Electromagnetic mixed compensation system for quality of electric energy in electrified railways

Abstract

The invention provides an electromagnetic mixed compensation system for quality of electric energy in electrified railways. The electromagnetic mixed compensation system comprises an RPC, two MSVCs and a V / V traction transformer. The V / V traction transformer is in a V / V type formed by connecting two single-phase transformers. The primary side of the V / V traction transformer is connected to a three-phase public power grid, and traction power supply arms serve as two output ends of the secondary side of the V / V traction transformer. Each MSVC comprises a magnetic controlled reactor, a third single harmonic filter branch circuit and a fifth single harmonic filter branch circuit, and the magnetic controlled reactor, the third single harmonic filter branch circuit and the fifth single harmonic filter branch circuit are connected in parallel. The RPC comprises two H-bridge converters with a shared direct-current side. The MSVCs and the RPC are used in cooperation with each other, and therefore the problem of unbalanced harmonic and negative sequences of the electrified railways is solved. Due to the adoption of MSVC and RPC mixed compensation, compensation capacity of the RPC is effectively reduced, and the construction cost of the system is accordingly reduced.

Description

technical field [0001] The invention belongs to the field of electric power quality compensation for electrified railways, in particular to an electromagnetic hybrid compensation system for electric power quality of electrified railways. Background technique [0002] Nearly 8,000 kilometers of high-speed railways have been successfully put into operation in China, making my country the country with the fastest and longest high-speed railways in the world. The high-speed railway load adopts the AC-DC-AC power supply strategy based on pulse width modulation. Compared with the conventional electrified railway locomotive traction load, it has the characteristics of large instantaneous power, high power factor and a large number of high-order harmonics. As a single-phase high-power load, the high-speed rail load will generate a large amount of negative sequence current. These negative sequence currents will not only cause motor vibration and additional losses, but also cause rela...

AI Technical Summary

Problems solved by technology

However, the compensation capacity required for RPC compensation is large, and the cost per unit capacity of power electronic devices is high, so the cost is very high, which limits the development of RPC compensation methods.

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