Showing papers on "Voltage drop published in 2023"
TL;DR: In this article , a feeder planning model for the urban distribution network considering various practical requirements is proposed, and the proposed model is recast as a mixed integer linear programming (MILP) problem, and it can be solved by the state-of-the-art commercial solver.
Abstract: There is a significant gap between academic research and practical application for power distribution system planning (PDSP). For most of the existing PDSP models in academic research, cost is used as the objective function, and the most common constraints are power flow equality constraints, bus voltage or voltage drop limits, substation and feeder capacity limits, etc. Although various advanced models and methods have been proposed, they are rarely used in real distribution system companies. This paper proposes a new feeder planning model for the urban distribution network considering various practical requirements. According to field investigation, “supply electricity to loads using nearby power sources” is used as the objective, and it is analytically expressed by load moment. Block loads, practical street layout, meshed network configuration, connection mode of feeders, non-crossing requirement of feeders, power supply radius, etc., are all respected and embedded in the model. The proposed model is recast as a mixed integer linear programming (MILP) problem, and it can be solved by the state-of-art commercial solver. The effectiveness and validity of the proposed model are illustrated on a 9-block test system and a real 22-block district distribution system.
26 citations
TL;DR: In this article , the electrical and thermal characteristics of Li-ion battery under different external short circuit current were analyzed combining with the failure characteristics of the electrodes, and the performance of a short-circuited battery was evaluated as well as its potential thermal risks.
3 citations
TL;DR: In this paper , a sediment microbial fuel cell (SMFC) was added to an open channel previously containing another SMFC and voltage loss was investigated when the new SMFC was located either in downstream or upstream of the former SMFC.
2 citations
TL;DR: In this paper , two wide-area approaches based on network and loads parameters are proposed to deal with fault-induced delayed voltage recovery (FIDVR) and short-term voltage instability (STVI) phenomena in networks with high penetration of induction motor loads.
Abstract: The fault-induced delayed voltage recovery (FIDVR) and short-term voltage instability (STVI) phenomena appear in networks with high penetration of induction motor loads because the increase in requested reactive powers of these loads prevents the voltages from quickly returning to their pre-fault levels. Load shedding (LS) is one of the ways to deal with FIDVR and STVI and reduce the imbalance between the generation and demand of reactive power. Under-voltage (UV) relays that disconnect loads during voltage drop cannot effectively deal with this phenomenon because of their inability to detect the effective loads on the reduction of FIDVR and STVI severities. Therefore, the operation of UV relays during these phenomena causes unnecessary load disconnection, and the interference of their operations with FIDVR and STVI must be avoided. This paper presents two wide-area approaches based on network and loads parameters, the first of which deals with the most critical FIDVR, and the second tries to simultaneously handle critical FIDVRs of all buses. Also, bus prioritization for LS during STVI has been addressed. Simulation results revealed the better performance of the proposed approaches than the previous ones in terms of the amount of LS and the number of selected buses for LS.
2 citations
TL;DR: In this article , the authors investigated the transients during the startup of an industrial centrifugal pump with a line-start permanent magnet synchronous motor and found that when the voltage on the motor terminals is reduced by 10%, the synchronization is delayed.
Abstract: The use of Line-Start Permanent Magnet Synchronous Motors (LSPMSM) improves the efficiency of conventional direct-on-line electric motor-driven fluid machinery such as pumps and fans. Such motors have increased efficiency compared to induction motors and do not have an excitation winding compared to classical synchronous motors with an excitation winding. However, LSPMSMs have difficulty in starting mechanisms with a high moment of inertia. This problem can be exacerbated by a reduced supply network voltage and a voltage drop on the cable. This article investigates the transients during the startup of an industrial centrifugal pump with a line-start permanent magnet synchronous motor. The simulation results showed that when the voltage on the motor terminals is reduced by 10%, the synchronization is delayed. The use of the cable also leads to a reduction in the voltage at the motor terminals in a steady state, but the time synchronization delay is more significant than that with a corresponding reduction in the supply voltage. The considered simulation example shows that the line-start permanent magnet synchronous motor has no problems with starting the pumping unit, even with a reduced supply voltage. The conclusions of this paper support a wider use of energy-efficient electric motors and can be used when selecting an electric motor to drive a centrifugal pump.
