Question

3. a) A Flyback converter is operating in flux boundary conduction mode. The duty cycle is D and the turns ratio between primary and secondary sides of the transformer is $N_1:N_2$. The output voltage is $V_o$ and input voltage is $V_a$. Sketch the input current $i_s$, the diode current $i_d$ and the voltage of the MOSFET $V_{DS}$ (voltage across Drain and Source of the MOSFET). Find the expression of $V_{DS}$. b) In the same application, another option may be using two MOSFETs (T1 and T2) in series as shown in Figure 2. T1 and T2 switch simultaneously. 1) Sketch the input current $i_s$, the D3 diode current $i_d$ and the voltage of the two MOSFETs $V_{DS1}$ and $V_{DS2}$. 2) State the purpose of D1 and D2; 3) State the advantage of two series MOSFETs compared to conventional one MOSFET Flyback converter.

          3. a) A Flyback converter is operating in flux boundary conduction mode. The duty cycle is D and the turns
ratio between primary and secondary sides of the transformer is $N_1:N_2$. The output voltage is $V_o$ and input
voltage is $V_a$. Sketch the input current $i_s$, the diode current $i_d$ and the voltage of the MOSFET $V_{DS}$ (voltage
across Drain and Source of the MOSFET). Find the expression of $V_{DS}$.
b) In the same application, another option may be using two MOSFETs (T1 and T2) in series as shown in
Figure 2. T1 and T2 switch simultaneously. 1) Sketch the input current $i_s$, the D3 diode current $i_d$ and the
voltage of the two MOSFETs $V_{DS1}$ and $V_{DS2}$. 2) State the purpose of D1 and D2; 3) State the advantage of
two series MOSFETs compared to conventional one MOSFET Flyback converter.

3. a) A Flyback converter is operating in flux boundary conduction mode. The duty cycle is D and the turns
ratio between primary and secondary sides of the transformer is N1:N2. The output voltage is Vo and input
voltage is Va. Sketch the input current is, the diode current id and the voltage of the MOSFET VDS (voltage
across Drain and Source of the MOSFET). Find the expression of VDS.
b) In the same application, another option may be using two MOSFETs (T1 and T2) in series as shown in
Figure 2. T1 and T2 switch simultaneously. 1) Sketch the input current is, the D3 diode current id and the
voltage of the two MOSFETs VDS1 and VDS2. 2) State the purpose of D1 and D2; 3) State the advantage of
two series MOSFETs compared to conventional one MOSFET Flyback converter.

Added by Carla F.

Question

Please give Ace some feedback