The curves of Fig. A.4 allow to match input filter design to SSPC rating. As example a linear SSPC with technical data extracted from Reference [2] is considered now. When the input filter shall have a damping coefficient of <5=0.1 the maximum value of the capacitor is according to Fig. A.4: C=2.3 ■ C0 = 384mF. This, however, stipulates that according to (1.4) the inductor must have a value of at least L = 230//H. Table I exhibits for <5=0.1 a voltage overshoot of 73% (for a mechanical relay contact) which is unacceptably high. It is therefore important to verify the SSPC dedicated voltage overshoot which can be performed by means of (2.32). The result is: 0.0473 • 73% = 3.45% which is extremely low and underlines the excellent properties of the linear SSPC. Although the ‘no load case' was excluded from the previous considerations, it shall be mentioned that (2.17) approaches for R—>x (i.e. K=0) the limit value of CL—2 ■ TfIl/U0 (apply Bernoulli/L'Hospital). This means that the considered 5 Amp switch is able to charge a single capacitor of CL=400uF without tripping. Finally it is of interest to determine the shape of input current and output voltage when the SSPC leaves the limitation mode and goes back in the saturation mode. In order to investigate this case, Fig. A.3 is considered again, however, with the following initial conditions:
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