2 citations
TL;DR: In this article , the authors proposed a 17-level switch capacitor-based multi-level inverter (SC-MLI) with less components in order to maintain a constant voltage across the capacitors, to obtain higher voltage gain with fewer parts, fewer conducting routes, lower TSV, and to create a more affordable and effective inverter.
Abstract: Significant interest has been shown in switched capacitor (SC)-based multi-level inverters (MLIs), which decrease the need for a DC supply and enhance power quality. The common issues with SC-MLIs include an uneven distribution of conducting paths, increased voltage drop across capacitors, the sum of all inverter DC link voltages across the highest voltage rated switches, and a higher total standing voltage (TSV). The purpose of this paper is to create a SC-MLI with less components in order to maintain a constant voltage across the capacitors, to obtain higher voltage gain with fewer parts, fewer conducting routes, lower TSV, and to create a more affordable and effective inverter. The structure of the MLI is created by a cascade interconnection between the number of SC cells. A single input multiple output (SIMO) converter boosts the DC-link voltage over the stable DC voltage of the solar panels using a modified perturb and observe (P&O) method. Additionally, fewer switches in the conduction path and 50 % of the switches operating at normal frequency guarantee a decrease in an overall loss of power in the proposed network. The benefits of the recommended MLI are made clear by comparing them with 17-level MLIs in terms of the number of elements, stress, gain, and cost factor. Detailed experimental results are shown under various transient conditions to show that the 17-level prototype is operationally viable. The total harmonic distortion (THD) is found to be identical and is less than 5 %, which meets IEEE standards.
2 citations
TL;DR: In this article , the non-destructive and fracture test techniques were studied for micro-crack detection in the advanced high strength steel (AHSS) notched sheets, and the results confirm for the first time that both techniques can be induced to indicate micro crack from fracture behavior of AHSS sheet in forming and AE technique can detect the crack initiation faster and more effective than DCPD.
Abstract: In this work, the non-destructive and fracture test techniques were studied for micro-crack detection in the advanced high strength steel (AHSS) notched sheets. Crack initiation of JAC780Y during tensile loading was investigated by Direct Current Potential Drop (DCPD) and Acoustic Emission (AE) techniques. The results confirm for the first time that both techniques can be induced to indicate micro-crack from fracture behavior of AHSS sheet in forming and AE technique can detect the crack initiation faster and more effective than DCPD.
1 citations
TL;DR: In this article , a dual-slope resistance to digital converter (RDC) for compensating lead resistance is presented, which completes measurement in one charging-discharging cycle only, hence provides an improvement to existing RDCs based on direct microcontroller interfaces (DMIs).
Abstract: A novel dual-slope resistance to digital converter (RDC) for compensating lead resistance is presented. The RDC uses a dual-slope analog-to-digital converter (ADC) structure along with three switches and a diode. It completes measurement in one charging–discharging cycle only, hence provides an improvement to existing RDCs based on direct microcontroller interfaces (DMIs), where two or three charging–discharging cycles are required. Moreover, it incorporates the feature of lead resistance compensation in dual-slope RDCs. The scheme works by connecting the resistive sensor to the input terminal of the integrator of the dual-slope ADC. In the charging path (or mode), sensor resistance is presented along with a lead resistance; and in discharging path, sensor resistance is bypassed, and only lead resistance is there. The difference between the RC time constant during these two modes is used to find the sensor resistance. The diode is used to turn on a switch for bypassing the resistive sensor. The diode voltage drop is not there in the charging and discharging path, which is another novelty. A detailed error analysis is also carried to evaluate the performance of the scheme considering switch resistance, diode voltage drop, voltage mismatch, and opamp noises. The scheme works with low-value resistive sensors ( $\approx 100~\Omega $ ), a feature not found in the existing dual-slope RDCs. The hardware prototype of the proposed scheme on the breadboard shows a measurement time of 2.09 ms with an average error of ±0.04% at 100 $\Omega $ when lead resistance varied from 20 to 100 $\Omega $ . The scheme takes 23.44% less time for measurement.
1 citations
TL;DR: In this article , the authors proposed a voltage and frequency restoration method based on the dynamic average consensus algorithm and an accurate reactive power-sharing mechanism based on a first-order consensus and virtual impedance method.
