Electric motors of direct current

Electric motors of direct current
DC motor - a device that is designed for converting DC electrical energy into mechanical work.
A DC motor is used where a large range of speed control is needed, and greater accuracy in supporting the speed of rotation and controlling the speed "up" from the nominal.
  • steel frame with an excitation winding mounted in a coil;
  • An anchor (which consists of a core and a collector);
  • housing with bearings;
  • brushes (with which voltage is applied to the armature circuit).
DC motors according to the nature of the excitation are divided into the following four types:
  • DC motor with independent excitation;
  • DC motor with parallel excitation;
  • DC electric motor with consistent excitation;
  • DC electric motor with mixed excitation;
  • DC motor with excitation from permanent magnets.
Consider each type of excitation separately:
  1. Independent excitation - the excitation winding is connected to an external power source, and the armature winding is connected to the main one. Turnovers are adjusted by the resistance of the armature windings. Electric motors with independent excitation must not be started without load, since its speed will increase sharply and the engine will fail.
  2. Parallel excitation - field windings and rotor windings are connected in parallel with one current source. In this case, the field current is much lower than the rotor current.
  3. Serial excitation - the excitation winding is connected in series with the rotor windings, as a result of which, the windings pass the same current. It is forbidden to start the engine without load.
  4. Mixed excitation - involves the use of two field windings, which are located in pairs at each pole of the motor. As a result, the engine will have characteristics such as engines with parallel or series excitation.
Advantages of DC motors:
  • Small overall dimensions;
  • Easy control;
  • Simple design;
  • Possibility of use as current generators;
  • Quick start, especially characteristic for motors with a serial drive circuit;
  • Possibility of smooth regulation of shaft rotation speed.
Disadvantages of DC motors:
  • For connection and operation it is necessary to buy a special DC power supply;
  • High price;
  • The presence of consumables in the form of electrographic, copper-graphite, carbon-graphite and silver-graphite brushes;
  • The collector wears out;
  • Need periodic maintenance.
Scope of application:
  • Woodworking machines with CNC;
  • Metalworking machines with CNC;
  • Robots and manipulators;
  • Household appliances;
  • Automotive industry;
  • Aircraft industry;
  • Electric vehicles;
  • Electric locomotives;
  • Trams;
  • Electric trains;
  • Trolleybuses;
  • Lifting-transport mechanisms;
  • Kids toys;
  • Industrial equipment with the need for speed control over a wide range.
As the owner of Siemens electric motors, Baumyuller (Baumüller) or other brands, you can choose cost-effective equivalent or equivalent, in the following sections:
  • High-moment electric motors - MT, MTA;
  • Electromotors - МР112, МР132, МР160, МР225;
  • Servomotors - PI, PC, 3PI, PIK.