GE IC800SSI228RD2-CE自動(dòng)化模塊
大多數(shù)系統(tǒng)在滿載時(shí)使用6.0 Vdc的負(fù)載增益電壓。到在低于滿載的情況下執(zhí)行此步驟，使用負(fù)載增益與所用負(fù)載百分比成比例的電壓值。對(duì)于例如，如果滿載時(shí)的負(fù)載增益電壓為6.0 Vdc，則在50%負(fù)載下，調(diào)整負(fù)載增益電壓為3.0 Vdc。
操作說明介紹
這些2301A型號(hào)的速度和負(fù)荷分擔(dān)部分監(jiān)控和控制兩個(gè)功能。
?速度：速度控制部分將原動(dòng)機(jī)保持在正確的位置速度
?兩臺(tái)或多臺(tái)發(fā)電機(jī)并聯(lián)運(yùn)行期間的負(fù)荷分配，以及負(fù)載分擔(dān)部分感測(cè)其發(fā)電機(jī)承載的負(fù)載，并導(dǎo)致系統(tǒng)中所有發(fā)電機(jī)的負(fù)荷按比例分配。
速度控制
圖4-1所示的速度控制系統(tǒng)包括：
?感應(yīng)原動(dòng)機(jī)速度的裝置（1）
?頻率-電壓轉(zhuǎn)換器（2）
?可與原動(dòng)機(jī)速度進(jìn)行比較的速度基準(zhǔn)（3）
?速度加法器/放大器（4），其輸出與在任何給定負(fù)載下保持所需速度所需的燃料或蒸汽
?致動(dòng)器（5），用于定位原動(dòng)機(jī)的燃料或蒸汽機(jī)構(gòu)速度感測(cè)裝置（如磁性拾取器）感測(cè)并將其轉(zhuǎn)換為頻率與原動(dòng)機(jī)速度。
頻率-電壓轉(zhuǎn)換器接收來自轉(zhuǎn)速傳感器的交流信號(hào)并將其改變成比例直流電壓。
速度參考電路產(chǎn)生直流“參考”電壓，與速度信號(hào)電壓進(jìn)行比較。參見伍德沃德手冊(cè)82510，磁性拾取器&
電子控制的接近開關(guān)，有關(guān)磁性的更多信息皮卡。
在求和時(shí)，將速度信號(hào)電壓與參考電壓進(jìn)行比較指向如果速度信號(hào)電壓低于或高于參考電壓，則信號(hào)由控制放大器發(fā)送，要求增加或減少速度執(zhí)行器通過重新定位來響應(yīng)來自控制放大器的信號(hào)燃料或蒸汽架，改變?cè)瓌?dòng)機(jī)的速度，直到速度信號(hào)電壓和參考電壓相等。
故障轉(zhuǎn)速信號(hào)電路監(jiān)控轉(zhuǎn)速信號(hào)輸入。當(dāng)沒有信號(hào)時(shí)檢測(cè)到，需要最低燃油。最小燃油信號(hào)足以導(dǎo)致：如果不受限制，執(zhí)行器將轉(zhuǎn)到最小位置。然而，由于外部系統(tǒng)中的連桿調(diào)整或其他限制，最小執(zhí)行機(jī)構(gòu)
該位置可能不允許原動(dòng)機(jī)停機(jī)。
*—Most systems use a Load Gain Voltage of 6.0 Vdc at full load. To
perform this procedure at less than full load, use a Load Gain
Voltage value that is proportional to the percent load used. For
example, if the Load Gain Voltage at full load is 6.0 Vdc, you would
adjust for a Load Gain Voltage of 3.0 Vdc at 50% load.
Chapter 4.
Description of Operation
Introduction
The speed and load sharing section of these 2301A models monitors and
controls two functions.
? Speed—The speed control section keeps the prime mover at the correct
speed.
? Load Sharing—During parallel operation of two or more generators, the
load sharing section senses the load carried by its generator and causes the
loads of all generators in the system to be shared proportionally.
Speed Control
The Speed Control system as shown in Figure 4-1 consists of:
? a device (1) to sense the speed of the prime mover
? a Frequency to Voltage Converter (2)
? a Speed Reference (3) to which the prime mover speed can be compared
? A Speed Summer/Amplifier (4) with an output proportional to the amount of
fuel or steam required to maintain the desired speed at any given load
? An Actuator (5) to position the fuel or steam mechanism of the prime mover
A speed-sensing device, such as a magnetic pickup, senses the speed of the
prime mover, and converts it to an ac signal with a frequency proportional to
prime-mover speed.
The frequency-to-voltage converter receives the ac signal from the speed sensor
and changes it to a proportional dc voltage.
A speed-reference circuit generates a dc “reference” voltage to which the speedsignal voltage is compared. See Woodward manual 82510, Magnetic Pickups &
Proximity Switches for Electronic Controls, for more information on magnetic
pickups.
The speed-signal voltage is compared to the reference voltage at the summing
point. If the speed-signal voltage is lower or higher than the reference voltage, a
signal is sent by the control amplifier calling for an increase or decrease in
speed.
The actuator responds to the signal from the control amplifier by repositioning the
fuel or steam rack, changing the speed of the prime mover until the speed-signal
voltage and the reference voltage are equal.
A failed-speed-signal circuit monitors the speed-signal input. When no signal is
detected, it calls for minimum fuel. The minimum-fuel signal is sufficient to cause
the actuator to go to the minimum position if not restricted. However, due to
linkage adjustment or other restrictions in the external system, minimum actuator
position may not permit prime-mover shutdown.
