HONEYWELL CC-TAIN01控制器模塊
減少產生干擾曲線的機會如果要求電機驅動高慣性負載,則加速時間超過安全失速時間是完全可能的,也是可以接受的(記住,鎖定轉子的情況不同于加速情況)。在這種情況下,必須知道熱極限曲線的每個不同部分,并且必須根據該曲線協調保護。保護電機的繼電器必須能夠區分轉子鎖定狀態、加速狀態和運行狀態。469電壓相關過載曲線功能專門用于保護這些類型的電機。在電機啟動期間持續監測電壓,并相應調整加速熱極限曲線。電壓相關過載曲線由失速或鎖定轉子狀態、加速度和運行過載確定的三種熱極限曲線特征形狀組成。通過輸入運行過載保護曲線的自定義曲線形狀來構建曲線。接下來,必須根據最小允許線路電壓定義的最小允許啟動電壓,在與自定義曲線相交的點處為加速度保護曲線輸入一個點。還必須輸入該電壓的鎖定轉子電流和安全失速時間。必須輸入100%線路電壓的第二個交點。再次,必須輸入鎖定轉子電流和安全失速時間,這一次是100%線路電壓。根據最小允許線路電壓和100%線路電壓之間的測量線路電壓,從安全失速時間和交叉點創建的保護曲線將是動態的。這種保護方法與阻抗繼電器一樣,固有地考慮了電機速度的變化。阻抗的變化由電機端子電壓和線路電流反映。對于任何給定的速度和任何給定的線路電壓,只有一個線路電流值。圖4-8:高慣性負載的熱極限1 123 456 78 2 3 4 5 6 7 8 9 10 20 30 40 50 60 70 80 90 100高慣性負載過載曲線8800 HP,13.2 kV,反應堆冷卻劑泵GE多線跳閘時間(秒)多個滿載安培200 300 400 500 600 700 900 1000 1 2 3 4 6 5 1-運行過載熱極限2-80%V 3時的加速熱極限-100%V 4時的加速溫度極限-鎖定轉子熱極限5-80%V 6時的電機加速曲線-100%V 806821A4.CDR g 4-36 469電機管理繼電器GE多行4.6 S5熱模型4設定值4為了說明電壓相關過載曲線特性,將使用圖4–8:高慣性負載熱極限的熱極限。1.構建運行過載熱極限的自定義曲線。如果曲線未延伸到加速熱極限,則將其延伸,使曲線與加速熱極限曲線相交(請參見下面的自定義曲線)。2.輸入加速度過載曲線與80%線路電壓的自定義曲線相交的單位電流值。同時輸入80%線路電壓的每單位電流和安全失速保護時間(見下面的加速曲線)。3.輸入加速度過載曲線與100%線路電壓的自定義曲線相交的單位電流值。同時輸入100%線路電壓的單位電流和安全失速保護時間(見下面的加速曲線)。13.2 kV,反應堆冷卻劑泵跳閘時間(秒)多個滿載安培200 300 400 500 600 700 800 900 1000加速度相交于80%V加速度相交于100%V GE Multilin 806823A4。DR GE Multilin 469電機管理繼電器4-37 4設定值4.6 S5熱模型4 469采用所提供的信息,為最小值和100%之間的任何電壓創建保護曲線。
reduce the chance of nuisance CURVE If the motor is called upon to drive a high inertia load, it is quite possible and acceptable that the acceleration time exceeds the safe stall time (bearing in mind that a locked rotor condition is different than an acceleration condition). In this instance, each distinct portion of the thermal limit curve must be known and protection must be coordinated against that curve. The relay that is protecting the motor must be able to distinguish between a locked rotor condition, an accelerating condition and a running condition. The 469 Voltage Dependent Overload Curve feature is tailored to protect these types of motors. Voltage is continually monitored during motor starting and the acceleration thermal limit curve is adjusted accordingly. The Voltage Dependent Overload Curve is comprised of the three characteristic shapes of thermal limit curves as determined by the stall or locked rotor condition, acceleration, and running overload. The curve is constructed by entering a custom curve shape for the running overload protection curve. Next, a point must be entered for the acceleration protection curve at the point of intersection with the custom curve, based on the minimum allowable starting voltage as defined by the minimum allowable line voltage. The locked rotor current and safe stall time must also be entered for that voltage. A second point of intersection must be entered for 100% line voltage. Once again, the locked rotor current and the safe stall time must be entered, this time for 100% line voltage. The protection curve created from the safe stall time and intersection point will be dynamic based on the measured line voltage between the minimum allowable line voltage and the 100% line voltage. This method of protection inherently accounts for the change in motor speed as an impedance relay would. The change in impedance is reflected by motor terminal voltage and line current. For any given speed at any given line voltage, there is only one value of line current. Figure 4–8: THERMAL LIMITS FOR HIGH INERTIAL LOAD 1 123 456 78 2 3 4 5 6 7 8 9 10 20 30 40 50 60 70 80 90 100 HIGH INERTIA LOAD OVERLOAD CURVES 8800 HP, 13.2 kV, REACTOR COOLANT PUMP GE Multilin TIME TO TRIP (SECONDS) MULTIPLES OF FULL LOAD AMPS 200 300 400 500 600 700 800 900 1000 1 2 3 4 6 5 1- Running Overload Thermal Limit 2- Acceleration Thermal Limit at 80%V 3- Acceleration Thermal Limit at 100%V 4- Locked Rotor Thermal Limit 5- Motor Acceleration Curve at 80% V 6- Motor Acceleration Curve at 100%V 806821A4.CDR g 4-36 469 Motor Management Relay GE Multilin 4.6 S5 THERMAL MODEL 4 SETPOINTS 4 To illustrate the Voltage Dependent Overload Curve feature, the thermal limits of Figure 4–8: Thermal Limits for High Inertial Load will be used. 1. Construct a custom curve for the running overload thermal limit. If the curve does not extend to the acceleration thermal limits, extend it such that the curve intersects the acceleration thermal limit curves (see the Custom Curve below). 2. Enter the per unit current value for the acceleration overload curve intersect with the custom curve for 80% line voltage. Also enter the per unit current and safe stall protection time for 80% line voltage (see the Acceleration Curve below). 3. Enter the per unit current value for the acceleration overload curve intersect with the custom curve for 100% line voltage. Also enter the per unit current and safe stall protection time for 100% line voltage (see the Acceleration Curve below). 13.2 kV, REACTOR COOLANT PUMP TIME TO TRIP (SECONDS) MULTIPLES OF FULL LOAD AMPS 200 300 400 500 600 700 800 900 1000 Acceleration intersect at 80%V Acceleration Intersect at 100%V GE Multilin 806823A4.CDR GE Multilin 469 Motor Management Relay 4-37 4 SETPOINTS 4.6 S5 THERMAL MODEL 4 The 469 takes the information provided and create protection curves for any voltage between the minimum and 100%.