GE DFP14C1N000GB控制模塊
如果滿載時(shí)為6伏(或與負(fù)載成比例的較低電壓小于無法獲得100%),并且已檢查相位,并且正確,電流互感器可能尺寸錯(cuò)誤。滿負(fù)荷時(shí),電流互感器輸出必須為3至7A(標(biāo)稱5A)。
可能需要降低系統(tǒng)中每個(gè)單元的負(fù)載信號電壓在極差的系統(tǒng)動力學(xué)的情況下低至3V。如果您的系統(tǒng)
需要低至3 V的負(fù)載信號電壓,請咨詢伍德沃德以獲取建議
尋找可能的補(bǔ)救辦法。下垂調(diào)整當(dāng)發(fā)電機(jī)組處于以下狀態(tài)時(shí),有必要調(diào)整下垂電位計(jì):
以在下垂模式下操作。負(fù)載傳感器的下降通常表示為:作為百分比,并通過以下公式計(jì)算。
%下垂=空載速度-滿載速度
空載速度x100設(shè)置下垂的方法取決于發(fā)電機(jī)組的負(fù)載是否:隔離負(fù)載或無限總線。
設(shè)置隔離負(fù)載的降速
1.斷開連接至端子14的下垂觸點(diǎn)。
2.啟動原動機(jī)并調(diào)整額定轉(zhuǎn)速電位計(jì)空載時(shí)的額定轉(zhuǎn)速。
3.施加全負(fù)荷*
4.調(diào)整下垂電位計(jì)以獲得所需速度。
例如:在60 Hz下運(yùn)行,在滿載下57 Hz表示5%的下降。
*-如果只有50%的負(fù)載是可能的,58.5 Hz將表示5%的下降(見圖3-3).
針對公用設(shè)施設(shè)置下垂使用以下步驟設(shè)置下垂和負(fù)載增益電位計(jì):公用事業(yè)作為唯一的負(fù)載。
1.在以下情況下計(jì)算發(fā)電機(jī)的滿載速度(或頻率):以100%負(fù)載運(yùn)行。
空載頻率=額定頻率x(1+下降%)
示例:額定頻率=60.0 Hz
所需下垂=3%(0.03)
空載頻率=60 x(1+0.03)=61.8 2。以步驟1中計(jì)算的速度空載運(yùn)行發(fā)電機(jī)。記錄速度設(shè)置設(shè)備的設(shè)置:
?帶有鉛筆標(biāo)記的電位計(jì)記錄設(shè)置。
?MOP或其他測量并記錄速度設(shè)置值電壓(控制處)。
3.將系統(tǒng)速度降低到額定(頻率)。
4.完全順時(shí)針預(yù)設(shè)負(fù)載增益和下降電位計(jì)(be小心不要過度扭轉(zhuǎn)鍋)。
如果在閉合斷路器時(shí),裝置上的負(fù)載迅速增加,打開斷路器并關(guān)閉機(jī)組。檢查CTs和PTs。允許機(jī)組繼續(xù)裝載,或在不糾正此情況的情況下繼續(xù)操作系統(tǒng)可能導(dǎo)致設(shè)備損壞,人員受傷或死亡。
5.同步、閉合發(fā)電機(jī)斷路器,并通過將速度設(shè)置增加到步驟2中記錄的設(shè)置。
步驟6和7中的調(diào)整是非線性的。更改小增量以防止過載。
6.通過轉(zhuǎn)動下垂電位計(jì)增加裝置上的負(fù)載逆時(shí)針旋轉(zhuǎn),直到負(fù)載增益電壓讀數(shù)為6.0 Vdc*。
7.通過逆時(shí)針轉(zhuǎn)動負(fù)載增益電位計(jì)增加負(fù)載,直到負(fù)載處于所需的100%值。
f 6 volts at full load (or a lower voltage proportional to a load less than
100%) cannot be obtained, and the phasing has been checked and is
correct, the current transformers are probably the wrong size. The currenttransformer output must be from 3 to 7 A (5 A nominal) at full load.
It may be necessary to reduce the load-signal voltage of each unit in the system
to as low as 3 V in cases of extremely poor system dynamics. If your system
requires a load-signal voltage as low as 3 V, consult Woodward for suggestions
for possible remedies. Droop Adjustment
Adjustment of the DROOP potentiometer is necessary when the generator set is
to be operated in the droop mode. Droop in a load sensor is usually expressed
as a percentage and calculated by the following formula.
% Droop =
No Load Speed – Full Load
Speed
No Load Speed
x 100
The method of setting droop depends on whether the load of the generator set is
an isolated load or an infinite bus.
Setting Droop for an Isolated Load
1. Open the droop contact connected to terminal 14.
2. Start the prime mover and adjust the RATED SPEED potentiometer for
rated speed with no load.
3. Apply full load. *
4. Adjust the DROOP potentiometer to give the desired speed.
Example: Operating at 60 Hz, 57 Hz at full load indicates 5% droop.
*—If only 50% loading is possible, 58.5 Hz would indicate 5% droop (see Figure
3-3).
Setting Droop when Against Utility
Use the following procedure to set the Droop and Load Gain potentiometers with
the utility as the only load.
1. Calculate the fully loaded speed (or frequency) of the generator when
running at 100% load.
No Load frequency = rated frequency x (1 + droop %)
Example: Rated frequency = 60.0 Hz
Desired droop = 3% (0.03)
No Load Frequency = 60 x (1 + 0.03) = 61.8 2. Run the generator at the speed calculated in step 1, with no load. Record
the setting of your speed-setting device:
? Potentiometer—record setting with a pencil mark.
? MOP or Other—measure and record the value of the speed-setting
voltage (at the control).
3. Reduce system speed to rated (frequency).
4. Preset both the Load Gain and Droop potentiometers fully clockwise (be
careful not to overtorque the pot).
If when you close the breaker, the load on the unit increases rapidly,
open the breaker and shut the unit down. Check the phasing of the
CTs and PTs. Permitting the unit to continue to pick up load or
continuing to operate the system without correcting this condition
may cause damage to equipment, and injury or death to personnel.
5. Synchronize, close the generator breaker, and increase the load by
increasing the speed setting to the setting recorded in step 2.
The adjustments in steps 6 and 7 are non-linear. Make changes in
small increments to prevent overload.
6. Increase the load on the unit by turning the Droop potentiometer
counterclockwise until the Load Gain Voltage reads 6.0 Vdc *.
7. Increase load by turning the Load Gain potentiometer counterclockwise until
the load is at the desired 100% value.