Intelligent locking control method for primary frequency modulation of supercritical generator set

Abstract

The application discloses a kind of supercritical generator set primary frequency modulation intelligent blocking control methods, according to primary frequency modulation blocking trigger instruction steam turbine control blocking instruction is sent;And when frequency difference protection instruction and boiler protection instruction are triggered, send coal control blocking instruction;When primary frequency modulation response contribution electric quantity meets the requirement of frequency variation, by blocking recovery loop sends blocking recovery instruction, realizes intelligent blocking control, guarantees the priority of primary frequency modulation adjustment, prevents AGC instruction is long-term blocked and influences AGC normal adjustment, causes unit to grid frequency again disturbance.

Description

Technical Field

[0001] This invention relates to an intelligent interlocking control method for primary frequency regulation of a supercritical generator set. Background Technology

[0002] With the rapid development of new energy sources such as wind power and photovoltaics, and the implementation and operation of large-scale ultra-high voltage direct current (UHVDC) transmission projects, the power grid structure is becoming increasingly complex, and the phenomenon of power grid frequency instability is increasing. Therefore, it is essential that generating units possess the ability to quickly respond to changes in automatic generation control (AGC) commands and primary frequency regulation demands. However, during the rapid response process, situations often arise where the direction of AGC command changes is opposite to the direction of primary frequency regulation, thereby weakening the contribution of primary frequency regulation and preventing the power grid frequency from stabilizing quickly. Summary of the Invention

[0003] This invention addresses the shortcomings of existing technologies by providing an intelligent interlocking control method for primary frequency regulation of supercritical generator sets. This method eliminates the phenomenon where the generator set's AGC commands and primary frequency regulation commands weaken the contribution of primary frequency regulation due to reversed adjustments. It not only ensures the priority of primary frequency regulation but also prevents the generator set from causing further disturbances to the grid frequency due to the long-term interlocking of AGC commands affecting normal AGC regulation. This guarantees the accuracy and stability of the generator set's rapid response to changes in grid frequency.

[0004] To achieve its objectives, the present invention employs the following technical solution:

[0005] The intelligent interlocking control method for primary frequency regulation of supercritical generator sets of the present invention is characterized by: issuing a turbine control interlocking command based on the interlocking trigger command of primary frequency regulation; issuing a coal feeding control interlocking command when both the frequency difference protection command and the boiler protection command are triggered; and issuing an interlocking recovery command by the interlocking recovery circuit when the power contribution of the primary frequency regulation response meets the frequency change requirements, thereby realizing intelligent interlocking control.

[0006] The intelligent interlocking control method for primary frequency regulation of supercritical generator sets in this invention is also characterized by:

[0007] The interlocking trigger command is obtained by the interlocking trigger circuit based on the unit control mode, main steam pressure and grid frequency; the unit control mode is obtained by the analog controller based on the unit's CCS mode, primary frequency regulation activation and switching switch signals.

[0008] The turbine control lockout command is obtained by the turbine control circuit through judgment in response to the lockout trigger command.

[0009] The coal feeding control interlock command is obtained by the coal feeding control circuit when the frequency difference protection command, boiler protection command, and interlock trigger command are all triggered; the frequency difference protection command is obtained by the frequency difference protection circuit based on the power grid frequency; the boiler protection command is obtained by the boiler protection circuit based on the furnace pressure, main steam temperature, and main steam pressure.

[0010] The lockout recovery command is obtained by the lockout recovery circuit based on the judgment of the unit load, main steam pressure, grid frequency and the status of the manual reset button;

[0011] When the conditions for the primary frequency regulation interlocking trigger circuit of the unit are met, the primary frequency regulation interlocks the turbine control circuit according to the grid frequency disturbance; and interlocks the coal feed control circuit when both the frequency difference protection command and the boiler protection command are triggered.

[0012] The intelligent interlocking control method for primary frequency regulation of supercritical generator sets in this invention is also characterized by the following: the intelligent interlocking control includes interlocking control and interlocking recovery.

[0013] Implement interlocking control as follows:

[0014] Steam turbine control loop interlock control: The interlock triggering loop judges the acquired unit control mode, main steam pressure and grid frequency. If the triggering conditions are met, the interlock triggering command is output as "1" to the S terminal of the RS trigger, and the "1" value of the S terminal of the RS trigger controls the steam turbine control loop to interlock.

[0015] Coal feeding control loop interlock control: Set the following judgment conditions:

[0016] Condition A: The boiler protection circuit judges the acquired furnace pressure, main steam temperature and main steam pressure. If the furnace pressure, main steam temperature and main steam pressure are all within the normal range, the boiler protection command is output as "1" to the A1 interpolator.

[0017] Condition B: The frequency difference protection circuit judges the frequency difference value based on the acquired power grid frequency. If the frequency difference value exceeds the ±0.1Hz large frequency difference judgment limiter, the frequency difference protection command is output as "1" to the A1 limiter.

[0018] Condition C: The RS flip-flop sends the "1" value instruction at its S terminal to the AND gate A1;

[0019] When conditions A, B, and C all output a "1" value command to the A1 interpolator, the A1 interpolator outputs a "1" value command to control the coal feeding control loop to be locked.

[0020] Lockout recovery is achieved as follows:

[0021] During the primary frequency regulation interlock control of the unit, the interlock recovery circuit obtains the unit load, main steam pressure, grid frequency, and the status of the manual reset button. If any condition is met, an interlock recovery command is output to the R terminal of the RS trigger to reset the interlock commands of the turbine control circuit and the coal feeding control circuit, thereby realizing the interlock recovery.

[0022] The intelligent interlocking control method for primary frequency regulation of supercritical generator sets in this invention is also characterized by:

[0023] When the direction of the frequency regulation action is opposite to the direction of the AGC regulation, and the conditions of the unit's main steam pressure and unit control mode are met, the interlock trigger circuit triggers the interlock AGC increment command or the interlock AGC decrement command in the following manner:

[0024] If a high frequency difference disturbance occurs in the power grid frequency, the blocking trigger circuit outputs a blocking AGC increase command to maintain the unit AGC load increase command; the high frequency difference disturbance is obtained by the high frequency difference limiter judging the frequency difference value, and the high frequency difference limit is set to +0.0333Hz.

[0025] If a low-frequency difference disturbance occurs in the grid frequency, the blocking trigger circuit outputs a blocking AGC reduction command to maintain the unit's AGC load reduction command; the low-frequency difference disturbance is obtained by the low-frequency difference limiter judging the frequency difference value, and the low-frequency difference limit is set to -0.0333Hz.

[0026] The condition for satisfying the main steam pressure is obtained by judging the main steam pressure deviation value through the pressure deviation too high / too low judgment device, and then through the N1 negator.

