Control method based on primary frequency modulation priority action AGC reverse interlocking

Abstract

This invention discloses a control method based on primary frequency regulation priority action AGC reverse interlocking, which relates to the field of generator set primary frequency regulation control technology. This invention realizes primary frequency regulation priority action by short-time interlocking AGC command, thereby ensuring the speed and accuracy of primary frequency regulation action, and fully improving the output response index and power contribution index after primary frequency regulation action.

Description

Technical Field

[0001] This invention relates to the field of primary frequency regulation control technology for generator sets, and in particular to a control method based on primary frequency regulation priority action AGC reverse interlocking. Background Technology

[0002] When a generating unit engages primary frequency regulation and AGC functions, situations often arise where the load change direction of the AGC command is inconsistent with the load change direction required by the primary frequency regulation. In such cases, according to the relevant requirements of the power grid dispatching regulations (two detailed rules) and to improve the output response index and power contribution index after the primary frequency regulation action, the control requirements of the primary frequency regulation should be prioritized, the AGC command should be blocked, and the correctness of the command direction should be ensured. Summary of the Invention

[0003] The purpose of this invention is to overcome the shortcomings of existing technologies and provide a control method based on primary frequency modulation priority action AGC reverse interlocking.

[0004] This invention is achieved through the following technical solution:

[0005] A control method based on primary frequency modulation priority action AGC reverse interlocking specifically includes the following steps:

[0006] Step 1: Use the SR trigger to determine the primary frequency regulation priority action AGC reverse interlock increase / decrease signal judgment and triggering: turbine actual speed R 实 Subtract the rated speed R 额 The difference is greater than +2 r / min, the primary frequency regulation on the DEH side is activated, and the reverse blocking function is activated. All three paths are ANDed together and simultaneously meet the trigger conditions of the SR trigger SET (activation) from the point where the subsequent trigger is 1 to the reverse blocking increase; the actual turbine speed R 实 Subtract the rated speed R 额 The difference is less than -2r / min, the primary frequency regulation on the DEH side is activated, and the reverse blocking function is activated. The three paths are ANDed together and simultaneously meet the trigger conditions of the SR trigger SET (activation) from the reverse blocking to the 1st trigger.

[0007] Step 2: Actual turbine speed R 实 Subtract the rated speed R 额 If the difference is greater than +2 r / min, a 31-second pulse is emitted after a 30-second delay, and the output logic is either the actual turbine speed R. 实 Subtract the rated speed R 额 The difference is greater than +2 r / min, triggering a 30s delay before outputting the SR trigger as a reverse latch-up trigger. RESET trigger condition 1; actual turbine speed R 实 Subtract the rated speed R 额The absolute value of the difference is less than 1.9 r / min, triggering condition 2 for the SR trigger to increase the reverse blocking; condition 3 for the SR trigger to increase the reverse blocking function exits; condition 4 for the SR trigger to increase the reverse blocking function activates; and condition 5 for the SR trigger to increase the reverse blocking function activates. These four conditions are then ORed together and used as the SR trigger to increase the reverse blocking function. The reverse blocking function decreases in the same way.

[0008] As described in Step 1: After the reverse interlocking condition is activated, it is output to the unit's main control AGC target instruction processing logic as the trigger condition for the load change rate T switching function block. When the trigger condition of the load change rate T switching function block is 1, the Y loop output is selected. At this time, the load increase rate is 0. If the unit is in the load increase stage at this time, the AGC instruction will remain unchanged after the unit is limited because the load increase rate is 0. When the trigger condition of the load change rate T switching function block is 0, the N loop output is selected. At this time, the load increase rate is the value set by the operator. After the unit is limited, the AGC instruction changes according to the load increase rate and follows the AGC target instruction.

[0009] After the reverse interlocking reduction condition is activated, it is output to the unit's main control AGC target instruction processing logic as the trigger condition for the load change rate T switching function block. When the trigger condition of the load change rate T switching function block is 1, the Y loop output is selected. At this time, the load reduction rate is 0. If the unit is in the load reduction stage at this time, the AGC instruction will remain unchanged after the unit is limited because the load reduction rate is 0. When the trigger condition of the load change rate T switching function block is 0, the N loop output is selected. At this time, the load reduction rate is the value set by the operator. After the unit is limited, the AGC instruction changes according to the load increase rate and follows the AGC target instruction.

[0010] The lockout action reset condition pulse signal in step two is a pulse signal that is "1" for 30 seconds. The unit's participation in primary frequency regulation stabilization time should be less than 60 seconds. If the primary frequency regulation fails to meet all relevant technical indicators within 60 seconds, the power grid will conduct a primary frequency regulation test on the generator unit. Taking into account the actual primary frequency regulation performance of the generator unit and the AGC test standard, the reverse lockout action time is determined to be 30 seconds.

[0011] The rated speed R 额 The speed is 3000 r / min.

[0012] The advantages of this invention are: this invention achieves a first frequency modulation priority action by using a short-time lockout AGC command, thereby ensuring the speed and accuracy of the first frequency modulation action and fully improving the output response index and power contribution index after the first frequency modulation action. Attached Figure Description

[0013] Figure 1This is the SAMA logic diagram for the control method based on primary frequency modulation priority action AGC reverse interlocking described in this invention. Detailed Implementation

[0014] The control method based on primary frequency modulation priority action AGC reverse interlocking described in the present invention will be described in detail below with reference to the accompanying drawings and through embodiments:

[0015] like Figure 1 As shown in Example 1: Step 1: Use the SR trigger to determine the primary frequency regulation priority action AGC reverse interlock increase / decrease signal judgment and trigger: turbine actual speed R 实 Subtract the rated speed R 额 The difference is greater than +2 r / min, the primary frequency regulation on the DEH side is activated, and the reverse blocking function is activated. All three paths are ANDed together and simultaneously meet the trigger conditions of the SR trigger SET (activation) from the point where the subsequent trigger is 1 to the reverse blocking increase; the actual turbine speed R 实 Subtract the rated speed R 额 The difference is less than -2r / min, the primary frequency regulation on the DEH side is activated, and the reverse blocking function is activated. The three paths are ANDed together and simultaneously meet the trigger conditions of the SR trigger SET (activation) from the reverse blocking to the 1st trigger.

[0016] Step 2: Actual turbine speed R 实 Subtract the rated speed R 额 If the difference is greater than +2 r / min, a 31-second pulse is emitted after a 30-second delay, and the output logic is either the actual turbine speed R. 实 Subtract the rated speed R 额 The difference is greater than +2 r / min, triggering a 30s delay before outputting the SR trigger as a reverse latch-up trigger. RESET trigger condition 1; actual turbine speed R 实 Subtract the rated speed R 额 The absolute value of the difference is less than 1.9 r / min, triggering condition 2 for the SR trigger to increase the reverse blocking; condition 3 for the SR trigger to increase the reverse blocking function exits; condition 4 for the SR trigger to increase the reverse blocking function activates; and condition 5 for the SR trigger to increase the reverse blocking function activates. These four conditions are then ORed together and used as the SR trigger to increase the reverse blocking function. The reverse blocking function decreases in the same way.

[0017] After the reverse interlocking condition is activated, it is output to the unit's main control AGC target instruction processing logic as the trigger condition for the load change rate T switching function block. When the trigger condition of the load change rate T switching function block is 1, the Y loop output is selected. At this time, the load increase rate is 0. If the unit is in the load increase stage at this time, the AGC instruction will remain unchanged after the unit is limited because the load increase rate is 0. When the trigger condition of the load change rate T switching function block is 0, the N loop output is selected. At this time, the load increase rate is the value set by the operator. After the unit is limited, the AGC instruction changes according to the load increase rate and follows the AGC target instruction.

[0018] After the reverse interlocking reduction condition is activated, it is output to the unit's main control AGC target instruction processing logic as the trigger condition for the load change rate T switching function block. When the trigger condition of the load change rate T switching function block is 1, the Y loop output is selected. At this time, the load reduction rate is 0. If the unit is in the load reduction stage at this time, the AGC instruction will remain unchanged after the unit is limited because the load reduction rate is 0. When the trigger condition of the load change rate T switching function block is 0, the N loop output is selected. At this time, the load reduction rate is the value set by the operator. After the unit is limited, the AGC instruction changes according to the load increase rate and follows the AGC target instruction.

