CN110571833B

CN110571833B - Primary frequency modulation control device of thermal power generating unit based on flywheel energy storage

Info

Publication number: CN110571833B
Application number: CN201910891940.7A
Authority: CN
Inventors: 李军; 高嵩; 王昕�; 孟祥荣; 李巍巍; 李�杰; 张用; 秦怡鸣; 庞向坤; 路宽; 姚常青; 孙萌萌
Original assignee: Electric Power Research Institute of State Grid Shandong Electric Power Co Ltd
Current assignee: Electric Power Research Institute of State Grid Shandong Electric Power Co Ltd
Priority date: 2019-09-20
Filing date: 2019-09-20
Publication date: 2021-03-19
Anticipated expiration: 2039-09-20
Also published as: CN110571833A

Abstract

The invention provides a primary frequency modulation control method and device of a thermal power generating unit based on flywheel energy storage_F‑RatedAnd real-time power value P_F‑ActualCalculating the power value which can be released and absorbed by the flywheel energy storage device, and dynamically judging and distributing the power variation delta P required to be provided by the unit in the primary frequency modulation compensation action according to the actual power regulation capacity of the flywheel energy storage device_UAnd the amount of power change Δ P to be supplied by the flywheel energy storage device_F. According to the invention, the power of the flywheel energy storage device and the primary frequency modulation compensation power demand are monitored and analyzed, the distribution of the frequency modulation increment between the unit and the energy storage device is dynamically allocated, the problem of insufficient work in the early stage of frequency modulation caused by the inherent delay characteristic of the thermal power unit is solved by utilizing the capability of the flywheel energy storage system for rapidly and accurately charging and discharging the power, and the stable operation of a power grid is ensured while the energy storage is effectively utilized and the unit action is reduced.

Description

Primary frequency modulation control device of thermal power generating unit based on flywheel energy storage

Technical Field

The invention relates to the technical field of network source coordination control, in particular to a thermal power generating unit primary frequency modulation control method and device based on flywheel energy storage.

Background

Under the new potential of interconnection of an extra-high voltage power grid and a large-area power grid, the connection of all levels of power grids is gradually tight, and the requirement for coordination between the power grids and a unit is higher and higher. Meanwhile, the new energy installation and the power generation capacity of China are rapidly improved, and the new energy installation (wind power, photovoltaic and nuclear power) accounts for 16% less than 2016 to 18.5% of 2017 at the end of 9 months. By 9 months in 2017, the total installed capacity of new energy reaches 275GW, the installed capacity of the new thermal power is only 33%, the installed capacity of the new energy reaches 58%, 7 million-level wind power bases are built in China in the future, and wind power with total 150GW is merged into each regional power grid in 2020. Meanwhile, the interconnection between the areas is increasingly compact, and the power system faces a large amount of power transfer between the areas and large-scale fluctuation of power flow.

With the development of the power grid structure in China towards large units, high parameters and extra-high voltage, the traditional frequency modulation method can not adapt to the change at present. And the power system is connected with more and more wind power and photovoltaic power generation, the load fluctuation of the system becomes more and more obvious, and the pressure of frequency modulation in the regional power grid is increased. How to ensure the frequency stability, safety and reliability of the power system is one of the problems to be solved urgently in the current china power grid. In recent years, a synchronous vector measurement technology based on a Global Positioning System (GPS) technology is continuously mature and developed, the problem of synchronous acquisition of data at different spatial positions is fundamentally solved, and the synchronous acquisition of unit wide-area measurement information is realized; meanwhile, PMU device distribution and measurement configuration in the power grid jurisdiction range are increasingly perfect and abundant, and a good data base is laid for online monitoring and analysis of the unit primary frequency modulation performance. For the main components and the main frequency modulation of the current Chinese power grid, the primary frequency modulation of the thermal power generating set is mainly realized by adjusting an air inlet adjusting door of a DEH (Digital Electric hydro Control System, steam turbine Digital electro-Hydraulic Control System), utilizing boiler heat storage, quickly responding to the requirement of the power grid when the power grid is abnormal, stabilizing the power grid frequency, and making up the load gap of the power grid, thereby maintaining the safety of the power grid.

