Electrical Power Measurements Research Articles

Application of IoT Device-based Electric Power Measurement on Multifan System

Application of IoT Device-based Electric Power Measurement on Multifan System

ANALYSIS OF SURFACE ROUGHNESS OF REFRIGERATIONCOMPRESSOR FRICTION NODES DUE TO INSUFFICIENTLUBRICATION

The article presents an attempt to evaluate the roughness profiles of the components of the friction nodes inrefrigeration compressors due to insufficient lubrication. The damaging impact on the compressor operationunder various unfavorable operating conditions, including with little or no lubricant at all, was analyzed for areal refrigeration system using a dedicated test stand.The Embraco Aspera NE9213GK refrigeration compressor used was originally filled in by the manufacturerwith a polyester lubricant; for the purpose of the study, the R407C lubricant was applied. An accelerateddamage-controlled procedure was carried out on the compressor by reducing the amount of lubricant insubsequent operating cycles of the system. The amount of oil was adjusted by removing lubricant duringshutdown periods using a dedicated spigot in the body of the semi-hermetic compressor casing. The testingcontinued until the refrigeration compressor seized up.The test stand was used to analyze electrical power measurements at the time of intentional damage tothe compressor caused as a result of forced absence of lubrication. Additionally, the authors analyzed surfaceroughness profiles of the compressor sliding elements prone to wear, including crankshaft journals, pistonsurface, and a cylinder surface.

ANALISIS PENGUKURAN DAN PERHITUNGAN DAYA LISTRIK DENGAN SISTEM MONITORING BERBASIS WEB DI AREA INDUSTRI

The use of electricity must be paid more attention so that there is no overrun of electricity costs. Because of these problems, the author took the title Analysis of electrical power measurement and calculation with web-based system monitoring in industrial areas. This study uses a calculation and measurement research methodology. After measurements and calculations are carried out with system monitoring, the results of the calculation of electrical power measurements and observations are obtained by analyzing the percentage of error values from the comparison of values obtained from the measurement results using the energy monitoring system with the value of the measurement results using the Power monitoring sensor (PMS) and calculations using formulas. The final result of this study was obtained from the results of monitoring voltage, current, power, and power factor. For the results of the analysis of the percentage of electrical power error values, it was carried out by comparing the calculation of Power Monitoring Sensor (PMS) with Energy Monitoring System (EMS) with a monitoring time of 3 months, the first month had an error value of 0.6%, the second month had an error value of 0.2%, and the second month had an error value of 0.1%. Thus, the difference in error values is quite small, it can be concluded that this tool is said to be quite good in monitoring the use of electrical power in industrial areas.

Feasibility study of histotripsy with the clinical device FocalOne®

This study investigates the feasibility of generating histotripsy lesions in biological tissues ex vivo with the HIFU clinical device FocalOne® (EDAP-TMS). The Focal One® probe, composed of a 192-element imaging array and a 16-element therapy transducer operating at 3 MHz, was used with an upgraded amplifier (ADECE, 500W, 200 kHz-6MHz ) and a Verasonics Vantage system for passive cavitation and elastography monitoring. To ensure reproducibility, efficiency, and safety, efforts were directed into the electrical hardware stability and power optimization. Pressure fields, non-linear simulations, radiation force balance, and electrical instant power measurements were performed to validate that this setup can produce boiling histotripsy which is characterized in literature by a 10–18 MPa negative pressure and a shock amplitude >70 MPa. Typical treatment exposure was 10 ms repeated 60 times at 1 Hz pulse repetition frequency. Experiments in gel phantoms and fresh degassed bovine liver were performed. The ablations were detected with ultrasound B-mode at the focal spot. The millimetric lesions were confirmed by hyposignals on 3-D MRI scans and visual observation of cavities at the targeted spot after dissection. Further studies will be required to optimize treatment parameters and improve reproducibility of histotripsy using the Focal One® probe.

