REACTOR MEGAWATT DEMAND SETTER

• US 3,849,637 A
• Filed: 05/22/1973
• Issued: 11/19/1974
• Est. Priority Date: 05/22/1973
• Status: Expired due to Term

• Current Assignee: Musick Jr Charles, Robert M. Caruso
• Original Assignee: Musick Jr Charles, Robert M. Caruso
• Inventors: Caruso, Robert M., Musick, Charles R.
• Primary Examiner(s): Morrison, Malcolm A.
• Assistant Examiner(s): Wise, Edward J.
• Application Number:
  US05/362,786
• Time in Patent Office: 546 Days
• Field of Search: 235/151,151.21,184,185 176/2R,60 307/52,57,60
• US Class Current: 700/287
• CPC Class Codes: G21D 3/00 Control of nuclear power plant control of nuclear reaction in general G21C7/00
• CPC Class Codes: Y02E 30/00 Energy generation of nuclear origin
• CPC Class Codes: Y02E 30/30 Nuclear fission reactors

Abstract

The electrical power output of a nuclear powered generating station, as requested by an operator or by an automatic dispatch system for the grid with which the station is associated, is controlled in a manner which insures that the nuclear steam supply system limits are not violated. The invention permits the nuclear powered generating unit to operate at maximum permissible power for the existing nuclear steam supply system conditions by exercising control over the unit turbine in such a manner that the rate of load change will be controlled as a function of the proximity of the actual load to the desired load and the rate of load increase will be algebraically limited by the proximity of the nuclear steam supply system conditions to the steam supply system operating limits. Additionally the turbine load will automatically be reduced when necessary at a rate which equals or exceeds a value which is commensurate with the magnitude of any violation of the steam supply system operating limits.

Claims

1. An improved method for controlling the load on an electrical power generation unit, the generation unit including a nuclear steam supply system and a steam turbine driving a generator, the method including the steps of:

comparing the desired unit load with actual load to provide a unit load error indication;

controlling the turbine in accordance with the unit load error indication to null the load error by adjusting the turbine load;

monitoring a plurality of nuclear steam supply system operating conditions;

comparing the monitored steam supply system conditions with their permissible limits and providing signals commensurate with differences therebetween;

providing a load change rate override command whenever the margin between any of the monitored steam supply system operating conditions and its limit is within a preselected range; and

adjusting the load on the turbine at a rate commensurate with any override command.

2. The method of claim 1 wherein the step of monitoring nuclear steam supply system operating conditions comprises:

receiving signals commensurate with a plurality of nuclear steam supply system operating parameters which respond to a decrease in turbine load to increase the margin between the parameter and its limit.

3. The method of claim 2 wherein the step of providinG a load change rate override command includes:

generating a load decrease rate override command whenever any of the monitored steam supply system operating conditions exceeds its limit.

4. The method of claim 2 wherein the step of providing a load change rate override command includes:

generating a load increase rate override signal whenever any of the monitored conditions approaches within a preselected margin of but does not exceed its limit.

5. The method of claim 3 wherein the step of providing a load change rate override command further includes:

generating a load increase rate override signal whenever any of the monitored conditions approaches within a preselected margin of but does not exceed its limit.

6. The method of claim 5 wherein the step of adjusting the load on the turbine at a rate commensurate with any override command comprises:

reducing the load on the turbine at a rate commensurate with the magnitude of the largest of any existing limit excess; and

reducing the rate of load increase pursuant to nulling a unit load error in accordance with any load increase rate override signal to decrease the permitted rate of load increase as margins between the monitored operating conditions and their limits are consumed.

7. The method of claim 2 wherein the step of controlling the turbine comprises:

establishing a maximum load increase rate;

establishing a maximum load decrease rate;

establishing a variable load change rate between the maximum increase and decrease rates, the variable rate being proportional to load error;

selecting a load change rate commensurate with the magnitude of the load error whereby the load may be varied at either of the maximum rates or at a variable rate which decreases with the load error; and

employing the selected load rate to adjust the turbine load.

8. The method of claim 6 wherein the step of generating a load decrease rate override command comprises:

providing a first signal commensurate with the margin between a first nuclear steam supply system limiting condition and its limit;

providing at least a second signal commensurate with the margin between a second nuclear steam supply system operating condition and its limit;

selecting the one of said first and second signals commensurate with the greater of any condition limit violation;

comparing the selected one of the first and second signals with any existing unit load error; and

selecting for turbine load control the greater load decrease rate as established by either the selected of the first and second signals or by the unit load error.

9. The method of claim 6 wherein the step of generating a load increase rate override command comprises:

providing a first signal commensurate with the margin between a first nuclear steam supply system limiting condition and its limit whenever the condition approaches within a predetermined proximity to its limit;

providing at least a second signal commensurate with the margin between a second nuclear steam supply system operating condition and its limit whenever the condition approaches within a predetermined proximity to its limit;

selecting the one of said first and second signals commensurate with the lesser of the margins remaining;

comparing the selected one of the first and second signals with any existing unit load error; and

selecting for turbine load control the lesser load increase rate as established by either the selected of the first and second signals or by the unit load error.

10. The method of claim 8 wherein the step of generating a load increase rate override command comprises:

providing a third signal commensurate with the margin between a first nuclear steam supply system limiting condition and its limit whenever the condition approaches within a predetermined proximity to its limit;

providing at least a fourth signal commensurate with the margin between a second nuclear steam supply system operatIng condition and its limit whenever the condition approaches within a predetermined proximity to its limit;

selecting the one of said third and fourth signals commensurate with the lesser of the margins remaining;

comparing the selected one of the third and fourth signals with any existing unit load error; and

selecting for turbine load control the lesser load increase rate as established by either the selected of the third and fourth signals or by the unit load error.