[0027] The intelligent interlocking control method for primary frequency regulation of supercritical generator sets in this invention is also characterized by:

[0028] The frequency difference protection circuit implements frequency difference protection in the following manner:

[0029] When a disturbance occurs in the power grid frequency, if the frequency difference exceeds the ±0.0333Hz frequency dead zone limiter, a frequency regulation action signal is output. At the same time, the large frequency difference limiter determines whether the power grid frequency disturbance is a large frequency difference disturbance. If it is not a large frequency difference disturbance, the S-terminal output of the RS flip-flop is "0", and the frequency difference protection command is not triggered. If it is a large frequency difference disturbance, the S-terminal output of the RS flip-flop is "1", triggering the frequency difference protection command. The protection duration is set by the T1 timer. When the timer reaches the protection duration, the S-terminal output of the RS flip-flop is reset to avoid the frequency difference protection command lasting too long and causing disturbance to the unit regulation.

[0030] The intelligent interlocking control method for primary frequency regulation of supercritical generator sets in this invention is also characterized by:

[0031] The boiler protection circuit implements boiler protection in the following manner:

[0032] During unit operation, when the main steam pressure, furnace pressure and main steam temperature are all under normal operating conditions, a boiler protection command is generated. This command serves as the condition for determining whether the boiler coal feeding control circuit is locked when the unit responds to the primary frequency regulation action.

[0033] The normal operating conditions of the furnace pressure include that the furnace pressure adjustment does not exceed the limit and the furnace pressure change rate is normal; wherein: the furnace pressure adjustment not exceeding the limit is determined by the furnace pressure too high / too low detector, and then determined by the NOR device H1; the normal furnace pressure change rate is determined by the rise / fall rate detector, which determines the furnace pressure deviation value, and then determined by the NOR device H1.

[0034] The normal operating conditions of the main steam temperature include that the temperature value adjustment of the main steam temperature does not exceed the limit and that the rate of change of the main steam temperature is normal. The condition that the temperature value adjustment of the main steam temperature does not exceed the limit is obtained by judging the main steam temperature value through the main steam temperature too high / too low detector and then through the H2 NOR detector. The condition that the rate of change of the main steam temperature is normal is obtained by judging the main steam temperature deviation value through the rate of decrease detector and then through the H2 NOR detector.

[0035] The intelligent interlocking control method for primary frequency regulation of supercritical generator sets in this invention is also characterized by:

[0036] The lockout restoration is performed when any of the following conditions are met:

[0037] Condition 1: Manual reset, the lockout recovery circuit is manually triggered by the manual reset button to issue a lockout recovery command;

[0038] Condition 2: Frequency difference value returns to frequency modulation dead zone reset. Set a frequency modulation dead zone limiter to determine whether the grid frequency difference value exceeds the frequency modulation dead zone ±0.0333Hz; set an N2 NOT device to determine whether the frequency difference value returns to the frequency modulation dead zone. If the frequency difference value returns to the frequency modulation dead zone, lockout reset.

[0039] Condition 3: Time limit reset. The T2 timer is used to time the output duration of the frequency modulation dead zone limiter. If the duration of a frequency modulation exceeds the set duration, the lockout is reset.

[0040] Condition 4: If the absolute value of the actual load contribution is greater than the theoretical value set for frequency regulation, the lockout will be reset.

[0041] Condition 5: If the power contribution index of frequency modulation operation exceeds 90% for 45 seconds, the lockout will be reset.

[0042] Condition 6: If the main steam pressure deviation is greater than the set value, the interlock will be reset.

[0043] The intelligent interlocking control method for primary frequency regulation of supercritical generator sets in this invention is also characterized by:

[0044] For reset condition four, where the absolute value of the actual load contribution is greater than the theoretical frequency regulation set amplitude, the lockout reset is determined by the overshoot prediction circuit and the undershoot prediction circuit; where:

[0045] The overshoot prediction loop includes: setting up a D1 divider, the actual load change output by the power contribution calculation module is input into the D1 divider, the theoretical load change output by the power contribution calculation module is output by the f(x1) function generator to generate the expected overshoot frequency modulation contribution, and is input into the D1 divider, the D1 divider calculates the overshoot ratio of the actual load change to the expected overshoot frequency modulation contribution, and the overshoot ratio is judged by the overshoot judge to obtain the overshoot prediction signal;

[0046] The under-adjustment prediction loop includes: setting up a D2 divider, the actual load change output by the power contribution calculation module is input into the D2 divider, the theoretical load change output by the power contribution calculation module is output by the f(x2) function generator to generate the under-adjustment expected frequency modulation contribution, and is input into the D2 divider, the D2 divider calculates the ratio of the actual load change to the under-adjustment expected frequency modulation contribution, and the under-adjustment ratio is judged by the under-adjustment judge to obtain the under-adjustment prediction signal;

[0047] The optimal reset command trigger time of the under-adjustment prediction circuit is determined by timer T3 based on whether the frequency modulation duration reaches 45s.

[0048] The power contribution calculation module includes: the calculation of the actual load change ΔP(t) of primary frequency regulation, the calculation of the theoretical load change ΔP(Δf,t) of primary frequency regulation, and the calculation of the power contribution index of primary frequency regulation, all calculated in accordance with the requirements of national industry standards and specifications.

[0049] When a frequency regulation operation occurs, the absolute value of the actual load contribution is greater than the theoretical value set by the frequency regulation. The prediction is achieved by the ratio of the actual load change ΔP(t) to the theoretical load change ΔP(Δf,t) under different frequency difference conditions, which is used to determine the optimal reset command trigger time.

[0050] The intelligent interlocking control method for primary frequency regulation of supercritical generator sets in this invention is also characterized by:

[0051] For reset condition five, if the power contribution index exceeds the 90% limit after 45 seconds of frequency modulation, the lockout reset is determined by the power contribution index comparator comparing the 45-second power contribution index value with the 90% set value.

[0052] The intelligent interlocking control method for primary frequency regulation of supercritical generator sets in this invention is also characterized by:

[0053] For reset condition six, where the main steam pressure deviation exceeds the set value, the lockout reset is determined by the pressure deviation threshold limiter based on the main steam pressure deviation value. Specifically, the pressure deviation threshold limiter is set with a first threshold value of ±1 MPa and a second threshold value of ±1.5 MPa. When the main steam pressure deviation value exceeds ±1.5 MPa, the pressure deviation threshold limiter outputs a reset command. When the pressure deviation value returns to within ±1 MPa, the pressure deviation threshold limiter releases the reset command.

