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In this paper, a textile-based strain sensor has been developed to create a respiration belt. The constituent materials and the knitted structure of the textile sensor have been specifically selected and tailored for this application. Electromechanical modeling has been developed by exploiting Peirce's loop model in order to describe the fabric geometry under static and dynamic conditions. Kirchhoff's node and loop equations have been employed to create a generalized solution for the equivalent electrical resistance of the textile sensor for a given knitted loop geometry and for a specified number of loops. A laboratory test setup was built to characterize the prototype sensor and the resulting equivalent resistance under strain levels up to 40%, and consistent resistance response levels have been obtained from the sensor which correlate well with the modelled data. Production of the respiration belt was realized by bringing together knitted sensor and a relatively inelastic textile strap. Both machine simulations and real-time measurements on a human subject have been performed in order to calculate average breathing frequencies under different static and dynamic conditions. Also, different scenarios have been performed, such as slow breathing and rapid breathing. The sensory belt was located in either the chest area or in the abdominal area during the experimental measurements and the sensor yielded a good response under both static and dynamic conditions. However, body motion artefacts affected the signal quality under dynamic conditions and an additional signal-processing step was added to eliminate unwanted interference from the breathing signal.Index Terms-Breathing frequency, conductive yarn, knitted sensor, respiration belt, silver-coated nylon yarn, textile-based strain sensor, electro-mechanical modelling.

Abstract-High penetration of photovoltaic (PV) inverters in low voltage (LV) distribution network challenges the voltage stability due to interaction between multiple inverters and grid. As the main objective is to provide more power injection from VSC-based PV inverters, grid stability, reliability and power quality must be maintained or improved by adding cooperative control features to the grid-connected inverters. This paper first gives an overview of bilateral impacts between multiple distributed generations (DG) and grid. Regarding of these impacts, recent advances in static grid voltage support functionalities to increase penetration level are compared considering voltage rise limitation. Steady-state simulation study is realized in PSCAD/EMTDC and the results are discussed in terms of total generation efficiency.

Admissible range of grid voltage is one of the\ud strictest constraints for the penetration of distributed\ud photovoltaic (PV) generators especially connection to low\ud voltage (LV) public networks. Voltage limits are usually fulfilled\ud either by network reinforcements or limiting of power injections\ud from PVs. In order to increase PV penetration level further, new\ud voltage support control functions for individual inverters are\ud required. This paper investigates distributed reactive power\ud regulation and active power curtailment strategies regarding the\ud development of PV connection capacity by evaluation of reactive\ud power efforts and requirement of minimum active power\ud curtailment. Furthermore, a small scale experimental setup is\ud built to reflect real grid interaction in the laboratory by\ud achieving critical types of grid (weak and sufficiently stiff).Peer ReviewedPostprint (published version

Grid voltage rise and thermal loading of network\ud components are the most remarkable barriers to allow high\ud number of distributed generator (DG) connections on the\ud medium voltage (MV) and low voltage (LV) electricity networks.\ud The other barriers such as grid power quality (harmonics,\ud voltage unbalance, flicker etc.) and network protection\ud mechanisms can be figured out once the maximum DG\ud connection capacity of the network is reached. In this paper,\ud additional reactive power reserve of inverter interfaced DGs is\ud exploited to lower the grid voltage level by means of locationadaptive\ud Q(U) droop function. The proposed method aims to\ud achieve less grid voltage violations thus more DG connection on\ud the electricity distribution networks can be allowed.Peer ReviewedPostprint (published version