At present, an energy storage technology is applied to the field of frequency modulation and peak shaving in the power industry, but generally, chemical energy storage is adopted, and the problems of limited charging and discharging times and the like exist, so that the energy storage technology is generally applied to AGC (automatic generation control) and belongs to the field of secondary frequency modulation. Flywheel energy storage (abbreviated as FES) is an advanced physical energy storage technology from aerospace, and is an energy storage mode that a Flywheel is driven by electric energy to rotate at a high speed, the electric energy is converted into mechanical energy, a motor is dragged by inertia of the Flywheel to generate electricity when needed, and the stored mechanical energy is converted into electric energy to be output (and the Flywheel discharges electricity). Different from other battery technologies, the advantages of the battery are realized on the charge-discharge characteristics of short time, high frequency and high power. The method is mainly applied to the fields of power grid frequency modulation, new energy station grid connection and the like. The flywheel has good energy storage power characteristics and high response speed: millisecond-level high-power charging and discharging and high reliability; high efficiency, maintenance-free: the magnetic suspension support has no friction loss, and the system maintenance period is long; the service life is long: the method is not influenced by repeated deep discharge times, and the service life is generally more than 15 years; green and environment-friendly, and has no pollution: physical energy storage, no chemical substance and no cell later-stage pressure recovery.

Corresponding standards and implementation fine rules of each national regional power grid are formulated according to the two fine rules of the country, the integral electric quantity of the primary frequency modulation is subjected to reward punishment, the primary frequency modulation is basically specified in the implementation fine rules of the auxiliary service management of the grid-connected power plant of each regional power grid, for example, the primary frequency modulation qualification rate specified by the northwest regional power grid is not less than 60%, and the primary frequency modulation qualification rate specified by the Shandong power grid is not less than 70%. As shown in fig. 1, the primary frequency modulation lattice rate is equal to the percentage of the ratio of the actual integral electric quantity of the primary frequency modulation of the unit to the theoretical monthly integral electric quantity, that is, the ratio of the integral area a formed by the theoretical power curve 2 to the integral area B formed by the actual power curve 3. In the actual operation of the unit, due to the inherent delay characteristic of actuating mechanisms such as a turbine governor and the like, the unit does not change or changes slightly in the early stage of the frequency change of a power grid, particularly in the first few seconds, so that on one hand, the frequency modulation control precision is reduced, and the problem that the active variable quantity index does not reach the standard in the power grid examination is examined by the power grid; on the other hand, the untimely adjustment of the frequency modulation compensation power of the unit can cause the instability of the power grid frequency and influence the safe and stable production.

Disclosure of Invention

In order to solve the problems, the invention provides a primary frequency modulation control device of a thermal power generating unit based on flywheel energy storage, which can be coordinated and matched with the thermal power generating unit to realize dynamic rapid compensation of frequency modulation power according to the change of the frequency value of a power grid and the self energy storage capacity, effectively utilize the energy storage and reduce the action of the thermal power generating unit, and ensure the stable operation of the power grid.

Specifically, the invention provides a primary frequency modulation control device of a thermal power generating unit based on flywheel energy storage, which comprises: a function block F (x), a comparator block CMP1, a comparator block CMP2, a comparator block CMP3, an analog quantity selector AXSEL1, an analog quantity selector AXSEL2, an analog quantity selector AXSEL3, an analog quantity selector AXSEL4, an analog quantity selector AXSEL5, a subtractor block DEV1, a subtractor block DEV2, a subtractor block DEV3, a subtractor block DEV4, a logical AND block AND1, a logical AND block AND2, a logical OR block OR, a logical NOT block 1, a logical NOT block NOT2, a logical NOT block NOT 3;

