Critical Parameters for Mutual Inductance Between Rogowski Coil and Primary Conductor

We present the results of an analytical study aimed at characterizing the critical parameters affecting the mutual inductance M between Rogowski coils and primary conductors. The analysis is based on the method of the mutual partial inductances and it is applied to various case studies. Calculations are carried out for Rogowski coils having a few turns, hundreds, and even thousands of turns with uniform and nonuniform windings. We also provide the results of an experimental analysis performed on a Rogowski coil with a small number of turns for comparison with the proposed technique

Critical parameters for mutual inductance between Rogowski coil and primary conductor

We present the results of an analytical study aimed at characterizing the mutual inductance M of Rogowski coils for generic paths of the primary wire and for nonuniform windings. In order to obtain such data, we performed a series of calculations based on the method of the mutual partial inductances and on the application of the Biot-Savart-Laplace law. Finally, we discuss the role of some critical parameters affecting M

Analisi e misura di campi elettromagnetici in materiali compositi e dispositivi elettrici speciali

La tesi riguarda la misura ed analisi di campi elettromagnetici nell'intervallo di frequenze che va da pochi kHz ad alcune centinaia di MHz al fine di caratterizzare il comportamento magnetico di strutture composite costituite da elementi risonanti e le emissioni di campi elettromagnetici in presenza di fenomeni impulsivi. Partendo dai risultati di recenti studi sul comportamento magnetico di strutture composite viene presentata un'analisi teorica, sperimentale e di modello che mira a dimostrare come l'espressione del parametro permeabilità magnetica effettiva μeff ottenuta per una configurazione a "singola cella" consenta di caratterizzare il comportamento magnetico di una matrice estesa di risonatori. Sono valutate le ipotesi di validità del setup ed è mostrato come la media spaziale può influire sulla valutazione del parametro μeff. Vengono riportati i risultati sperimentali ottenuti per vari prototipi di tipo "swiss-roll" ed "R-L-C". L'analisi di campi elettromagnetici impulsivi è stata effettuata per un prototipo di lanciatore di tipo "railgun". L'analisi ha lo scopo ci investigare le emissioni connesse al funzionamento del lanciatore. La tesi riporta il modello circuitale utilizzato per lo studio del transitorio di corrente in bassa frequenza del circuito ed un'analisi sia sperimentale che di modello sviluppata allo scopo di evidenziare il comportamento alle alte frequenze. Sono descritti vari esperimenti condotti in differenti modalità operative. I risultati sono riportati in forma grafica e discussi

Design of Digital Integrator for Rogowski Coil Sensor

The goal of this thesis is to create a well performed digital Rogowski coil integrator on PC for later implementation on FPGA, and the final filter is applied with fixed point arithmetic. Integrator’s design and optimization based on the specification provided by the company. During the implementation, the constraints of the hardware should be taken into account, and the design method needs to be verified by simulations and practical experiments and tests. There are two design phases to implementing the filter. The first phase is software implementation, the integrator is realized by creating the MATLAB and C models. The other phase is hardware realization. By software application, the filter could be simu-lated with targeted test benches. After the software application is verified, hardware implementation could be carried out if it is necessary. In this thesis, RTL model is de-rived from the C model via translating it with VHDL. Afterward, the integrator is im-plemented on FPGA board for practical field tests. From the tests, the validity, practicability of the Rogowski integrator have to be veri-fied from the perspective of both functionality and performance. The software imple-mentation of the integrator is capable of filtering different kinds of the input signals with reasonable and acceptable outputs. Meanwhile, in the practical application, the integrator performed well when dealing with various earth fault cases. All, in brief, this Rogowski integrator has to satisfy the standard of the design specification

Micro-manufactured Rogowski coils for fault detection of aircraft electrical wiring and interconnection systems (EWIS)

Aircraft wiring failures have increased over the last few years resulting in arc faults and high-energy flashover on the wiring bundle, which can propagate down through aircraft Electrical Wiring and Interconnect Systems (EWIS). It is considered cost prohibitive to completely rewire a plane in terms of man hours and operational time lost to do this, and most faults are only detectable whilst the aircraft is in flight. Temperature, humidity and vibration all accelerate ageing and failure effects on EWIS. This research investigates methods of in-situ non-invasive testing of aircraft wiring during fight. Failure Mode Effects and Analysis (FMEA) was performed on legacy aircraft EWIS using data obtained from RAF Brize Norton. Micro-Electro-mechanical- Systems (MEMS) were evaluated for use in a wire monitoring system that measures the environmental parameters responsible for ageing and failure of EWIS. Such MEMS can be developed into a Health and Usage Monitoring MicroSystem (HUMMS) by incorporating advanced signal processing and prognostic software. Current and humidity sensors were chosen for further investigation in this thesis. These sensors can be positioned inside and outside cable connectors of EWIS so that arc faults can be reliably detected and located. This thesis presents the design, manufacture and test of micro-manufactured Rogowski sensors. The manufactured sensors were benchmarked against commercial high frequency current transformers (HFCT), as these devices can also detect high frequency current signature due to wire insulation failure. Results indicate that these sensors possess superior voltage output compared to the HFCT. The design, manufacture and test of a polymer capacitive humidity sensor is also presented. Two different types of polymer were reviewed as part of the evaluation. A feature of the sensor design is recovery from exposure to chemicals found on wiring bundles. Current and humidity sensors were demonstrated to be suitable for integrating onto a common substrate with accelerometers, temperature sensors and pressure sensors for health monitoring and prognostics of aircraft EWIS.Engineering and Physical Sciences Research Council (EPSRC

Micro-manufactured Rogowski coils for fault detection of aircraft electrical wiring and interconnect systems (EWIS)

Aircraft wiring failures have increased over the last few years resulting in arc faults and high-energy flashover on the wiring bundle, which can propagate down through aircraft Electrical Wiring and Interconnect Systems (EWIS). It is considered cost prohibitive to completely rewire a plane in terms of man hours and operational time lost to do this, and most faults are only detectable whilst the aircraft is in flight. Temperature, humidity and vibration all accelerate ageing and failure effects on EWIS. This research investigates methods of in-situ non-invasive testing of aircraft wiring during fight. Failure Mode Effects and Analysis (FMEA) was performed on legacy aircraft EWIS using data obtained from RAF Brize Norton. Micro-Electro-mechanical- Systems (MEMS) were evaluated for use in a wire monitoring system that measures the environmental parameters responsible for ageing and failure of EWIS. Such MEMS can be developed into a Health and Usage Monitoring MicroSystem (HUMMS) by incorporating advanced signal processing and prognostic software. Current and humidity sensors were chosen for further investigation in this thesis. These sensors can be positioned inside and outside cable connectors of EWIS so that arc faults can be reliably detected and located. This thesis presents the design, manufacture and test of micro-manufactured Rogowski sensors. The manufactured sensors were benchmarked against commercial high frequency current transformers (HFCT), as these devices can also detect high frequency current signature due to wire insulation failure. Results indicate that these sensors possess superior voltage output compared to the HFCT. The design, manufacture and test of a polymer capacitive humidity sensor is also presented. Two different types of polymer were reviewed as part of the evaluation. A feature of the sensor design is recovery from exposure to chemicals found on wiring bundles. Current and humidity sensors were demonstrated to be suitable for integrating onto a common substrate with accelerometers, temperature sensors and pressure sensors for health monitoring and prognostics of aircraft EWIS