© 2017 solidThinking, Inc. Proprietary and Confidential. All rights reserved. An Altair Company DC MOTOR WITH ELECTRICAL EXCITATION STARTING WITH VOLTAGE RAMP • ACTIVATE solidThinking © 2017 solidThinking, Inc. Proprietary and Confidential. All rights reserved. An Altair Company PMDC Motor A shunt DC motor connects the armature and field windings in parallel or shunt with a common D.C. power source. This type of motor has good speed regulation even as the load varies, but does not have the starting torque of a series DC motor. DC Motor whose poles are made of Permanent Magnets is known as Permanent Magnet DC (PMDC) Motor. The magnets are radially magnetized and are mounted on the inner periphery of the cylindrical steel stator. The stator of the motor serves as a return path for the magnetic flux. The rotor has a DC armature, with commutator segments and brushes. The Permanent Magnet DC motor generally operates on DC supply obtained from the batteries or rectifiers. The interaction between the axial current carrying rotor conductors and the magnetic flux produced by the permanent magnet results in the generation of the torque. • ACTIVATE solidThinking © 2017 solidThinking, Inc. Proprietary and Confidential. All rights reserved. An Altair Company Electrical Excitation In the case of a machine with field coils, a current must flow in the coils to generate the field, otherwise no power is transferred to or from the rotor. The process of generating a magnetic field by means of an electric current is called excitation. For a machine using field coils, which is most large generators, the field current must be supplied, otherwise the generator will be useless. Thus it is important to have a reliable supply. Although the output of a generator can be used once it starts up, it is also critical to be able to start the generators reliably. In any case, it is important to be able to control the field since this will maintain the system voltage. • ACTIVATE solidThinking © 2017 solidThinking, Inc. Proprietary and Confidential. All rights reserved. An Altair Company Voltage Ramp The ramp voltage is fed to the signal voltage of the Permanent magnet dc motor, where the voltage is fed to the motor and then the mechanical output of the rotor is connected to the inertia block and then to the quadratic dependent speed torque. The ramp voltage drives the motor and the mechanical inertia load is connected to the torque and the current flowing through the motor is also measured. A voltage ramp is applied to the armature, causing the DC machine to start, and accelerating inertiasagainst load torque quadratic dependent on speed, finally reaching nominal speed. • ACTIVATE solidThinking © 2017 solidThinking, Inc. Proprietary and Confidential. All rights reserved. An Altair Company Circuit Topology • ACTIVATE solidThinking © 2017 solidThinking, Inc. Proprietary and Confidential. All rights reserved. An Altair Company Output Waveform • ACTIVATE solidThinking © 2017 solidThinking, Inc. Proprietary and Confidential. All rights reserved. An Altair Company Conclusion PMDC motor is extensively used where small DC motors are required and also very effective control is not required, such as in automobiles starter, toys, wipers, washers, hot blowers, air conditioners, computer disc drives and in many more. Thus the PMDC with Electrical excitation starting with the voltage ramp source is implemented using the Activate tool. • ACTIVATE solidThinking.