[0054] Compared with existing technologies, the beneficial effects of this invention are reflected in:

[0055] This invention, through intelligent interlocking control, not only ensures the priority of primary frequency regulation when frequency disturbances occur in the power grid, but also effectively prevents AGC commands from being blocked for a long time, affecting the normal regulation of AGC and causing the unit to disturb the power grid frequency again. This ensures that the primary frequency regulation performance and AGC performance of the generator unit meet the requirements for rapid response to changes in the power grid. Attached Figure Description

[0056] Figure 1 This is a schematic diagram of the control logic relationship of the method of the present invention;

[0057] Figure 2 This is a schematic diagram of the interlocking trigger circuit logic of the present invention;

[0058] Figure 3 This is a schematic diagram of the frequency difference protection circuit logic of the present invention;

[0059] Figure 4 This is a schematic diagram of the logic relationship of the boiler protection circuit of the present invention;

[0060] Figure 5 This is a schematic diagram of the logic relationship of the interlocking recovery loop of the present invention; Detailed Implementation

[0061] See Figure 1 In this embodiment, the intelligent interlocking control method for primary frequency regulation of the supercritical generator unit is as follows: a turbine control interlocking command 2 is issued according to the primary frequency regulation interlocking trigger command 1; and a coal feeding control interlocking command 3 is issued when both the frequency difference protection command 4 and the boiler protection command 5 are triggered; when the primary frequency regulation response contribution power meets the frequency change requirements, an interlocking recovery command 6 is issued by the interlocking recovery circuit 12 to realize intelligent interlocking control; this not only ensures the priority of primary frequency regulation, but also prevents the AGC command from being blocked for a long time, affecting the normal regulation of AGC and causing the unit to disturb the grid frequency again.

[0062] like Figure 1As shown, the interlock trigger command 1 is obtained by the interlock trigger circuit 7 based on the unit control mode 13, main steam pressure 14 and grid frequency 15; the unit control mode 13 is obtained by the AND controller 25 based on the unit's CCS mode, primary frequency regulation activation and switching switch signals.

[0063] The turbine control lockout command 2 is obtained by the turbine control loop 10 after judging the lockout trigger command 1.

[0064] The coal feeding control interlock command 3 is obtained by the coal feeding control circuit 11 when the frequency difference protection command 4, the boiler protection command 5, and the interlock trigger command 1 are all triggered; the frequency difference protection command 4 is obtained by the frequency difference protection circuit 8 based on the power grid frequency 15; the boiler protection command 5 is obtained by the boiler protection circuit 9 based on the furnace pressure 41, the main steam temperature 16, and the main steam pressure 14.

[0065] The interlock recovery command 6 is obtained by the interlock recovery circuit 12 based on the status of the unit load 55, main steam pressure 14, grid frequency 15 and manual reset button 17.

[0066] When the conditions of the primary frequency regulation interlocking trigger circuit 7 are met, the primary frequency regulation interlocks the turbine control circuit 10 according to the grid frequency disturbance; and when both the frequency difference protection command 4 and the boiler protection command 5 are triggered, the coal feeding control circuit 11 is interlocked. The interlocking method under different operating conditions effectively ensures the stability of boiler combustion, and the interlocking is reset according to the change in grid frequency disturbance in response to the primary frequency regulation, so as to realize intelligent interlocking control.

[0067] like Figure 1 As shown, intelligent interlocking control includes interlocking control and interlocking recovery.

[0068] Implement interlocking control as follows:

[0069] For the interlocking control of the turbine control loop 10: the interlocking trigger loop 7 judges the acquired unit control mode 13, main steam pressure 14 and grid frequency 15. If the triggering conditions are met, the interlocking trigger command 1 is output as "1" to the S terminal of RS trigger 19, and the "1" value of the S terminal of RS trigger 19 controls the turbine control loop 10 to be interlocked.

[0070] For the coal feeding control loop 11, the following interlocking control is implemented: To determine whether a primary frequency regulation action requires coal feeding control interlocking, the following judgment conditions are set:

[0071] Condition A: The boiler protection circuit 9 judges the acquired furnace pressure 41, main steam temperature 16 and main steam pressure 14. If the furnace pressure, main steam temperature and main steam pressure are all within the normal range, the boiler protection command 5 is output as "1" to the A1 inter-controller 18.

[0072] Condition B: The frequency difference protection circuit 8 judges the frequency difference value for the acquired power grid frequency 15. If the frequency difference value exceeds the ±0.1Hz large frequency difference judgment limiter, the frequency difference protection command 4 is output as "1" to the A1 inverter 18.

[0073] Condition C: The RS flip-flop 19 sends the "1" value instruction at its S terminal to the A1 AND converter 18;

[0074] When conditions A, B, and C all output a "1" value command to A1 AND controller 18, A1 AND controller 18 outputs a "1" value command to control the coal feeding control loop 11 to lock out.

[0075] Lockout recovery is achieved as follows:

[0076] During the primary frequency regulation interlock control of the unit, the interlock recovery circuit 12 obtains the status of the unit load 55, main steam pressure 14, grid frequency 15, and manual reset button 17. If any condition is met, the interlock recovery command 6 is output to the R terminal of RS trigger 19 to reset the interlock commands of turbine control circuit 10 and coal feeding control circuit 11, thereby realizing the interlock recovery.

[0077] In practice, the corresponding technical measures include:

[0078] See Figure 1 and Figure 2 When the direction of the primary frequency regulation action is opposite to the direction of AGC regulation, and the conditions of the unit's main steam pressure 14 and the unit's control mode 13 are both met, the interlock trigger circuit 7 will trigger the interlock AGC increase command 21 or the interlock AGC decrease command 22 in the following manner:

[0079] If a high-frequency difference disturbance occurs at the grid frequency 15, the blocking trigger circuit 7 outputs the blocking AGC increase command 21 to maintain the unit's AGC load increase command, effectively ensuring that the unit's primary frequency regulation prioritizes response to the grid's high-frequency difference rapid load reduction adjustment, so as to quickly eliminate the grid's high-frequency disturbance and maintain grid frequency stability; the high-frequency difference disturbance is obtained by the high-frequency difference limiter 28 judging the frequency difference value 36, and the high-frequency difference limit is set to +0.0333Hz.

[0080] If a low-frequency difference disturbance occurs at the grid frequency 15, the blocking trigger circuit 7 outputs the blocking AGC reduction command 22 to maintain the unit's AGC load reduction command, effectively ensuring that the unit's primary frequency regulation prioritizes the response to the grid's low-frequency difference rapid load increase adjustment, so as to quickly eliminate the grid's low-frequency disturbance and maintain grid frequency stability; the low-frequency difference disturbance is obtained by judging the frequency difference value 36 through the low-frequency difference limiter 27, and the low-frequency difference limit is set to -0.0333Hz.