sending the collected frequency measurement value to a subtractor module DEV1 to obtain a frequency difference value with a frequency standard value of 50Hz, calculating and obtaining a corresponding primary frequency modulation power increment delta P through a function module F (x), sending the delta P to a first input end of a comparator module CMP1 to be compared with a value of 0, sending the delta P to a first input end of a comparator module CMP2 to be compared with a collected real-time power value P of the flywheel energy storage device_F-ActualIn comparison, one output of the comparator module CMP1 is sent to the first input terminal of the AND module AND1, one output of the comparator module CMP2 is inverted by the NOT module NOT1 AND sent to the second input terminal of the AND module AND1, ANDThe output of the block AND1 is fed to a first input of a logical OR block OR;

the collected real-time power value P of the flywheel energy storage device_F-ActualAnd rated power value P_F-RatedRespectively sending the difference to a first input end AND a second input end of a subtractor module DEV2, sending one path of the obtained difference to a second input end of a comparator module CMP3, comparing the difference with a primary frequency modulation power increment Δ P received by the first input end of a comparator module CMP3, sending one path of the output of the comparator module CMP3 to a second input end of an AND module AND2, sending one path of the output of the comparator module CMP1 to a first input end of an AND module AND2 after being inverted by a NOT logic module NOT2, AND sending the output of the AND module AND2 to a second input end of an OR module OR;

the output of the logic OR module is sent to a position end of an analog quantity selector AXSEL1, a first input end of the analog quantity selector AXSEL1 receives the primary frequency modulation power increment delta P output by the function module F (x), the output of the analog quantity selector AXSEL1 is sent to a second input end of the analog quantity selector AXSEL2, and a first input end of the analog quantity selector AXSEL2 receives the collected real-time power value P of the flywheel energy storage device_F-ActualThe set end of the analog quantity selector AXSEL2 receives an output signal of the comparator module CMP2, the output of the analog quantity selector AXSEL2 is sent to the second input end of the analog quantity selector AXSEL3, the first input end of the analog quantity selector AXSEL3 receives an output value of the subtractor module DEV2, the set end of the analog quantity selector AXSEL3 receives a signal obtained by inverting the output of the comparator module CMP3 through the logic NOT3, and the output value of the analog quantity selector AXSEL3 is sent to the flywheel energy storage device for power increase and decrease, namely charge and discharge operation;

the primary frequency modulation power increment delta P obtained by the function module F (x) is respectively sent to a first input end of a subtracter module DEV3 and a first input end of a subtracter module DEV4, and a second input end of the subtracter module DEV3 receives the collected real-time power value P of the flywheel energy storage device_FActualA second input of subtractor module DEV4 receives the output of subtractor module DEV2, the output of subtractor module DEV3 is fed to a first input of analog selector AXSEL4, and the set terminal of analog selector AXSEL4 is connected to the output of subtractor module DEV2The output signal of the comparator module CMP2 is received, the output of the subtractor module DEV4 is sent to a first input end of an analog quantity selector AXSEL5, the output of the analog quantity selector AXSEL4 is sent to a second input end of the analog quantity selector AXSEL5, a set end of the analog quantity selector AXSEL5 receives the output signal of a logic NOT3, and the output value of the analog quantity selector AXSEL5 is sent to the unit for power increasing and decreasing.

Wherein a second input of both the analog quantity selector AXSEL1 and the analog quantity selector AXSEL4 is set to a constant of 0.

Further, when the output value of the analog quantity selector AXSEL3 is positive, the flywheel energy storage device performs a discharging operation, and when the output value of the analog quantity selector AXSEL3 is negative, the flywheel energy storage device performs a charging operation.

The output value of the analog quantity selector AXSEL5 is a positive time unit power increasing operation, and the output value of the analog quantity selector AXSEL5 is a negative time unit power decreasing operation.

Compared with the prior art, the invention has the beneficial effects that:

(1) the invention utilizes the capability of a flywheel energy storage system to rapidly and accurately charge and discharge power, makes up the problem of insufficient work in the early stage of frequency modulation caused by the inherent delay characteristic of a thermal power unit, improves the primary frequency modulation control precision of the unit, and meets the requirement of active variation examination indexes in power grid examination.

