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A method to determine the minimum horizontal separation distance between transmission lines and underground pipelines for inductive electromagnetic interference mitigation under normal operation of transmission lines is proposed in this paper. The proposed method takes both AC corrosion of pipelines and a 15 V touch voltage safety limit into account. For a pipeline facility of Manitoba Hydro, soil resistivity is firstly measured at 20 locations near the pipeline; a soil model is then created for each location using the RESAP module in CDEGS software package. Two critical soil resistivity values for AC corrosion limit and 15 V voltage limit are selected for this pipeline facility. After the soil model is determined, the HIFREQ module in CDEGS is used to simulate the induced AC voltage, and a minimum separation distance can be recommended. Four voltage classes of transmission lines, 115 kV, 138 kV, 230 kV, and 500 kV, are considered. Two curves and their empirical models are created for each voltage class to determine the minimum separation distance. The modeling method is validated using two case studies with field measurements. The proposed method and guidelines can significantly improve the future line route selection process for new transmission lines. [ABSTRACT FROM AUTHOR]

This paper describes the application of a controlled switching device to energize a 500 kV/230 kV/46 kV, 1200 MVA autotransformer in Manitoba. The development of a detailed electromagnetic-transient (EMT) simulation model of the transformer formed the basis of the work described. The transformer model includes an accurate representation of hysteresis and remanance, which was validated using recorded waveforms and manufacturer data. This paper discusses a feasibility study conducted using this transformer model to evaluate the suitability of controlled switching to energize this transformer. A series of real-time hardware in the loop tests was conducted using a real-time simulator as part of precommissioning tests. The real-time simulation (RTS) tests and phase 1 of commissioning tests conducted in October 2014 showed that the controlled switching device would produce inaccurate residual flux estimates when it integrates the secondary voltage waveforms of a capacitive voltage transformer. Based on these RTS test results and EMT simulations, the installation of a wound potential transformer (PT) was recommended. This paper also discusses simulation studies conducted to manually program the controller until the PT was commissioned. During phase 2 of testing conducted in October 2015, a wound PT was commissioned and the controller was tested. The recorded waveforms showed good agreement with simulation results. The controller has accurately predicted residual flux and minimized inrush currents during transformer switching events. [ABSTRACT FROM PUBLISHER]

The paper presents a new transformerless single-phase single-stage buck–boost grid-connected voltage source inverter (VSI) topology. The topology can achieve efficient power conversion with a wide input voltage range, number of magnetic devices reduction and low leakage current. The proposed VSI topology consists of high frequency semiconductors for shaping inductor currents, and low frequency semiconductors to form grid CL filter structure for different conditions. This CL filter uses the same buck–boost inductor, thus no additional line frequency inductor is required. Besides, common mode voltage, a main problem of transformerless grid-connected VSI, is mitigated, since the capacitor in the CL filter clamps the voltage between the grid and the bus terminal. The performance of the proposed VSI is experimentally verified. The results show that the proposed VSI guarantees sinusoidal output current and wide input voltage range, and has a good agreement with the theoretical findings. [ABSTRACT FROM AUTHOR]

IEEE Std. 516-2009 and IEC 61472-2013 present Minimum Approach Distance (MAD) requirements for tools to perform live maintenance safely, provided that the tool has no continuous film of moisture or measurable contamination present on its surface. However, four separate "clean" FRP hot-stick flashover incidents occurred in Canada under steady-state system conditions at the peak of the voltage negative half-cycle during cold and freezing conditions. This paper investigates IEC and IEEE methods of calculating MAD for tools employed for live working done on the geometry of the Manitoba site incidents at 500-kV. Based on cold fog tests carried out at CIGELE to reproduce these incidents, guidelines for calculating MAD in cold and freezing climate regions are proposed. [ABSTRACT FROM AUTHOR]

The performance of multiple-input multiple-output (MIMO) systems using beam selection is investigated in this paper. Based on the results of a channel sounding campaign carried out at the University of Manitoba for line-of-sight (LOS) and non-line-of-sight (NLOS) scenarios, it was possible to contrast the results of transmitter, receiver and joint beam selection in rich scattering environments. The channel was characterized in the 1-2.4 GHz frequency band with a multipath delay resolution better than 5.8 ns. The beam selection was performed by exhaustive search method. The results led us to important conclusions regarding the beam selection procedure and its potential to improve the indoor channel capacity. In LOS, the single input single output (SISO) system that favours the maximum power direction of arrival (DOA) maximizes the capacity. Capacity improvements are observed by increasing the number of receiver beams (RBs) only at high signal-to-noise ratios (SNRs) for omnidirectional transmission. The best performance in transmitter beam selection in LOS is observed by increasing the number of transmitter beams (TBs) for high SNRs. In the case of NLOS, the capacity performance is improved when more than a single beam is used in either, transmitter or receiver side. The joint transmitter-receiver beam selection exhibits best capacity performance only for large SNRs in LOS while the SISO systems outperforms any joint beam selection alternative for low SNRs. In contrast, in NLOS environments, the use of joint beam selection shows a constant capacity performance improvement starting from lower SNR than in the LOS case. [ABSTRACT FROM AUTHOR]