There were four great inventions in ancient ChinaGunpowder, papermaking, printing, compass, and now China has already had the new four major inventions-High-speed rail, QR code payment, bike sharing, and online shopping.
In fact, for high-speed rail, we have to talk about the southern blizzard in 2008On January 26, 2008, during the Spring Festival, people were carrying large bags and small bags to go home for the New Year.
However, continuous snowfall caused the railway line to be blocked, forcing 136 trains to be delayed and suspendedAs a result, a large number of tourists were stranded at the railway station, and the number of people stranded at the Guangzhou railway station exceeded 100,000 on the same day.
After that incident, it also completely "angered" my countryIn 2003, China's first high-speed national railway line was completed, but by 2008, China's high-speed railway operating mileage was only 1,035 kilometers.
After 2008, my country began to win a number of titles:The world's fastest operating high-speed rail station, the world's longest high-speed rail bridge, the world's first commercial maglev high-speed railway, and so on.
In 2009, the operating mileage of high-speed railways increased by 2,249 kilometers, in 2010 there were 3,559 new additions, in 2014 there were 4,746 new additions, and in 2016 there were 2,104 kilometers of new additions.
By the end of 2023, China's railway operating mileage will reach 1590,000 km,And the high-speed rail up to 450,000 kilometers, has already become the world's first.
But have you ever thought that high-speed rail, a fast and convenient means of transportation, can run at high speed at the same timeWhile bringing such convenience to our country's economic development and people's daily travel, where is the 9,600 kWh of electricity consumed every day charged?
Don't look at the speed of high-speed rail, but the energy consumption of high-speed rail is closely related to its speedFor example, a high-speed train with a speed of 350 kilometers per hour consumes 9,600 kilowatt-hours of electricity per hour, while a high-speed train with a speed of 250 kilometers per hour consumes only 4,800 kilowatt-hours of electricity per hour.
The increased speed leads to an increase in traction power, resulting in a significant difference in energy consumptionHigh-speed rail consumes a lot of electricity during operation, and operating costs and maintenance expenses increase significantly.
High-speed rail operation requires a lot of electrical energy, which increases energy costsThe construction process also requires a lot of energy resources, so where does the electricity for the high-speed rail come from?
In fact, the electric energy of high-speed rail is different from that of the national gridThe high-speed rail system has a traction substation, and on the road, a substation will be configured at certain distances.
These substations draw electricity from the national grid and supply the high-speed rail EMUs through a catenary directly above the high-speed rail line.
Due to the large traction load current of high-speed rail, it fluctuates violently, and it is a single-phase loadTherefore, the external power supply voltage requirements are high, and a higher voltage level is often chosen, such as 220 kV.
When it comes to the catenary, it drops to 25 kVThis voltage shift is to adapt to the needs of high-speed rail and ensure the stable delivery of current.
The catenary is a key part of the high-speed railway's access to electric energy, and the high-speed train is in sliding contact with the catenary through the pantographThe power transmitted from the traction substation is obtained to power the train.
This "Z" shaped contact method helps to reduce wear and extend the service life of the catenaryAt the same time, it can also ensure the stable transmission of current.
After the current passes through the catenary, it also needs to pass through the power grid and current conversion equipment inside the motor car, which is responsible for providing 27 of the catenary5kV high-voltage alternating current is converted into low-voltage direct current used inside the EMUIt is essential to ensure the safety of passengers.
The light control system of the EMU also reflects the complexity of electricityThere are multiple lighting control modes inside the train, which can be adjusted according to the external environment and driving conditions.
For example, the interior lights automatically adjust their brightness based on the intensity of the dayto ensure the comfort of passengers; In the event of an emergency, the emergency lighting system is automatically activated to ensure the safety of passengers.
When it comes to the choice of power supply, AC has many advantages, such as the ease of changing voltage and frequencyIt is convenient for long-distance transmission and can reduce energy loss, and the high-speed rail system uses alternating current as the main power supply method.
The location design of the traction substation is also very particular. The traction substation is usually set up at the appropriate location of the high-speed rail line to ensure the continuity and stability of the power **.
The high-speed rail is not a continuous power supply throughout the whole process, and it is in the non-electric section between the substationsThe train retracts the pantograph and glides at high speed under its own inertia.
The process is almost imperceptible to passengersMoreover, the batteries equipped with high-speed rail trains can provide emergency backup power in the event of a power outage, ensuring that the train can still operate and maintain safety in the event of a power outage.
If the battery is depleted, the high-speed rail command system will send a distress signal to the traction substations along the way, so that the head of the internal combustion engine-powered locomotive can tow the high-speed rail EMU to its destination.
When taking the high-speed rail, pay attention to not wearing an umbrella on the high-speed rail station when it rainsThe first is that it is close to the power grid, which is easy to cause electric shock, and the second is that the wind is strong in a moment brought by the high-speed rail, which is very easy to blow the umbrella away, causing unnecessary trouble.