1 citations
TL;DR: In this article , an auxiliary frequency controller is proposed to control output voltage frequency at inverter station to improve disturbance ride-through capability of voltage source converter based on high voltage direct current (VSC-HVDC) supplying industrial plant.
1 citations
TL;DR: In this article , a mathematical junction temperature estimation model based on the relationship between saturation voltage drop and different currents is established, whose accuracy depends on the prior narrow range junction temperature calibration.
Abstract: Junction temperature is the most important factor to induce the insulated gate bipolar transistor module failure and conduct operational management. In-situ calibrated method and junction temperature calculation model are proposed to timely indicate the junction temperature for the electric vehicle drive system. It aims to solve that the conventional calibration methods need to be calibrated in the temperature chamber and the model cannot meet variable current conditions, which ignores the effects of the stray parameters of electrode connection on the on-state voltage. A mathematical junction temperature estimation model based on the relationship between saturation voltage drop and different currents is established, whose accuracy depends on the prior narrow range junction temperature calibration. A control strategy for the in-situ calibration is proposed to generate an instantaneous large current by creating a zero-torque condition and using integrated negative temperature coefficient thermistors, current sensor, and on-state voltage measured circuit when the new-energy vehicle is in an idle state. Experimental results prove that the proposed in-situ calibration method can be realized totally inside the electric vehicle, which can serve the full-service lifetime of the electric vehicle with high precision.
TL;DR: In this article , a semi-analytical model was proposed to extract barrier dopant polarity, doping concentration, and thickness, as well as contact and absorber layer doping concentrations, all from a capacitance-voltage measurement.
Abstract: Capacitance–voltage measurements are a powerful technique to determine doping profiles of semiconductor pn junctions and Schottky barrier diodes. The measurements were recently extended to III-V-based mid-wavelength nBn infrared detectors, and absorber doping densities have been extracted using the widely accepted Schottky approximation, where the potential drop across the device is assumed to be across the depleting absorber layer. However, this approach is limited to when the absorber region of the nBn is under high reverse bias and thus is only able to extract the absorber region doping profile. Here, we introduce a semi-analytical model that is capable of extracting barrier dopant polarity, doping concentration, and thickness, as well as contact and absorber layer doping concentrations, all from a capacitance–voltage measurement. Rather than solely considering the potential drop across the depleting layers, it considers the potential drop across the accumulating layer as well. This negative charge accumulation occurs for the contact and absorber layers in the case of reverse and forward biases, respectively. This allows for a single model to be applied to a capacitance–voltage curve at forward and reverse biases and it can provide regions of bias where the absorber transitions from depletion to accumulation. We compare the agreement of the semianalytical model with modeling results from commercially available finite element method software and experimental capacitance–voltage data. Finally, we show that the method is consistent with the Schottky approximation of extracting absorber doping densities at high reverse bias and discuss the model's limitations.
TL;DR: In this article , the authors presented experimental results on thermal runaway suspension with battery health retention, for the first time, by analyzing the temperature and voltage evolution of commercial 18,650 cells with Li-ion chemistry during step-heating thermal runaway test in an accelerating rate calorimeter, it was found that the voltage signal has a sudden drop corresponding to a similar temperature of 135 °C, before the occurrence of thermal runaway.
TL;DR: In this paper , a superconducting feeder cable is proposed to enable zero-resistance power transmission on electric railways, where the length of one superconding cable is at most 500 m, although the average distance between substations is about several kilometers.
Abstract: Electric railways have several problems due to the electrical resistance of feeder lines, such as transmission loss and voltage drop. In order to solve these problems, we have been developing a superconducting feeder cable, which enables zero-resistance power transmission. Due to restrictions during transportation, the length of one superconducting cable is at most 500 m, although the average distance between substations is about several kilometers. Hence, to introduce superconducting feeder cables between substations, it is required to join superconducting feeder cables to each other at a railway site. This article reports analytical and experimental results of joining tests of the superconducting tape, assuming the joining of superconducting feeder cables at railway sites, and gives standards for the joining of superconducting feeder cables.
TL;DR: In this paper , the locations of placement of a static var compensator in an experimental IEEE 14-bus system was identified and the voltage drop in different buses in an IEEE 14 bus system was calculated by the standard formula.