[0081] Figure 2 The high-frequency difference limiter 28 shown is used to determine whether the frequency difference value exceeds the frequency regulation dead zone of +0.0333Hz, resulting in a high-frequency disturbance signal from the power grid. The input of the high-frequency difference limiter 28 is the frequency difference value 36 and the rated frequency difference of +0.0333Hz, and its output is the high-frequency disturbance signal from the power grid, which is connected to the input of A5 AND converter 23. The input of A4 AND converter 25 is connected to the switching switch, CCS control mode, and primary frequency regulation activation, respectively, to determine whether the unit control mode conditions are met. The output of A4 AND converter 25 is connected to the input of A5 AND converter 23. The input terminals of the main steam pressure deviation calculation module 31 are connected to the main steam pressure 14 and the pressure setpoint, respectively, and are used to calculate the main steam pressure deviation value. The pressure deviation low / high judgment unit 30 is used to judge whether the main steam pressure deviation value is too low / too high. The N1 negator 26 inverts the output value of the pressure deviation low / high judgment unit 30 and is used to judge whether the main steam pressure regulation is within the normal range. The output of the N1 negator 26 is connected to the input terminal of the A5 AND value unit 23, and the A5 AND value unit 23 outputs the trigger lockout AGC increment command 21.

[0082] Figure 2 The low-frequency difference limiter shown is used to determine whether the frequency difference value exceeds the frequency modulation dead zone of -0.0333Hz and a low-frequency disturbance signal of the power grid occurs. The input of the low-frequency difference limiter 27 is the frequency difference value 36 and the rated frequency difference of -0.0333Hz. Its output is the low-frequency disturbance signal of the power grid connected to the input of A6 AND limiter 24. The input of A6 AND limiter 24 is also connected to the output of A4 AND limiter 25 and the output of N1 NOTer 26. A6 AND limiter 24 outputs the AGC decrement command 22.

[0083] Whether the condition of main steam pressure 14 is met is determined by the calculated main steam pressure deviation value 37 after the pressure deviation too low / too high judgment device 30 judges it, and then by the N1 negator 26. The output of the N1 negator 26 is connected to one input terminal of the A5 AND device 23. The main steam pressure deviation value 37 is calculated by the main steam pressure deviation calculation module 31 based on the main steam pressure 14 and the pressure set value.

[0084] See Figure 1 and Figure 3The frequency difference protection circuit 8 includes a frequency difference calculation module 29, a frequency modulation dead zone limiter 40, and an A2 AND converter 32. The input of the frequency difference calculation module 29 is the grid frequency 15Hz and the rated frequency 50Hz, and the output is the frequency difference value 36. The frequency modulation dead zone limiter 40 is used to determine whether the grid frequency difference value exceeds the frequency modulation dead zone and outputs a primary frequency modulation action signal. The output of the frequency modulation dead zone limiter 40 is connected to the input of the A2 AND converter 32. The frequency difference protection circuit 8 also includes an RS flip-flop 33, a T1 timer 34, and a large frequency difference limiter 35. The large frequency difference limiter 35 is used to determine whether the grid frequency difference value exceeds the large frequency difference limit. Its output is connected to the S terminal of the RS flip-flop 33. The output of the S terminal of the RS flip-flop 33 is connected to the input of the A2 AND converter 32, and the A2 AND converter 32 outputs the frequency difference protection command 4. In specific implementation, the limit value of the large frequency difference limiter 35 is set to ±0.1Hz. The reset signal of the R terminal of the RS flip-flop 33 is obtained by the timing judgment of the T1 timer 34. The T1 timer 34 is used to time the duration of the output of the large frequency difference limiter 35. The output of the T1 timer 34 is connected to the R terminal of the RS flip-flop 33 to reset the S terminal output. The timing duration of the T1 timer 34 is set to 50s.

[0085] Frequency difference protection circuit 8 implements frequency difference protection as follows:

[0086] When a disturbance occurs at the grid frequency 15, if the calculated frequency difference value 36 exceeds the ±0.0333Hz frequency dead zone limiter 40, a frequency regulation action signal is output. At the same time, the large frequency difference limiter 35 determines whether the grid frequency disturbance is a large frequency difference disturbance. If it is not a large frequency difference disturbance, the S terminal of the RS flip-flop 33 outputs a value of "0" and the frequency difference protection command 4 is not triggered. If it is a large frequency difference disturbance, the S terminal of the RS flip-flop 33 outputs a value of "1", triggering the frequency difference protection command 4. The protection duration is set by the T1 timer 34. When the timer reaches the protection duration, the S terminal output of the RS flip-flop 33 is reset to avoid the frequency difference protection command 4 from causing disturbance to the unit regulation due to an excessively long duration. The frequency difference value 36 is calculated by the frequency difference calculation module 29 for the grid frequency 15 and the rated frequency of 50Hz.

[0087] See Figure 1 and Figure 4 Boiler protection circuit 9 implements boiler protection in the following manner:

[0088] like Figure 1 As shown, during unit operation, when the main steam pressure 14, furnace pressure 41 and main steam temperature 16 are all under normal operating conditions, a boiler protection command 5 is generated. This command serves as a condition for determining whether the boiler coal feeding control circuit is locked when the unit responds to the primary frequency regulation action. It is used to protect the boiler control from secondary disturbances caused by the response to the primary frequency regulation action.

[0089] like Figure 4 As shown, the normal operating conditions of furnace pressure 41 include that the pressure value adjustment of furnace pressure 41 does not exceed the limit, and the rate of change of furnace pressure 41 is normal. Specifically, the furnace pressure 41's pressure value adjustment not exceeding the limit is determined by the furnace pressure over / under pressure detector 46 based on the furnace pressure 41, and then obtained through the H1 NOR device 44. Whether the rate of change of furnace pressure 41 is normal is determined by the rise / fall rate detector 45 based on the furnace pressure deviation value 38, and then obtained through the H1 NOR device 44. In specific implementation, the furnace pressure deviation value 38 is calculated by the furnace pressure deviation calculation module 47 based on the furnace pressure 41's pressure value, and is calculated per second as the furnace pressure change. The pressure value is recorded by the pressure hysteresis controller 48 for the furnace pressure 41 to obtain the pressure value of the furnace pressure one second ago. The input of the pressure hysteresis controller 48 is connected to the furnace pressure 41, and its output is connected to the input of the furnace pressure deviation calculation module 47. The furnace pressure deviation calculation module 47 is used to calculate the difference in furnace pressure change per second. The input of the furnace pressure deviation calculation module is also connected to the furnace pressure 41. The output of the furnace pressure deviation calculation module 47 is connected to the input of the rise / fall rate judge 45. The rise / fall rate judge 45 judges whether the instantaneous change of furnace pressure is too fast. The output of the rise / fall rate judge 45 is connected to the input of the H1 NOR device 44. Figure 4 As shown, the pressure over / under pressure detector 46 is used to determine whether the furnace pressure value is too high or too low. Its output is connected to the input of the H1 NOR device 44, which is used to determine whether the furnace pressure value is within the normal adjustment range.

