Parallel generator power system

#This invention relates to the field of power generation, and more specifically to a system for choosing between two or more electrical generators when starting a parallel generator power system.

#Electrical generators or generator sets are devices which transform mechanical energy into electrical energy. A typical generator set includes an engine, driven by a fuel such as gasoline, and a rotating shaft driven by the engine. The rotating shaft develops electric power, which is then used to power an electrical load.

#Sometimes, two or more generator sets are connected to a common bus in a parallel arrangement. This allows for each of the generator sets to be turned on as needed. For instance, if a light load is being fed, then only one generator set may be needed. As the load increases, a second generator set, a third generator set, and so on can be activated.

#FIG. 1 shows a block diagram of a parallel generator set power system according to one embodiment.

#FIG. 2 shows details of the power system of FIG. 1.

#FIG. 3 shows a schematic diagram of electronics and hardware of a starting module of the present system.

#In the following detailed description, reference is made to the accompanying drawings which form a part hereof, and in which is shown by way of illustration specific embodiments in which the invention may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention, and it is to be understood that other embodiments may be utilized and that structural changes may be made without departing from the scope of the present invention. Therefore, the following detailed description is not to be taken in a limiting sense, and the scope of the present invention is defined by the appended claims and their equivalents.

#FIG. 1 shows a schematic representation of a power system 100 which includes two or more engine-generator sets 102 connected in parallel to a common bus 110. In this example, generator sets 1 and 2 are shown. The present system is applicable to almost any number of generator sets. In one embodiment, there can be between two and twenty-four generator sets connected together in parallel. Generator sets 102 feed a load 130 via bus 110. A switch 104, such as a circuit breaker, is located between each generator 102 and bus 110. When a given switch 104 is closed, the associated generator set 102 is connected to bus 110 and feeds the load. A start control 105 is connected to each generator set to control the start up of the generator sets.

#In one embodiment, each of generator sets 102 are diesel or gas generator sets manufactured by Cummins Power Generation, Inc. In one example use, the system is applicable to diesel generator sets in the 30 Kw to 2 Mw range equipped with hardware which is capable of automatic isolated bus paralleling.