Publications of 2020 

Conference papers 2020

"Sub-Millisecond Transient Analysis With Multi-Point Measurement In Weak Grids"

A. Matthee, N. Moonen, F. Leferink.

Abstract:  Peak loads determine the rated capacity of islanded grid power supplies. This often results in non-optimal running conditions in terms of cost, efficiency or size footprint. Presented in this paper is a method of in-depth analysis of very fast sub-millisecond transient behaviour performed between sub-systems and supply in a low-inertia grids. Using this method, time domain measurements can be analysed to potentially achieve electromagnetic compatibility. Synchronised current and voltage measurements are possible, with offsets in the sub-milliseconds and high sample rates of tens of Mega-samples per second. A demonstration of a weak grid is presented showing effects of linear and non-linear loads on the supply source and power quality.

"Continuous Electromagnetic Emission Measurement Setup with Antenna Position Tracking"

D. Pokotilov, R. Vogt-Ardatjew, T. Hartman, F. Leferink.

Abstract: For measuring the maximum electromagnetic emissions around equipment many test methods use the frequency domain, traditionally using a super-heterodyne test receiver. However, for large equipment under test the frequency domain method is very time consuming when the measurements are performed at low frequencies, below 150 kHz, where small bandwidth and thus long measurement time is needed. Timedomain measurements are now replacing the traditional superheterodyne receivers, but the commercial time-domain receivers still use a first mixer stage. However, at low frequencies, low cost digitisers can do the same job directly in the baseband. Using fast signal processing, this method allows to continuously measure the radiated magnetic field around the equipment under test. Combined with position tracking, this allows to identify areas of maximum emissions very fast. These positions are then used to obtain a more detailed spectral analysis of emissions by increasing the measurement time over those spots. In result, the whole measurement procedure can be significantly optimized by spending less time over areas of lower interest, and putting more focus on areas of potentially high emission levels. This paper presents the concept as well as an experimental comparison of three antenna movement approaches satisfying the NRE01 and RE101 radiated emissions measurement procedures.

"SPICE Simulation of Modal Impedances in Automotive Powertrains under Different Operating Conditions"

L. Wan, A. Hamid, F. Grassi, G. Spadacini, S. A. Pignari

Asbract: The spread of information-communication technology (ICT) devices in full and/or hybrid electric vehicles is posing increasing issues about coexistence between communication and electric power systems. Particularly, under different operating conditions, the time-variant and nonlinear behavior of the involved power-electronic devices may cause detrimental electromagnetic interference (EMI) effects for onboard ICT devices. The use of passive or active EMI filters can mitigate EMI, yet their effective design requires the knowledge of the actual modal impedances of the involved components. With the final objective to support EMI filter design, in this work, the frequency response of the common mode (CM) and differential mode (DM) impedances of a complete automotive power train is investigated under different operating conditions. Moreover, both low-frequency functional aspects and high-frequency parasitic effects are considered and modelled properly.

"Reduction of Conducted Emissions in DC/DC Converters with FPGA-based Random Modulation"

H. Loschi, R. Smolenski, P. Lezynski, W. El Sayed, D. Nascimento

Abstract: FPGA became a low-cost platform providing the possibility to design new ”EMC friendly” control techniques for power electronics. However, some of the functions required in the power electronic control system are difficult to implement in FPGA. The main challenges are connected to the fixedpoint operation, and the need to adjust the dynamic range of numbers. To provide design insights on this topic, the paper presents an FPGA-based random modulation technique intended for DC/DC converter for harmonic reduction. The presented random technique is compared with deterministic PWM in terms of harmonics reduction and FPGA hardware resources. The theoretical algorithms, hardware details, and experimental results are presented and discussed.

"An Open Source, FPGA-Based Bit Error Rate Tester for Serial Communications" 

M. J. Basford, A. E. Pena-Quintal, S. Greedy, M. Sumner, D. W. P. Thomas.

Asbtract: This paper discusses the design of a FPGA-based Bit Error Ratio (BER) measurement system in a serial communication link under electromagnetic emissions. The BER measurement is an important figure for the reliability of digital communication systems. Generally, the equipment involved to measure BER is prohibitively expensive. This paper demonstrates the design, construction and verification of an Open Source System (OSS), with all design files being made freely accessible to the public for use in general or highly specialized BER measurements. The methods used for programming the Hardware Description Language (HDL) modules were done as simple as possible to facilitate easy integration into experiments for academics with limited experience in HDL usage.

