Horizon 2020 SME Instrument

Horizon 2020 SME Instrument

With an innovation score of 13.91 of 15 possible, Signal Analysis Lab is granted Horizon 2020 SME Instrument phase 1 support. SME Instrument is an EU program for small and medium-sized enterprises to get funding for breakthrough innovation projects. The SME instrument will boost fast company growth and market-creating innovation thanks to staged financing and ramped up business acceleration services.

Paper on signal analysis of blood pressure

In January 2018, a cooperation between Signal Analysis Lab, St. Olav's University Hospital, and NTNU led to the paper "Instantaneous Frequencies of Continuous Blood Pressure a Comparison of the Power Spectrum, the Continuous Wavelet Transform and the Hilbert–Huang Transform" in Advances in Data Science and Adaptive Analysis. It is written by Kathrine Knai, Signal Analysis Lab employee Geir Kulia, Dr Nils Kristian Skjærvold, and Professor Marta Molinas.

Abstract

Continuous biological signals, like blood pressure recordings, exhibit nonlinear and nonstationary properties which must be considered during their analysis. Heart rate variability analyses have identified several frequency components and their autonomic origin. There is need for more knowledge on the time-changing properties of these frequencies. The power spectrum, continuous wavelet transform and Hilbert–Huang transform are applied on a continuous blood pressure signal to investigate how the different methods compare to each other. The Hilbert–Huang transform shows high ability to analyse such data, and can, by identifying instantaneous frequency shifts, provide new insights into the nature of these kinds of data.

The paper can be read here.

Paper on control of wave energy converters

In July 2017, Signal Analysis Lab employee Paula B. Garcia Rosa presented her paper at the 20th World Congress of the International Federation of Automatic Control. The paper was written with Geir Kulia from Signal Analysis Lab, Prof. John Ringwood from National University of Irland, and Prof. Marta Molinas from NTNU.

Abstract

Passive loading is a suboptimal method of control for wave energy converters (WECs) that usually consists of tuning the power take-off (PTO) damping of the WEC to either the energy or the peak frequency of the local wave spectrum. Such approach results in a good solution for waves characterized by one-peak narrowband spectra. Nonetheless, real ocean waves are non-stationary by nature, and sea wave profiles with different spectral distribution occur in a specific location over time. Thus, the average energy absorption of passively controlled WECs tends to be low. In this paper, we propose a real-time passive control (PC) based on the Hilbert-Huang transform (HHT), where the PTO damping is time-varying and tuned to the instantaneous frequency of the wave excitation force. The instantaneous frequency is calculated by using the HHT, an analysis method for nonlinear and non-stationary signals that rely on the local characteristic time-scale of the signal. A performance comparison (in terms of energy absorption) of the proposed solution with the passive loading method is presented for a heaving system, in a variety of wave spectra. It is shown that a performance improvement of up to 21%, or 65%, is obtained for the proposed PC scheme, when it is compared to passive loading tuned to the energy, or the peak frequency of the spectrum, respectively. Real ocean waves off the west coast of Ireland are adopted in the simulations.
 

The paper can be read here.

Paper on harmonic propagation

In June 2017, Signal Analysis Lab published a paper with Prof. Molinas, Prof. Lundheim and Prof. Fosso from NTNU at the International Conference on Clean Electrical Power.

Schematics-of-the-microgrid-at-RUB-College-of-Science-and-Technology.png

The paper presents an analytical method developed to explain the mechanism of harmonic transfer between the ac and dc sides of a single-phase inverter in a PV microgrid. The model explains how the feed-forward of the current from the ac side of the PV-inverter into the control system, causes even harmonics on the dc voltage. It further shows how the controller's feedback of the dc bus voltage carrying even harmonics results in odd harmonics on the ac side of the PV-inverter. This harmonic propagation model is verified with a simulation of the PV microgrid system. The results of this simulation study provide consistency by verifying those odd harmonics on the ac voltage causes even harmonics on the dc bus, and that even harmonics on the dc bus again causes more odd harmonics on ac voltage.

The paper can be found here.

Technoport

On 8 March 2017, we attended Technoport in Trondheim, displaying the mind-controlled drone together with NTNU. Read more here.

 Photo: Technoport

Photo: Technoport

Soft funding

Soft funding

In December 2016, we got one million Norwegian kroner in support by the Research Council of Norway's program Forny Student. Read more here!