(2) According to the invention, the power of the flywheel energy storage device is dynamically monitored and the primary frequency modulation compensation power demand is analyzed, the frequency modulation increment is dynamically allocated between the unit and the energy storage device, the flywheel energy storage device is fully utilized for frequency modulation compensation, the interference of the primary frequency modulation on the unit is reduced, the energy saving and consumption reduction are realized, and the stable operation of a power grid is ensured while the energy storage and the unit action are effectively utilized.

Drawings

Fig. 1 is a primary frequency modulation integral electric quantity index calculation chart;

fig. 2 is a flow chart of a primary frequency modulation control method of a thermal power generating unit based on flywheel energy storage.

Fig. 3 is a schematic diagram of a primary frequency modulation control device of a thermal power generating unit based on flywheel energy storage.

Detailed Description

In order to make those skilled in the art better understand the technical solutions in the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

For a better understanding of the present application, embodiments of the present application are explained in detail below with reference to the accompanying drawings.

As shown in fig. 2, the method in this embodiment includes the following processes:

calculating and solving a corresponding primary frequency modulation power increment delta P according to the collected power grid frequency value; according to the collected rated power value P of the flywheel energy storage device_F-RatedAnd real-time power value P_F-ActualCalculating the power value which can be released and absorbed by the flywheel energy storage device; according to the actual power regulation capacity of the flywheel energy storage device, the power variation delta P required to be provided by the unit in the primary frequency modulation compensation action is dynamically judged and distributed_UAnd the power variation delta P required to be provided by the flywheel energy storage device_F。

Wherein, the delta P can be obtained according to the standards of GB/T30370 'Primary frequency modulation test and Performance acceptance guide rules' and the like of the thermal generator set.

(1) When the primary frequency modulation power increment is larger than 0 and not larger than the power value which can be released by the flywheel energy storage device, namely delta P is larger than 0 and is not larger than P_F-ActualAt the moment, the turbine regulating valve of the unit is kept unchanged, the power is kept unchanged, and the flywheel energy storage device only provides the power increment required by primary frequency modulation, namely delta P_U＝0，ΔP_FWhen the flywheel energy storage device is in a discharge state, the unit is in a power increasing state;

(2) when the primary frequency modulation power increment is larger than the power value which can be released by the flywheel energy storage device, namely delta P >, the secondary frequency modulation power increment is larger than the power value which can be released by the flywheel energy storage deviceP_F-ActualWhen the power increment required by primary frequency modulation cannot be provided only by the flywheel energy storage device, the power increment required by the primary frequency modulation, namely delta P, is provided by the unit and the flywheel energy storage device together_U＝ΔP-P_F-Actual，ΔP_F＝P_F-Actual；

(3) When the primary frequency modulation power increment is less than 0 and not more than the power value which can be absorbed by the flywheel energy storage device, namely (P)_F-Actual-P_F-Rated) When the delta P is less than or equal to 0, the turbine regulating valve of the unit is kept unchanged, the power is kept unchanged, redundant power generated by the unit is charged into the flywheel energy storage device according to the primary frequency modulation power increment, and the delta P_U＝0，ΔP_FWhen the flywheel energy storage device is in a charging state, the unit is in a power reduction state, the negative value represents that the flywheel energy storage device is in the charging state;

(4) when the primary frequency modulation power increment is larger than the power value which can be absorbed by the flywheel energy storage device, namely delta P < (P)_F-Actual-P_F-Rated) At the moment, the power increment required by primary frequency modulation is larger than the absorption capacity of the flywheel energy storage device, the unit is required to close the turbine regulating valve to realize the power reduction operation, and the delta P is_U＝ΔP-(P_F-Actual-P_F-Rated)，ΔP_F＝P_F-Actual-P_F-Rated。