Abstract: Given the concern for maintaining voltage stability in power systems integrated with renewable power systems due to a mismatch in generation and demand, there remains a need to invoke flexible alternating current transmission system (FACTS) devices in the distribution network. The present paper deals with identifying the locations of placement of a static var compensator in an experimental IEEE 14-bus system; the voltage drop in different buses in an IEEE 14-bus system is calculated by the standard formula. The total voltage drop in the network (TVDN) is also calculated as a reference. The ranking of buses in order of decreasing voltage drop is made, and the weak buses are identified as those showing the maximum or near-maximum voltage drop for the installation of a Static Var Compensator (SVC). The optimum usable size is calculated using a Genetic Algorithm approach to optimize the installation cost. After size optimization, installing a 2 MW solar generator is considered for the weak and most potential bus, which suffers from voltage drops or power loss. Based on the generator at the weakest bus, the total power loss in the network is calculated and compared with a similar method to assess the efficiency of the proposed model. Thus, the voltage stability enhancement problem is solved by applying a Genetic algorithm (GA) to optimize SVC size and using the Total Voltage Drop in Network (TVDN) method to identify weak buses in the systems. It is found that the performance of the proposed system is comparable with another existing system. It is further observed that a gain in power loss to 6.56% is achievable by adopting the proposed strategy, and the gain is better than the other system.
18 May 2023
TL;DR: In this article , the crowbar active circuit protection method was proposed to prevent the rotor side converter from destroying the rotor and the DFIG from being damaged by voltage dip on the grid.
Abstract: This work presents the crowbar active circuit protection method in case of voltage dips on the grid affecting the DFIG based wind power conversion system (WPCS). The sudden voltage drop produces high values of stator and rotor currents which also leads to an increase of the DC bus voltage. Without protection, the rotor side converter (RSC) can be destroyed and the DFIG can be damaged. With the proposed method, the currents will be limited to prescribed values at the onset and at the disappearance of the fault, which will allow to keep the DFIG connected to the grid during the voltage dip and to recover its normal operation after the fault disappearance.
19 Mar 2023
TL;DR: In this article , a double-sided cooling TO-264 package, and driver design of BTRAN was characterized and reported, and the authors obtained ultra-low conduction and switching power losses in switching modes of operation, showing the promise of utilizing B- TRAN™ in many power electronics applications such as Electric Vehicle (EV) traction inverters, EV Off-Board Chargers, Solid-State Circuit Breakers (SSCB), Bidirectional Power Converters, Battery Disconnect Switches, IGBT Common- Emitter applications, and Matrix Converters.
Abstract: A BTRAN™ device, rated at 1200V/SOA in a double-sided cooling TO-264 package, and driver design, are characterized and reported in this paper. Both DC and switching characterizations on the wafer and packaged levels validated the predicted simulation results reported last year at APEC 2022 [1]. Packaged devices showed bidirectional operation and symmetrical performance in both directions. The breakdown voltage, on-state voltage, and current gain (ß) were measured to be 1280 V, 0.6-0.8 V, and 4, respectively [2]. Double Pulse Testing (DPT) showed significant improvement over the comparative devices in the market. We obtained ultra-low conduction and switching power losses in switching modes of operation, showing the promise of utilizing B- TRAN™ in many power electronics applications such as Electric Vehicle (EV) traction inverters, EV Off-Board Chargers, Solid-State Circuit Breakers (SSCB), Bidirectional Power Converters, Battery Disconnect Switches, IGBT Common- Emitter applications, and Matrix Converters. At 800V/14A testing, the emitter-emitter on state voltage drop is 0.6V; under the same condition, the two best common-emitter IGBT bidirectional switches [3], [4] are shown to be 2.65V. Thus BTRAN™ offers close to an 80% reduction in conduction power losses (Figure 11 and Figure 13).
TL;DR: In this paper , a wind turbine is mounted on the front of the vehicle to receive wind and the generator produces electricity from the wind and stores them in another battery, and the vehicle moves with the pre-charged battery and a voltage sensing circuit is placed on one or more batteries of a vehicle to detect the drop in voltage.
