Optimization method for frequency modulation and AGC lockout examination

Abstract

The application provides a primary frequency modulation and AGC locking examination optimization method, and belongs to the technical field of power station operation control. The method adds a primary frequency modulation monitoring program in an LCU program. When the primary frequency modulation action exceeds 3 seconds, the load setting value tracks the average value of the load in the previous 10 seconds before the primary frequency modulation action. If the primary frequency modulation action is less than 3 seconds, the load instruction tracks the secondary frequency modulation instruction. If the primary frequency modulation action is less than 60 seconds after the locking, the total locking time is 60 seconds. When the primary frequency modulation action exceeds 60 seconds and the primary frequency modulation action signal returns, the locking function of the primary frequency modulation on the AGC is immediately released. The application can fully avoid the reverse adjustment of the primary frequency modulation, improve the control efficiency, and has outstanding technical advantages and good operation performance.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of power station operation control, and particularly relates to a primary frequency modulation and AGC lockout examination optimization method. BACKGROUND

[0002] The primary frequency modulation refers to an automatic control process that when the frequency of a power grid deviates from a rated value, the control system of a unit in the power grid automatically controls the increase and decrease of active power of the unit, limits the change of the frequency of the power grid, and maintains the stability of the frequency of the power grid.

[0003] On February 17, 2024, the applicant generated a primary frequency modulation examination: 60636.76 yuan for No. 1 unit, 65884.96 yuan for No. 2 unit, 36477.68 yuan for No. 3 unit, and 40632.66 yuan for No. 4 unit. The examination generation time period is 21:32-21:40 on February 17. The unit operation conditions of the whole field are that No. 1, No. 2, No. 3 and No. 4 units are in power generation operation. The time period of 21:30-21:45 is the time period for No. 3 unit to reduce load and stop. The unit stop priority order is No. 3, No. 2, No. 4 and No. 1.

[0004] The load of Unit 3 was reduced to 220 MW during the process of load reduction and shutdown, and the grid frequency was reduced to 49.92 Hz. At 21:33:57, the primary frequency regulation of the four units was activated. After the primary frequency regulation of Units 1 and 4 was activated, the actual power output reached 306 MW, and lasted for 11 seconds to 21:34:08. The primary frequency regulation returned to the AGC, and the load of the four units was evenly distributed, i.e. the load of the shutdown unit Unit 3 and the standby unit Unit 2 was stopped, and the power of Units 3 and 4 was simultaneously set to 280 MW. After the primary frequency regulation returned, the actual power output of the four units immediately tracked the active power set value of 280 MW, and the actual power output of the four units was around 280 MW. Then, the primary frequency regulation was activated again, and the speed governor was activated at 21:35:25, and the primary frequency regulation returned at 21:35:32 (the primary frequency regulation lasted for 7 seconds); the speed governor was activated at 21:35:47, and the primary frequency regulation returned at 21:35:55 (the primary frequency regulation lasted for 8 seconds); the speed governor was activated at 21:37:32, and the primary frequency regulation returned at 21:37:48 (the primary frequency regulation lasted for 16 seconds); the speed governor was activated at 21:37:56, and the primary frequency regulation returned at 21:38:14 (the primary frequency regulation lasted for 18 seconds); the speed governor was activated at 21:38:20, and the primary frequency regulation returned at 21:38:38 (the primary frequency regulation lasted for 18 seconds); the speed governor was activated at 21:38:45, and the primary frequency regulation returned at 21:38:55 (the primary frequency regulation lasted for 10 seconds). After the above primary frequency regulation, the primary frequency regulation of the four units was no longer adjusted, and the load of the four units was maintained at 280 MW, and the power output of the whole plant remained at the load value before the primary frequency regulation at 21:33:57.

[0005] From a single unit, 21:33:57, 1, 4 units in full load 300MW operation, to adjust the primary frequency modulation, low frequency primary frequency modulation action after the actual power reaches 306MW operation, primary frequency modulation correct action, but after the primary frequency modulation regression, AGC 1, 4 unit load distribution value is given as 280MW, the monitoring is not set to lock the load adjustment within 1 minute after the primary frequency modulation action, resulting in 21:34:08 after the primary frequency modulation regression, the unit tracks 280MW set value operation, until 21:44:06, 3 unit GCB brake, 1, 4 unit load distribution value changes to 300MW, so 1, 4 units in this 10 minutes integral power produces larger deviation. 2, 3 units should be in primary frequency modulation action with actual load value primary frequency modulation adjustment, at this time 3 unit load has dropped to 220MW, primary frequency modulation does not lock the load adjustment, AGC gives the load distribution value as 280MW, 3 unit actual power rises to 280MW, 2 unit also tracks 280MW operation; 21:40:00 AGC re 2, 3 unit shutdown load reduction and accompany shutdown load reduction, 21:44:06, 3 unit GCB brake, 2 unit load distribution value changes to 300MW, resulting in 2, 3 units in this 6 minute period integral power produces larger deviation. SUMMARY

[0006] The present application aims at the technical defects of the prior art, and provides a primary frequency modulation and AGC lockout optimization method to solve the technical problem that the primary frequency modulation is prone to reverse adjustment under the conventional method.

