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Sliding Mode Control of Wind Energy Generation Systems Using PMSG and Input-Output Linearization. Xiangjun Li, Wei Xu, Xinghuo Yu and Yong Feng RMIT University, Australia. Background. Introduction to PMSG. Input-output linearization. SMC design. Simulation studies. Outline.
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Sliding Mode Control of Wind Energy Generation Systems Using PMSG and Input-Output Linearization Xiangjun Li, Wei Xu, Xinghuo Yu and Yong Feng RMIT University, Australia
Background. Introduction to PMSG. Input-output linearization. SMC design. Simulation studies. Outline Platform Technologies Research Institute
We need the energy supply to be sustainable!!! Background Platform Technologies Research Institute
Background Fig. 1. The future smart grid (http://energyinformative.org/what-is-the-smart-grid/) Platform Technologies Research Institute
Background Fig. 2. The installed capacity of wind generation. Platform Technologies Research Institute
Several factors have made wind power generation cost competitive: The improvement of aerodynamic efficiency of wind turbine; The potential market and government incentives; New control schemes for the variable-speed wind turbine which allow the optimization of wind turbine performance. Background Platform Technologies Research Institute
Constant speed system. Require sturdy mechanical design; Require stiff power grid. Variable speed wind energy generation. Is able to optimize wind energy absorption; Smooth power output. Background Platform Technologies Research Institute
PMSG Magnetic induction of electric current Force on current carrying lines Fig. 3. The rationale and structure of PMSG. Platform Technologies Research Institute
PMSG Fig. 4. Mechanical configurations. Platform Technologies Research Institute
PMSG Fig. 5. Application of PMSG in wind energy generation. Platform Technologies Research Institute
Permanent magnetic synchronous generator is a type of generator in which the excitation field is generated by permanent magnet; The mechanical frequency matches the required electrical frequency. PMSG requires less parts than other generators such as induction generator. Thus, it is more mechanically reliable. PMSG is widely used in wind energy generation and hydro electricity generation. PMSG Platform Technologies Research Institute
By field orientation control (FOC), it can operate the optimal working point and minimize the losses in generator and power electronic circuit; The use of a multi pole synchronous generator (large diameter synchronous ring generator) can give direct drive function without a gearbox; Higher efficiency for no additional power supply for the magnet field excitation; Higher reliability due to the absence of mechanical components such as slip rings, lighter and therefore higher power to weight ratio. PMSG Platform Technologies Research Institute
The control schemes depend on the accurate generator parameter, which vary with temperature and frequency; The permanent may increase the price of machine and meet with demagnetization phenomenon; The power factor of machine cannot be adjusted easily. PMSG Platform Technologies Research Institute
PMSG Fig. 6. The electrical configuration of the PMSG. Platform Technologies Research Institute
Problem Description Fig. 7. Signal flow chart of the system. Platform Technologies Research Institute
This page is only for you to keep in mind about the relationships of those signals The arrow means “determined by” Platform Technologies Research Institute
Problem Description Wind power intensity Mechanical power of wind turbine Performance coefficient Tip speed ratio Optimal angular frequency Platform Technologies Research Institute
Problem Description PMSG model Electrical: Mechanical: Platform Technologies Research Institute
Problem Description PWM converter algebraic model DC link algebraic model The grid side model is the symmetrical. Platform Technologies Research Institute
Problem Description Voltage of the capacitor Angular velocity of the rotator Machine side current in d-q axis Grid side current in d-q axis Platform Technologies Research Institute
Problem Description , Platform Technologies Research Institute
PMSG Platform Technologies Research Institute
Input-Output Linearization Platform Technologies Research Institute
Uncertainty Analysis is independent of Platform Technologies Research Institute
Uncertainty Analysis Platform Technologies Research Institute
SMC Design Platform Technologies Research Institute
SMC Design Theorem 1. System (1) can be stabilized by the control laws where if where is the th item of matrix , and , , are positive constants. Platform Technologies Research Institute
By choosing the uniform control gain for all subsystems , the coupling between them through uncertainty items can be decoupled. After the decoupling, the stability of the overall system can be achieved by stabilizing each subsystem. Here we only carry out the simulation study of the subsystem , which is the angular speed of the rotator. The units of the variables are unified. The angular speed and the angular acceleration are two states depicted in Figure 8 and Figure 9. Simulation Studies:Sub-system Platform Technologies Research Institute
Simulation Studies:Sub-system Fig. 8. State trajectory of the closed-loop system. Platform Technologies Research Institute
Simulation Studies:Sub-system Fig. 9. System response of the closed-loop system. Platform Technologies Research Institute
The structure of the wind energy generation system using PMSG has been introduced. The system, which is described by mathematical model in state space, has been formulated and linearized by the input-output linearization technique. Uncertainties are included in the modeling and linearization. SMC controls have been designed to stabilize the system. Simulation studies are conducted to verify the results. Conclusion Platform Technologies Research Institute
Thanks for your attention! Questions please. Platform Technologies Research Institute