Research On Single Phase High Voltage And Large Capacity Electrical Router Based On 81 Level

Power scheduling is an important part to ensure the normal operation of electrified railway.On the one hand,the electric locomotive belongs to high power nonlinear load,it can reduce traction network voltage and power factor and has great influence on surrounding power.On the other hand,considering that the locomotive has obvious peaks and valleys in the operation period,and unbalanced energy supply in traction network,the premise of saving energy and reducing operating costs,it is of great significance to come up with an energy routing device that can make the electrified railway power supply system run in line with locomotives in traction network.According to the characteristics of power supply system of electrified railway,such as single-phase,high voltage,large capacity and obvious peak-valley period,a new type of router device was proposed.The device adopted the voltage amplitude-phase angle energy scheduling method to ensure the normal power supply of electric locomotives and the voltage support of the traction network,through the 81 level transformation technology meet the electrified railway power system on the quality of the grid converter high power and high voltage requirements,the final energy storage unit based on virtual dc motor control to achieve power consumption and stability control.For the energy scheduling scheme,a voltage amplitude-phase angle control strategy was adopted.Based on the power requirements of the electrified railway,the voltage amplitude and phase that the power router's output power was derived.By analyzing the effects of voltage amplitude and phase on the dispatching active power,reactive power,and the types and characteristics of distributed energy,The optimal control model achieved power scheduling and peak load cutting was established.For the 81-level converter,a multi-level step wave modulation was used.Based on the relation between the base-wave voltage of the converter and the capacitor voltage of the dc bus,the sinusoidal step-wave output was realized by controlling the capacitance voltage and calculating the on-off time of each group by segmenting the sine wave.At the same time,the complexity of the multilevel modulation method and the h-bridge power distribution are compared with the existing technology,and the advantages of the technology in the high-voltage power field such as electrified railway was analyzed.Aimed at the consumption of renewable energy and ensuring the stability of the system,a two-way energy storage converter based on virtual DC motor control was used.Based on the principle analysis,a control scheme for the energy storage unit was established,and the feasibility of the scheme was theoretically verified using small signal analysis and parameter optimization,meanwhile,under the condition of unstable power generation,by observing the DC bus voltage fluctuations,The influence of the scheme on the damping and inertia of the system was analyzed.Finally,MATLAB was used to build a simulation model of the power router,which simulated the working conditions of the electric locomotive when it enters/exits the station,and verified that the scheme is not only effective in power scheduling and peak cutting and valley filling,but also can improve the stability of the power supply system composed of the power router and traction network.