LSM200 Series controls DESCRIPTION
Load Sharing Mode
Engine generator sets with isochronous governors maintain the requested speed very precisely. If synchronous generators are electrically paralleled to increase the total generated power capability, a system to apportion the load is required. Even the finest electric governors will have minor frequency differences among units to be paralleled, which would cause power varia- tions. In this case, one generator set would continuously increase the power it produces, while the other sets would decrease the power they produce. This condition eventually leads to motorizing one or more generator/ engines. The load sharing system continuously adjusts the governor speed set- tings so that no average power difference exists. The genera- tors are locked together through electrical synchronizing torques. They act as though they are tightly connected through
a gear drive.
The load sharing module measures the power that the genera- tor supplies to the main bus. Voltage inputs accept two ranges of three phase voltage. This covers most all applications (see table in the specifications). In the design of poly- phase gener- ators, the presence of a third harmonic is possible. This odd order harmonic may cause errors in load sharing systems. To minimize this error and to improve the load sharing, a terminal is provided to connect to the neutral of a Wye configuration gen- erator.