ENERCON WIND TURBINES GRID INTEGRATION AND WIND FARM MANAGEMENT
12Pages

ENERCON WIND TURBINES GRID INTEGRATION AND WIND FARM MANAGEMENT

2 preface Today, global energy supply without wind energy would be difficult to imagine. Given the ongoing rise in electricity demand, it is more than ever our responsibility to guarantee secure power supply. Wind energy has come of age and in the years ahead the development of wind energy will play a major role in the race to satisfy demand. To accomplish this, one of the vital factors will be the capability of wind technology to be integrated into existing power systems. Stringent regulations imposed by grid operators require wind turbines and wind farms to fulfil power plant properties...

3 grid integration and wind farm management enercon annular generator and grid management system Amongst other features, the annular generator is a key component in ENERCON's gearless wind generator design. This low-speed synchronous generator is directly connected to the rotor. Generator output voltage and frequency vary with the speed and are converted via the ENERCON Grid Management System to be fed into the grid. This allows rotational speed control to be optimised; the annular generator is coupled in a flexible way to the grid. By adjusting or ‘pitching’ the blades and through...

4 electrical grid compatibility Due to their control and operating mode, our wind turbines offer maximum power quality. Certificates from independent institutes confirm these qualities according to IEC Standards and FGW guidelines. The idea behind the Grid Management System is to control and regulate power feed without power peaks. During normal operation, the wind turbine actually requires no reactive power. Flickers and harmonic oscillations are negligible. Due to the Grid Management System's power electronics there is no inrush current. wide voltage and frequency ranges ENERCON's Grid...

5 power frequency control Grid frequency control is essential to ensure reliable and stable grid operation as well as to attain vital power supply quality. ENERCON wind turbines can contribute to the stabilisation of the grid by adapting power feed-in according to the present grid frequency. If a grid fault leads to temporary overfrequency in the grid, ENERCON WECs reduce their output according to the grid operator's specifications. As soon as grid frequency has been stabilised, ENERCON WECs continue normal power feed-in. The characteristics of this control system can be easily adapted to...

6 staying connected when grid problems occur Most transmission networks and ever more distribution grids require wind energy converters to remain connected to the grid in the event of grid short circuits. Like conventional power plants, wind turbines are not allowed to rapidly disconnect from the grid during voltage dips or overvoltage caused by grid problems. ENERCON wind turbines with the optional ENERCON UVRT feature have this capacity. No matter what type of short circuit occurs, ENERCON wind turbines can ‘ride through’ faults for several seconds, even if they were operating at rated...

7 grid integration and wind farm management power generation management – power regulation for maximum yield If the cumulative (rated) output of a wind farm is greater than the grid connection capacity at the point of common coupling, ENERCON wind farm power regulation ensures that the capacity is used to the fullest at all times. If one turbine in the wind farm generates less power, the other turbines are adjusted accordingly to run at a higher capacity. Optional generation management in the ENERCON SCADA system handles this automatically. bottleneck management – maximum output during...

8 enercon pdi (process data interface) Today, integration into grid control systems and a connection to network control stations is a standard requirement for wind farms in many countries. ENERCON SCADA offers different optional PDI modules which act as communication interfaces between the various systems. This enables ENERCON's SCADA system to communicate via analogue or digital interfaces depending on requirements. Certain wind farm target values can be set and status messages or wind farm measurement values can be transmitted to the grid operator. If desired, ENERCON METEO even offers...

9 grid integration and wind farm management of ENERCON wind turbines to regulate voltage, typically in respect of the wind farm's point of common coupling. Grid operators can either control voltage according to a set value or also via additional interfaces. Requirements for wind farm voltage control vary greatly. If a wind farm is for example connected to a substation, available tap changers can be integrated into the control system. In large wind farms with respective cable lengths, a control system can be used to improve reactive power demand for the contractually agreed point of common...

10 enercon main control unit (mcu) for wind power plants Individual ENERCON wind farms functioning similar to conventional power plants have successfully been in operation and integrated in existing grid structures for many years. It is more and more common to find several wind farms connected to a common central point of connection to form bigger wind power plants. Since installed power output is high, these plants usually feed power into high-performance transmission grids. ENERCON's MCU assumes centralised open-loop and closed-loop control of a wind power plant. It takes over typical...

11 grid integration and wind farm management REQUIREMENTS FOR WIND POWER PLANTS IN TRANSMISSION NETWORKS ~ Wind turbines have to be able to remain in operation without reducing performance and without time limits even with considerable voltage and frequency fluctuations. ~ If voltage dips occur due to grid problems, wind turbines have to remain connected to the grid for a defined period of time. ~ Short-circuit current power feed-in may be requested during a grid fault. Depending on the grid, the turbine has to be able to feed in primarily active or reactive power to the grid. ~ Abrupt grid...