[phone] as you can see, when transmitting the same power, one time at 177. 660 kv and 177. 500 kv, 177. Based on the transects of the lines actually selected for high-voltage/high-voltage direct-flow transmission and very-high-voltage transmission, it is easy to see that the power and energy loss rates for communication are less than those for direct-flow transmission. 5. The construction costs of high-voltage/high-voltage direct-flow transmission systems are compared to the construction costs of high-volume, long-range direct-flow transmission systems, characterized by the complex structure of the switch station, its large area and the high cost of construction, and the smaller cost and environmental impact associated with the selection of smaller line sections. For example, 177. With increased transmission distance and voltage, the share of line construction costs will increase the cost of large-capacity long-range communication transmission systems, characterized by the simple structure of two-end transformers and switches, the small size of the ground and the relatively large proportion of construction costs for empty transmission routes. %. As price indices vary from year to year, direct/exchange power transmission construction cost comparisons should convert the cost of transmission construction work that is in operation in different years to the same year. The cost and power loss for the construction of high-voltage/high-voltage direct-flow transmissions and ultra-high-voltage communications are calculated and compared against direct-flow transmissions as shown in table 8. 500000989 1000 3000989 177. The construction costs and power losses in table 800772001600 100042901600 are based on direct current transmission at the various voltage levels. 800kv direct transmission capacity. Theoretically and empirically, it has been shown that with the current direct transmission principles and technologies available, it is not possible for the direct transmission system to be able to achieve both lower costs for the construction of the transmission lines, as well as lower power and volume losses. For example, 177. As a result of the increase in the total cross-section of the empty lines, 177. 177. 177. 177. 800kv line transects with a weight greater than 1,000 kv, ~ 6. Comparison of the operating costs of high-pressure/high-pressure direct-flow transmission to the high-pressure communication year construction costs are considered at an average cost recovery rate of 10 years. A comparison of 500 kv with the annual running cost of 1,000 kv transmission systems, the construction cost of 1,000 kv high-voltage transmissions is 177, as can be seen from the calculation of the construction cost and the cost of the loss of power. Comparative results are: 3,000 mw, 989 km, 177.%. The annual running cost of the 800kv compared to 1,000 kv transmission systems was 177. The cost of construction of the transmission system is referred to in paragraph 3. 177. Calculated if 177. 1000 kv, 4290 mw, 8x630 converted to comparable capacity, 177. 800kv, 6x1000. The cost of running the 800kv straight stream relative to the 1000kv transmission system is shown in table 9. 800kv direct current compared to the operating cost of 1000 kv tx (kv) rated voltage (kv) transmission power (mw) split-conductor transect (mm2) unit transmission power construction cost ratio (mm2) per unit transmission power power generation loss compared to the annual operating cost per unit transmission power of 177. The calculation analysis showed that: the construction cost of 1,000 kv, 1600 km, is 177 for power transmission units. The direct flow of electricity from 800 kv is much lower, and the annual running cost of 1,000 kv units is less than 177. The calculation shows that the annual running cost of a 1,000 kv high-voltage exchange is less than the direct stream. Since the introduction of minimum life-cycle cost decisions for power transmission projects, significant and sustained economic benefits have been generated to reduce power loss and improve reliability of transmission systems
9]. The common formula for life-cycle costs is: lcc=ic+oc+mc+fc(8) for construction costs, oc, mc, and fc, respectively, the sum of annual operating costs over the life-cycle, the sum of the cost of loss of electricity, and the sum of the cost of loss of unreliable. Thus, life-cycle costs based on the time of conversion can be written as follows. When comparing the cost of high voltage/high voltage direct current transmission with the cost of 1000 kv exchange transmission, it is assumed that the cost of operating, managing and loss of reliability of the high voltage/high voltage direct stream transmission and 1000 kv exchange transmission is the same (in practice, the cost of operating direct stream maintenance and loss of reliability is higher than the cost of communication transmission). Thus, only construction costs and electricity loss costs are considered when comparing life-cycle costs. Table 10 cost of direct-flow transmission versus exchange transmission life-cycle cost of rated (kv) transmission power (mw) transmission distance (km) construction cost (symmetric value) plcc (symmetric value) 177. 6604000135041004000350177. Conversion of 1,000 kv to 177. As can be seen from table 10, with the same distance and transmission power, the construction cost of 1,000 kv communications increased by approximately 11 per cent compared to the high voltage/extremely high-voltage direct stream, but the cost of loss of electricity decreased by 74 per cent, 47 per cent and 29 per cent, respectively. The life-cycle cost of 1,000 kv exchange transmissions is 177 at the same distance and the same transmission power. 660 kv, 177. The replacement of direct current transmission with 1,000 kv will significantly reduce life-cycle costs, significantly reduce the cost of loss of electricity transmission and have significant and sustained economic and social benefits for energy efficiency and reduction. The cost of reducing transmission capacity over a 30-year period compared to the direct transmission system of 800kv, 6x720 mm2, could result in the construction of a 1000 kv, 8x630 mm2 1600 km transmission system. The amount of electricity delivered by the 800kv, 6x720 mm2 direct-flow transmission system in one year could save 10. 22 million tons of coal and reduce co2 emissions by 26. 6 million tons. The literature [4] predicts that by 2020, five 177 projects will have been built abroad. 800 kv open-line direct power transmission works, of which 2 are in brazil, 2 in africa and 1 in india. If 40 high-pressure/high-pressure direct-flow transmissions are implemented, in 2020, we will have a high-pressure/% of our empty line. Based on the power and distance of the different levels of direct current voltage, it is assumed that the 220 gw225gw direct-flow transmission project will be implemented and that by 2020 the total direct-flow transmission power loss is expected to be 1,665 mw or more, equivalent to the lost installed capacity of 16650 mw or more. %, %. % rose to 11% and above. Three-way transmission is an economic, reliable and flexible mode of transmission that adapts to changes in the power supply and the load used, and direct-flow transmission and any other method of transmission is not comparable. High-voltage/extremely-high-voltage direct-flow transmission cannot be achieved at the same time with low line construction costs, low power and power loss rates and low operating costs for transmission; high-voltage/extreme-high-voltage direct-flow line large-capacity long-range transmission of electricity in comparison to ultra-high-voltage three-stage transmissions, high operating costs and low operational reliability; 177 in construction and delivery. The construction of direct-flow power transmission projects will continue in large numbers, the rate of electricity loss to the grid will continue to rise, the reduction of energy efficiency to the grid will face serious challenges and the actual utilization of electricity generation in the country will be significantly reduced, contrary to our energy conservation, development and conservation policies. The least cost-effective technology option for life-cycle planning and construction of future power transmission projects is desirable. 800kv direct-flow transmission is much lower. Study of an economically efficient and secure structure of 1,000 kv transmission grids, integration of existing direct transmission systems into 1,000 kv grids and construction of a super-wide grid of “strength and weakness”. Iet seminar on power system security and stability, 2007 wg3804amp. 600kv and above, part 1 and part 2, 1988 cigre summit, report 3812, 1988, hvdc coNever status for voltages above 177. If we do or don't do it, and if we don't do it and do it well, we'll do it better and laugh! Do not be a slave of money, power; learn to be the master of money, power. The most commendable scenery is the footprint of your own struggle. It's not that someone works harder than you, it's that person who's many times more than you