[0090] like Figure 4 As shown, the normal operating conditions of the main steam temperature 16 include that the temperature value of the main steam temperature 16 is not exceeded and the rate of change of the main steam temperature 16 is normal. Among them, the temperature value of the main steam temperature 16 is not exceeded by judging the temperature value of the main steam temperature 16 through the main steam temperature too high / too low judge 52, and then through the judgment of the H2 NOR device 50. The main steam temperature too high / too low judge 52 is used to judge whether the main steam temperature value is too high or too low. Its output is connected to the input terminal of the H2 NOR device 50. The H2 NOR device 50 is used to judge whether the main steam temperature is within the normal adjustment range.

[0091] Whether the rate of change of the main steam temperature 16 is normal is determined by judging the main steam temperature deviation value 39 by the rate of decrease judgment 51, and then by the H2 NOR device 50. In specific implementation, the main steam temperature deviation value 39 is the rate of change of the main steam temperature per second calculated by the main steam temperature deviation calculation module 53 based on the temperature value of the main steam temperature 16. The temperature value is recorded by the temperature lag controller 54 based on the temperature value of the main steam temperature 16 to obtain the temperature value of the main steam temperature one second ago. The input of the temperature lag controller 54 is connected to the main steam temperature 16, and its output is connected to the input of the main steam temperature deviation calculation module 53. The main steam temperature deviation calculation module 53 is used to calculate the main steam temperature deviation value. The difference in steam temperature before and after is calculated. The input of the main steam temperature deviation calculation module 53 is also connected to the main steam temperature 16. The output of the main steam temperature deviation calculation module 53 is connected to the input of the descent rate judge 51. The descent rate judge 51 is used to determine whether the instantaneous change in main steam temperature is too fast. The output of the descent rate judge 51 is connected to the input of the H2 NOR device 50. The N1 NOR device 26 is set to determine whether the main steam pressure value is within the normal adjustment range. The output of the N1 NOR device 26 is connected to the input of the A3 AND device 42. The outputs of the H1 NOR device 44 and the H2 NOR device 50 are both connected to the input of the A3 AND device 42. The A3 AND device 42 outputs the boiler protection command 5.

[0092] See Figure 5 Lockout recovery is performed immediately when any of the following conditions are met, so that the unit can not only ensure that the primary frequency regulation contribution meets the grid frequency disturbance requirements in real time under any operating condition, but also prevent the unit from disturbing the grid frequency again due to the long-term lockout of AGC commands affecting the normal regulation of AGC.

[0093] Condition 1: Manual reset is triggered by manual reset button 17, which manually sends a lockout recovery command 6 to the lockout recovery circuit 12. Figure 5 The manual reset button 17 shown is connected to the input terminal of O3 or value generator 56.

[0094] Condition 2: Frequency difference value returns to frequency modulation dead zone reset. Set frequency modulation dead zone limiter 40 to determine whether the grid frequency difference value exceeds the frequency modulation dead zone ±0.0333Hz; set N2 NOT device 59 to determine whether the frequency difference value returns to the frequency modulation dead zone. If the frequency difference value returns to the frequency modulation dead zone, lockout reset. Figure 5 The output of the frequency modulation dead zone limiter 40 is connected to the input of the N2 negation unit 59. The N2 negation unit 59 is used to determine whether the frequency difference value has returned to the frequency modulation dead zone. The output signal of the N2 negation unit 59 is connected to the input of the O3 or valuer 56.

[0095] Condition 3: Time limit reset. The T2 timer 60 is used to time the duration of the output of the frequency dead zone limiter 40. To prevent the AGC command from being locked out for an extended period, thus affecting normal AGC regulation, and considering the grid's requirements for the primary frequency regulation response time of the generator set, the set duration of the T2 timer 60 is set to 60 seconds. The output of the T2 timer 60 is connected to the input of O3 or the value setter 56. If the primary frequency regulation duration exceeds the set duration, the lockout is reset. This satisfies both the grid's requirements for the primary frequency regulation response time of the generator set and prevents the AGC command from being locked out for an extended period, thus affecting normal AGC regulation.

[0096] Condition 4: When the actual load contribution is greater than the theoretical value of the frequency regulation setting during a single frequency regulation operation, the lockout is reset.

[0097] Condition 5: If the power contribution index of frequency modulation operation exceeds 90% for 45 seconds, the lockout will be reset.

[0098] Condition 6: If the main steam pressure deviation is greater than the set value, the interlock will be reset.

[0099] In specific implementation, such as Figure 5 As shown, for condition 4, when the absolute value of the actual load contribution is greater than the theoretical value of the frequency regulation setting during the first frequency regulation action, the lockout reset is obtained by the overshoot prediction circuit 75 and the undershoot prediction circuit 76.

[0100] Figure 5 The overshoot prediction loop 75 shown includes: a D1 divider 71, the actual load change output by the power contribution calculation module 69 is input to the D1 divider 71, the theoretical load change output by the power contribution calculation module 69 is output by the f(x1) function generator 67 to generate the expected overshoot frequency modulation contribution, and is input to the D1 divider 71, the D1 divider 71 calculates the overshoot ratio of the actual load change to the expected overshoot frequency modulation contribution, and the overshoot ratio is judged by the overshoot judge 63 to obtain the overshoot prediction signal.

[0101] In practice Figure 5 The input terminal of the power contribution calculation module 69 shown is connected to the grid frequency 15 and the unit load 55. Its output actual load change ΔP(t) and theoretical load change ΔP(Δf,t) are connected to the input terminal of the overshoot prediction circuit 75. The overshoot prediction circuit 75 is used to determine whether the absolute value of the actual load contribution is greater than the theoretical value of frequency regulation by a certain margin. Its output is connected to the S terminal of RS flip-flop 58. RS flip-flop 58 is used to trigger the reset command. It is triggered when the S terminal of RS flip-flop 58 is "1" and not triggered when the R terminal is "1". The output of RS flip-flop 58 is connected to the input terminal of O3 or valuer 56.

[0102] Figure 5The under-adjustment prediction loop 76 shown includes: a D2 divider 72, the actual load change output by the power contribution calculation module 69 is input to the D2 divider 72, the theoretical load change output by the power contribution calculation module 69 is output by the f(x2) function generator 68 to generate the under-adjustment expected frequency modulation contribution, and is input to the D2 divider 72, the D2 divider 72 calculates the ratio of the actual load change to the under-adjustment expected frequency modulation contribution, and the under-adjustment ratio is judged by the under-adjustment judge 64 to obtain the under-adjustment prediction signal.

