Speed Control Of DC Motor | Flux or field control - 2 | DC machines | Lec-58

TL;DR

The content discusses various speed control methods for DC series motors, including field diverter control, tap field control, and series-parallel connections.

Transcript

hello everyone in the last session we discussed about how to control the speed of the dc motor by using the flux r field now we have different types of speed control method so in this particularly we have in series motor in series motor the speed can be controlled by the following methods we have some following methods are available so first method... Read More

Key Insights

• 🧑‍🦼 Series motors have specific speed control methods designed to maintain efficiency and flexibility in operation.
• 🏑 Field diverter control is essential in reducing the current flow through the field winding, which can help control speed effectively.
• 😑 Tap field control allows for pre-determined speed settings by adjusting the effective flux via various tapping points.
• 🧑‍🦼 The series-parallel connection technique balances armature current and enables the motor to draw different levels of torque, enhancing speed characteristics.
• 🐎 Employing diverter resistors effectively manages the flow of current to maintain desired operational speeds.
• 🧑‍🦼 Adjusting flux directly influences the speed of a series motor, demonstrating the importance of field strength in motor control.
• 🐎 The relationship between ampere turns and motor speed is significant, with parallel configurations providing an advantage in torque and speed output.

Questions & Answers

Q: What is field diverter control in series motors?

Field diverter control allows the diversion of current within a series motor to reduce the effective field strength. By adding a diverter resistor, some current bypasses the motor’s field winding, resulting in a decrease in field flux and subsequently controlling the motor's speed. This method helps maintain operations below the rated speed, providing flexibility in slow-speed applications.

Q: How does tap field control regulate motor speed?

Tap field control involves connecting multiple taps at various points in the field winding. Each tapping point corresponds to a different level of flux, allowing the motor to operate at varying speeds by adjusting the current flowing through the field winding. This enables the motor to achieve different speed settings according to operational requirements and enhances overall performance.

Q: What advantages does the series-parallel connection offer for speed control?

The series-parallel connection method enhances motor performance by allowing the armature current to be split between multiple windings. This generates two sets of ampere turns, effectively increasing the motor’s torque when connected in parallel. Consequently, this method enables better management of the speed characteristics of the motor as compared to strictly series configurations.

Q: Can you explain how the ampere turns in series and parallel connections differ?

In series configurations, the total ampere turns are based solely on the series winding, while in parallel configurations, the current is split, effectively reducing the ampere turns in each winding. This difference means that the parallel configuration provides twice the torque output compared to a series setup, allowing the motor to operate at higher speeds under specific conditions.

Summary & Key Takeaways

• The session focuses on controlling the speed of DC series motors, emphasizing methods tailored for series motors.

• Key speed control methods include field diverter control, which diverts current to manage motor speed, and tap field control utilizing variable field strengths.

• Additionally, the series-parallel connection method optimizes ampere turns, balancing between series and parallel configurations to enhance motor speed.