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.
The ESD5500E Series speed control unit is an all electronic device designed to control engine speed with fast and precise response to transient load changes. This closed loop control, when connected to a proportional electric actuator and sup-plied with a magnetic speed sensor signal, will control a wide variety of engines in an isochronous or droop mode. It is designed for high reliability and built ruggedly to withstand the engine environment. Simplicity of installation and adjustment was foremost in the design. Non-interacting performance controls allow near optimum response to be easily obtained. The primary features of the ESD5500E Series speed control unit are the engine STARTING FUEL and SPEED RAMPING adjustments. The use of these features will minimize engine exhaust smoke experienced prior to attaining engine operating speed. Other features include adjustable droop and idle operation, inputs for accessories used in multi-engine or special applica-tions, protection against reverse battery voltage, transient voltages, accidental short circuit of the actuator and fail safe design in the event of loss of speed sensor signal or battery supply. The ESD5500E Series speed control unit is compatible with all GAC proportional actuators except the ACB2000 electric actuator. When the ESD5500E Series speed control unit is used with a ADC100 Series electric actuator, the DROOP adjustment range will be less due to this actuator's low current demand.