The effectiveness of duty cycling technique on air conditioning system during break period for comfort, energy and cost savings: A real case study in health center

This paper investigates the potential of duty cycling techniques for air conditioning (AC) systems in producing energy and cost savings and the impact on the indoor thermal environment, air quality, and environmental sustainability. The real case study concentrated on energy consumption practice during the break period between 13:00 to 14:00 in a lobby area of a Health Center. Site data measurements of electrical input power, energy, indoor air temperature and humidity, and indoor carbon dioxide (CO2) concentration were conducted. Two zero-cost strategies were studied and results were compared to baseline conditions. In general, the results show that all strategies can meet the indoor thermal environment and air quality requirements, except room temperature for Strategy 2 which ranges on average between 26.71 to 26.82C. In addition to the instant payback period (0 years), the results also indicate that as compared to baseline condition, Strategies 1 and 2 led to annual energy and cost savings of around 759.2 kWh (USD 64.40) and 1250.6 kWh (USD 106.08), respectively. In terms of environmental sustainability, Strategies 1 and 2 can avoid environmental CO2 emissions by 444.13 and 731.60 kg of CO2 per year, respectively. Due to these reasons and if the sensitivity of occupant comfort to room temperature during the break period can be tolerated, it is proposed that Strategy 2 is the best option for the AC system operation during the break period. Considering other buildings also adopted the same strategy, this small action can lead to a high impact, not only on energy and cost savings but also on environmental sustainability in the future.

Cobalt recovery from spent lithium-ion batteries using a rotating cylindrical electrode reactor

Abstract The cobalt electrodeposition from a leaching containing cathode-powdery of spent laptop lithium-ion batteries (LIBs) of different commercial brands, collected from local laptop repair shops, was investigated. Citric acid (0.14 M) and hydrazine (0.1 M) were employed as complexing and reducing agents in the leaching during 24 h. Cobalt, manganese and nickel concentrations in the leachate, obtained by the flame method in an atomic absorption spectrometer, are reported. A rotating cylindrical electrode reactor which consists of a rotating open bottom as cathode and a static outer cylindrical as anode was employed. The numerical flow patterns and cathode velocities that induce the presence of Taylor vortices inside and/or outside the cathode were investigated. RANS equations with the standard k−ε turbulence model and enhanced wall treatment was used. Electrical power measurements were performed to validate simulations. Cyclic voltammetry experiments with synthetic solutions were applied to determine the reduction potential of cobalt (found in −1.2 V vs SCE). Subsequently, electrolysis experiments were carried out at predetermined cathode speeds (50, 75, and 125 rpm), imposing a working cathodic potential of −1.2 V versus SCE during 12 h. Experimental results indicate that the best cobalt recovery rates and current efficiency coincide with the presence of Taylor vortices both inside and outside the cathode, i.e., at 50 rpm. The peak performance in cobalt recovery and current efficiency was recorded at 49 % and 47.3 %, respectively. Finally, the deposits obtained from each electrolysis test were removed from the cathode and analyzed via energy dispersive spectroscopy. The range of purity of Co obtained in the electrodeposit film were between 56.75 % and 74.8 %.

Research on abnormal diagnosis model of electric power measurement based on small sample learning

Research on abnormal diagnosis model of electric power measurement based on small sample learning

A Method of Reducing Errors Due to Sampling in the Measurement of Electric Power

Although data acquisition is a very usual technique, several aspects are not always considered, such as the synchronization of the acquired measures and the evaluation of the resulting errors. This paper aims to highlight this fact by the mathematical determination of the necessary correction and the implementation of software meant to evaluate the performances of acquisition systems. As an example, a three-phased acquisition system was developed in order to monitor the currents and voltages on the three phases. Also, other measures were performed, such as of power and phase. The components on each phase did not have to be fully identified because a whole system calibration could be performed in the first stage. The calibration consisted in finding the weighting coefficients for each measured quantity. The implemented solution for three-phased measure acquisition started from the hypothesis of a sampling frequency that respected the Shannon theorem. The distance between two samples was small enough to consider a linear evolution between two moments for the same measure. Errors that affected the above-mentioned measures, due to the fact that the samples were examined in different moments, were analyzed and brought to the minimum value. Finding a solution to reduce the sampling errors is closely related to reducing the costs.

Extended channel characterization of the low-cost sampling devices for the application in high-precision electric power measurement

The paradigm of low-cost metrology implies the application of low-cost measuring devices in order to achieve satisfactory precision of the relevant measuring quantities. This is particularly important in underdeveloped countries where it is necessary to improve their metrology capabilities to ensure satisfactory standards for industry requirements. Therefore, the previously published conference paper is extended, and the performance of low-cost sampling devices is investigated for the purpose of high-precision electricity measurement in relevant national metrology institutes or measurement laboratories. The performance of the DMM 3000 device and the DAQ970A digitizers compared with high-resolution (24-bit) ADC-based sampling devices such as the NI PXI 5922 and NI PXI 4461. One of the main contributions of this article is the characterization of the channels of the low-cost digitizers in sinusoidal and non-sinusoidal regimes along with the uncertainty analysis using Monte Carlo method which has been carried out as well.

