Woodward -5/P2 8440-1857 Genset Control

The Power Factor Characteristic function is adapting the reactive

power flow between generator and mains to support a dynamic

stabilization of the mains. Some network provider prefer therefore

a power factor control over real power PF(P) (see chapter

Ä Chapter 4.5.12.6.2.1 “Power factor characteristic PF(P) ”

on page 279 for more details).

Power factor characteristic PF(P)

A method to support the mains is to feed different reactive power

values into the grid in relation to the own active power value. The

reactive power is defined through a power factor setpoint for the

generator. This can be defined in characteristic curve

The linear characteristic is defined by two points (① & ②). The

power factor corresponding to this characteristic is available as

data source 05.29 in the Analog Manager

The easYgen performs proportional load and/or var sharing. This

means each generator will share the load at the same percentage

level of the generator rated power when paralleled against the

mains, in an isolated operation with multiple generators paralleled,

or when re-synchronizing the common bus to the mains

Mains Parallel Operation With Mains Interchange Real Power Control (Import/Export)

The easYgen controllers maintain the real load level on the individ

ually controlled generators at a level so that the real power setpoint

at the mains interchange remains at the configured setpoint. The

real power setpoint for the mains interchange must be configured

identically for each easYgen

system via a CAN bus. This enables the controllers to adjust the

real power generated by the generator while remaining within the

rated power of the generator. A smaller generator will contribute

less real power as compared to a large generator, but they will

both be utilized to the same capacity factor. An example of this

would be a 100 kW generator with a configured 1000 kW generator

and a mains interchange of 825 kW. The 100 kW generator would

contribute 75 kW and the 1000 kW generator would contribute

750 kW or both generators would be at 75 % of their rated

capacity.

How the reactive power handling is executed depends the PF/kvar

setpoint mode. Two setpoints (5743 Ä p. 278 and 5744 Ä p. 278)

are available. Each setpoint allows the modes:

n Gen PF

n Mains PF

n Mains Import kvar

n Mains export kvar

In PF modes the reactive load sharing is not performed when

operating in parallel with the mains. Reactive power control will be

defined by the configured power factor setpoints (5620 Ä p. 278 or

5621 Ä p. 278) of the individual controllers. If the power factor con

troller setpoint is configured as +0.950. the easYgen will propor

tionally share the real load with all generators in parallel with the

mains while controlling the reactive power at a 0.95 inductive (lag

ging) power factor regardless of the what power factor the mains is

operating at.

The parameter “Active power Load share factor” (param

eter 5530 Ä p. 285) can be used now to define the priority of the

real power sharing reference variable (real power at interchange).

A higher configured percentage influences the control more

towards maintaining the real power setpoint for the interchange. A

lower configured percentage influences the control more towards

maintaining real power sharing between units.

In kvar modes the reactive load sharing is performed when oper

ating in parallel with the mains. Mains import/export kvar control at

the interchange point will be determined by the configured int. kvar

setpoints (5745 Ä p. 278 or 5746 Ä p. 278) of the individual con

trollers.

Isolated Operation In Parallel

The easYgen controllers maintain the voltage and frequency of the

individually controlled generators at a constant level. This makes it

imperative that the voltage and frequency setpoints are configured

identically for each easYgen