Electric railway electric energy quality comprehensive treatment device control method

Abstract

The invention discloses an electric railway electric energy quality comprehensive treatment device control method. A single-phase multi-winding transformer secondary side is provided with a railway power regulator and a thyristor control filter. The railway power regulator is provided with more than two converters sharing a DC (direct current) side capacitor to form a back-to-back structure and connected with each other in parallel; and the AC (alternating current) output ends of the converters are connected to the M-phase and T-phase power supply seats through a connection electric reactor and a transformer. A winding of each transformer secondary side is respectively provided with more than two groups of thyristor control filters connected with each other in parallel; and each thyristor control filter is provided with more than two groups of filter branches connected with each other in parallel. The railway power regulator balances the active power between the M-phase and T-phase power supply seats. The thyristor control filter compensates for the reactive power of the M-phase or T-phase power supply arm and filters the harmonic wave. The method disclosed by the invention can realize comprehensive treatment of the negative sequence, harmonic wave and reactive power of the electric railway, and can properly reduce the active capacity so as to achieve the aims of improving the treatment effect and reducing the cost.

Description

technical field [0001] The invention relates to a control method of a power quality control device, in particular to a control method of an electrified railway power quality comprehensive control device based on SCOTT (Scott) transformer power supply applied to an electrified railway traction power supply system. Background technique [0002] In recent years, my country's electrified railway has developed very rapidly, and has the advantages of strong carrying capacity, fast driving speed, high energy saving, and low environmental pollution, which has played a pivotal role in the rapid development of the national economy. However, due to the high-power single-phase load of electric locomotives, which have the characteristics of nonlinearity, asymmetry and volatility, a large number of negative sequence, reactive power and harmonic currents are injected into the grid during operation, which causes grid voltage fluctuations to be distorted, three-dimensional Phase unbalance, l...

AI Technical Summary

Problems solved by technology

The Scott (SCOTT) transformer included in this system is only used as an isolation transformer to connect the three-phase converter to the two-phase circuit formed by the traction substation. It can be regarded as an unbalanced three-phase load, which will cause the fundamental wave distortion of the inverter output voltage; it is difficult for the three-phase inverter to realize the transfer of active power from one phase to another

However, it treats the two power supply arms of the traction substation separately, ignoring the mutual influence between the two power supply arms. If active equipment with fast dynamic response is used, the system may be unstable and it is difficult for the two arms to reach load balance status

Images