Thermal design of a system for mobile hydrogen powersupply

Ever more stringent emission regulations for vehicles encourage increasing numbers of battery electric vehicles on the roads. A drawback of storing electric energy in a battery is the comparable low energy density, low driving range and the higher propensity to deplete the energy storage before reaching the destination, especially at low ambient temperatures. When the battery is depleted, stranded vehicles can either be towed or recharged with a mobile recharging station. Several technologies of mobile recharging stations already exist, however, most of them use fossil fuels to recharge battery electric vehicles. The proposed novel zero emission solution for mobile charging is a combined high voltage battery and hydrogen fuel cell charging station. Due to the thermal characteristics of the fuel cell and high voltage battery (which allow only comparable low coolant temperatures), the thermal design for this specific application (available heat exchanger area, zero vehicle speed, air flow direction) becomes challenging and is addressed in this work. Experimental methods were used to obtain reliable thermal and electric power measurement data of a 30 kW fuel cell system, which is used in the Mobile Hydrogen Powersupply. Subsequently, simulation methods were applied for the thermal design and optimisation of the coolant circuits and heat exchangers. It is shown that an battery electric vehicle charging power of 22 kW requires a heat exchanger area of 1 m2, of which 60 % is used by the fuel cell heat exchanger and the remainder by the battery heat exchanger to achieve steady state operation at the highest possible ambient temperature of 43,6 °C. Furthermore, the simulation showed that when the charging power of 22 kW is solely provided by the high voltage battery, the highest possible ambient temperature is 42 °C. When the charging power is decreased, operation up to the maximum ambient temperatures of 45 °C can be achieved. The results of maximum charging power and limiting ambient temperature give insights for further system improvements, which are: sizing of fuel cell or battery, trailer design and heat exchanger area, operation strategy of the system (power split between high voltage battery and fuel cell) as well as possible dynamic operation scenarios.

Estimating electric power consumption of in-situ residential heat pump systems: A data-driven approach

International Energy Agency predicts that the global number of installed heat pumps (HP) will increase from 180 million in 2020 to approximately 600 million by 2030, covering 20% of buildings heating needs. Electric power consumption is one of the main key performance indicators for the heat pump systems from techno-economic perspective. However a common issue prevalent in many existing heat pumps is the lack of electric power measurement. The modern installations might be equipped with electric power measurement sensors but this comes at a higher system cost for the manufacturers and end-users. The primary objective of this work is to propose a virtual measurement for estimating power consumption, thereby eliminating the need for field measurement of power for heat pumps. To achieve the objective, a data-driven approach is proposed. Firstly, the in-situ data is preprocessed through data merging, cleaning, and normalization. Then, input features are pre-selected using Spearman correlation coefficients, and further refined by addressing multicollinearity problem. Following this, Extreme Gradient Boosting (XGBoost) models and polynomial models are developed by considering different features as inputs. All models are finally validated against the in-situ data from multi-units of ground source heat pump (GSHP) and air source heat pump (ASHP) installations. The results showed that the electric power consumption of GSHP can be estimated with high accuracy (99% for R2, 10 W for MAE, and 1% for MAPE) through generic data-driven models using only four easy-to-measure input features. Taking three input features as inputs for ASHP generic model, the accuracy can be reached to 83% for R2, 125 W for MAE, and 9% for MAPE. The method presented in this paper can be applied to estimate power consumption of millions of heat pumps and consequently add a significant value as well as provide different types of services, such as cost-saving benefits for manufacturers and end-users, flexibility services for aggregators and electricity grids.