Abstract: Abstract: An electric powered vehicle has a bank of batteries that runs the entire vehicle. This work focuses on charging the batteries of the vehicle on the run. This is done by capturing the wind that acts opposite of a moving car. There is always the flow of wind as long the cars moves with a speed. A wind turbine is mounted on the front of the vehicle to receive wind. The generator produces electricity from the wind and stores them in another battery. The vehicle moves with the pre-charged battery and a voltage sensing circuit is placed on one or more batteries of the vehicle to detect the drop in voltage. In such case the reservoir battery that gets charged through wind switches the position with the low voltage battery and continues to run the vehicle while the other battery gets charged. This process can go on until the vehicle comes to stationary. While one of the limitations of the electric vehicles is their short travel range compared to their excessive charging time. The travel range can be extended by charging the battery on the motion. This paper mainly focuses on the design of the wind powered car and to determine the power required for driving the system.
28 Mar 2023
TL;DR: In this paper , it is shown that if the batteries of unequal capacity are connected parallel, the current will tend to divide between the batteries in the ratio of capacities (actually, internal resistances).
Abstract: Lead acid battery may be used in parallel with one or more batteries of equal voltage. When connecting batteries in parallel, the current from the charger will tend to divide almost equally between the batteries. No special matching of batteries required .If the batteries of unequal capacity are connected parallel, the current will tend to divide between the batteries in the ratio of capacities (actually, internal resistances).When charging batteries in parallel, where different ratios of charge are to be expected, it is best to make provisions to assure the currents will not vary too much between batteries. Lithium batteries can be connected to generate more energy to run larger motors or extra capacity. Connecting the lithium batteries in parallel is one way to increase the ampere-hours of a battery. As far as disadvantages, placing batteries in parallel can make them take longer to charge. Also, the lower voltage means higher current draw and more voltage drop. It may be difficult to power large applications, and one need thicker cables. Imbalanced lithium-ion cells die the first time one try to use them. This is why balancing is absolutely required. Battery cells, especially lithium cells are very sensitive to overcharging and over-discharging. Balancing is only necessary for packs that contain more than one cell in series. Parallel cells will naturally balance since they are directly connected to each other, but groups of parallel wired cells, wired in series (parallel-series wiring) must be balanced between cell groups.
TL;DR: In this paper , a transformerless static synchronous series compensator (TL-SSSC) was proposed to mitigate voltage distortion in a power distribution line with renewable generations, which is computationally efficient and effective in mitigating voltage distortion due to faults occurring at different locations along the distribution line.
Abstract: This paper explores a transformerless static synchronous series compensator (TL-SSSC) for mitigating voltage distortion in a power distribution line with renewable generations. A novel deadbeat current control scheme with time delay compensation is proposed which models the a-b-c three phase line with TL-SSSC plus its LC filters and predicts the compensating voltages to be injected by the TL-SSSC. Without resolving measured voltages and currents into positive and negative sequences, the scheme is computationally efficient and effective in mitigating voltage distortion due to faults occurring at different locations along the distribution line. It also eliminates the problem of inaccurate compensation voltage caused by inverter filter choking voltage drop. The paper also analyses the power controllable ranges for a TL-SSSC under different unbalanced voltage ratios. The proposed TL-SSSC and control scheme is validated using Typhoon Hardware-In –Loop (HIL) device. Experimental results on mitigation unbalanced voltages of a 11kV transmission line confirm the effectiveness and high performance.
TL;DR: In this article , the authors used the potential drop method to identify local stress concentration zones and assess the metal deformation degree in these zones, using a sinusoidal current source.
Abstract: This work is devoted to the study of the using the potential drop method possibility to identify local stress concentration zones and assess the metal deformation degree in these zones. Paper presents the finite element modeling results of the current circuits propagation in objects with locally deformed regions that occur in places of increased mechanical stresses concentrations. To identify areas with varying degrees of deformation, a method for recording the specific electrical conductivity increment is proposed (Δρ/ρ0) according to the voltages values δU detected as application result of the potential drop non-destructive method using a sinusoidal current source. The current circuits excitation at frequencies f less than 10000 Hz allowed us to determine the most informative approximating function δU(f) parameters, allowing to synthesize a model of multiple linear regression correlating with the parameter Δρ/ρ0 values, and with the degree of product material deformation.
TL;DR: In this paper , the Simulink method is used to simulate and analyze active and reactive power at each cluster and the average was obtained by adding up electrical power received every hour, then dividing by 10, the number of buses connected to the load.
