the operation of the inverter by performing an experiment on the testbed and show that throughout a test sequence the proposed switchgear system works normally. The contributions of this study are the development of a plug-in type of switchgear for AC/DC and the actual test results presented through prototype development and testbed configuration.

A cyanine dye supramolecular FRET switch driven by G-quadruplex to monitor mitophagy

Mitochondrial autophagy (mitophagy) is critical to the quality and quantity control of mitochondria. Real-time monitoring of the occurrence of mitophagy is necessary for understanding mitochondrial metabolism and screening mitophagy-related therapeutic drugs. Here, we report a new type of fluorescence resonance energy transfer (FRET) switch constructed by the mixed assembly of two cyanine dyes. The FRET switch exhibits a highly selective fluorescence response to the G-quadruplex structure, and its fluorescence intensity decreases or increases correspondingly with the binding and separation of G-quadruplexes. This property enables the switch to track the progression and termination of mitophagy by identifying the G-quadruplex structures that enter the lysosome during autophagy. This work not only provides a new strategy for constructing non-covalent FRET probes, but also offers a reliable tool for tracking mitophagy.