Chinese-Hisuppliers.com, a trade directory of China products, China manufacturers, China suppliers, China exporters

Industry Information >>Energy & Power>>On the grid with wind farms out of the clearance operation

On the grid with wind farms out of the clearance operation

Wind power is application of modern technology on a large-scale wind energy resources development and utilization of an initiative. At present, the developed countries of the world's wind power has already been put into commercial production stage, some of the production of electricity has become an important part of. California, a total installed capacity of wind power up to 134 × 10'kW, Urumqi is the power grid with a total capacity of twice. Xinjiang's Dabancheng wind energy and wind power network with a total installed capacity for wind turbine 2050kW, since October 1989 and formally to the grid in June 1990 electricity transmission grid to a total of 370 × 10'kW. h, the average stand-alone operation has reached a few hours, 4500 hours, the whole year is expected to be sent to the electric power grid 470 × 10'kW h, running up more than 6000 hours. The economic benefits of wind power has also attracted attention, the United States and Denmark joint venture to build the wind farm not only water and electricity, nuclear power construction period short, quick recovery of investment, but also the cost of generating electricity with oil, nuclear power about the same ( 1987 U.S. wind power market cost of power generation only 7 to 8 cents / kW.h).

These facts are all the people that wind power and electric power systems can be run to make full use of natural renewable energy for mankind for more power.

On the following wind and wind power and the power grid and the operation of the network described below.

First, what is meant by wind power

The wind farm is in English "Windmil Fi-eld" or "Wind Fafm", it is meant that a large number of wind turbine installation in the wilderness on the hillside, under the unified management of the computer from several dozens or even hundreds of Taiwan or Taiwan The multi-network and run the wind turbine power transmission grid to the group's driving force. For example, wind energy's Office of the Xinjiang Dabancheng water wind farm is located 35km away from the Urumqi Dabancheng wind zone, run by the network of 14 wind turbines to the group after a boost with the Urumqi 35kV main network striata Liu line to connect power grids Power supply.

Wind farm on the Main Line

The main knot wind power lines can form, of a wind machine and a step-up transformer connection, the Typhoon is a multi-machine power with a step-up transformer connections, according to the wind farm with a total capacity of the size and distance power grid The distance can be divided into a step-up or step-up secondary.

Dabancheng wind farm in Xinjiang, we adopt the six-power Typhoon aircraft share the same blue, in order to take full advantage of wind energy, wind turbine must be between a certain distance, the wind in determining the main junction in line transformer location to be careful in the following two : (1) the laying of cables of the economy, (2) the force of Typhoon aircraft to the cable between the transformer impedance as close as possible to that of wind power transformer for the special box-type transformers placed in the open air, transformer and control box together, High-low round in the side of the transformer and the protection of the internal control box, so that rain and dust and improve the working environment.

Third, on the wind monitoring system

As the stand-alone wind power capacity of the small number, in order to ensure that the Typhoon aircraft for the safe operation of power, wind power has been installed with advanced computer monitoring system, which generally on the spot by monitoring (LCS) and the Central Monitoring (CMCS remote control) consists of two parts , In situ monitoring functions include the following:

(1) can run from the control panel on the spot before the computer screen that all the wind machine operation, such as: the Department wind turbine wind speed, voltage generator, current, power factor, spindle speed, gear boxes and bearings Temperature, and so on.

(2) can be set to control the keyboard, easy to modify the wind turbine is scheduled to protect the value of over-voltage protection, such as setting the scope of the protection of frequency tuning range, speed limit changes, and so on.

(8) of the control system can be detected according to their wind speed, wind direction and the situation automatically start looking for direction (that is, automatic yaw) or down control orders, while self-diagnosis of the existence of wind turbine failures need downtime. The system can detect on the grid, found voltage, the frequency of irregular work immediately shut down power grids to be back to normal after the automatic start-up.

(4) The control system has a record of the advanced features that can record all occurred in the failure or abnormal operation, and told staff to run a fault. The system can also carry out production of the report, to record the wind turbine on the power generation, and a total generating capacity and operating hours.

Central control system in the control room, that we can monitor the whole edge of Typhoon the wind machine operation. In addition to host the central control system, there are a set of back-up equipment, the host for the failure of the investment, two computers equipped with printers, may at any time to provide the necessary people.

