Deddy Kurniadi

Development of battery management system for cell monitoring and protection

Battery has an important role as energy storage in electricity system utilization such as in electric vehicle and in smart microgrid system. Battery Management System (BMS) is needed to treat the dynamics of energy storage process in the battery in order to improve the performance and extend the life time of battery. In this paper, BMS cell monitoring and protection has been designed and tested for Lithium Ferro Phosphate (LFP) battery cells. The BMS cell monitoring function has been able to measure the battery parameters such as the voltage and current dynamics of each cell. The data taken from the BMS cell monitoring experiment is used to estimate the state of charge (SOC) of battery which is based on coulomb counting with coulomb efficiency ratios. The BMS cell monitoring function has successfully demonstrated the presence of unbalanced cell voltages during both processes of charging and discharging as well. From the analysis, the existence of capacity and energy fades was also investigated for every discharging and charging cycles. Based on the BMS cell protection experiment results, overcharged and over discharged protections have successfully been demonstrated for the battery cells. The charging process is disabled when the voltage of the corresponding battery cell exceeds its high limit (HLIM) at 3.65V, and the battery will be available for charging when all of the cell voltages are below their boundary limits (CAVL) at 3.3V. The discharging process will be disabled when the battery cell voltage is lower than the corresponding low limit (LLIM) at 2.5 V. The battery will be available again when all battery cell voltages are above their discharge available (DAVL) voltage at 2.8V. The proposed BMS cell monitoring and protection has shown its function as a data acquisition system, safety protection, ability to determine and predict the state of charge of the battery, and ability to control the battery charging and discharging.

Optimization of capacity and operational scheduling for grid-tied microgrid using pumped-storage hydroelectricity and photovoltaic

This paper deals with the optimization of capacity and operation scheduling for a grid-tied microgrid system. Photovoltaic power system is used as renewable energy source and pumped-storage hydroelectricity is used as energy storage. The physical models of the photovoltaic system and pumped-storage hydroelectricity are developed. The objective function is formulated based on capital and operational costs of individual systems. The constraints for the optimization are defined considering the model of systems, operational limitations, and performance requirements. The capacity and the operation scheduling of the photovoltaic and pumped-storage hydroelectricity are optimized based on the solar insolation data and average load demand tied to the microgrid. The performances required are high renewable energy penetration and low curtailed renewable energy. The optimization problem is solved using the mixed integer linear problem (MILP). With the proposed scheme, the renewable energy penetration ratio achieves 50%, which is acceptable. Moreover, the curtailed renewable energy ratio of 1.22% is obtained, which is very low. Both achievements, the acceptable renewable energy penetration ratio and the low curtailed renewable energy ratio, are the key outcomes of this research.

Development of Integrated Alstom Gasification Simulator for Implementation Using DCS CS3000

In this paper we explore the development of integrated plant simulator that integrates MATLAB as an engine and DCS CS3000 as an industrial controller. It works realtime and online like real industrial control plant scheme. For industrial practicians like operator and engineer, this simulator is very useful as an operator training or control educational tools and can be used to implement loop pairing selection and tune the controller parameters. As a requirement of controlling using DCS, this paper provides integrated analysis tools for loop pairing by implementation relative gain array (RGA) method and decentralized relative gain (DRG). Plant case for this simulator is Alstom gasification.

Ultrasonic tomography for reinforced concrete inspection using algebraic reconstruction technique with Iterative Kaczmarz method

Non-destructive testing for evaluating the safety and quality of concrete structures is highly needed in the field of construction and civil engineering. The imaging of concrete structures is still, however, considered to be a very challenging task due to the non-homogeneous properties of the material. In order to address this challenge, this paper presents a non-destructive testing method using ultrasonic wave to identify the internal structure of a concrete sample. A combination of signal smoothing and threshold method was used as signal processing tool for interpreting and analyzing the ultrasonic waveform from the concrete sample. The Algebraic Reconstruction Technique with Iterative Kaczmarz method was then applied as the image reconstruction algorithm. The results from our experiment show that the ultrasonic tomography based on the Iterative Kaczmarz method successfully distinguish embedded steel rod from the rest of materials in the concrete. This paper thus illustrate the proven reliable of the proposed method for testing concrete structures.

Fluid flow velocity measurement using dual-ultrasonic transducer by means of simultaneously transit time method

An ultrasonic flowmeter based on transit time method (USM-TT) is often used to obtain high accuracy measurements of gas flow velocity. The working principle of an USM-TT is based on the measurements of two times of flight (TOF) of ultrasonic waves that propagate toward opposite direction. In particular, both TOFs are measured sequentially under the assumption that there exists no sudden change of flow velocity during the sampling period. When such an assumption is not fulfilled, the obtained velocity can not be assumed to be the true data. To overcome the above problem, we propose an alternative method, namely simultaneously transit time (STT), which is able to obtain both of TOFs for the same flow velocity by employing dual ultrasonic transducers that transmit and receive ultrasonic wave simultaneously. For experimental validation, two ultrasonic modules which have a transmitter and a receiver ultrasonic inside are utilized as ultrasonic transducer. In addition, microcontroller is employed for data acquisition and activating the ultrasonic devices. Based on the obtained experimental data, we found that the STT method effectively reduces the sampling period required in the conventional method up to almost 50%. Thus, because TOFs are obtained for the same flow velocity, the probability of the sudden change of flow velocity during the sampling period can be diminished.

