- Transformer;
3. With respect to the mode of transmitting the energy, as
- a. Constant pressure;
- b. Constant current.
4. With respect to the kind of current, as
- a. Single phase { two wire;
- { three wire;
- b. Monocyclic
- { four wire;
- c. Two phase { three wire;
- { five wire;
- { six wire;
- { three wire;
- { four wire;
- d. Three phase { star connection;
- { delta connection;
- { star delta connection;
- { delta star connection;
- e. Multi-phase { of more than
- { three phases;
5. With respect to transmission and distribution, as
- a. Frequency changing;
- b. Phase changing;
- c. Converter;
- d. Rectifier.
In order to comprehend the relative advantages of the various alternating current systems, it is first necessary to understand the principle of vector summation.
Vector Summation.—This is a simple geometrical process for ascertaining the pressure at the free terminals of alternating current circuits. The following laws should be carefully noted: