Consider the stream tube around a wind turbine shown in Fig. 4.1. Four stations along the flow are indicated in the diagram: station 1 is far upstream of the turbine, station 2 just before the blades, station 3 just after the blades, and station 4 far downstream of the blades. Between the stations 2 and […]
Category: Dynamic Modeling, Simulation and Control of Energy Generation
The Actual Power Coefficient and its Dependence on the Blade Setting Angle
Typically, the power coefficient Cp is expressed as [Rosas (2003) and Slootweg et al. (2003)]
The Moore-Greitzer Model Equations
The unsteady and steady fluid mechanics of the flow upstream and downstream of the compressor is considered while the viscous effects are limited to within the actuator disk of the compressor which allows one to define non-dimensional total – to-static pressure rise map. Compressibility is assumed to be confined to the plenum chamber downstream of […]
Turbine Power and Torque Outputs
The power developed by the turbine is calculated using the change in enthalpy in the working fluid. This enthalpy is based on the linearized enthalpy temperature relationship of the air and fuel entering the combustion chamber and that of the products of combustion. where Pturbine is the total power developed by the turbine, mtb is […]
The Cell Output Equations
The approach adopted by del Real et al. (2007) is indeed most suitable for control applications. However, it is important to include the proper temperature dependence of the Nernst potential in the model and ensure that the dependence of the Ohmic resistance on the membrane water content is properly parameterized. The cell voltage is expressed […]
Adaptive Kalman Filters
Reconsider the KF correction Eq. (7.7.6b) and observe that the correction is a function of the innovation sequence which is, tk = (zk – HkX-). (7.7.21) The innovation sequence is a white Gaussian noise sequence with zero mean when the filter is optimal. Moreover, the observation error and state estimation error are orthogonal to each […]
Actuator Disc Theory
Perhaps the simplest approach to the aerodynamic modelling of the wind turbine is the actuator disc theory which ignores the flow rotational effects. In this case, one may integrate the increment of the axial forces dFx, across the cross-sectional area of the turbine disc, and obtain Fx = 1 p(V1 – V4)(V1 + V4)pR2. (4.3.7) […]
Maximum Power Point Tracking and Protection Against Excessive Wind Torque
All modern wind turbines are endowed with a maximum power point control and tracking systems that ensure the optimal operation of the wind turbine. To achieve maximum conversion, the turbine must necessarily operate at an optimum tip speed ratio which to a very large extent depends on the variation of the power coefficient with respect […]