Boundary potential distribution in rectangular object based on data collection system

One of the problems that exist in the EIT is less sensitive of boundary potential changes due to changes in the parameters object at a distance from the edge. This boundary potential distribution pattern is determined by a given current injection pattern. Thus need to know the combination of current injection patterns and methods of data collection potential corresponding boundary. The data collection system should determine the value of sensitivity and have the certain ability to detect changes in the object parameters. In this study, the data collection system will be tested on a rectangular-shaped object. Forward model analysis toward the pattern of boundary potential is conducted. The results showed that the pattern of boundary potential should be considered in reconstruction process except a large sensitivity.

Image reconstruction of time domain diffuse optical tomography for quality control on seed potatoes

The purpose of this study is to apply model based iterative reconstruction method on a ring array diffuse optical tomography system based on mean time of flight. This study was conducted on numerical object that represents the real condition of seed potatoes. The object was illuminated by the near infrared source from 12 positions on objects boundary. A set of near infrared detector are placed on the periphery of the object and it measures the intensity of propagated light. In the simulation, we vary the condition of object then we analyze the correlation between simulated and reconstructed image. The result of this study indicated that time domain-diffuse optical tomography is promising for quality control on seed potatoes.

Summation convolution filtered back projection and algebraic reconstruction technique for ring array ultrasound tomography based on time of flight

Purpose of the study is to apply SCFBP and ART methods on a ring array ultrasound tomography system based on time of flight. The study was conducted with numerical and experimental object by 16 positions in circular phantom. The data set of ring array was rearranged and interpolated into parallel scheme to reconstructed by SCFBP and ART methods. The result indicated that rearrangement and interpolation is feasible to use SCFBP methods, improve speed and reconstructed image quality on ART methods.

The influence of the tape-core layer number of fluxgate sensor to the demagnetization factor

This paper explains the influence of the tape-core layer number to the demagnetization factor of a fluxgate sensor. The demagnetization factor was calculated based on the physical dimension, the self-inductance of coil without inserting the core (L<inf>no_core</inf>) and by inserting the core (L<inf>core</inf>) of the sensor. The calculated demagnetization factor to pick-up coil configurations of 2×80 are proportional, 0.51, 0.82, 1.15, and 1.40}10⁻³ whereas the one to pick-up coil configurations of 2}20 are 1.02, 1.58, 2.23, and 2.78}10⁻³, each of which uses the tape-core layer number 1,2, 3, and 4 respectively.

The synthesis of Fe3O4/MWCNT nanocomposites from local iron sands for electrochemical sensors

The aim of this research is producing the electrochemical sensor, especially for working electrodes based on the nanocomposites of multi-walled carbon nanotube (MWCNT) and magnetite (Fe3O4) nanoparticles from iron sands. The sonochemical method by ultrasonic horn was successfully used for the synthesis of the nanocomposites. The characterizations of the sample were conducted via X-Ray Diffractometer (XRD), Fourier Transform Infra-Red (FTIR) Spectrometer, Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Brunauer-Emmett-Teller (BET) method for surface area, Vibrating Sample Magnetometer (VSM) and Cyclic Voltammetry (CV). The analysis of X-Ray Diffraction (XRD) pattern showed two phases of crystalline, namely MWCNT and Fe3O4, peak of MWCNT comes from (002) plan while peaks of Fe3O4 come from (2 2 0), (3 1 1), (4 0 0), (4 2 2), (5 1 1), and (4 4 0) plans. From XRD data, MWCNT has a hexagonal structure and Fe3O4 has inverse spinel cubic structure, respectively. The FTIR spectra revealed that the functionalization process of MWCNT successfully generated carboxyl and carbonyl groups to bind Fe3O4 on MWCNT surfaces. Moreover, the functional groups of Fe-O bonding that showed the existence of Fe3O4 in the nanocomposites were also detected in those spectra. Meanwhile, the SEM and TEM images showed that the nanoparticles of Fe3O4 attached on the MWCNT surface and formed agglomeration between particles due to magnetic forces. Through Brunauer-Emmett-Teller (BET) method, it is identified that the nanocomposite has a large surface area 318 m2/g that makes this material very suitable for electrochemical sensor applications. Moreover, the characterization of magnetic properties via Vibrating Sample Magnetometer (VSM) showed that the nanocomposites have superparamagnetic behavior at room temperature and the presence of the MWCNT reduced the magnetic properties of Fe3O4. Lastly, the electrochemical characterization with Cyclic Voltammetry (CV) proved that Fe3O4/MWCNT nanocomposites with iron sands as the starting materials have high sensitivity and serve as excellent electron transfer materials. Based on the results of the research, the Fe3O4/MWCNT nanocomposites from iron sands are much recommended for electrochemical sensor.The aim of this research is producing the electrochemical sensor, especially for working electrodes based on the nanocomposites of multi-walled carbon nanotube (MWCNT) and magnetite (Fe3O4) nanoparticles from iron sands. The sonochemical method by ultrasonic horn was successfully used for the synthesis of the nanocomposites. The characterizations of the sample were conducted via X-Ray Diffractometer (XRD), Fourier Transform Infra-Red (FTIR) Spectrometer, Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Brunauer-Emmett-Teller (BET) method for surface area, Vibrating Sample Magnetometer (VSM) and Cyclic Voltammetry (CV). The analysis of X-Ray Diffraction (XRD) pattern showed two phases of crystalline, namely MWCNT and Fe3O4, peak of MWCNT comes from (002) plan while peaks of Fe3O4 come from (2 2 0), (3 1 1), (4 0 0), (4 2 2), (5 1 1), and (4 4 0) plans. From XRD data, MWCNT has a hexagonal structure and Fe3O4 has inverse spinel cubic structure, respectively. The FTIR spectra revea...