Fourth, with regard to the power grid with wind power and the network process

Since the induction generator and network than a simple synchronous generator and will not have a network and vibration and out-of-step, so the wind turbine at home and abroad are basically using asynchronous generators. Stand-alone wind turbine capacity has been the development of the previous 10 ~ 30kW ~ 0 current 150 ~ 400kW, in the grid method, the direct method due to network and to have a greater impact on current-voltage power grid caused by an instant drop that has not been adopted At present, more advanced methods on the ground and two-way network of silicon and software to control input method, which makes large-capacity wind turbine and wind power and the power grid and network operation possible. Its working principle is as follows: when the round by the wind-driven generators to spin close to synchronous speed when (synchronous speed depends on poles on the grid frequency and number), the export of air generator switch closed, so that by generating a set of silicon with two-way Systems, the SCR control bidirectional angle from 180. 0 to gradually open the two-way silicon-on angle from 0-180. A gradual increase in the electrical grid in the early stages of instantaneous induction motor as a generator is running, which tend to slip gradually to zero, due to deterioration and two-way silicon-on angle of the restrictions, and when the net impact is very small, Can be a very smooth process and to network, with the increase speeds in excess of speed synchronization, the beginning of the electrical transmission grid to power, the greater the wind, electrical machinery gained more power, the greater the deterioration of the absolute value, the electricity The more, generating zero slip a two-way silicon switch was a group of short, thus putting an end to wind turbines and the network, but also the beginning of the power grid to the power generation process.
 

Fifth, on the wind power output characteristics

Wind speed of the random use of wind energy is one of the factors, along with the development of wind power, wind power and run record and collate the information, be raised as to the changes of wind speed has been more and more profound understanding of Therefore the use of meteorological data to forecast the wind power output generally is not very difficult. With the winds of change then the wind farm's output is how to change it? Us that the wind farm output that is, each change in wind turbine output change.

Wind wind turbine impeller in the maximum power available for 1/2V s11 which q impeller for maximum efficiency and value to 0.593, p for the air density for the A wind swept the area, the length of the blade by the decision to wind speed V

From the style is not difficult to see in the wind turbine has been made, the wind turbine impeller from the maximum power of the wind speed and power is a function of 8, except for the mechanical wear and tear and wear and tear generators can be similar to that of the output of the generator is a wind speed of Function, but in the actual operation of the generator output and the relationship between wind speed is not that simple, it involves complex aerodynamic theory, to a certain wind speed, we can use these formulas to describe the wind turbine output of the process of change , With the wind speed to increase the output power has sharply increased, at the same time electromagnetic torque increases, the interaction between the two so as to achieve a dynamic balance, because of the existence of electromagnetic torque, and its aerodynamic characteristics, wind turbine More than its rated speed after the output has become smooth and the wind speed increased output declined slightly in the wind before the wind turbine rated output power is the wind speed increases

Increased. From The wind speed on changes in the curve, we can see that the wind speed is the time to some of the changes in the scope, meaning that the wind power output in a single day a certain inherent within the scope of the changes, but the system load changes and Changes in wind speed can not be determined from this sense, the wind power output of random changes in the power grid is not conducive to the operation, when the wind power capacity could be greater use of wind energy storage water power station to the grid so that the balance of power (wind When multi-pumping energy storage, the use of wind-hour pumping the water can be stored potential energy of the multi-generation). According to research data show that wind power capacity of not more than 5% of the power grid capacity, this wind farm output by random changes in the hydroelectric power plant, or the speed control device to make up for the automatic adjustment, to ensure that the system in balance.

Sixth, on the wind farm reactive power compensation

The wind generator farm reactive power compensation is worthy of attention, because the asynchronous machine reactive power needed to create a magnetic field, and as the face of increasing output power, reactive power is also increasing, that is, when the wind turbine power output Is not a constant value, the reactive power needed is not a constant value.

The wind farm capacity and not from the main electrical power grids distances close to the wind power, reactive power compensation also does not seem very serious. At this point because we can rely on the power AVR for automatic adjustment. But when the wind power capacity, or more away from the grid, due to the wind than to absorb a large number of reactive power lines and caused the loss of voltage increase at the same time for the power grid in the main generator of economic operation is very negative, it is necessary to increase Reactive compensation devices installed.

The wind farm reactive power compensation can be divided into two positions: first, in the low-pressure side of the 400V capacitor for compensation, so as to reduce the wind turbine between the transformer and connect the cable cross-section. Second, using high-pressure side of the compensation to focus and concentrate easy to control compensation, compensation from the point of view due to the effects of wind power is a variable reactive power, it is proposed to adopt a static VAR compensator, which is a new type of reactive power, can be smooth Reactive power output characteristic curve, by regulating the wind can make the total input of reactive power to maintain a specified value on.

VII Conclusion

Wind power and the power grid network and the production run to the wind has brought a very lively scene, but with the constant development of wind power technologies, wind power costs continue to decline, wind power capacity will increase with time, then we will Encounter many new problems, so we must conscientiously sum up the experience of running wind power, wind power for future development to lay a solid foundation for the (Water Resources Department of the Xinjiang Dabancheng wind energy company


Industry Information >> Related Artical