"Data Links Modelling under Radiated EMI and its Impact on Sampling Errors in the Physical Layer" - Accepted for publication

A. E. Pena-Quintal, M. J. Basford, K. Niewiadomski, S. Greedy, M. Sumner, D. W. P. Thomas.

Abstract: This paper deals with the effects of radiated EMI on serial communication links using software modelling with particular emphasis on the physical layer. The effect of EMI in data links is an important problem to solve in many harsh environments such as the automotive and the transport sector as well as communications, in fact the EMI effect is able to produce sampling errors in digital/binary operations. Currently binding standards prefer the analysis in frequency domain to account for EMI impact, however when dealing with data links, time domain analysis might report useful information, therefore a link between those two is needed. The cable models are developed using SACAMOS modelling software, taking into  consideration the frequency parameters. The model can be used on almost any SPICE simulator to analyse the effect of EMI. The simulations performed in this research are verified on a real laboratory experiment in order to demonstrate the capabilities of SACAMOS.

"Power Quality Analysis (0-2kHz) in DC/DC  Converters under Steady State and Transient  Conditions" - Accepted for publication

A. D. Khilnani, K. Niewiadomski, C. Rose,  M. Sumner, D. W. P. Thomas, E. Ballukja, L. Sandrolini, A. Mariscotti.

Abstract: The aim of this paper is to understand the effects  of low frequency (0-2kHz) conducted emissions on power quality from a microgrid based DC/DC converter under steady state and transient loading conditions. The experimental data obtained from the lab set-up is analysed using Fast Fourier Transform and low frequency sinusoidal disturbance indices for input DC voltage and current are calculated. The results show that power quality of a DC/DC converter with varying loads does get affected by the conducted emissions, but the indices obtained cannot be quantified due to lack of standards for DC power quality. The indices decrease with increasing load and have a non-zero value at no-load condition. Further, the calculated results from amplitude probability distribution are in agreement with the indices as well.

"Versatile High-Sample Frequency Power Quality Measurement Device"

A. Matthee, N. Moonen, F. Leferink.

Abstract: Rapidly advancing technology has seen the adoption of non-linear loads which may be considered improving efficiency and decreasing cost. Unfortunately this advance of technology often exceeds the measures to control the unforeseen effects of systems or unwanted interference between multiple manufacturer's devices. In this paper a relatively modern building, with a common experience of conducted electromagnetic interference including power quality problems such as harmonic distortion of the supply, is discussed. A system is developed to monitor the power quality of the mains in various locations and aid in identifying the extent of the electromagnetic interference. With high sampling frequency and synchronising of measurement data between various locations accurate within millisecond scale in the power distributed user network, the extent of conducted emission events especially sub millisecond range, is analysed.

Journal papers 2020

"FPGA-Based System for Electromagnetic Interference Evaluation in Random Modulated DC/DC Converters"

H. Loschi, P. Lezynski, R. Smolenski, D. Nascimento, W. Sleszynski

Abstract: Field-Programmable Gate Array (FPGA) provides the possibility to design new “electromagnetic compatibility (EMC) friendly” control techniques for power electronic converters. Such control techniques use pseudo-random modulators (RanM) to control the converter switches. However, some issues connected with the FPGA-based design of RanM, such as matching the range of fixed-point numbers, might be challenging. The modern programming tools, such as LabVIEW, may facilitate the design process, but there are still fixed-point operations and limitations in arithmetic operations. This paper presents the design insights on the FPGA-based EMC friendly control system for DC/DC converter. Probability density functions (PDF) are used to analyse and improve pseudo-random algorithms. The theoretical algorithms, hardware details and experimental results are presented and discussed in terms of conducted electromagnetic interference emission. web builder