cameroon gce advanced level 2025 fundamental and power electronics 2

 

Section A

 

1. AC CIRCUITS

 

Consider the circuit in Figure 1. The values of the circuit elements are:

• R = 60 $\Omega$
• L = 318.4 mH
• C = 15 $\mu$F
• e(t) = 200$\sqrt{2}$ sin(100t) V

1.1 Determine the complex expression of the circuit impedance Z. (3 marks)

1.2 Determine the complex expression of the current I(t), I. (3 marks)

1.3 Determine the complex expression of the current I${1}$(t),I${1}$. (3 marks)

1.4 Deduce the complex expression of the current I${2}$(t),I${2}$. (3 marks)

1.5 Calculate the phase angle between the voltage and the current $\varphi$. (2 marks)

1.6 Calculate the power consumed by the circuit. (3 marks)

1.7 Sketch the phasor diagram of the circuit. (3 marks)

2. DIODE CIRCUITS

Consider the circuit in Figure 2. The circuit parameters are:

• R = 100 $\Omega$
• Dz: V${Z}$ = 6.2V, r${Z}$ = 0 $\Omega$

2.1 Load regulation

The input voltage to the regulated power supply is constant; E = 24V.

2.1.1 Determine the value of the current labeled ‘I’. (2 marks)

2.1.2 Determine the minimum and maximum values of I$_{Z}$. (3 marks)

2.1.3 Deduce the minimum and maximum values of I$_{L}$. (3 marks)

2.1.4 Deduce the minimum and maximum values of R$_{L}$ required for stabilization to be maintained. (3 marks)

2.2 Line regulation

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