DC motors advantages and disadvantages over AC motors
The power of AC has turned out to be well known and advantageous on account of simple generation, transmission with fewer losses to long distances due to stepping up voltage & stepping low voltage to the desired level. In industries 70% of the motors and drives used are Induction motors, hence AC motors in general means induction motors. Due to the advantages of its rugged construction, Induction motors were preferred in industries, less maintenance and can be operated in explosive atmospheres also. So these motors ruled out all the motors in industries in each application. But DC motors were still used in where induction motors cannot fulfill the need. so, DC motors have their importance in industries. This is because of some special characteristics they possess.
Advantages of DC motors:
Speed can be control over a wide range both above and below the rated speed: The attractive feature of the DC motor is that it offers the wide range of speed control both below & above the rated speeds. This can be got in DC shunt motors by methods such as armature control method and field control method. DC motors are widely used in fine speed applications such as in rolling mills and paper mills.
Strong starting torque: DC arrangement engines are the most appropriate drives for electrical footing applications utilized for driving overwhelming burdens in beginning conditions. DC series motors will have a starting torque as high as 500% compared to normal operating torque. Therefore DC series motors are used in electric trains and cranes.
Accurate steep less speed with constant torque: Constant torque drives are one such the drives will have motor shaft torque constant over a given speed range. In such drives, shaft power varies with speed.
Quick starting, stopping, reversing and acceleration
Numerous components which make DC engines progressively favorably contrasted with air conditioning acceptance engines.
Reactive power consumption
Disadvantages of DC motors:
High starting expense
Increased activity and upkeep cost because of the essence of commutator and brush gear
Can’t work in unstable and dangerous conditions due to starting to happen at brush (a chance in replacement disappointment)
General comparisons
DC engines have the benefit of: higher beginning torque, snappy beginning, and ceasing, reversing, variable paces with voltage information and they are simpler and less expensive to control than AC.
Air conditioning engine favorable circumstances include: lower power request on begin and negligible upkeep. While the market for AC engines is bigger than DC, it tends to challenge discover AC arrangements with fractional horsepower appraisals.
DC applications
Demand is developing for 12 and 24V engines to help solar, marine and portable (truck-mounted) hardware which DC innovation promptly bolsters. DC innovation is more financially savvy than AC all in all for lower horsepower applications. DC engines are the more seasoned of the two innovations, yet R&D has not finished. Engine companies keep on putting resources into innovation to lessen upkeep expenses and broaden engine life