Abstract: The power distribution system applied in Indonesia is the radial system. The system is considered to be the simplest and most economical. The bad or good distribution of electrical power can be observed from the quality of the distribution of power supplied. Voltage has to be monitored and kept constant. An analysis was conducted at Bendul Merisi Feeder which has 11 buses, to find the value of supplied power also the value of voltage drop of each bus. The Simulink method is used to simulate and analyze active and reactive power at each cluster. Based on the result of the simulation analysis, the average was obtained by adding up electrical power received every hour, then dividing by 10, the number of buses connected to the load. The smallest average of active power supplied to each bus happened at 09.00 a.m., i.e. 112137.94 VA. The biggest value of active power supplied to each bus happened at 1.00 p.m., i.e. 115129.05 VA. The total voltage drop that occurred in the distribution supply was 224 volts or 1.12% out of 20 kV supplied, indicating that the supply of voltage was according to the standardized rule implemented by PLN (State Electricity Company), i.e. the voltage drop should not exceed the maximum of 10%.
01 Mar 2023
TL;DR: In this article , the performance of the system is improved by reducing the impacts through optimally placing the FACTS device under various load conditions (100, 150, 175% and 200% of base load) by using one of the modern optimization techniques, i.e., mutation based particle swarm optimization algorithm (Hybrid PSO algorithm).
Abstract: Due to the existence of reactive component of current in transmission lines causes adverse impact on the power system network. It includes network power losses, reduction of line capacity and voltage drop. The listed impacts can be reduced by using FACTS devices. A qualified analysis has been made based on different factors in presence and absence of FACTS devices such as voltage profile improvement, loss minimization and voltage stability improvement. Newton-Raphson (N-R) approach is applied for load flow analysis before and after insertion of FACTS device. In this research article, the performance of the system is improved by reducing the impacts through optimally placing the FACTS device under various load conditions (100%, 150%, 175% and 200% of base load) by using one of the modern optimization techniques, i.e., mutation based particle swarm optimization algorithm (Hybrid PSO algorithm). Most severe buses are identified by using a novel index method called Unification Index (UCI). To authenticate the expediency of the proposed approach, simulations studies are performed on a standard IEEE 30-bus power system. Encouraging results (in terms of power losses reduced by 19.91%) are obtained. Simulation outcomes justify the superiority of the proposed approach is competent compared with other approaches.
TL;DR: In this paper , external loading pressure and thermal interface material (TIM) were applied to reduce the interfacial thermal contact resistance, and the TEG output voltage and power were measured under constant temperature boundary and heat flux conditions.
Abstract: Heat conduction boundary conditions play a crucial role in the performance of thermoelectric generators (TEG). The TEG output voltage and power were measured under constant temperature boundary and heat flux conditions to evaluate the TEG performance under different heat conduction boundary conditions. External loading pressure and thermal interface material (TIM) were applied to reduce the interfacial thermal contact resistance. In our measurement setup, a fast-response electronic load was used for the rapid current-voltage scan, which can eliminate the thermal drift caused by the Peltier effect. A guard heater arrangement is used to minimize heat loss. In constant temperature boundary conditions, reducing the thermal contact resistance can increase the effective temperature drop across the TEG module and significantly improve the output voltage and power. But in the constant heat flux conditions, since the heat flux flow through the TEG is unchanged, the temperature drop across the TEG was unaffected by the thermal contact resistance. As a result, the TEG performance was lightly influenced by the thermal contact resistance.
TL;DR: In this article , a discrete-time distributed secondary control strategy for DC microgrids is proposed to guarantee flexible current sharing and ensure accurate voltage regulation, which allows for both resistive loads and constant power loads (CPLs, nonlinear loads).
Abstract: DC microgrids have been widely applied in industrial applications recently due to their robust reliability, high efficiency, and flexible accessibility to sustainable energy resources. Various distributed secondary control methods have been developed for DC microgrids to achieve current sharing and voltage restoration. However, the majority of these methods are presented with continuous-time controllers while digital controllers in real systems are in discrete time. Considering the inherent discrete-time property in practical implementations, this paper proposes a discrete-time distributed secondary control strategy. Using the concept of “virtual voltage drop,” the proposed controller guarantees flexible current sharing and ensures accurate voltage regulation. Moreover, the proposed strategy allows for both resistive loads (linear loads) and constant power loads (CPLs, nonlinear loads). Both simulation and experiments are conducted to demonstrate the presented strategy.