[0019] Example 2: Based on Example 1, when the actual turbine speed is 3005 r / min and the primary frequency regulation function and reverse interlock function are engaged, a difference calculation is performed between this and the rated speed of 3000 r / min, resulting in an output of +5 r / min, which is greater than +2 r / min. At this time, the SR trigger SET (activation) of the reverse interlock is set to 1, and the reverse interlock increase activation is set to 1. When the AGC command on the grid side of the unit increases from 250MW to 290MW, and the load increase rate is set to 2MW / min, the reverse interlock increase activation triggers the load change rate T switching function block in the unit's main control AGC target command processing logic. The output of the load change rate T switching function block changes from 2MW / min in the N loop to 0MW / min in the Y loop, thus keeping the AGC load command unchanged. Simultaneously, the actual turbine speed R... 实 Subtract the rated speed R 额 If the difference is greater than +2 r / min, a 31-second pulse is emitted after a 30-second delay, and the output logic is either the actual turbine speed R. 实 Subtract the rated speed R 额 If the difference is greater than +2 r / min, the trigger delay is 30 seconds. After the reverse interlock is triggered, it will only operate for a maximum of 30 seconds. During this period, if the speed drops from 3005 r / min to 3001.5 r / min, the actual turbine speed R 实 Subtract the rated speed R 额If the absolute value of the difference is less than 1.9 r / min, the RESET trigger condition 4 of the reverse blocking increase SR trigger will be activated to 1. At this time, the reverse blocking increase will be reset to 0, and the output of the load change rate T switching function block will change from 0 MW / min in the Y circuit to 2 MW / min in the N circuit. Then the AGC load command will resume normal tracking.

Claims

1. A control method based on the primary frequency modulation priority action AGC reverse lock, characterized in that: Specifically comprising the following steps: Step one: using SR trigger to judge the one frequency modulation priority action AGC reverse lock increase signal judgment and trigger: the actual speed R of steam turbine 实 Subtract the difference of rated speed R 额 Greater than +2r / min, DEH side one frequency modulation input, three ways through AND phase and meet the reverse lock function input at the same time trigger 1 to the reverse lock increase SR trigger SET trigger condition; The actual speed R of steam turbine 实 Subtract the difference of rated speed R 额 Less than-2r / min, DEH side one frequency modulation input, three ways through AND phase and meet the reverse lock function input at the same time trigger 1 to the reverse lock decrease SR trigger SET trigger condition; Step two: actual speed of steam turbine R 实 Subtract the rated speed R 额 The difference is greater than +2r / min trigger 31s pulse delay 30s output, or the actual speed of steam turbine R 实 Subtract the rated speed R 额 The difference is greater than +2r / min trigger delay 30s output as reverse locking increase SR trigger RESET trigger condition 1; the actual speed of steam turbine R 实 Subtract the rated speed R 额 The absolute value of the difference is less than 1.9r / min trigger as reverse locking increase SR trigger RESET trigger condition 2; reverse locking function exit as reverse locking increase SR trigger RESET trigger condition 3; reverse locking decrease activation condition as reverse locking increase SR trigger RESET trigger condition 4; the four paths through OR phase or as reverse locking increase SR trigger RESET; After the reverse lock-in increase condition in step one is activated, it is output to the unit main control AGC target instruction processing logic as the trigger condition of the load increase rate T switching function block. When the trigger condition of the load increase rate T switching function block is 1, the Y loop output is selected, at this time the load increase rate is 0, if it is in the load increase stage at this time, the unit speed limit rate AGC instruction will remain unchanged because the load increase rate is 0; when the trigger condition of the load increase rate T switching function block is 0, the N loop output is selected, at this time the load increase rate is the operating personnel setting value, and the unit speed limit rate AGC instruction changes according to the load increase rate following the AGC target instruction; After the reverse lock-in decrease condition in step one is activated, it is output to the unit main control AGC target instruction processing logic as the trigger condition of the load decrease rate T switching function block. When the trigger condition of the load decrease rate T switching function block is 1, the Y loop output is selected, at this time the load decrease rate is 0, if it is in the load decrease stage at this time, the unit speed limit rate AGC instruction will remain unchanged because the load decrease rate is 0; when the trigger condition of the load decrease rate T switching function block is 0, the N loop output is selected, at this time the load decrease rate is the operating personnel setting value, and the unit speed limit rate AGC instruction changes according to the load increase rate following the AGC target instruction.

2. The control method based on the one-time frequency modulation priority action AGC reverse lockout of claim 1, characterized in that: The lock-in action reset condition pulse signal 30s in step two is a pulse signal of "1".

3. The control method of claim 1, wherein the method further comprises: The rated rotational speed R 额 is 3000 r / min.

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