Hydropower station lcu opening degree analog quantity segmented open-loop control method and system

Abstract

The application discloses a kind of LCU opening degree analog quantity segmented open-loop control method and system of hydropower station;The application is a kind of LCU opening degree analog quantity segmented open-loop control method of hydropower station in opening and closing two directions;It is optimized on the basis of the original direction guide vane opening degree analog quantity segmented open-loop control method, and the opening and closing two directions of hydropower station monitoring system opening degree mode guide vane opening degree analog quantity open-loop control is realized by increasing direction coefficient;It has the characteristics of open-loop control fast, and also has the advantage that segmented open-loop control overshoot is small, to meet the requirements of regulating process speediness good, overshoot small simultaneously, improve dynamic regulation quality.

Description

Technical Field

[0001] This invention relates to the field of computer monitoring technology for hydropower stations, and in particular to a segmented open-loop control method and system for LCU opening degree analog quantity in hydropower stations. Background Technology

[0002] Currently, during the operation of hydro-generator units, the monitoring system in the opening mode typically adopts a conventional closed-loop power pulse regulation method. This method uses an intermediate relay to output opening increase / decrease pulses to the governor's electronic control system to control the turbine generator unit's opening. However, this approach suffers from problems such as slow guide vane opening and active power regulation speeds, and susceptibility to water hammer and unit inertia. To overcome these shortcomings, the invention patent "Segmented Open-Loop Control Method and System for Guide Vane Opening Analog Quantity" (ZL202011420862.1) discloses a method and system. This method, based on a data table corresponding to head, active power, and guide vane opening, employs a lookup-based approach in opening mode to rapidly and accurately adjust the unit's active power, outputting a novel analog control signal for guide vane opening. It aims to address the problems of slow active power adjustment speed and susceptibility to water hammer and unit inertia in conventional closed-loop pulse regulation in opening mode, thereby improving the speed of regulation and achieving rapid and stable control of both guide vane opening and active power, thus enhancing regulation quality. However, this method only implements a segmented open-loop analog control method for guide vane opening in the opening direction of a hydropower station's LCU. This application builds upon this method, researching and improving upon it to optimize the approach. Summary of the Invention

[0003] To address the problems existing in the prior art, the purpose of this invention is to provide a segmented open-loop control method and system for the analog quantity of LCU opening in hydropower stations. This invention can realize bidirectional segmented open-loop control of the switch, which has both the characteristics of fast open-loop control and the advantages of small overshoot in segmented open-loop control, thus simultaneously meeting the requirements of good speed and small overshoot in the regulation process and improving the quality of dynamic regulation.

[0004] To achieve the above objectives, the technical solution adopted by this invention is: a segmented open-loop control method for the analog quantity of LCU opening degree in a hydropower station, comprising the following steps:

[0005] S1. Initialize the control parameters △D, △D1, directional coefficient k, amplitude limiting coefficient K1 of the monitoring system, and initialize the data in the one-to-one correspondence table of head, active power and guide vane opening. Proceed to step 2.

[0006] S2, The monitoring system collects the active power setpoint G. 给定 Power feedback G, guide vane opening feedback D, unit head w;

[0007] S3. The monitoring system checks whether it is in open mode. If yes, proceed to step S4; otherwise, use non-open mode control and return to step S2.

[0008] S4. The monitoring system detects the active power setpoint G. 给定 Refresh? If yes, proceed to step S5; otherwise, proceed to step S9.

[0009] S5. The monitoring system is based on the active power setpoint G. 给定 By referring to the data table that corresponds one-to-one between the current unit head (w), active power, and guide vane opening, the corresponding guide vane opening value (D) can be calculated. 表 .

[0010] S6, Control Variable D 控制 Assign an initial value D;

[0011] S7, Monitoring System Detection D 表 If the value increases, k=1 and proceed to step S9; otherwise, proceed to step S8.

[0012] S8, Monitoring System Detection D 表 If the value decreases, k = -1, proceed to step S9; otherwise, proceed directly to step S9.

