SK827005交流接触器
无功下垂补偿
DECS-100提供无功下垂补偿功能，以帮助分担无功负载在并联发电机运行期间。当该功能启用时，DECS-100计算无功使用感应到的发电机输出电压和电流量的发电机负载部分，然后相应地修改电压调节设定点。单位功率因数发电机负载导致：发电机输出电压无变化。滞后功率因数发电机负载（感应）导致发电机输出电压降低。领先功率因数发电机负载（电容性）导致发电机输出电压增加。额定、标称B相时，下垂可调高达10%线路电流（通过端子CT1和CT2施加的1安培或5安培）和0.8功率因数。这个通过并联发电机补偿触点输入电路启用和禁用下垂特性（端子52L和52M）。在var或功率因数控制模式下运行时，下垂也被禁用。
低频当发电机频率下降到所选拐点频率设定值以下时，电压设定值为由DECS-100自动调整，使发电机电压遵循选定的PU（每单位）V/Hz曲线在选定的PU V/Hz曲线上运行时，低频激活指示灯亮起前面板和BESTCOMS。低于12赫兹时禁用欠频控制。膝关节频率为以0.1赫兹增量从40赫兹到65赫兹可调，且PU V/Hz曲线的斜率可设置为0通过BESTCOMS软件在0.01步中设置为3。斜率为0将有效禁用欠频作用DECS-100的最小调节点约为标称值的30%设定点。保护DECS-100包括三种保护功能：发电机过压、传感电压损失和磁场过电压。每个保护功能都有一个相应的前面板指示灯，当功能处于活动状态。主动保护功能也通过BESTCOMS通知。
发电机过电压
发电机过电压条件可配置为（在BESTCOMS中）关闭DECS-100继电器输出、禁用DECS-100、启动两个动作或不启动任何动作。当感测到发电机在可调报警时间内，电压升高超过可调电压电平设定值DECS-100启动所选动作。
如果DECS-100配置为关闭继电器输出，发电机过电压条件将点亮前面板和BESTCOMS发电机过压指示器，并关闭端子AL1处的继电器输出和AL2。
如果DECS-100配置为硬件关机，发电机过电压条件将禁用报警时间延迟到期后的DECS-100。当发电机后DECS-100通电时过电压停机时，发电机过电压指示灯将点亮5秒钟。
电压电平设定值可在系统电压设定值的100%至120%之间调整。报警时间延迟可从0到10秒进行调整。
Reactive Droop Compensation
The DECS-100 provides a reactive droop compensation feature to assist in the sharing of reactive load
during parallel generator operation. When this feature is enabled, the DECS-100 calculates the reactive
portion of the generator load using the sensed generator output voltage and current quantities and then
modifies the voltage regulation setpoint accordingly. A unity power factor generator load results in almost
no change in generator output voltage. A lagging power factor generator load (inductive) results in a
reduction of generator output voltage. A leading power factor generator load (capacitive) results in an
increase of generator output voltage. Droop is adjustable up to 10 percent with rated, nominal B-phase
line current (1 ampere or 5 amperes applied through terminals CT1 and CT2) and 0.8 power factor. The
droop feature is enabled and disabled through the Parallel Generator Compensation contact input circuit
(terminals 52L and 52M). Droop is also disabled when operating in var or power factor control modes.
Underfrequency
When generator frequency drops below the selected knee frequency setpoint, the voltage setpoint is
automatically adjusted by the DECS-100 so that generator voltage follows the selected PU (per unit) V/Hz
curve. When operating on the selected PU V/Hz curve, the Underfrequency Active indicator lights on the
front panel and in BESTCOMS. Underfrequency control is disabled below 12 hertz. The knee frequency is
adjustable from 40 to 65 hertz in 0.1 hertz increments and the PU V/Hz curve may be set at a slope of 0
to 3 in 0.01 steps through BESTCOMS software. A slope of 0 effectively disables the underfrequency
function. The DECS-100 has a minimum regulation point of approximately 30 percent of the nominal
setpoint. Protection
The DECS-100 includes three protective functions: generator overvoltage, loss of sensing voltage, and
field overvoltage. Each protective function has a corresponding front panel indicator that lights when the
function is active. An active protective function is also annunciated through BESTCOMS.
Generator Overvoltage
A generator overvoltage condition can be configured (in BESTCOMS) to close the DECS-100 relay
output, disable the DECS-100, initiate both actions, or initiate neither action. When the sensed generator
voltage increases above the adjustable voltage level setpoint for the duration of the adjustable alarm time
delay, the DECS-100 initiates the selected action.
If the DECS-100 is configured to close the relay output, a generator overvoltage condition will light the
front panel and BESTCOMS Generator Overvoltage indicator and close the relay output at terminals AL1
and AL2.
If the DECS-100 is configured for hardware shutdown, a generator overvoltage condition will disable the
DECS-100 after the alarm time delay expires. When the DECS-100 is powered up following a generator
overvoltage shutdown, the Generator Overvoltage indicator will light for five seconds.
The voltage level setpoint is adjustable from 100 to 120 % of the system voltage setting. The alarm time
delay is adjustable from 0 to 10 seconds.