[0103] The power contribution calculation module 69 includes: the calculation of the actual load change ΔP(t) of primary frequency regulation, the calculation of the theoretical load change ΔP(Δf,t) of primary frequency regulation, and the calculation of the power contribution index of primary frequency regulation, all calculated in accordance with the requirements of national industry standards and specifications; the judgment values ​​of the overshoot judge 63 and the undershoot judge 64 are both set to "1".

[0104] When the absolute value of the actual load contribution is greater than the theoretical value set during a frequency regulation operation, the ratio of the actual load change ΔP(t) to the theoretical load change ΔP(Δf,t) under different frequency difference conditions is used to predict and determine the optimal reset command trigger time.

[0105] In specific implementation, the input signal of the f(x1) function generator 67 is the theoretical load change ΔP(Δf,t), and the output is the expected frequency modulation contribution ΔP(Δf,t)'. The expected frequency modulation contribution ΔP(Δf,t)' is connected to one input terminal of the D1 divider 71. The f(x1) function is a nonlinear function. The f(x1) function generator 67 is used to calculate the expected frequency modulation contribution ΔP(Δf,t)' of the theoretical load change ΔP(Δf,t) under different frequency differences. When the absolute value of the frequency difference is larger, the value of the frequency modulation contribution ΔP(Δf,t)' is smaller. The other input terminal of the D1 divider 71 is the actual load change ΔP(t). The output of the D1 divider 71 is... The output terminal is connected to the input terminal of the overshoot detector 63; the D1 divider 71 is used to calculate the ratio of the actual load change ΔP(t) to the expected frequency modulation contribution ΔP(Δf,t)'. The ratio represents the multiple of the actual load change ΔP(t) to the expected frequency modulation contribution ΔP(Δf,t)' under different frequency differences. If the actual load change ΔP(t) is greater than the frequency modulation contribution ΔP(Δf,t)' under different frequency differences, that is, the ratio ΔP(t) / ΔP(Δf,t)'>1, it indicates that the primary frequency modulation response has an overshoot phenomenon; the overshoot detector 63 is set to "1", and the ratio of the D1 divider 71 is determined to be several times the value of "1" under different frequency differences, thereby outputting a lockout reset signal.

[0106] In specific implementation, the output of the f(x2) function generator 68 is the theoretical load change ΔP(Δf,t), and the output is the expected frequency modulation contribution ΔP(Δf,t)”. The expected frequency modulation contribution ΔP(Δf,t)” is connected to one input of the D2 divider 72. The f(x2) function is a nonlinear function. The f(x2) function generator 68 is used to calculate the expected frequency modulation contribution ΔP(Δf,t)” of the theoretical load change ΔP(Δf,t) under different frequency differences. When the absolute value of the frequency difference is larger, the value of the expected frequency modulation contribution ΔP(Δf,t)” is smaller. The other input of the D2 divider 72 is the actual load change ΔP(t). The output of divider 72 is connected to the input of under-adjustment judgment unit 64. Divider 72 is used to calculate the ratio of the actual load change ΔP(t) to the expected frequency modulation contribution ΔP(Δf,t)”. The ratio represents the multiple of the actual load change ΔP(t) to the expected frequency modulation contribution ΔP(Δf,t)” under different frequency differences. If the actual load change ΔP(t) is less than the expected frequency modulation contribution ΔP(Δf,t)” under different frequency differences, that is, the ratio ΔP(t) / ΔP(Δf,t)” is less than 1, it indicates that the primary frequency modulation response has an under-adjustment phenomenon. The under-adjustment judgment unit 64 is set to "1" and the ratio of divider 72 is determined to be no greater than the value of "1".

[0107] This invention predicts and judges the ratio of the actual load change ΔP(t) to the theoretical load change ΔP(Δf,t)' under different frequency difference operating conditions. When the absolute value of the frequency difference is larger, the actual load change ΔP(t) can be adjusted less to prevent excessive overshoot of the actual load in the later stage of frequency regulation, which would cause oscillations in AGC regulation. When the absolute value of the frequency difference is smaller, the actual load change ΔP(t) can be adjusted more to ensure that the unit's primary frequency regulation contribution meets the primary frequency regulation index. At the same time, when the contribution of the actual load change ΔP(t) is insufficient, the trigger command is blocked to further ensure the unit's primary frequency regulation contribution.

[0108] The optimal reset command trigger time for the under-adjustment prediction loop 76 is determined by the T3 timer 66 based on whether the frequency regulation duration reaches 45s. If the under-adjustment prediction loop 76 outputs a "1" value, it indicates that the actual load change ΔP(t) contribution of the primary frequency regulation is insufficient. The output of the under-adjustment prediction loop 76 is connected to the input terminal of the A7 AND converter 61. The output of the T3 timer 66 is connected to the input terminal of the N3 NOT converter 62. The N3 NOT converter 62 is used to determine whether the frequency regulation duration output by the T3 timer 66 has reached 45s. If it has not reached 45s, the N3 NOT converter 62 outputs a "1" value. The output of the N3 NOT converter 62 is connected to the other input terminal of the A7 AND converter 61. The output of the A7 AND converter 61 is connected to the R terminal of the RS flip-flop 58. When the primary frequency regulation is activated, if the actual load change ΔP(t) contribution of the primary frequency regulation is insufficient and the frequency regulation duration is less than 45s, the lockout command is not reset, further ensuring the primary frequency regulation contribution of the unit.

[0109] like Figure 5 As shown, for condition five, if the power contribution index exceeds the 90% limit after a 45-second frequency adjustment action, the lockout reset is determined by the power contribution index comparator 65 based on the 45-second power contribution index 70 and the 90% setpoint. The 45-second power contribution index 70 is calculated by the power contribution calculation module 69 based on the grid frequency 15 and the unit load 55. The output of the power contribution calculation module 69 is connected to the input of the power contribution index comparator 65, which compares whether the 45-second power contribution index exceeds the 90% limit. The output of the power contribution index comparator 65 is connected to the input of O3 or valuer 56.

[0110] like Figure 5 As shown, for condition six where the main steam pressure deviation exceeds the set value, the lockout reset is determined by the pressure deviation threshold limiter 57 based on the main steam pressure deviation value 37. Specifically, the pressure deviation threshold limiter 57 is set with a first threshold value of ±1 MPa and a second threshold value of ±1.5 MPa. When the main steam pressure deviation value exceeds ±1.5 MPa, the pressure deviation threshold limiter 57 outputs a reset command; when the pressure deviation value returns to within ±1 MPa, the pressure deviation threshold limiter 57 releases the reset command.