[0013] S9. Monitoring system checks whether |D 表 -D∣≧△D1, if so, then D 控制 =D 控制 +k*△D, where △D is the increment / decrement step size for the control parameter, proceed to step S10; otherwise, D 控制 =D 控制 -k*△D, proceed to step S14;

[0014] S10. The monitoring system checks whether k=1. If yes, proceed to step S11; otherwise, proceed to step S12.

[0015] S11, Monitoring system detects whether D 控制 >K1*D 表 If so, then D 控制 =K1*D 表 If yes, proceed to step S18; otherwise, proceed directly to step S18.

[0016] S12. The monitoring system checks whether k=-1. If yes, proceed to step S13; otherwise, proceed to step S18.

[0017] S13. Monitoring system checks whether D is present. 控制 <K1*D 表 If so, then D 控制 =K1*D 表If yes, proceed to step S18; otherwise, proceed directly to step S18.

[0018] S14. The monitoring system checks whether k=1. If yes, proceed to step S15; otherwise, proceed to step S16.

[0019] S15. Monitoring system checks whether D... 控制 <D 表 If so, then D 控制 =D 表 If yes, proceed to step S18; otherwise, proceed directly to step S18.

[0020] S16. The monitoring system checks whether k=-1. If yes, proceed to step S17; otherwise, proceed to step S18.

[0021] S17. Monitoring system checks whether D is present. 控制 >D 表 If so, then D 控制 =D 表 If yes, proceed to step S18; otherwise, proceed directly to step S18.

[0022] S18, The monitoring system outputs an analog control signal for the guide vane opening. 控制 Return to step S2.

[0023] As a further improvement to the present invention, step S5 is specifically as follows:

[0024] The data table showing the one-to-one correspondence between head, active power, and guide vane opening is as follows:

[0025]

[0026] In the table above, p, q, x, and y are all positive integers, 1 < x ≤ p, 1 < y ≤ q, and Dx,y is the guide vane opening corresponding to the active power of Wx head Gy.

[0027] If W x-1 ≤w≤W x G y-1 ≤G 给定 ≤G y ,but:

[0028] d 表y-1 =D x-1，y-1 +(D) x，y-1 -D x-1，y-1 (wW) x-1 ) / (W x -W x-1 );

[0029] d 表y =D x-1，y +(D) x，y -Dx-1，y (wW) x-1 ) / (W x -W x-1 );

[0030] D 表 =d 表y-1 +(d 表y -d 表y-1 (G) 给定 -G y-1 ) / (G y -G y-1 ).

[0031] The present invention also provides a segmented open-loop control system for the analog quantity of LCU opening degree in a hydropower station, comprising:

[0032] The lookup table calculation module is used to collect the active power command G. 给定 Given the unit head w, refer to the table showing the one-to-one correspondence between head, active power, and guide vane opening to calculate and output the calculation result D. 表 Provide the limiting module 1 and the limiting module 2;

[0033] The cyclic incrementing module is used to monitor D. 表 Change and |D 表 -D∣≧△D1 enable signal, and acquire guide vane opening signal D; when the enable signal is activated for the first time, D 控制 Assign an initial value D; the loop increment module continuously increments D. 控制 The loop increments by k*ΔD and outputs D. 控制 Apply the limiter to module 1;

[0034] The limiting module 1 is used to collect the D output from the lookup table calculation module. 表 and the output D of the loop increment module 控制 , for D 控制 For amplitude limiting output, if k=1, the maximum value is K1*D. 表 If k=-1, then the minimum value is K1*D 表 Output guide vane opening analog control signal D 控制 Assign channel 0 to the selector module;

[0035] The cyclic decrement module is used to monitor |D 表 -D∣<△D1 enable signal, and acquire guide vane opening signal D; the cyclic self-decreasing module continuously adjusts D. 控制 The loop decrements by k*ΔD, and outputs D. 控制 Apply the limiter to module 1;

[0036] The limiting module 2 is used to collect the D output from the lookup table calculation module 1. 表 and the output D of the loop decrement module 控制 , for D 控制For amplitude limiting output, if k=1, the minimum value is D. 表 If k=-1, then the maximum value is D. 表 Output guide vane opening analog control signal D 控制 Give channel 1 to the selector module;

[0037] The selector module is used to monitor |D 表 -D∣<△D1 selects the signal and acquires the analog control signal D of the guide vane opening output from limiter module 1 and limiter module 2 to the selector module. 控制 When |D 表 When -D∣<△D1 is not satisfied, the selector module selects channel 0 and outputs the guide vane opening analog control signal D from the limiting module to the selector module. 控制 When |D 表 When -D∣<△D1 is satisfied, the selector module selects channel 1 and outputs the guide vane opening analog control signal D from the limiting module 2 to the selector module. 控制 The selector module converts the guide vane opening analog control signal D... 控制 The output is sent to the speed controller's electronic control system.

[0038] The beneficial effects of this invention are:

[0039] The control method of this invention can realize bidirectional segmented open-loop control, possessing both the fast characteristics of open-loop control and the small overshoot advantage of segmented open-loop control. This simultaneously satisfies the requirements of good speed and small overshoot in the adjustment process, thus improving the quality of dynamic adjustment. Specifically, it is reflected in:

[0040] 1. Achieve bidirectional segmented open-loop control of the switch.

[0041] 2. It features rapid open-loop regulation, thereby improving the speed of the regulation process.

[0042] 3. It can further improve the speed of the adjustment process, while avoiding the problem of excessive overshoot caused by excessive adjustment speed, thereby improving the adjustment quality of the adjustment process.

[0043] 4. Open-loop control can avoid the effects of water hammer reaction and unit inertia during the adjustment process, reducing the risk of divergent oscillations in the entire control system. Attached Figure Description

[0044] Figure 1 This is a flowchart of the segmented open-loop control of the LCU opening degree analog quantity of a hydropower station in an embodiment of the present invention;

[0045] Figure 2 This is a diagram of the segmented open-loop control structure for the guide vane opening analog quantity in the LCU opening mode of a hydropower station, as shown in this embodiment of the invention. Detailed Implementation

[0046] The power plant monitoring system is generally divided into two levels: the plant level and the local control unit level. The local control unit level is connected to the power plant control network and uses fieldbus technology to complete the local monitoring tasks of designated equipment.

[0047] In this invention, the monitoring system specifically refers to the local control unit layer, which is distributed according to the controlled object units and consists of various local control units (LCUs) throughout the plant, including the LCUs of each generating unit, the plant power LCU, the public utility LCU, the switchyard LCU, and the dam crest LCU. Each local control unit (LCU) includes PLCs, touch screens, network equipment, cabinets, etc., and is responsible for equipment data acquisition and processing, equipment status monitoring and process monitoring, equipment control and regulation, and equipment information communication.

[0048] The unit's LCU PLC uses the Unity Quantum 67261 controller manufactured by Schneider Electric of France.

[0049] The open-loop control method and system for analog LCU opening degree of hydropower stations of the present invention were applied to the monitoring system of a power plant.

[0050] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0051] Example

[0052] like Figure 1 As shown, the detailed process steps of a segmented open-loop control of the LCU opening degree in a hydropower station are as follows:

[0053] 1. Initialize the data in the one-to-one correspondence table between the monitoring system control parameters △D, △D1, directional coefficient k, amplitude limiting coefficient K1, head, active power and guide vane opening, and proceed to step 2.

[0054] 2. The monitoring system collects the variable active power setpoint G. 给定 Power feedback G, guide vane opening feedback D, unit head w, proceed to step 3.

[0055] 3. The monitoring system checks whether it is in open mode. If so, proceed to step 4; otherwise, use the non-open mode control method and return to step 2.

[0056] 4. The monitoring system detects the active power setpoint G. 给定 Refresh? If yes, proceed to step 5; otherwise, proceed to step 9.

[0057] 5. The monitoring system is based on the active power setpoint G. 给定 By referring to the data table that corresponds one-to-one between the current unit head (w), active power, and guide vane opening, the corresponding guide vane opening value (D) can be calculated. 表 .

[0058] Table 1 shows the one-to-one correspondence between head, active power, and guide vane opening. (In the table, p, q, x, and y are all positive integers, 1 < x ≤ p, 1 < y ≤ q, and Dx,y is the guide vane opening corresponding to Wx head and Gy active power.)

