Types of Electric AC DC Generators
Types of Alternating Current and DIrect Current Generators.
Electric generators types depend on the type of generating equipment employed, the electrical energy produced is either direct current (DC) or alternating current (AC).
AC generators are classified as single-phase or polyphase. A single-phase generator is usually limited to 25 kW or less and generates AC power at a specific utilization voltage. Polyphase generators produce two or more alternating voltages (usually two, three, or six phases).
DC generators are classified as either shunt, series, or compound-wound. Most DC are the compound-wound type. Shunt generators are usually used as battery chargers and as exciters for AC generators. Series generators are sometimes used for street lights. The emf induced in a DC generator coil is alternating. Rectification is needed to direct the flow of current in one direction. The generator rotating commutator provides the rectifying action.
References: “Joint Departments of the Army and the Navy, Operation Maintenance and Repair of Auxiliary Generators, 26 August 1996”