Compensation transformer

Abstract

The invention discloses a compensation transformer which relates to the technical field of traction power supply for AC electrified railway. The transformer comprises an iron core, a first primary winding and a first secondary winding wound on a single-phase iron core, a second primary winding and a second secondary winding wound on another single-phase iron core; An X terminal of the second primary winding is connected with a neutral point of the first primary winding; An x terminal of the second side winding is connected with a neutral point of the first side winding; The T terminal of the second primary winding and the t terminal of the second secondary winding are identical polarity terminals, and the R terminal of the first primary winding and the r terminal of the first secondary winding are identical polarity terminals; The r terminal, the s terminal and the t terminal are used for connecting the reactive power compensation device; Combined with single-phase traction transformer, it can not only realize in-phase power supply, cancel phase separation, effectively eliminate the voltage unbalance problem of three-phase system caused by single-phase load, but also occupy less space, easy to install and implement, at the same time, it can enhance the energy-saving and cost-saving effect of traction power supply system.

Description

technical field [0001] The invention relates to the field of AC electrified railway power supply, in particular to a compensation transformer with good negative sequence compensation function, which is used in conjunction with a single-phase traction transformer. Background technique [0002] Electrified railways generally adopt the single-phase power frequency AC system powered by the public power system. In order to make the single-phase traction load be distributed as balanced as possible in the three-phase power system, the electrified railway often adopts the scheme of rotating phase sequence and separate phase and partition power supply. The adjacent power supply areas at the phase-splitting partitions are divided by phase-splitting insulators to form electrical split phases, also known as phase splits. In order to prevent electric locomotives from burning out catenary suspension components due to arcing through electric split-phase emission, and even causing phase-to-...

AI Technical Summary

Problems solved by technology

[0003] High-speed and heavy-duty railways have widely used high-power AC-DC electric locomotives or EMUs based on full-control devices such as IGBTs and IGCTs. The core is traction converters with multiple sets of four-quadrant PWM control and multiple control. The content is small, and the power factor is close to 1, but the traction power of AC-DC electric locomotives or EMUs is large. For example, the rated power of high-speed EMUs operating in large formations is 25MW, which is equivalent to 5 times that of ordinary-speed railway trains. The main problem of power quality caused by power single-phase load to three-phase grid will be the problem of three-phase voltage unbalance (negative sequence)

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