[0059] Table 1. Correspondence between water head, active power, and guide vane opening.

[0060]

[0061] If W x-1 ≤w≤W x G y-1 ≤G 给定 ≤G y ,but:

[0062] d 表y-1 =D x-1，y-1 +(D) x，y-1 -D x-1，y-1 (wW) x-1 ) / (W x -W x-1 ).

[0063] d 表y =D x-1，y +(D) x，y -D x-1，y (wW) x-1 ) / (W x -W x-1 ).

[0064] D 表 =d 表y-1 +(d 表y -d 表y-1 (G) 给定 -G y-1 ) / (G y -G y-1 Proceed to step 6.

[0065] 6. Control variable D 控制 Assign an initial value D and proceed to step 7.

[0066] 7. Monitoring system detects D 表 If the value increases, k=1 and proceed to step 9; otherwise, proceed to step 8.

[0067] 8. Monitoring system detects D 表 If the value decreases, k = -1, proceed to step 9; otherwise, proceed to step 9.

[0068] 9. The monitoring system checks whether |D 表 -D∣≧△D1, if so, then D 控制 =D 控制+k*△D, where △D is the step size for increasing or decreasing the control parameter, proceed to step 10; otherwise, D 控制 =D 控制 -k*△D, proceed to step 14.

[0069] 10. The monitoring system checks if k=1. If yes, proceed to step 11; otherwise, proceed to step 12.

[0070] 11. The monitoring system checks whether D is present. 控制 >K1*D 表 If so, then D 控制 =K1*D 表 Proceed to step 18 if the condition is met; otherwise, proceed to step 18.

[0071] 12. The monitoring system checks if k=-1. If yes, proceed to step 13; otherwise, proceed to step 18.

[0072] 13. The monitoring system checks whether D is present. 控制 <K1*D 表 If so, then D 控制 =K1*D 表 Proceed to step 18 if the condition is met; otherwise, proceed to step 18.

[0073] 14. The monitoring system checks if k=1. If yes, proceed to step 15; otherwise, proceed to step 16.

[0074] 15. The monitoring system checks whether D is present. 控制 <D 表 If so, then D 控制 =D 表 Proceed to step 18 if the condition is met; otherwise, proceed to step 18.

[0075] 16. The monitoring system checks if k=-1. If yes, proceed to step 17; otherwise, proceed to step 18.

[0076] 17. The monitoring system checks whether D is present. 控制 >D 表 If so, then D 控制 =D 表 Proceed to step 18 if the condition is met; otherwise, proceed to step 18.

[0077] 18. The monitoring system outputs an analog control signal D for the guide vane opening. 控制 Return to step 2.

[0078] The following is a diagram of the segmented open-loop control structure for the guide vane opening analog quantity in a hydropower station monitoring system according to this embodiment: Figure 2 As shown, it mainly consists of a lookup table calculation module 1, a cyclic increment module 2, a limiter module 3, a cyclic decrement module 4, a limiter module 5, and a selector module 6.

[0079] Table lookup and calculation module 1 collects active power command G 给定 Given the unit head w, refer to the table showing the one-to-one correspondence between head, active power, and guide vane opening to calculate and output the calculation result D. 表 Apply the limiter module 3 and the limiter module 5.

[0080] Cyclic self-incrementing module 2 monitors D 表 Change and |D 表 -D|≧△D1 enables the signal and acquires the guide vane opening signal D. When the enable signal is activated for the first time, D 控制 Assign an initial value D. The incrementing loop module 2 continuously increments D. 控制 The loop increments by k*ΔD and outputs D. 控制 Apply the limiter to module 3.

[0081] The limiting module 3 acquires the D output of the table lookup and calculation module 1. 表 and the output D of the cyclic increment module 2 控制 , for D 控制 For amplitude limiting output, if k=1, the maximum value is K1*D. 表 If k=-1, then the minimum value is K1*D 表 K1 is typically set to 1.4. The output guide vane opening analog control signal D... 控制 Give the selector module 6 channels 0.

