No commutation zone and in-phase traction power supply system for electrified railway

Abstract

The invention discloses a device for converting balanced three-phase electric power into single-phase electric power, which comprises a plurality of electrified railway traction power supply devices which are composed of an electronic device and / or a motor transformer. The devices have the advantages of high efficiency, energy saving, low cost, easiness in manufacturing and so on, the capacity of power processed by the electronic device accounts for about 46% to 67%, the balanced three-phase electric power can be converted into the single-phase electric power, and better three-phase balance and high power factor can be obtained by negative sequence compensation and reactive power compensation, therefore, the commutation zone in the electrified railway can be canceled, so as to save the investment in railway construction, stabilize the train power supply, and improve the safety of train operation.

Description

[0001] field of invention [0002] The invention belongs to the electric energy transmission technology in the field of electric technology, and in particular relates to three-phase balanced traction power supply of electrified railways. Background technique [0003] Electrified railway is an important means of railway traction energy supply. Electrified railways are mainly powered by the AC power grid, but the current power grid is a three-phase system, which requires the three-phase currents to be equal, otherwise negative-sequence currents and reverse-sequence magnetic fields will be generated, which will affect the normal operation of generators and motors in the power grid. However, it is difficult for the traction network and pantograph to introduce three-phase power into the train, and only a single-phase traction network can be used to transmit electric energy to the train. Moreover, the power consumption of the train is huge, and it is easy to generate unbalanced thre...

AI Technical Summary

Problems solved by technology

Therefore, excessive phase separation is still a technical bottleneck for traction power supply of electrified railways

[0006] 2. High-speed and heavy-duty transportation require large-capacity power supply. In order to meet the national standard power system restrictions on electrified railway power quality with negative sequence as the most prominent indicator, the reactive power compensation technology used in the original out-of-phase power supply method has been unable to adapt

If the adjustable symmetrical compensation is adopted in the traction substation, it will be difficult to achieve the ideal state both technically and economically

[0007] 3. The high-speed railway to be built in my country may be a mixed operation mode of high and medium speeds. If there is a mixed use of AC-DC locomotives and AC-DC locomotives, in addition to negative sequence, reactive power and harmonics still exist, and power quality cannot be improved. Electrified railways Will face the problem of high electricity bills

At the same time, the loss of speed and traction may further widen the speed difference between high-speed and medium-speed trains, affecting the overall transportation capacity

[0008] 4. In addition, during the construction of the electrified railway, the construction of the phase separation area must be increased at the same time, which increases the construction cost; at the same time, when the train passes through the phase separation area, the power supply of the train is blocked, and it may be in a state of power failure, which may also bring equipment Fault

Images