[0111] In practice: the actual load change ΔP(t) of primary frequency regulation is calculated using equation (1):

[0112] ΔP(t)=PSt-PST (1)

[0113] In formula (1):

[0114] PST represents the actual unit load of the generator set at time t0 when the primary frequency regulation begins; PST represents the load of the generator set after time t0. 调节The actual load of the unit within the specified time period; the integral energy △QsY actually calculated for the primary frequency regulation of the unit is:

[0115]

[0116] in:

[0117] t0 is the moment when the power grid frequency equals 50 ± 0.033.

[0118] t 调节 For the time when the power grid frequency exceeds 50 ± 0.033, t 调节 The maximum value is 60 seconds;

[0119] The theoretical load change ΔP(Δf,t) is calculated using equation (2):

[0120]

[0121] in:

[0122] △f(t) represents the amount by which the power grid frequency exceeds 50±0.033 at time t;

[0123] △n(t) represents the amount by which the rotational speed exceeds 3000±2 at time t, with positive values ​​for high frequencies and negative values ​​for low frequencies;

[0124] δ% is the unit droop coefficient; MCR is the unit's rated active power output.

[0125] The integral energy ΔQjY of the unit's primary frequency regulation theoretical calculation is obtained from equation (3):

[0126]

[0127] The primary frequency regulation power contribution index DX is calculated using equation (4):

[0128]

[0129] Analysis of primary frequency regulation data from multiple supercritical units shows that when the 45-second power contribution index reaches 90%, the 60-second power contribution index can usually reach over 60%, meeting the primary frequency regulation performance requirements. Therefore, the 45-second power contribution index is used for comparison in this invention.

Claims

1. A method for intelligent interlocking control of primary frequency regulation in a supercritical generator set, characterized by: According to the primary frequency regulation interlock trigger command (1), the turbine control interlock command (2) is issued; and when both the frequency difference protection command (4) and the boiler protection command (5) are triggered, the coal feeding control interlock command (3) is issued; when the primary frequency regulation response contribution power meets the frequency change requirements, the interlock recovery circuit (12) issues the interlock recovery command (6) to realize intelligent interlock control; The interlock trigger command (1) is obtained by the interlock trigger circuit (7) based on the unit control mode (13), main steam pressure (14), and grid frequency (15); the unit control mode (13) is obtained by the AND gate (25) based on the unit's CCS mode, primary frequency regulation activation, and switching signals; the turbine control interlock command (2) is obtained by the turbine control circuit (10) based on the interlock trigger command (1); the coal feed control interlock command (3) is obtained by the coal feed control circuit (11) when the frequency difference protection command (4), boiler protection command (5), and interlock trigger command (1) are all triggered; the frequency difference protection command (4) is obtained by the frequency difference protection circuit (8) based on the unit control mode (13), main steam pressure (14), and grid frequency (15). The power grid frequency (15) is obtained by judgment; the boiler protection command (5) is obtained by the boiler protection circuit (9) based on the furnace pressure (41), main steam temperature (16) and main steam pressure (14); the lockout recovery command (6) is obtained by the lockout recovery circuit (12) based on the unit load (55), main steam pressure (14), power grid frequency (15) and the status of the manual reset button (17); when the lockout trigger circuit (7) of the unit primary frequency regulation meets the conditions, the primary frequency regulation performs lockout control on the turbine control circuit (10) according to the power grid frequency disturbance; and when both the frequency difference protection command (4) and the boiler protection command (5) are triggered, the coal feeding control circuit (11) is lockedout controlled; The intelligent interlocking control includes interlocking control and interlocking recovery: The interlocking control is implemented as follows: Turbine control circuit (10) interlocking control: The interlocking trigger circuit (7) judges the acquired unit control mode (13), main steam pressure (14) and grid frequency (15). If the triggering conditions are met, the interlocking trigger command (1) is output as "1" to the S terminal of the first RS trigger (19), and the interlocking control circuit (10) is controlled by the "1" value command of the S terminal of the first RS trigger (19). Coal feeding control loop (11) interlock control: Set the following judgment conditions: Condition A, the boiler protection loop (9) judges the furnace pressure (41), main steam temperature (16) and main steam pressure (14) obtained. If the furnace pressure, main steam temperature and main steam pressure are all within the normal range, the boiler protection command (5) is output as "1" to the A1 inverter (18); Condition B, the frequency difference protection loop (8) judges the frequency difference of the obtained power grid frequency (15). If the frequency difference exceeds the ±0.1Hz large frequency difference judgment limiter, the frequency difference protection command (4) is output as "1" to the A1 AND converter (18); under condition C, the first RS trigger (19) sends the "1" value command of its S terminal to the A1 AND converter (18); when conditions A, B and C all output "1" value commands to the A1 AND converter (18), the A1 AND converter (18) outputs "1" value commands to control the coal feeding control circuit (11) to lock out; The lockout is restored as follows: During the primary frequency regulation lockout control of the unit, the lockout restoration circuit (12) obtains the status of the unit load (55), main steam pressure (14), grid frequency (15) and manual reset button (17). If any condition is met, the lockout restoration command (6) is output to the R terminal of the first RS trigger (19) to reset the lockout command of the turbine control circuit (10) and the coal feeding control circuit (11) to realize the lockout restoration.

2. The intelligent interlocking control method for primary frequency regulation of a supercritical generator set according to claim 1, characterized in that: When the direction of the frequency regulation action is opposite to the direction of AGC regulation, and the conditions of the unit's main steam pressure (14) and the unit's control mode (13) are met, the interlock trigger circuit (7) triggers the interlock AGC increase command (21) or the interlock AGC decrease command (22) in the following manner: If a high-frequency difference disturbance occurs in the grid frequency (15), the interlock trigger circuit (7) outputs the interlock AGC increase command (21) to maintain the unit's AGC load increase command; the high-frequency difference disturbance is determined by the high-frequency difference limiter (28) based on the frequency difference value (36), and the high-frequency difference is determined by the limiter. The difference limit is set to +0.0333Hz; if a low frequency difference disturbance occurs in the grid frequency (15), the blocking trigger circuit (7) outputs the blocking AGC reduction command (22) to keep the unit AGC load reduction command; the low frequency difference disturbance is obtained by the low frequency difference limiter (27) judging the frequency difference value (36), and the low frequency difference limit is set to -0.0333Hz; the condition of the main steam pressure (14) is met by judging the main steam pressure deviation value (37) by the pressure deviation too high / too low judgment device (30), and then judging it by the N1 negator (26).