[0082] Cyclic Decrease Module 4 Monitoring | D 表 -D∣<△D1 enable signal, and acquire guide vane opening signal D. The cyclic decrement module 4 continuously adjusts D. 控制 The loop decrements by k*ΔD, and outputs D. 控制 Give the amplitude limiting module 3.

[0083] The limiting module 5 acquires the D output of the table lookup and calculation module 1. 表 and the output D of the cyclic decrement module 4 控制 , for D 控制 For amplitude limiting output, if k=1, the minimum value is D. 表 If k=-1, then the maximum value is D. 表 Output guide vane opening analog control signal D 控制 Give the selector module 6 channels 1.

[0084] Selector module 6 monitors |D 表 -D∣<△D1 selects the signal and acquires the guide vane opening analog control signal D output from limiter module 1 3 and limiter module 2 5 to selector module 6. 控制 When |D 表When -D∣<△D1 is not satisfied, selector module 6 selects channel 0 and outputs the guide vane opening analog control signal D output by limiting module 3 to selector module 6. 控制 When |D 表 When -D∣<△D1 is satisfied, selector module 6 selects channel 1 and outputs the guide vane opening analog control signal D output by limiting module 5 to selector module 6. 控制。 Selector module 6 will convert the guide vane opening analog control signal D 控制 The output is sent to the speed controller's electronic control system.

[0085] The embodiments described above are merely illustrative of specific implementations of the present invention, and while the descriptions are detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention.

Claims

1. A segmented open-loop control method for the analog quantity of LCU opening degree in a hydropower station, characterized in that, Includes the following steps: S1. Initialize the monitoring system control parameters △D, △D1, directional coefficient k, amplitude limiting coefficient K1, and initialize the data in the one-to-one correspondence table of head, active power and guide vane opening, then proceed to step 2. S2, Monitoring system collects variable active power setpoint G 给定 Power feedback G, guide vane opening feedback D, unit head w; S3. The monitoring system checks whether it is in open mode. If yes, proceed to step S4; otherwise, use non-open mode control and return to step S2. S4. The monitoring system detects the active power setpoint G. 给定 Refresh? If yes, proceed to step S5. Otherwise, proceed to step S9; S5. The monitoring system is based on the active power setpoint G. 给定 By referring to the table corresponding to the current unit head w, active power, and guide vane opening, the corresponding guide vane opening value D is calculated. 表 ; Step S5 is as follows: The table below shows the one-to-one correspondence between head, active power, and guide vane opening: ； In the table above, p, q, x, and y are all positive integers, 1 < x ≤ p, 1 < y ≤ q, and Dx,y is the guide vane opening corresponding to the active power of Wx head Gy. If W x-1 ≤w≤W x G y-1 ≤G 给定 ≤G y ,but: d 表y-1 =D x-1，y-1 +(D x，y-1 -D x-1，y-1 )(w-W x-1 ) / (W x -W x-1 ); d 表y =D x-1，y +(D x，y -D x-1，y )(w-W x-1 ) / (W x -W x-1 ); D 表 =d 表y-1 +(d 表y -d 表y-1 )(G 给定 -G y-1 ) / (G y -G y-1 ); S6, Control Variable D 控制 Assign an initial value D; S7, Monitoring System Detection D 表 Does it increase? If so, k=1, proceed to step S9; Otherwise, proceed to step S8; S8, Monitoring System Detection D 表 If the value decreases, k = -1, proceed to step S9; otherwise, proceed directly to step S9. S9. Monitoring system checks if |D 表 -D∣≧△D1, if so, then D 控制 =D 控制 +k*△D, where △D is the step size for increasing or decreasing the control parameter, proceed to step S10; Otherwise, D 控制 =D 控制 -k*△D, proceed to step S14; S10. The monitoring system checks whether k=1. If so, proceed to step S11. Otherwise, proceed to step S12; S11, Monitoring system detects whether D 控制 >K1*D 表 If so, then D 控制 =K1*D 表 If yes, proceed to step S18; otherwise, proceed directly to step S18. S12. The monitoring system checks whether k=-1. If so, proceed to step S13. Otherwise, proceed to step S18; S13. Monitoring system checks whether D is present. 控制 <K1*D 表 If so, then D 控制 =K1*D 表 If yes, proceed to step S18; otherwise, proceed directly to step S18. S14. The monitoring system checks whether k=1. If yes, proceed to step S15; otherwise, proceed to step S16. S15. Monitoring system checks whether D... 控制 <D 表 If so, then D 控制 =D 表 If yes, proceed to step S18; otherwise, proceed directly to step S18. S16. The monitoring system checks whether k=-1. If so, proceed to step S17. Otherwise, proceed to step S18; S17. Monitoring system checks whether D is present. 控制 >D 表 If so, then D 控制 =D 表 If yes, proceed to step S18; otherwise, proceed directly to step S18. S18, The monitoring system outputs an analog control signal for the guide vane opening. 控制 Return to step S2.

