This lesson covers the derivation and understanding of machine equations, with a focus on Direct Current (DC) machines. It starts with the continuation of the machine equations derived in the previous lesson, explaining the expressions for a four-coil primitive machine. The lesson then delves into the system description in the optional impedance form. It further explains the concept of self-impedance, mutual impedance, and speed EMF terms. The lesson also covers the description of a DC machine, explaining the field winding, armature, and the role of brushes. It also discusses the concept of a pseudo stationary coil and how it affects the machine description. The lesson concludes with the derivation of the electrical system equation for the DC machine and the concept of large signal models and small signal models.
00:11 - Introduction
02:58 - Explanation of the synchronized reference frame description and the orientation of the reference frame
05:03 - Explanation of the machine equations and the stator vector matrix stator voltage vector
08:19 - Explanation of the space vector for the stator voltage, rotor voltage, stator currents, rotor currents, stator flux, and rotor flux
40:00 - Explanation of the rotor of the synchronous machine and the difference between the rotor of the induction machine and the synchronous machine
43:00 - Discussion on the cylindrical rotor of a synchronous machine and how the field winding is done
- In a four-coil primitive machine, there are two real coils fixed in space and two factious coils which are stationary.
- The DC machine consists of a field winding and an armature, with the armature behaving like a pseudo stationary coil due to the arrangement of brushes.
- The electrical system equation for the DC machine can be derived using the concepts of self-impedance, mutual impedance, and speed EMF terms.
- Large signal models are used to study the response of a system to a large voltage, while small signal models are used for close loop control of a system.