Fig. 3 is a schematic diagram of a primary frequency modulation control device of a thermal power generating unit based on flywheel energy storage, referring to fig. 3, the device includes:

a function block F (x), a comparator block CMP1, a comparator block CMP2, a comparator block CMP3, an analog quantity selector AXSEL1, an analog quantity selector AXSEL2, an analog quantity selector AXSEL3, an analog quantity selector AXSEL4, an analog quantity selector AXSEL5, a subtractor block DEV1, a subtractor block DEV2, a subtractor block DEV3, a subtractor block DEV4, a logical AND block AND1, a logical AND block AND2, a logical OR block OR, a logical NOT block 1, a logical NOT block NOT2, a logical NOT block NOT 3;

sending the collected frequency measurement value to subtractor module DEV1 to obtain a frequency difference value with a frequency standard value of 50Hz, calculating and obtaining a corresponding primary frequency modulation power increment delta P through a function module F (x),the delta P is sent to a first input end X1 of a comparator module CMP1 and compared with a value of 0, and the delta P is sent to a first input end X1 of a comparator module CMP2 and collected real-time power value P of the flywheel energy storage device_F-ActualIn comparison, one path of the output of the comparator module CMP1 is sent to the first input terminal Z1 of the AND logic module AND1, one path of the output of the comparator module CMP2 is inverted by the NOT logic module NOT1 AND then sent to the second input terminal Z2 of the AND logic module AND1, AND the output of the AND logic module AND1 is sent to the first input terminal Z1 of the OR logic module OR;

the collected real-time power value P of the flywheel energy storage device_F-ActualAnd rated power value P_F-RatedRespectively sending the difference values to a first input end X1 AND a second input end X2 of a subtractor module DEV2, sending one path of the obtained difference values to a second input end X2 of a comparator module CMP3, comparing the difference values with a primary frequency modulation power increment Δ P received by a first input end X1 of a comparator module CMP3, sending one path of the output of the comparator module CMP3 to a second input end Z2 of a logical AND module AND2, sending one path of the output of the comparator module CMP1 to a first input end Z1 of the logical AND module AND2 after being inverted by a logical NOT module NOT2, AND sending the output of the logical AND module AND2 to a second input end Z2 of a logical OR module OR;

the output of the logic OR module is sent to a set end S of an analog quantity selector AXSEL1, a first input end X1 of the analog quantity selector AXSEL1 receives the primary frequency modulation power increment delta P output by the function module F (X), the output of the analog quantity selector AXSEL1 is sent to a second input end X2 of the analog quantity selector AXSEL2, and a first input end X1 of the analog quantity selector AXSEL2 receives the collected real-time power value P of the flywheel energy storage device_F-ActualThe set terminal S of the analog quantity selector AXSEL2 receives an output signal of the comparator module CMP2, the output of the analog quantity selector AXSEL2 is sent to the second input terminal X2 of the analog quantity selector AXSEL3, the first input terminal X1 of the analog quantity selector AXSEL3 receives an output value of the subtractor module DEV2, the set terminal S of the analog quantity selector AXSEL3 receives a signal obtained by inverting the output of the comparator module CMP3 through the logic NOT3, and the output value of the analog quantity selector AXSEL3 is sent to the flywheel energy storage device for power increase and decrease, namely charge and discharge operation;

the primary frequency modulation power increment Δ P obtained by the function module F (X) is respectively sent to the subtractor module DEV3 and the first input terminal X1 of the subtractor module DEV4, and the second input terminal X2 of the subtractor module DEV3 receives the collected real-time power value P of the flywheel energy storage device_F-ActualThe second input terminal X2 of the subtractor module DEV4 receives the output of the subtractor module DEV2, the output of the subtractor module DEV3 is sent to the first input terminal X1 of the analog quantity selector AXSEL4, the set terminal S of the analog quantity selector AXSEL4 receives the output signal of the comparator module CMP2, the output of the subtractor module DEV4 is sent to the first input terminal X1 of the analog quantity selector AXSEL5, the output of the analog quantity selector AXSEL4 is sent to the second input terminal X2 of the analog quantity selector AXSEL5, the set terminal S of the analog quantity selector AXSEL5 receives the output signal of the logic NOT module NOT3, and the output value of the analog quantity selector AXSEL5 is sent to the unit for power increase and decrease operation.

