High-voltage DC transmission converter valve single-row valve tower

Abstract

The invention provides a high-voltage DC transmission converter valve single-row valve tower which comprises a top shielding cover, a bottom shielding cover and a converter valve arranged between the top shielding cover and the bottom shielding cover, wherein the top shielding cover and the bottom shielding cover are arranged horizontally. The converter valve is connected with the top shielding cover and the bottom shielding cover through suspension insulators. The converter valve is formed by connecting converter valve modules, forming an inclination angle with the horizontal direction, in series in sequence in the vertical direction in the form of a zigzag rule. The high-voltage DC transmission converter valve single-row valve tower is more compact in overall structure and more reasonable in layout, and meanwhile, better solves the problems of high-frequency oscillation due to cooling water circuit insulation and connecting busbar inductance, reduces operational risks, and meets the design requirement for higher voltage and current level of the (ultra) high-voltage DC transmission converter valve.

Description

technical field [0001] The invention relates to a valve tower, in particular to a foldable single-row valve tower for a high-voltage direct current transmission converter valve. Background technique [0002] The increasing demand for electric energy in modern social and economic activities has promoted the continuous evolution of the structure and scale of the power system. At present, in order to adapt to the characteristics of high concentration of power load and energy distribution and the shortage of energy resources in heavy load areas, and to meet the requirements of environmental protection, large-scale clean energy centralized development and long-distance transmission have gradually become the mainstream energy development and utilization methods. DC transmission technology is widely adopted due to its economic advantages in long-distance transmission of electric energy and technical advantages in enhancing grid stability. [0003] The HVDC converter valve is the c...

AI Technical Summary

Problems solved by technology

First, the increase in voltage requires an increase in the withstand voltage capacity of the converter valve, an increase in the number of series series of converter valve components, an increase in the size of the converter valve module and the insulation distance between layers of the valve tower, and objectively requires the conversion The appearance size of the valve tends to increase accordingly, but the cost of occupying space for the converter valve hall is becoming more and more expensive. Hall area ratio

Second, the main water pipe between the layers of the converter valve is connected between the two-layer modules of the valve tower, and its two ends must bear the inter-layer voltage of the converter valve. The increase in voltage will increase the leakage current in the inter-layer water pipe, affecting the layer The static distribution of the voltage between the valves and the electrical corrosion of the metal joints in the water pipes will reduce the working reliability and life safety of the valve tower

Third, the capacitive shunting effect of the converter valve shielding system leads to uneven voltage distribution between the converter valve layers, and the increase in the size of the valve tower and the number of series series will aggravate this unevenness

However, because the interlayer busbars in the valve tower of the converter valve have a certain inductance, under the action of high-frequency impulse voltages such as lightning waves, high-frequency oscillations will occur between this part of the inductance and the voltage equalizing capacitor of the components. Cause high-frequency oscillating voltage across the thyristor element in the converter valve, such as Figure 3

Oscillating voltage peak value and high voltage change rate are very unfavorable to thyristors. In severe cases, batches of thyristors can be damaged and cause the shutdown of the converter station

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