PitchServoRHS:
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Pitch servo model.
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Form:
betaDot = PitchServo( beta, t, d )
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Inputs
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beta (1,1) Pitch angle
t (1,1) Time (not used)
d (1,1) Data structure
.k (1,1) Forward gain
.betaLimit (1,1) Maximum beta
.betaRateLimit (1,1) Maximum beta rate
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Outputs
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betaDot (2,1) Beta rate
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Reference: Gill Estevez, P. ,"Model Dinamico de Una Turbina
de velocidad variable con Generador de Imanes Permanentes y
control de angulo de calaje ? Analisis de Control de
Velocidad. Figure 6.
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