SAI918 digital measurement and control protection device set value list

Transverse differential protection

1) the action current: the maximum unbalance current setting of the normal operation of the generator;

2) action delay: in general, the instantaneous action, when the rotor one point after the 0.5~1S of the whole set time delay action.

Two, loss of magnetic protection

1) impedance circle: general generator static stability circle tuning, can also according to the asynchronous setting circle;

2) impedance circle radius: in general, the static stability of the generator is fixed, but also can be adjusted according to the asynchronous circle;

3) system low voltage: low voltage setting as long as the system is allowed to operate;

4) rotor low voltage: in accordance with the generator no-load excitation voltage of 0.2~0.5 times the whole set;

5) rotor low voltage criterion coefficient, the coefficient for tuning rotor voltage and active action to the slope of the curve, D Kf=KK/X sigma, the XD Sigma =Xd + XS is, XD electric resistance standard unitary value, XS is the value of the reactance of the transformer and system and standard unitary, KK reliable coefficient;

6) reaction power: consider the salient pole effect Pt=1/2 * Sn * (1/Xq Sigma - 1/Xd sigma), the XD Sigma =Xd + XS, XQ Sigma =Xq + XS and XD generator d-axis reactance standard unitary value and XQ generator q-axis reactance p.u., Sn for secondary reference power.

7) action delay 1: the general setting for the loss of magnetic after the alarm or switch excitation delay time;

8) action delay 2: the general setting for the loss of magnetic trip time;

9) action delay 3: the general setting for the system after the loss of magnetic system voltage is less than the allowable value of the trip time.

Three, composite voltage over current protection

1) over current action value: according to and the adjacent reserve protection with the whole set, and is greater than the generator's rated current;

2) low voltage operating value: the minimum voltage setting that may occur in the operation of the generator;

3 negative sequence voltage action value: in accordance with the normal operation of the maximum unbalanced voltage setting;

4, 1 and 2 of the action time: in accordance with the coordination and the adjacent reserve;

5) current memory time: according to the actual situation of the system.