21 Jun 2023
TL;DR: In this article , the authors aim to improve the voltage drop and increase the resilience of the multi-carrier distribution network in the event of a short-circuit fault, resulting in the provision of 10% of the total load and an improvement in subscriber welfare.
Abstract: Abstract Power quality has become a vital factor because of the simultaneous use of electric and gas energies in a network (multi-carrier grid) as well as the use of modern electrical equipment. Poor electricity quality is defined as the presence of changes, distortions, or disturbances in voltage, current, and frequency quantities that cause the failure or improper operation of the subscribers' equipment. In this research, we aim to improve the voltage drop and increase the resilience of the multi-carrier distribution network (Energy Hub) in the event of a short-circuit fault, resulting in the provision of 10% of the total load and an improvement in subscriber welfare. To improve the voltage drop, we first need fast fault detection, which is accomplished by using an FCL filter, which is capable of detecting any short-circuit fault in the shortest amount of time by combining the method of estimating frequency fluctuations and the Prony method. After detecting the fault, a combination of DVR and D-STATCOM (DDS) is used to compensate for the voltage drop. The amount of increase in subscriber resilience and welfare will then be investigated. The simulation results show proper performance in identifying the short-circuit fault to prevent the subscribers' collapse and blackout.
TL;DR: In this paper , stacking configurations of 3D-printed PMFCs are investigated to determine the amplification potential of bioelectricity, and the results indicated that the scale up of PMFC technology is possible in field applications to continuously generate electricity while growing edible plants.
Abstract: The prevalence of non-renewable energy has always been a problem for the environment that needs a long-term solution. Plant-Microbial Fuel Cells (PMFCs) are promising bioelectrochemical systems that can utilize plant rhizodeposition to generate clean electricity on-site, without harming the plants, paving the way for simultaneous agriculture and power generation. However, one of the biggest hurdles in large-scale PMFC application is the diffused nature of power generation without a clear path to consolidate or amplify the small power of individual cells. In this study, stacking configurations of 3D-printed PMFCs are investigated to determine the amplification potential of bioelectricity. The PMFCs designed in this study are made of 3D-printed electrodes, printed from 1.75 mm Proto-pasta (ProtoPlant, USA) conductive PLA filament, and a terracotta membrane acting as the separator. Six cells were constructed with the electrodes designed to tightly fit with the ceramic separator when assembled. An agriculturally important plant (S. Melongena) was utilized as the model plant for testing purposes. Stacking of cells in series had resulted in severe voltage loss while stacking of cells in parallel preserved the voltage and current of the cells. Cumulative stacking verified the increasing voltage losses as more cells are connected in series, while voltage and current were generally supported well as more cells were connected in parallel. Combination stacks were also investigated, but while 2 sets of 3 cells in parallel stacked in series generated proportionately larger power and power density compared to individual cells, the drop in current density suggests that pure parallel stacks are still more attractive for scaling up, at least for the proposed stake design in this study. The results of this study indicated that the scale up of PMFC technology is possible in field applications to continuously generate electricity while growing edible plants.
TL;DR: In this article , an adaptive active voltage-type arc suppression (AAVAS) strategy is proposed to suppress the residual current at the grounding point, which can effectively offset the influence of voltage drop on faulty-phase line impedance.
Abstract: The reliable extinguishment of a single phase-to-ground arc is the key issue for safe and reliable operation in the distribution network. However, since the existing arc suppression methods are normally affected by the line parameters, the residual current (RC) at the grounding point still exists, then the grounding arc is hard to be extinguished reliably. Thus, an adaptive active voltage-type arc suppression (AAVAS) strategy that can reliably inhibit the RC at the grounding point is proposed in this article. First, the mechanism of the traditional voltage-type arc extinguishing method affected by the line parameters is proved, and the variation rules are given for the RC under different fault distances and grounding resistance. Second, the variation characteristics are analyzed for the faulty line current before and after arc extinguishing. On this basis, it is proposed to add the residual voltage compensation ring to the traditional voltage-type control strategy, which can effectively offset the influence of voltage drop on faulty-phase line impedance. Then, the Bode diagram analysis shows that the presented strategy performs well regardless of ground-fault conditions. Finally, the feasibility and effectiveness of the proposed AAVAS strategy are verified by the simulation and experiment results.