Perbandingan Nilai Daya Luaran Panel Surya Kapasitas 50Wp Terhadap Posisi Reflektor Cermin Datar

Solar panel systems are widely used to meet energy needs at this time. Solar panels have optimal power for 4 hours, namely 10:00 to 14:00. but this is still said to be not optimal if the angle of the static solar panels does not follow the movement of the sun. This can also be caused by weather factors that are covered in clouds. Previous research conducted by Tri Wahyu Ardianto used mirror reflectors but was not equipped with sensors and data storage. Based on this, to optimize solar panel energy, a flat mirror reflector design for solar panels has been made, equipped with four flat mirror reflectors on each side to form a large square. The solar panel is placed in the middle between the four flat mirrors. In this study, the measurement of electric power was carried out by carrying 3 variable angles for reflector positions, namely 0°, 60°, and 70°. The decision of the three reflector positions is made to find out the ratio of the maximum output power values. This system is also equipped with current, voltage, and light intensity sensors. The results show that the maximum output power of solar panels is shown at the reflector position of 60° with an average power output of 19.70 Watt followed by a reflector position of 70° with an average output power of 19.18 Watt and finally the reflector position is 0° with an average output power value of 14.87 Watt.

STUDY OF WAVE HEIGHT POTENTIAL FOR DETERMINING THE LOCATION OF WECS IN THE WATERS OF KETAPANG REGENCY BY USING CEDAS SOFTWARE

Ketapang Regency's increasing demand for electrical energy could lead to an energy crisis. According to these issues, the Sungai Kinjil and Kinjil Pesisir coastal communities in the Ketapang Regency have wave potential that can be used as energy for marine wave power plants. As a result, The expertise required to evaluate ocean wave resources and determine the output power of electrical energy produced by ocean waves. CEDAS and ArcGIS software is used for wave modeling, with CEDAS input data in the form of wave forecasting from BMKG wind data, bathymetry, and coastline data obtained from the official Indonesia Geospatial website, and primary data in the form of wave electric power measurement data obtained from Wave energy conversion system prototypes. CEDAS processing results show the highest wave height of 0,998 meters at a depth of 1,3 meters. The potential for electrical energy at the research site is 1,908–4,512 kw/m2.

Estimation of Energy Harvesting by Thermoelectric Cement Composites with Nanostructured Graphene and Metallic Oxides

The measurement of electrical power and efficiency of a thermoelectric generator (TEG) holds significant importance in the realm of thermoelectric materials research and development. The present investigation involves the measurement of thermoelectric characteristics, namely electrical conductivity, Seebeck coefficient, and thermal conductivity, of cement composites containing graphene nanoplatelets and metallic oxides (Fe2O3, ZnO, MnO2). These properties are then utilized to determine the electrical power output and efficiency of the aforementioned composites. It is possible to estimate a power output of up to 1.5 W per square meter when utilizing GnP-ZnO-added cement composites, given a temperature differential of approximately 50 °C. This paper additionally discusses the methodology for fabricating a cement composite-based structural TEG module with the aim of augmenting the overall output voltage, power, and efficiency of the system.

Traceable efficiency determination of a 2.75 MW nacelle on a test bench

In this paper, the efficiency of a 2.75 MW nacelle drivetrain on a test bench was determined traceably at various load points. For this purpose, so-called transfer standards for mechanical and electrical power measurement were additionally installed and integrated into the nacelle drivetrain. As torque measurement contributes greatly to the overall uncertainty, the static torque calibration was expanded to include additional influences present under rotation. An overall system efficiency of 89% was measured in the high torque and high speed range. The relative expanded measurement uncertainty for efficiency determination was between 0.30% and 0.72% over the entire operating range. Both the efficiency and the relative expanded measurement uncertainty were calculated for each operating point.

Application of electrical power measurements for process monitoring in ultrasonic metal welding

For the production of e-mobility components such as cable harnesses, battery cells, power electronics, etc., ultrasonic metal welding is well-established process of choice. These electrical applications require high quality for every single connection; single points of failure and no possibility of repair after installation or commissioning are state of the art. At present, the prevailing binding mechanisms and their sensitivity to the numerous process influencing variables like base material hardness, surface, and cleanliness are still the subject of research. In order to ensure sufficient quality despite the lack of process understanding, random destructive testing is carried out during ongoing production. The welding systems’ internal monitoring methods are currently not sufficient to make a prediction of the joint quality achieved. To determine process phases and extract features regarding the joint formation, the observation of process vibrations at the horn, anvil, and the components using laser-doppler-vibrometry, laser triangulation sensors or other suitable external measurement technology is common. These methods require external accessibility to the measurement position, not given in the industrial production environment. In this study, measurements of the high-frequency power signal of the welding system are conducted, and several machine learning models for quality prediction are set up. To ensure the robustness, several disturbances, e.g., changing material hardness and cleanliness, are taken into account. Thus, it will be evaluated to what extent an industrially suitable quality monitoring can be implemented by means of electrical measuring technology and how much more accurate such an external measuring system is compared to the possibilities already available in the welding system.

