To avoid stray current and maintain the benefit of no phase-split in the DC traction power supply system, an AC traction power supply system was proposed for the urban public transport such as metro and light rail tra...To avoid stray current and maintain the benefit of no phase-split in the DC traction power supply system, an AC traction power supply system was proposed for the urban public transport such as metro and light rail transit. The proposed system consists of a main substation （MSS） and cable traction network （CTN）. The MSS includes a single-phase main traction transformer and a negative-se- quence compensation device, while the CTN includes double-core cables, traction transformers, overhead catenary system, rails, etc. Several key techniques for the proposed system were put forward and discussed, which can be summarized as （1） the power supply principle, equivalent circuit and transmission ability of the CTN, the cable-catenary matching technique, and the selection of catenary voltage level; （2） the segmentation technology and status identification method for traction power supply network, distributed and centralized protection schemes, etc.; （3） a power supply scheme for single-line MSS and a power supply scheme of MSS shared by two or more lines. The proposed industrial frequency single-phase AC traction power supply system shows an excellent technical performance, good economy, and high reliability, hence provides a new alternative for metro and urban rail transit power supply systems.展开更多
In this paper, a wireless power transmission system using magnetic resonance coupling was proposed and demonstrated for supplying power at high efficiency to electrical devices in a space enclosed by metal walls. This...In this paper, a wireless power transmission system using magnetic resonance coupling was proposed and demonstrated for supplying power at high efficiency to electrical devices in a space enclosed by metal walls. This is applicable to power supply to electrical sensors or devices working in the area surrounded by metal walls. Proposed magnetic resonance coupling system is driven at a resonance frequency of 50 Hz, which is selected to avoid eddy current loss on the surrounding metals. Firstly, resonator designs and its performance limitation were described. Secondly, the equivalent circuits and theoretical transmission efficiency were presented. Finally, power transmission was experimentally demonstrated and transmission efficiency was measured in some conceivable situations. As a result, electric power of 3 W was supplied to LEDs over a stainless steel wall. When the stainless steel wall thickness was 10 mm, transmission efficiency of approximately 40% was achieved over the transmission distance of 12 cm. Moreover, in the demonstration of transmission through a metal pipe, 1.2 W of power was transmitted to LEDs in a 10 mm thick metal pipe.展开更多
文摘To avoid stray current and maintain the benefit of no phase-split in the DC traction power supply system, an AC traction power supply system was proposed for the urban public transport such as metro and light rail transit. The proposed system consists of a main substation （MSS） and cable traction network （CTN）. The MSS includes a single-phase main traction transformer and a negative-se- quence compensation device, while the CTN includes double-core cables, traction transformers, overhead catenary system, rails, etc. Several key techniques for the proposed system were put forward and discussed, which can be summarized as （1） the power supply principle, equivalent circuit and transmission ability of the CTN, the cable-catenary matching technique, and the selection of catenary voltage level; （2） the segmentation technology and status identification method for traction power supply network, distributed and centralized protection schemes, etc.; （3） a power supply scheme for single-line MSS and a power supply scheme of MSS shared by two or more lines. The proposed industrial frequency single-phase AC traction power supply system shows an excellent technical performance, good economy, and high reliability, hence provides a new alternative for metro and urban rail transit power supply systems.
文摘In this paper, a wireless power transmission system using magnetic resonance coupling was proposed and demonstrated for supplying power at high efficiency to electrical devices in a space enclosed by metal walls. This is applicable to power supply to electrical sensors or devices working in the area surrounded by metal walls. Proposed magnetic resonance coupling system is driven at a resonance frequency of 50 Hz, which is selected to avoid eddy current loss on the surrounding metals. Firstly, resonator designs and its performance limitation were described. Secondly, the equivalent circuits and theoretical transmission efficiency were presented. Finally, power transmission was experimentally demonstrated and transmission efficiency was measured in some conceivable situations. As a result, electric power of 3 W was supplied to LEDs over a stainless steel wall. When the stainless steel wall thickness was 10 mm, transmission efficiency of approximately 40% was achieved over the transmission distance of 12 cm. Moreover, in the demonstration of transmission through a metal pipe, 1.2 W of power was transmitted to LEDs in a 10 mm thick metal pipe.
