The operating frequency of the ac2 drive in the wind turbine electric pitch system can reach 8 kilohertz. The actual working performance parameters are rated at 48V and the maximum current is 450A. In actual use, it is powered by a 60V DC regulated power supply. The operating frequency is 8 kHz, the output voltage is 3-phase 29V, and the frequency range is from 0:06 to 56 Hz.
Power plants are divided into thermal power plants, hydroelectric power plants, wind power plants and nuclear power plants.
Thermal power plant is a factory that converts the chemical energy of fuel into electrical energy. The production process is to use the chemical energy of the fuel to make the boiler generate steam. The steam enters the steam turbine to do work, pushing the steam turbine rotor to rotate, converting thermal energy into mechanical energy. The rotation of the steam turbine drives the generator rotor to rotate, and the mechanical energy is converted into electrical energy in the generator.
Hydroelectric power plant is a factory that converts the potential energy and kinetic energy of water into electrical energy. The energy of water is used to drive the turbine to rotate, which then drives the generator to generate electricity.
Nuclear power plants use nuclear fission energy to convert into thermal energy, and then convert the thermal energy into electrical energy according to the power generation method of thermal power plants. It uses nuclear reactors and steam generators to replace boiler equipment.
According to the status and role of the power system where the substation is located, it is divided into hub substation, intermediate substation, regional substation and terminal substation.
The hub substation is located at the pivot point of the power system and brings together multiple power supplies with voltage levels generally ranging from 330 to 500KV. Once a power outage occurs, it will cause a large-scale power outage, causing the entire system to be derailed or even paralyzed, which plays an important role in the stability and reliability of the power system operation.
The intermediate substation brings together 2 to 3 power supplies and several lines. The voltage level is generally 220 to 330KV. The high-voltage side plays the role of exchanging power or segmenting long-distance transmission lines. At the same time, it reduces the voltage of a Regional power supply. A power outage across the entire site will cause the regional power grid to be disconnected. It mainly plays the role of intermediate link in the power system.
The voltage level of regional substations is generally 110~220KV. They mainly supply power to users in a region and are the main substations of a region or a small or medium-sized city. Once a power outage occurs, the power supply in the region or city will be disrupted or even interrupted.
The terminal substation is located at the end of the distribution line, close to the load. The voltage level is generally 35 to 110KV. After voltage reduction, it directly supplies power to users.