[0007] To achieve the above technical purpose, the present application adopts the following technical scheme:

[0008] The primary frequency modulation and AGC lockout optimization method comprises the following steps: at the LCU end, when the primary frequency modulation action time exceeds 3 seconds, the load set value monitored by the monitoring is tracked to the average load value 10 seconds before the primary frequency modulation action; if it does not exceed 3 seconds, the load set value is tracked to the secondary frequency modulation instruction; when the secondary frequency modulation lockout is triggered, if the primary frequency modulation action time is less than 60 seconds, the secondary frequency modulation reverse adjustment instruction is locked for 60 seconds, and if the primary frequency modulation action time exceeds 60 seconds, when the primary frequency modulation action signal is reset, the lockout function of the primary frequency modulation to the secondary frequency modulation is immediately released.

[0009] Preferably, the method is realized by a primary frequency modulation monitoring program in the LCU program.

[0010] Preferably, the method further comprises the following steps: at the AGC end, ensuring that the primary frequency modulation action period does not cause the unit load fluctuation to exceed a certain value, and re-distributes the load; confirming the AGC source program high frequency lockout load increase instruction and low frequency lockout load decrease instruction function.

[0011] As preferred, the method further comprises: at the governor end, when the primary frequency modulation action immediately locks the load setting value, the primary frequency modulation action is returned within 3 seconds, and the locking function is released; when the primary frequency modulation action is more than 3 seconds and less than 60 seconds, the locking is continued for 57 seconds; when the primary frequency modulation action is more than 60 seconds and the primary frequency modulation signal is returned, the locking function of the primary frequency modulation to the AGC is immediately released.

[0012] As preferred, in the method, the locking function is only executed when the load is more than 145 MW.

[0013] As preferred, in the method, the steps at the LCU end and the steps at the governor end are alternatively started.

[0014] The application provides a primary frequency modulation and AGC locking optimization method. The method adds a primary frequency modulation monitoring program in an LCU program. When the primary frequency modulation action is more than 3 seconds, the load setting value tracks the average load value in the previous 10 seconds before the primary frequency modulation action. When the primary frequency modulation action is less than 3 seconds, the load instruction tracks the secondary frequency modulation instruction. When the primary frequency modulation action is less than 60 seconds after the locking, the total locking time is 60 seconds. When the primary frequency modulation action is more than 60 seconds and the primary frequency modulation signal is returned, the locking function of the primary frequency modulation to the AGC is immediately released. The application can fully avoid the reverse adjustment of the primary frequency modulation, improve the control efficiency, has outstanding technical advantages and good operation performance. BRIEF DESCRIPTION OF DRAWINGS

[0015] Figure 1 is a schematic diagram of the added variable in the embodiment 1 of the application.

[0016] Figure 2 is a schematic diagram of the assignment of Pid_Para to PFR_P_Min in the embodiment 1 of the application.

[0017] Figure 3 is a schematic diagram of the function of the PID_P shielding the primary frequency modulation action from exiting the PID regulation in the embodiment 1 of the application.

[0018] Figure 4 is a schematic diagram of the protection of the Pid_P increasing the primary frequency modulation action from shielding the regulation without change in the embodiment 1 of the application.

[0019] Figure 5 is a schematic diagram of the storage of the P_Set_CCS data by Recv in the embodiment 1 of the application. DETAILED DESCRIPTION

[0020] The specific embodiments of the present application will be described in detail below. In order to avoid excessive unnecessary details, the well-known structures or functions will not be described in detail in the following examples. The approximate language used in the following examples can be used for quantitative expression, indicating that the amount can be allowed to have certain variation without changing the basic function. Unless defined, the technical and scientific terms used in the following examples have the same meaning as generally understood by those skilled in the art to which the present application belongs. Embodiments

[0021] Primary frequency regulation and AGC lockout optimization method: add primary frequency regulation monitoring program in LCU program, when primary frequency regulation action time exceeds 3 seconds, monitor the load set value issued to track the average load value of 10 seconds before primary frequency regulation action; if it does not exceed 3 seconds, the load set value tracks the secondary frequency regulation instruction. When the secondary frequency regulation lockout is triggered, if the primary frequency regulation action time is less than 60 seconds, the secondary frequency regulation reverse regulation instruction is locked for 60 seconds, if the primary frequency regulation action time exceeds 60 seconds, when the primary frequency regulation action signal returns, the lockout function of primary frequency regulation to secondary frequency regulation is immediately released. In addition, due to program modification, the primary frequency regulation action protection and the active regulation measurement value protection in the original PLC are modified accordingly.

[0022] The program modification process is as follows:

[0023] 1. Add variables (as shown in Figure 1 ).

