The primary purpose of the controller is always frequency control, because frequency is variable in a load
sharing system and so is the power on the individual generator. Since the load sharing system requires power
regulation as well, the controller can be affected by the power regulator. For this purpose a so-called weight
factor is used (P weight).
The regulation deviation from the power regulator can therefore have great or less influence on the controller.
An adjustment of 0 % means that the power control is switched off. An adjustment of 100 % means that the
power regulation is not limited by the weight factor. Any adjustment in between is possible.
The difference between adjusting the weight value to a high or low value is the speed at which the power
regulation deviation is eliminated. So if a firm load sharing is needed, the weight factor must be adjusted to a
higher value than if an easy load sharing is required.
An expected disadvantage of a high weight factor is that when a frequency deviation and a power deviation
exist, then hunting might occur. The solution to this is to decrease either the weight factor or the parameters
of the frequency regulator.
4.14 Power limit set point
4.14.1 Four-stage power limit set point
This function is a way of giving external commands to the ML-2 unit for max. allowable produced power by
digital inputs. The parameters are 10420 to 10423, and they are only accessible from the PC utility software.
Four set points are available. The set points indicate the maximum amount of power the ML-2 unit is allowed
to produce from 0 to 100 %. Default set points are: value 1 = 0 %, value 2 = 30 %, value 3 = 60 % and value
4 = 100 %. These set points are configurable by the PC utility software.
Example: If set point 1 is set to 30 % and active, the ML-2 unit will produce max. 30 % of nominal power. If,
for example, set points 1 and 3 are active at the same time, set point 1 will be used. Even if set point 1 is set
to 60 % and set point 3 is set to 30 %, set point 1 will still be used.
The set points are activated by a digital input and are configured by M-Logic.
4.15 M-Logic
The M-Logic functionality is included in the unit and is not an option-dependent function; however, selecting
additional I/O options can increase the functionality.
GPC-3 DRH 4189340587 UK
Additional functions
DEIF A/S Page 70 of 122
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