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Generator separately excited by battery Self exciting generators Series on left, shunt on right. A shunt generator is a type of electric generator in which field winding and armature winding are connected in parallel, and in which the armature supplies both the load current and the field current for the excitation (generator is therefore self excited).
A shunt is a device that is designed to provide a low-resistance path for an electrical current in a circuit. It is typically used to divert current away from a system or component in order to prevent overcurrent .
a shunt, the simplest design, uses the main winding for the excitation power; an excitation boost system (EBS) is a shunt design with a separate small generator added to temporarily provide an energy boost when the main coil voltage drops (for example, due to a fault). The boost generator is not rated for permanent operation;
Bipolar generators were universal prior to 1890 but in the years following it was replaced by the multipolar field magnets. Bipolar generators were then only made in very small sizes. [1] The stepping stone between these two major types was the consequent-pole bipolar generator, with two field coils arranged in a ring around the stator.
The critical field resistance is defined as the maximum field circuit resistance (for a given speed) with which the shunt generator would just excite. The shunt generator will build up voltage only if field circuit resistance is less than critical field resistance. It is a tangent to the open-circuit characteristics of the generator (at a given ...
A compound DC motor connects the armature and fields windings in a shunt and a series combination to give it characteristics of both a shunt and a series DC motor. [5] This motor is used when both a high starting torque and good speed regulation is needed. The motor can be connected in two arrangements: cumulatively or differentially.
Shunt winding was used experimentally, in the late 19th century, [8] but was impractical owing to problems with commutation. Various schemes of embedded resistance, inductance, and antiphase cross-coupling were attempted to reduce this. Universal motors, including shunt wound, were favoured as AC motors at this time as they were self-starting. [4]
The term back electromotive force is also commonly used to refer to the voltage that occurs in electric motors where there is relative motion between the armature and the magnetic field produced by the motor's field coils or permanent magnet field, thus also acting as a generator while running as a motor. This effect is not due to the motor's ...