[0024] 2. Program modification

[0025] 1) Pid_Para increases the assignment of PFR_P_Min (primary frequency regulation lockout function is only executed above 145 MW). (As shown in Figure 2 ).

[0026] 2) PID_P masks the function of primary frequency regulation action exiting PID regulation (primary frequency regulation protection action locks active regulation into power mode). (As shown in Figure 3 ).

[0027] 3) Pid_P increases the protection of primary frequency regulation action masking regulation without change (monitoring system setting measurement value without change protection, when the unit is connected to the grid, the power measurement value changes too small (3s per cycle) for 5 consecutive cycles in the active regulation process, monitoring active regulation exits power mode). (As shown in Figure 4 ).

[0028] 4) Pid_P increases the primary frequency regulation processing related program.

[0029] Program meaning: the primary frequency modulation action is more than 3s, the load set value tracks the average value of the load in the 10s before the primary frequency modulation action; the load instruction tracks the secondary frequency modulation instruction when the primary frequency modulation action is less than 3s. When the primary frequency modulation action is less than 60s after the lockout, the total lockout time is 60s; when the primary frequency modulation action is more than 60s and the primary frequency modulation signal returns, the lockout function of the primary frequency modulation to the AGC is immediately released.

[0030] 5) Recv increases the storage of P_Set_CCS data (as shown in Figure 5 ). Embodiment

[0031] The primary frequency modulation and AGC lockout optimization method comprises:

[0032] I. AGC: the load power distribution strategy is optimized to ensure that the load is not re-distributed (the re-distribution of the load is not triggered) due to the excessive fluctuation of the unit load during the primary frequency modulation action; the functions of the high-frequency lockout load increase instruction and the low-frequency lockout load decrease instruction of the AGC source program are confirmed.

[0033] II. LCU: the primary frequency modulation action is more than 3s, the load set value tracks the average value of the load in the 10s before the primary frequency modulation action; the load instruction tracks the secondary frequency modulation instruction when the primary frequency modulation action is less than 3s. When the primary frequency modulation action is less than 60s after the lockout, the total lockout time is 60s; when the primary frequency modulation action is more than 60s and the primary frequency modulation signal returns, the lockout function of the primary frequency modulation to the AGC is immediately released.

[0034] III. Governor: the load set value is immediately locked out as long as the primary frequency modulation action, the lockout function is released when the primary frequency modulation action returns within 3s, the lockout function is continuously locked for 57s when the primary frequency modulation action is more than 3s and less than 60s, and the lockout function of the primary frequency modulation to the AGC is immediately released (the actual value of the electric governor exchange table is tracked) when the primary frequency modulation action is more than 60s and the primary frequency modulation signal returns.

[0035] On the basis of the above technical solutions:

[0036] 1. The above lockout functions are only executed when the load is more than 145MW.

[0037] 2. Only one of the optimization 2 and the optimization 3 is opened.

[0038] The embodiments of the present application are described in detail above, but the content described is only the preferred embodiments of the present application, and does not limit the present application. Any modification, equivalent replacement and improvement made within the application scope of the present application shall be included in the protection scope of the present application.

Claims

1. A method for optimizing the examination of frequency modulation and AGC lock, characterized in that, The method comprises the following steps: At the LCU end, if the time of primary frequency modulation action is more than 3 seconds, the monitoring of the issued load setting value tracks the average load value in the 10 seconds before the primary frequency modulation action; If the time of primary frequency modulation action is less than 3 seconds, the load setting value tracks the secondary frequency modulation instruction; if the time of primary frequency modulation action is less than 60 seconds after the secondary frequency modulation is triggered, the secondary frequency modulation reverse regulation instruction is blocked for 60 seconds; if the time of primary frequency modulation action is more than 60 seconds, the blocking function of primary frequency modulation to the secondary frequency modulation is immediately released when the primary frequency modulation signal returns.

2. The method of claim 1, wherein, The method is realized by a primary frequency modulation monitoring program in the LCU program.

3. The method of claim 1, wherein the method further comprises: The method further comprises the following steps: at the AGC end, during the primary frequency modulation action, the load is not re-allocated due to the fluctuation of the unit load exceeding a certain value; the functions of the high-frequency blocking load increase instruction and the low-frequency blocking load decrease instruction of the AGC source program are confirmed.

4. The method of claim 3, wherein the method further comprises: The method further comprises the following steps: at the governor end, when the primary frequency modulation action immediately blocks the load setting value, the blocking function is released within 3 seconds after the primary frequency modulation action returns; the blocking function is continuously blocked for 57 seconds when the time of primary frequency modulation action is more than 3 seconds and less than 60 seconds; the blocking function of primary frequency modulation to the AGC is immediately released when the time of primary frequency modulation action is more than 60 seconds and the primary frequency modulation signal returns.

5. The method of claim 4, wherein, In the method, the steps at the LCU end and the steps at the governor end are alternatively started.

Images