Question 8.34: Microwave Oven Figure 8.101 shows the simplified circuit of ...
Microwave Oven
Figure 8.101 shows the simplified circuit of a microwave oven. A transformer at the voltage source increases the voltage input to 2800 V and charges the capacitor in the circuit. When the capacitor is fully charged, it supplies the voltage to the magnetron (power amplifier) together with the voltage source from the transformer. A very high input voltage is supplied to the magnetron in order to generate the microwave energy to heat the food.
The voltage input after increasing by the transformer is 2800 sin (120πt), the capacitor has the capacitance of 100 mF, and the resistance of the magnetron is 20 kΩ. Use PSpice to find the voltage across the magnetron during the charging and heating process.
First, given the voltage source, v_S(t) = 2800 sin (120πt) , the frequency is 60 Hz. Follow Example 2.24 to set up the VSIN voltage source, and follow Example 8.25 to place a diode in the circuit. The PSpice schematic solution is given in Figure 8.102.
Next, run the simulation as time transient analysis (see Figure 2.75) for 1 s, with the voltage differential markers located before and after the magnetron (see Figure 8.102). The voltage across the magnetron is shown in Figure 8.103.