3. The intelligent interlocking control method for primary frequency regulation of a supercritical generator set according to claim 1, characterized in that: The frequency difference protection circuit (8) implements frequency difference protection in the following manner: when the grid frequency (15) is disturbed, if the frequency difference value (36) exceeds the frequency dead zone limiter (40) of ±0.0333Hz, a frequency regulation action signal is output. At the same time, the large frequency difference limiter (35) determines whether the grid frequency disturbance has a large frequency difference disturbance. If it is not a large frequency difference disturbance, the S terminal of the second RS flip-flop (33) outputs a value of "0" and does not trigger the frequency difference protection command (4). If it is a large frequency difference disturbance, the S terminal of the second RS flip-flop (33) outputs a value of "1" and triggers the frequency difference protection command (4). The protection duration is set by the T1 timer (34). When the timer reaches the protection duration, the S terminal output of the second RS flip-flop (33) is reset to avoid the frequency difference protection command (4) from causing disturbance to the unit regulation due to the excessive duration.

4. The intelligent interlocking control method for primary frequency regulation of a supercritical generator set according to claim 1, characterized in that: The boiler protection circuit (9) implements boiler protection in the following manner: During unit operation, when the main steam pressure (14), furnace pressure (41), and main steam temperature (16) are all under normal operating conditions, a boiler protection command (5) is generated, which serves as the judgment condition for whether the boiler coal feeding control circuit is locked when the unit responds to the primary frequency regulation action; the normal operating conditions of the furnace pressure (41) include that the pressure value regulation of the furnace pressure (41) does not exceed the limit, and the rate of change of the furnace pressure (41) is normal; wherein: the pressure value regulation of the furnace pressure (41) does not exceed the limit is judged by the furnace pressure too high / too low judgment device (46) for the furnace pressure (41), and then obtained by the H1 NOR device (44); the rate of change of the furnace pressure (41) Normal operation is determined by the rise / fall rate judge (45) based on the furnace pressure deviation value (38), and then by the H1 OR device (44); the normal operating condition of the main steam temperature (16) includes that the temperature value adjustment of the main steam temperature (16) does not exceed the limit, and the change rate of the main steam temperature (16) is normal; wherein, the temperature value adjustment of the main steam temperature (16) does not exceed the limit is obtained by judging the temperature value of the main steam temperature (16) by the main steam temperature too high / too low judge (52), and then by the H2 OR device (50); the normal change rate of the main steam temperature (16) is obtained by judging the main steam temperature deviation value (39) by the fall rate judge (51), and then by the H2 OR device (50).

5. The intelligent interlocking control method for primary frequency regulation of a supercritical generator set according to claim 1, characterized in that: The lockout restoration is performed when any of the following conditions are met: Condition 1: Manual reset, the lockout recovery circuit (12) is manually triggered by the manual reset button (17) to issue the lockout recovery command (6); Condition 2: Frequency difference value returns to frequency modulation dead zone reset, set frequency modulation dead zone limiter (40) to determine whether the grid frequency difference value exceeds the frequency modulation dead zone ±0.0333Hz; set N2 NOT device (59) to determine whether the frequency difference value returns to the frequency modulation dead zone. If the frequency difference value returns to the frequency modulation dead zone, lockout reset. Condition 3: Time limit reset. The T2 timer (60) is used to time the duration of the output of the frequency modulation dead zone limiter (40). If the duration of a frequency modulation exceeds the set duration, the lockout is reset. Condition 4: If the absolute value of the actual load contribution is greater than the theoretical value set for frequency regulation, the lockout will be reset. Condition 5: If the power contribution index of frequency modulation operation exceeds 90% for 45 seconds, the lockout will be reset. Condition 6: If the main steam pressure deviation is greater than the set value, the interlock will be reset.

6. The intelligent interlocking control method for primary frequency regulation of a supercritical generator set according to claim 5, characterized in that: For reset condition four, where the absolute value of the actual load contribution is greater than the set amplitude of the frequency regulation theoretical value, the lockout reset is determined by the overshoot prediction circuit (75) and the undershoot prediction circuit (76); where: The overshoot prediction loop (75) includes: setting up a D1 divider (71), the actual load change output by the power contribution calculation module (69) is connected to the D1 divider (71), the theoretical load change output by the power contribution calculation module (69) is output by the f(x1) function generator (67) as the expected frequency modulation contribution of overshoot, and connected to the D1 divider (71), the overshoot ratio of the actual load change to the expected frequency modulation contribution of overshoot is calculated by the D1 divider (71), and the overshoot ratio is judged by the overshoot judge (63) to obtain the overshoot prediction signal; The under-adjustment prediction loop (76) includes: setting up a D2 divider (72), the actual load change output by the power contribution calculation module (69) is connected to the D2 divider (72), the theoretical load change output by the power contribution calculation module (69) is output by the f(x2) function generator (68) as the under-adjustment expected frequency modulation contribution, and connected to the D2 divider (72), the ratio of the actual load change to the under-adjustment expected frequency modulation contribution is calculated by the D2 divider (72), and the under-adjustment ratio is judged by the under-adjustment judge (64) to obtain the under-adjustment prediction signal; The optimal reset command trigger time of the under-adjustment prediction circuit (76) is determined by timer T3 (66) based on whether the frequency modulation duration reaches 45s. The power contribution calculation module (69) includes: actual load change of primary frequency regulation. The calculation of the theoretical load change of primary frequency regulation. The calculation of the power contribution index of primary frequency regulation; When a frequency regulation operation occurs, the absolute value of the actual load contribution exceeds the theoretical frequency regulation setting range. This is measured by the actual load change under different frequency difference conditions. and theoretical load change The ratio is used to predict and determine the optimal timing for triggering the reset instruction.

7. The intelligent interlocking control method for primary frequency regulation of a supercritical generator set according to claim 5, characterized in that: For reset condition five, the power contribution index of the frequency modulation action lasting 45s exceeds the 90% limit, and the lockout reset is obtained by the power contribution index comparator (65) comparing the 45s power contribution index value with the 90% set value.

8. The intelligent interlocking control method for primary frequency regulation of a supercritical generator set according to claim 5, characterized in that: For reset condition six, the main steam pressure deviation is greater than the set value. The lockout reset is obtained by the pressure deviation threshold limiter (57) judging the main steam pressure deviation value (37). In the pressure deviation threshold limiter (57), a first threshold value of ±1 MPa and a second threshold value of ±1.5 MPa are set respectively. When the main steam pressure deviation value exceeds ±1.5 MPa, the pressure deviation threshold limiter (57) outputs a reset command. When the pressure deviation value returns to within ±1 MPa, the pressure deviation threshold limiter (57) releases the reset command.

Images