Page 50 - Complementarity and Variational Inequalities in Electronics
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40  Complementarity and Variational Inequalities in Electronics














                           FIGURE 3.5 Rectifier circuit.


                           and reads here as follows:

                                                ⎧
                                                              (i 4 ),
                                                ⎪ −V 4 ∈−∂ϕ D 4
                                                ⎪
                                                ⎪
                                                ⎪
                                                ⎨             (−V 3 ),
                                                     i 3 ∈−∂ϕ D 3
                                                              (i 1 ),
                                                ⎪
                                                ⎪ −V 1 ∈−∂ϕ D 1
                                                ⎪
                                                ⎪
                                                              (i 2 ).
                                                ⎩
                                                  −V 2 ∈−∂ϕ D 2
                              At equilibrium, the dynamical circuit in Fig. 3.3 reduces to the circuit in
                           Fig. 3.5, and the stationary solutions of (3.9)–(3.11) satisfy the problem
                              ⎧
                                 −1
                              ⎨     V + By L = 0,
                                RC 1
                                                                                     (3.12)
                                 Ny L + CV + Fu,v − y L  +  (v) −  (y L ) ≥ 0, ∀ v ∈ R .
                              ⎩                                                 4
                              From the first equation of (3.12) we deduce that V = RC 1 By L , so that
                                               y = (N + RC 1 CB)y L + Fu,
                           and our problem reduces to the variational inequality VI(M, ,Fu):
                                    4
                                                                                4
                              y L ∈ R : My L + Fu,v − y L  +  (v) −  (y L ) ≥ 0, ∀ v ∈ R ,  (3.13)
                           with
                                                         ⎛                 ⎞
                                                            R  −1   R   0
                                                         ⎜ 1    0   1      ⎟
                                                         ⎜
                                                                           ⎟.
                                                                       −1 ⎟
                                                         ⎝ R   −1   R   0 ⎠
                                        M = N + RC 1 CB = ⎜
                                                            0   1   0   0
                           Let us now consider the stabilizer block as in Fig. 3.6.
                              We denote by V E , V C , and V z the voltages of the transistor and the Zener
                           diode, respectively, as indicated on Fig. 3.6. Note that we omit the capacitor C 2 ,
                           thanks to the equilibrium, and use the other notation indicated on Fig. 3.6.The
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