FAIL-SAFE COMMON CONTROL OF MULTIPLE ALTERNATORS CONNECTED IN TANDEM PARALLEL

摘要

Two or more ALTERNATORs - each typically of an economical cost and of any mixture of types and capacities - are turned by a single motive power source - normally the engine of a large commercial truck or bus. The several ALTERNATORs are electrically connected in tandem-parallel across a SYSTEM BATTERY and a SYSTEM LOAD. A corresponding number of electronic VOLTAGE REGULATORs, preferably themselves of a fail-state type, respectively individually control the ALTERNATORs. One electronic voltage regulator that is modified to become a designated master produces a 'universal' control signal in response to variations in a voltage across the SYSTEM BATTERY/SYSTEM LOAD. This 'universal' control signal is further used in the MASTER VOLTAGE REGULATOR itself to develop a conventional signal providing regulation to an associated ALTERNATOR. The same universal control signal is provided by wired connection to all remaining, preferably identical, VOLTAGE REGULATORs, each of which is modified to become a FOLLOWER VOLTAGE REGULATOR. Each of the FOLLOWER VOLTAGE REGULATORs produces a signal for the regulation control of its associated ALTERNATOR not by reference to the battery/load voltage (as would be normal), but rather by reference to the universal control signal. Failure malfunctions of one only ALTERNATOR, or one only VOLTAGE REGULATOR, do not cause either outage or runaway of the entire system, but instead only cause either reduced power generation capacity in the system, or runaway in one only of the ALTERNATORs. Triple alternator systems producing power to 480 amperes and more (typically at 12 v.d.c.), are routinely economically realized, and are reliably operated at reduced life cycle cost versus a single alternator-regulator system of similar capacity.