Alternate stabilization methods for CZTSSe photovoltaic devices by thermal treatment, dark electric bias and illumination

Reliable measurement routines are crucial for power rating and yield prediction of photovoltaic emerging thin-film technologies. Copper-Zinc-Tin-Sulfur-Selenium (CZTSSe) thin-film photovoltaic devices are an emerging technology made of abundant elements. Still, sufficient stabilization methods prior to electric power measurement are missing in the international standardization, while existing standards for other thin-film technologies do not work properly for CZTSSe. This study investigated methods for achieving power stabilization of the CZTSSe solar devices. Three complementary stabilization routines for the kesterite-based solar devices were investigated as an alternative to the existing international device testing standards: rapid annealing, dark electric biasing and different operating points under illumination. The typical number of stabilization cycles for power stabilization was between 3 and 6 cycles of rapid annealing, dark electric bias and illumination with a power loss of -19.5%, -11.4%, and -1.9%, for the respective methods. The dark electric bias method was found to provide the most reliable average result for power stabilization. All stabilization methods proved to have the potential to work sufficiently in stabilizing the CZTSSe devices for standardized power measurement.

EXPERIMENTAL STUDY OF CIRCULAR CUT OFF ENDPLATE EFFECT ON THE SAVONIUS TURBINE

The Savonius turbine is widely used because it has a simple design. However, the Savonius turbine has a lower efficiency than the Horizontal Axis Wind Turbine (HAWT). Several studies have been conducted to increase the efficiency of the Savonius turbine. Turbine performance can be improved by reducing the negative vortex by creating a flushing effect. This experiment was conducted to determine the impact of circular cut-off end plates on the Savonius turbine. The research results are shown through turbine performance data on wind turbine angular speed, electric power, static torque, and efficiency. The wind turbines with circular cut-off endplates had higher angular velocities than conventional Savonius turbines. The angular velocity measurement is carried out when the turbine is unloading. Meanwhile, the electric power and static torque of a conventional turbine are more significant than a modified turbine. The measurement of electric power and static torque is carried out when the turbine is in a generator-loaded condition (loading).

The AC amplitude and channel characterization of high-resolution digitizers

High-resolution (24-bit) ADC based sampling devices e.g. NI PXI 5922 and NI PXI 4461 are usually used for precise electric power measurement purpose so it is required to characterize them in a proper way. According to that, several measurement techniques are proposed to characterize ac amplitude and channel characteristics at the maximum frequency of up to 100 kHz. An automated test and calibration system based on a planar multijunction thermal voltage converter and a modular electronic instrumentation platform has been developed. Furthermore, two ADCs, i.e. NI PXI 5922 and NI PXI 4461 have been compared with reference standard (Swerlein algorithm) to investigate their precision in RMS amplitude measurement of ac signals. In addition, this paper presents the PXI digitizers’ channel characterization in both sinusoidal and non-sinusoidal regime as the main contribution which results in comprehensive insight into digitizers’ performances and their mutual comparison. Accordingly, relevant uncertainty analysis is presented as well.

Analysis of Errors in Active Power and Energy Measurements Under Random Harmonic Distortion Conditions

Abstract As harmonic distortion of voltage and current is reality in the power system, the need for accurate measurement of electrical power and energy goes beyond the instruments’ specifications and calibration procedures regarding pure sine wave signals. Several international standards and recommendations provide test signals for examination of electricity meters under non-sinusoidal conditions, however, not all of the test signal parameters’ possible states are faithfully represented in those documents. Because the high order harmonics may possess random amplitudes and phase shifts in relation to components at fundamental frequency, it is important that the meter’s performance is verified with random waveforms as well. The non-linear dependence between the measured power/energy and the phase shifts, both between fundamental and harmonic components, provides additional complexity of such an analysis. Simple test signals, which are in accordance with the standards’ demands and propositions, are used for determination of the measurement error in case of different harmonic distortion parameter change. In order for a general error function for any measurement device to be determined, mathematical modelling, regarding the results from multiple tests, is performed. The mathematical model presents a strong dependence between a single component’s phase shifts and a meter’s error and it provides a systematization of all signal parameters’ influence on the measurement accuracy.