Instructions: Formulate a detailed essay-style response to the following prompts, drawing exclusively from the provided source material.

1. Compare and contrast the structure, operation, and typical applications of the BJT, MOSFET, and IGBT power semiconductor devices based on the information provided in the source context.
2. Discuss the concept of phase-controlled converters. Explain their function, the role of the thyristor firing angle (α), and describe the operational differences between 2-pulse, 3-pulse, and 6-pulse converters.
3. Explain the impact of source inductance on the performance of a power converter. Detail how its presence affects commutation, creates an “overlap interval,” and alters the DC output voltage for both single-phase and three-phase converters.
4. Describe the three types of choppers discussed in the text: step-up (boost), step-down (buck), and step-up/down (buck-boost). For each type, explain its primary function, the relationship between input and output voltage, and the critical role of the duty cycle (D).
5. Detail the operation of a three-phase inverter. Explain the fundamental differences between the 180° and 120° modes of conduction, including how the load voltages are determined and which devices are conducting at any given time in each mode.