2. A segmented open-loop control system for the analog quantity of LCU opening in a hydropower station, characterized in that, For executing the segmented open-loop control method for analog LCU opening degree of a hydropower station as described in claim 1, the control system includes: The lookup table calculation module is used to collect the active power command G. 给定 Given the unit head w, refer to the table showing the one-to-one correspondence between head, active power, and guide vane opening to calculate and output the calculation result D. 表 Provide the limiting module 1 and the limiting module 2; The table below shows the one-to-one correspondence between head, active power, and guide vane opening: ； In the table above, p, q, x, and y are all positive integers, 1 < x ≤ p, 1 < y ≤ q, and Dx,y is the guide vane opening corresponding to the active power of Wx head Gy. If W x-1 ≤w≤W x G y-1 ≤G 给定 ≤G y ,but: d 表y-1 =D x-1，y-1 +(D x，y-1 -D x-1，y-1 )(w-W x-1 ) / (W x -W x-1 ); d 表y =D x-1，y +(D x，y -D x-1，y )(w-W x-1 ) / (W x -W x-1 ); D 表 =d 表y-1 +(d 表y -d 表y-1 )(G 给定 -G y-1 ) / (G y -G y-1 ); The cyclic incrementing module is used to monitor D. 表 Change and |D 表 -D∣≧△D1 enable signal, and acquire guide vane opening signal D; when the enable signal is activated for the first time, D 控制 Assign an initial value D; the loop increment module continuously increments D. 控制 The loop increments by k*ΔD, where ΔD is the control parameter of the monitoring system, and outputs D. 控制 Apply the limiter to module 1; The limiting module 1 is used to collect the D output from the lookup table calculation module. 表 and the output D of the loop increment module 控制 , for D 控制 For amplitude limiting output, if k=1, the maximum value is K1*D. 表 If k=-1, then the minimum value is K1*D 表 K1 is the limiting coefficient; the output guide vane opening analog control signal D 控制 Assign channel 0 to the selector module; The cyclic decrement module is used to monitor |D 表 -D∣<△D1 enable signal, and acquire guide vane opening signal D; the cyclic self-decreasing module continuously adjusts D. 控制 The loop decrements by k*ΔD, and outputs D. 控制 To limit the amplitude to module 2; The limiting module 2 is used to collect the D output from the lookup table calculation module. 表 and the output D of the loop decrement module 控制 , for D 控制 For amplitude limiting output, if k=1, the minimum value is D. 表 If k=-1, then the maximum value is D. 表 Output guide vane opening analog control signal D 控制 Give channel 1 to the selector module; The selector module is used to monitor |D 表 -D∣<△D1 selects the signal and acquires the analog control signal D of the guide vane opening output from limiter module 1 and limiter module 2 to the selector module. 控制 When |D 表 When -D∣<△D1 is not satisfied, the selector module selects channel 0 and outputs the guide vane opening analog control signal D from the limiting module to the selector module. 控制 When |D 表 When -D∣<△D1 is satisfied, the selector module selects channel 1 and outputs the guide vane opening analog control signal D from the limiting module 2 to the selector module. 控制 The selector module converts the guide vane opening analog control signal D... 控制 The output is sent to the speed controller's electronic control system.

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