Conference Papers & Presentations (Electrical, Electronic and Computer Engineering)

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Now showing 1 - 15 of 15

Multivariate regression for electricity load forecasting in power systems
(Scanditale AB, 2024) Joy, E.R.; Bansal, Ramesh C.; Ghenai, C.; Gryazina, E.; Kumar, R.; Sujil, A.; International Conference on Applied Energy (15th : 2023 : Doha, Qatar)
The development of smart grids in power system necessitates the need for forecasting the electricity load for the safe and economic functioning of electricity markets. A case study has been carried out considering a city’s electricity load data using Multivariate Regression model. An input database of the model is generated taking into account of peak and off-peak hours based on maximum and minimum load data obtained from the utility operator. The characteristics of the electricity load over the whole year have been primarily analyzed to obtain a better intuition on the load behavior. In this context, the information in the form of temperature, days, different time duration i.e., peak and off-peak hours and past load data have been given as input to the regression model. The accuracy of the method has been evaluated using Root Mean Square Error (RMSE). The results of the adapted model have been compared with Neural Network, Ensemble and Kernel methods.
An evolutionary game model for EV and charging station adoption
(Scanditale AB, 2024) Yu, Gang; Ye, Xianming; International Conference on Applied Energy (15th : 2023 : Doha, Qatar); u20801540@tuks.co.za
Electric vehicles and charging stations are pivotal tools in the endeavor to decarbonise the transportation system. The connection between the adoption of electric vehicles and the deployment of charging stations is widely recognised as a "chicken-and-egg" dilemma. This term describes a situation where the low adoption of electric vehicles impedes the installation of charging stations, and conversely, the limited availability of charging stations dampens drivers' enthusiasm to switch to electric vehicles. To gain insights into this intricate relationship between consumers' choices regarding electric vehicles and infrastructure investors' decisions on charging station expansion, this study employs an evolutionary game model. This model not only captures the dynamic interactions involved but also considers the internal and external factors that influence these decisions. Leveraging this model, this paper analyses the impact of incentive policies on the adoption rates of electric vehicles and charging stations.
Oscillation-based test in a CCII-based bandpass filter
(Institute of Electrical and Electronics Engineers, 2017-02) Petrashin Pablo; Toledo, Luis; Lancioni, Walter; Osuch, Piotr Jan; Stander, Tinus
Oscillation based testing (OBT) has proven to be a simple yet effective VLSI test for numerous circuit types. In this work, OBT is applied to test Second-generation Current Conveyor (CCII) based filters for the first time. Adopting a CCII-based band pass filter as a case study, it is shown that OBT can be implemented with a minimally intrusive switched feedback loop to establish the oscillator. Exhaustive fault simulation indicates 98.11% detection of possible short circuit and 100% detection of possible open circuit faults in the circuit under test, in both 0.35μm and 1.2μm CMOS technology nodes.
Active enhanced tunable high-Q on-chip E-band resonator in commercial 130nm BiCMOS
(Institute of Electrical and Electronics Engineers, 2015-12) IEEE International Microwave and RF Conference (2015 : Hyderabad, India); Singh, Nishant; Stander, Tinus
A simulation study of a high-Q resonator in a commercial 130nm SiGe BiCMOS process for E-band frequencies is presented. The resonator is a planar quarter-wave microstrip resonator that uses a HBT based negative resistance circuit to counter losses and enhance the unloaded Q-factor. Using 3D EM (FEM) and circuit co-simulation, enhanced unloaded Q-factors of up to 892 are shown at a frequency of 83.5 GHz compared to the unenhanced unloaded Q-factor of 7. The negative resistance circuit sufficiently compensates for low Q-factors of the planar resonator and the varactor. The resonator is also shown to be continuously tunable in frequency from 82 to 84 GHz, and in unloaded Q-factor from 7 to 892, whilst maintaining unconditional stability in all tuning states.
A flexible Pcell-driven design flow for mm-wave on-chip passives
(Institute of Electrical and Electronics Engineers, 2015-12) tinus.stander@ieee.org; IEEE International Microwave and RF Conference (2015 : Hyderabad, India); Stander, Tinus
On-chip EM modeling at mm-wave frequencies requires design methods that incorporate the layout and verification macros of IC EDA tools with parameterized EM CAD. We propose a novel, flexible design flow for 3D EM modeling of BEOL structures that allows for parameterized design of BEOL structures using Pcell elements as seed, thereby reducing the time required to generate the full simulation model in EM CAD. The method is illustrated by the co-design of a 94 GHz directional coupler.
