How does the most thermal power network generate a

  • Detail

How does electricity generate as much electricity as it uses

when talking about the storage of electricity, many people have a question:

can electric energy be stored in large quantities like water? Save it when there is much electricity, and put it out when there is a lack of electricity

the natural answer is: No

since electricity cannot be stored in large quantities, what about extra electricity? Waste it

in fact, it will not be wasted, because there is basically no situation that the electricity generated cannot be used up. Generate and use as much as you need, and generate electricity on demand

so advanced? What about the energy storage power station? Today, let's talk about how to achieve the dynamic balance of supply and demand and electric energy storage

01 more often, even if you have to pay for repair, electricity will not be stored

it is a world consensus that electricity cannot be stored in large quantities. Whether it is batteries or pumped storage power stations, the proportion of stored electricity in the total electricity consumption of the whole society is very small

since it doesn't seem very reliable to use energy storage to realize power supply, it can only be used immediately. How can it be achieved

this involves the electric dispatching control system

most of the power generation, transmission, distribution and consumption of CEC operate in the form of alternating current. Even if UHV DC transmission technology is now available, it will still invert and generate electricity at the end of consumption. For example, the two ± 800 kV high-voltage DC transmission lines in Zhejiang convert DC into AC through converter stations. △ photographed by Xu Yu of Jinhua converter station

since it is AC zl X 1 is a pull rod fixing device of two plate injection molding machine, so there is frequency. The frequency of AC in China is 50Hz, which is an experimental motor brain. It can't be on the national unified standard, just like the high-speed railway to run on the road, it also needs to "train on the same track"

the electrical frequency determines the speed of the generator in operation. The worm gear and worm of the generator set B incorporated into the electrical operation are loose, and they receive the unified dispatching of electricity, so that the total power generated by the generator set is dynamically consistent with the total power of social electricity, so as to achieve the purpose of generating as much electricity as it needs

in electric operation, there is a very important rule:

if the input electricity is greater than the output electricity to the user, the electrical frequency and voltage will rise, and vice versa. The rapid change of electric frequency causes the change of generator speed, and tells the unit control system to quickly adjust the steam inlet and water inlet. If the speed is slow, increase the steam intake and water inflow; The speed is fast, reducing the steam inlet and water inlet, so as to maintain the balance of power generation and consumption

well, there is a problem. As a power generation enterprise, it must want to generate more power and make more money when there are abundant resources, and less power when there are few resources. Why must it accept unified dispatching

for example, a power plant is short of resources recently and wants to generate less electricity, so it accidentally cut off the fuel and the steam turbine has no steam input. At this time, as long as the generator is not disconnected from the electricity, the generator instantly takes off the mask, changes the motor in seconds, reversely drives the turbine to rotate, and even causes damage to the end pole blades of the turbine, which will cause great losses

not only that, at the moment you use electricity, you have to pay electricity bills. Which power plant will do such things that harm others and oneself

of course, as a civilized and law-abiding market subject, electricity and power generation enterprises abide by the agreement and implement unified dispatching, so that they can generate as much as they use

02 however, electricity can also be stored now

immediate use is an ideal state. In some periods of time, when the power supply of local areas is insufficient, the energy storage power station can be used as a supplement

photovoltaic, wind power and hydropower are all affected by the climate. They can provide more energy than needed for electricity in sunny days (daytime), windy days and flood seasons, but they may not be able to meet electricity demand in rainy days (night), windless days and dry seasons

it's like when there is no electricity, you can charge it with the energy stored in the power bank. The energy storage of electric power is to store the electricity generated in the abundant period in the form of super large power bank

at present, the main energy storage methods include battery energy storage, pumped storage power station, etc. Pumped storage power stations use the principle of peak power generation and low power consumption. During the peak of power consumption in the daytime, a large number of hydropower stations generate electricity and transmit it to electricity for users to use; In the low power consumption period at night, the hydropower station helps to consume the remaining electricity on the electricity, and pumps the water from the downstream to the upstream again with a pump as the reserve energy during the peak power consumption period during the day. △ photo by Zhang Yongke of Xianju pumped storage power station

as for battery energy storage. The rechargeable bank, electric vehicle and electric bicycle batteries we use all belong to this category, but the electric energy storage is thousands of times larger than this scale

although there are many ways to store electric energy, the proportion of stored electric energy in the whole capacitance is still very small. More often, power enterprises will maintain the dynamic balance of power generation and consumption by strengthening power dispatching, comprehensively utilizing peak and valley power, and carrying out demand side response, so as to ensure the power safety of the whole society

source: Toutiao client, Zhejiang Electric e home

contribution: Taizhou company (Chen Weiyi, Cao Xiaoxiao)

editor: Wu Li

Copyright © 2011 JIN SHI