Product Name :Direct drive wind power experiment platform solution
    Update Time :2012.09.18 Product Unit : Browsing Number :

Direct drive wind power experiment platform solution

The basic principle of the direct drive wind power
  The direct drive wind power generation system using wind machines and permanent magnet multi-pole synchronous generator directly coupled, eliminating the need for a gearbox, permanent magnet multi-pole synchronous generator rotor permanent magnet structure, eliminating the need for external excitation power. Issued by the permanent magnet multi-pole synchronous generator wind turbine frequency changing AC inverters transform into constant frequency AC power grid, the electricity generated must be fed into the grid through the inverter through a dc rectifier rectifier, the inverter capacity and wind power generation capacity of the system is the same. In the composition and role of the direct drive wind power system in Figure 1 shows, the converter and the control part as follows:
  Figure 1  direct drive wind power system main circuit topology

Research Xu direct drive wind power experiment platform performance analysis and control program   
    Issued by the energy of permanent magnet synchronous generator (PMSG) by three-phase rectifier bridge controlled rectifier is converted to DC, the intermediate DC bus in parallel capacitance from the regulator and the role of energy storage buffer, and finally converted to the grid grid-connected PWM converter with the frequency of the alternating current fed into the grid, the control scheme shown in Figure 1.Specific run, the rectifier bridge to convert the energy permanent magnet synchronous generator to direct current, grid-connected PWM converter using directional vector of the grid voltage, the DC inverter for the good of the sine wave-shaped grid and the active /reactive power decoupling . By grid-connected PWM converter, the DC bus voltage control, energy flow is the flow to the power grid, from PMSG PMSG and work in the normal state of power generation.

The diode bridge rectifier and the PWM converter advantage:
Diodes have a smaller conduction losses, the price is lower than the IGBT, a relatively simple structure and control, effectively reduce the cost and loss of the entire system, the network side current sinusoidal.
The diode bridge rectifier and the PWM converter shortcomings:
DC bus voltage can not be achieved the flexibility to control the output voltage will change with the change of the generator speed, not the sine of the stator current, the system can not work at full power to transform state.

Figure 2  direct drive wind power system to run the control program
Research Xu direct drive wind power experiment platform system architecture shown in Figure 3.
<l> The YX direct drive wind power experiment platform using a VVVF three-phase induction motor driven by a three-phase permanent magnet synchronous generator running, asynchronous motor and synchronous generator is installed on a base, using the coupling is connected tooptical absolute power encoder measuring the real-time speed of the motors, permanent magnet synchronous generator number of poles is 8 pole three-phase induction motor control inverter is used to control speed to simulate wind speed, while computer-controlled frequency to implement the three-phase induction motor speed regulation to simulate the fan output.
<2> the grid side converter using IPM modules or IGBT modules are built using the two-unit module design (a total of three groups, Unit 2, module), the IPM module or the withstand voltage of the IGBT module 1200V, the current is about 150A. Dc link capacitor 450V electrolytic capacitor two series in order to improve the pressure.
<3> and the network transformer requirement is three-phase transformer, its capacity requirements greater than the maximum generator capacity, capacity 15KVA about.
 <4> grid side converter using DSP control, DSP control board of research Xu TMS320F28335, and IPM power board (IGBT module, the DSP control board and the connection of the IGBT module driver board requires research Xu IGBT six units). 
<5> in this experimental system using optical encoder acquisition generator rotor position and velocity, optical encoder installed in the generator back-end output shaft; Hall voltage and current sensors to collect the DC side and grid side voltage and current signals, the sensor range based on system capacity to choose to install.
<6> research Xu YX-XDS510 emulator to complete the debugging of the control algorithm.

Figure 3  research Xu direct drive wind power system structure

Simulation platform kind renderings

Research Xu direct drive wind power the experimental platform for system configuration and cost (see table)

Schedule 1 (for reference only)