Development, simulation and construction of cost-effective GTEM cells
(Institute of Electrical and Electronics Engineers, 2013-04) International Conference on Radioelektronika, (23rd : 2013 : Pardubice, Czech Republic); Sinha, Saurabh; Stander, Tinus
Gigahertz transverse electromagnetic (GTEM) cells are used extensively in industry for testing the impact of defined E-fields on devices sensitive to electromagnetic interference. Compared to anechoic chambers, GTEM cells are small, inexpensive and require less powerful amplifiers to achieve the same field strength. This paper presents the design, simulation and qualification of a compact GTEM cell capable of generating field strengths in excess of 600 V/m over a 20 × 20 × 15 cm test cavity, whilst being less than 2.2 × 1.3 × 1 m in total size. Specific hybrid FEM-MLFMM simulation strategies are provided to examine high power device characteristics prior to manufacturing, including accurate modelling of absorber materials. Practical notes on manufacturing and qualification are also presented.
An on-chip post-production tunable group delay equaliser
(Institute of Electrical and Electronics Engineers, 2014) International Conference on Actual Problems of Electron Devices Engineering (APEDE) (2014 : Saratov, Russia); Osuch, Piotr Jan; Stander, Tinus
A design method for distributed element on-chip post-production tunable group delay equalising networks is presented. It is shown that a number of adjustable Darlington C-sections can be used to equalise the group delay of an arbitrary network. The C-sections are implemented in an IBM 0.13 μm BiCMOS process as complementary microstrip slotline-stub all-pass structures and modified to provide post-production tunability. The group delay ripple of a theoretical second-order Butterworth bandpass filter, cascaded with the synthesised all-pass network, is reduced by 43% as proof of concept.
L-band tapered-ridge SIW-to-CPW transion
(Institute of Electrical and Electronics Engineers, 2014) International Conference on Actual Problems of Electron Devices Engineering (APEDE) (2014 : Saratov, Russia); Smith, James Nathan; Stander, Tinus
A tapered ridge transition between coplanar waveguide and substrate-integrated waveguide is presented. The taper is implemented through staircase metallization across 10 layers of conventional RF substrate with sidewall expansion and upper cut-out using Vivaldi-type exponential tapers. Fractional bandwidth of 36% is achieved in the L-band, with insertion loss of 0.5 dB and return loss of 15 dB.
A comparison of basic 94 GHz planar transmission line resonators in commercial BiCMOS back-end-of-line processes
(Institute of Electrical and Electronics Engineers, 2014) tinus.stander@ieee.org; International Conference on Actual Problems of Electron Devices Engineering (APEDE), 2014: Saratov; Stander, Tinus
A comparative simulation study of planar 94 GHz resonators in a typical BiCMOS BEOL stack-up is presented, with the effect of chip passivation included. It is shown that Q-factors of between 3 and 15 can be obtained, depending on transmission medium and ground plane layer choice. Straight half-wavelength and shorted quarter-wavelength microstrip resonators are shown to outperform CPW, GCPW and hairpin resonators, with highest Q-factors obtained where the lowest available metallization layer is used as ground plane. Q-factors of above 10 may also be achieve in the absence of any ground plane in CPW, which may be implemented in processes (such as GaAs or GaN) where multiple metallization layers are not readily available.
A frequency agile switched delay line slow-wave
(Institute of Electrical and Electronics Engineers, 2013-04) International Conference on Radioelektronika, 23rd : 2013 : Pardubice, Czech Republic; Sinha, Saurabh; Bhana, V.B. (Vishal); Stander, Tinus
A mm-wave BiCMOS back-end metallization switched delay line frequency agile filter is presented. Miniaturization of the delay lines is achieved by using slow-wave propagation modes on shielded CPWs, with a standard BiCMOS process transistors used as on-chip switching elements. A first-order filter is presented, with simulation results indicating one transmission band at 40.4 GHz of 22.8 % relative bandwidth and insertion loss of –12.25 dB, with the other transmission band at 47.55 GHz with a 23.79 % relative bandwidth and insertion loss of –13.66 dB. Both bands feature below -15 dB input reflection loss. The paper further establishes the potential for shielded CPW transmission lines for the design of complex passive devices on the back-end metallization of various semiconductor technologies.
Entrepreneurship as an IEEE workforce development theme
(Institute of Electrical and Electronics Engineers, 2013) IEEE Global Humanitarian Technology Conference (GHTC) (2013 : San José, California, United States of America); Sinha, Saurabh; Stander, Tinus
The IEEE is currently planning an extensive workforce development (WFD) programme through its volunteer and associated networks. Together with environmental scans, potential learning areas and contributing partners are being solicited. The Institute of Physics has an established workshop in Entrepreneurship for Scientists and Engineers, which may partially fulfil this role. This paper describes the format and content of this workshop, constructively evaluating it keeping in mind metrics relating to WFD. Future value-adds for IEEE involvement are identified.
Waveguide power combiner with adjustable amplitude and phase response
(Institute of Electrical and Electronics Engineers, 2013) International Conference on Radioelektronika (23rd : 2013 : Pardubice, Czech Republic); Stander, Tinus; Sinha, Saurabh
Maximum gain from combining multiple high-power signals is achieved by equalising both the amplitude and phase of the combination. Achieving in-phase and equal amplitude power combining with amplifiers of unequal gain and group delay requires compensation by means of delay lines and external gain adjustment. This paper proposes an improved X-band waveguide H-plane cross-guide combiner which allows for post-production adjustment of the combining power ratio, as well as equalization of the phase responses. This adjustment capability allows for mass-production of the combiner, irrespective of the exact phase and gain characteristics of individual amplifiers. The nominally equal amplitude combining ratio is shown to be adjustable by ±0.4 dB over 400 MHz bandwidth at X-band, whilst the phase difference may be altered, independently from the amplitude response, from -2.52° to +2.52°. Good agreement is found between simulated and measured results.
Inactivating pathogenic micro-organisms through microwave sterilization technology
(Institute of Electrical and Electronics Engineers, 2013-05) Du Preez, Jaco; International Symposium on Electrodynamic and Mechatronic System (SELM) 2013 : Opole-Zawiercie; Sinha, Saurabh; Stander, Tinus
Microwave heating as a means of inactivating pathogenic micro-organisms in commercially produced food products in sterilization and pasteurization processes is discussed in this paper. The physics of a microwave heating system was explored and compared to the more widely used retorting processes. Existing and developing microwave sterilization processes were researched and are discussed here.
Inline Ka-band transitional combline / evanescent-mode filter in conventional RF substrate using grounded vias
(Institute of Electrical and Electronics Engineers, 2015-09) IEEE Africon (2015 : Addis Ababa, Ethiopia); Stander, Tinus
The Ka-band is considered a viable band for future 5G backhaul links. Planar filters in this frequency range have low aspect ratios for substrates thicker than 10 mil, since the required 50 Ω line width becomes comparable to a guided wavelength. This paper proposes the use of grounded through-hole plated vias as transitional combline / evanescent-mode resonators. The principle is demonstrated with a 4th order, 27.5 – 29.5 GHz filter in a conventional 32 mil thickness RF substrate. The simulated filter features below 2 dB insertion loss across the band and occupies 3.8 x 1 mm board space.
A review of key development areas in low-cost packaging and integration of future E-band mm-wave transceivers
(Institute of Electrical and Electronics Engineers, 2015-09) tinus.stander@ieee.org; IEEE Africon (2015 : Addis Ababa, Ethiopia); Stander, Tinus
With an ever increasing number of broadband applications in sub-Saharan Africa, mm-wave point-to-point networking has the potential to fill a niche in communications network architectures. Widespread adoption of this technology would benefit from conventional RF soft substrate integration and packaging, as opposed to system-on-chip or thick film processes. A review on the state-of-the-art in E-band soft substrate systems reveals significant reliance on MMICs. We propose that hybrid integration of active devices with off-chip passives, as well as better integration of active components in SIW, will lead to better performing E-band systems in soft substrates. Specific enabling techniques from the microwave domain are identified.

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