The second input X2 of both the analog selector AXSEL1 and the analog selector AXSEL4 are set to a constant 0.

Taking the northwest regional power grid as an example, an application example of the method provided by the invention in an actual power grid is given.

In the northwest region, the auxiliary service management implementation rule of the grid-connected power plant is specified, and the monthly average qualification rate of the primary frequency modulation is as follows: the percentage of the ratio of the total actual monthly integrated electric quantity to the theoretical monthly integrated electric quantity of the primary frequency modulation of the generator set.

(1) The average primary frequency modulation qualification rate of the thermal power and gas turbine units is not less than 60 percent.

(2) The average qualification rate of the primary frequency modulation of the hydroelectric generating set is not less than 50 percent.

And compensating the monthly primary frequency modulation average qualified rate for 5 minutes according to the compensation rate of 1 percent higher. Wherein, the integral electric quantity of primary frequency modulation: when the frequency of the power grid exceeds 50 +/-0.033 Hz (the hydroelectric generating set is calculated according to 50 +/-0.05 Hz) and is recovered to 50 +/-0.033 Hz (the hydroelectric generating set is calculated according to 50 +/-0.05 Hz), the integral electric quantity of the difference between the actual generated output and the initial actual generated output is a positive value, and conversely, the high-frequency low-frequency high-frequency electric quantity or the low-frequency electric quantity is a negative value. The integral electric quantity of the primary frequency modulation of the unit in the month is the algebraic sum of the electric quantity of the primary frequency modulation when the frequency of the power grid exceeds 50 +/-0.033 Hz (the hydroelectric generating unit is calculated according to 50 +/-0.05 Hz) in the month.

The 300 MW-level positive pressure direct blowing type unit is mainly used in the net, a 300MW unit is selected for analysis, and a set of 10MW flywheel energy storage device is constructed in an auxiliary mode. According to the primary frequency modulation management regulations of GB/T30370 Primary frequency modulation test and Performance acceptance guide of thermal generator sets and the like, the rotating speed is not equal to 5%, the maximum frequency modulation amplitude is 8% of rated capacity, namely +/-24 MW, and the specific parameters set in the corresponding function module F (x) are shown in Table 1.

TABLE 1 function module F (x) intermediate frequency difference-power corresponding function

Frequency difference value Hz	Power increment MW
		0.5	24
0.233	24
		0.033	0
0	0
		-0.033	0
-0.233	-24
		-0.5	-24

At a certain moment, a power grid frequency measured value 49.867Hz is acquired, the frequency difference value is 50-49.867-0.133 Hz, the corresponding primary frequency modulation power increment delta P is 12MW, and the real-time power value of the flywheel energy storage device is P at the moment_F-Actual＝8MW，ΔP＞P_F-ActualThe power increment of primary frequency modulation is larger than the power value which can be released by the flywheel energy storage device, the power increment required by the primary frequency modulation cannot be provided by the flywheel energy storage device only, and the power increment, delta P, required by the primary frequency modulation is provided by the unit and the flywheel energy storage device together at the moment_U＝ΔP-P_F-Actual＝4MW，ΔP_F＝P_F-Actual8 MW. The specific control flow is as follows:

sending the collected frequency measurement value 49.867Hz to a subtractor module DEV1 to obtain a frequency difference value of 0.133Hz with a frequency standard value of 50Hz, and calculating and obtaining a corresponding primary frequency modulation power increment Δ P of 12MW through a function module F (x);

Δ P is applied to the first input X1 of the comparator module CMP1 to compare with a constant 0, and since 12 > 0, the output of the comparator module CMP2 is high level "1";

Δ P is sent to the first input end X1 of the comparator module CMP2 and the collected real-time power value P of the flywheel energy storage device_F-ActualIn comparison, since 12 > 8, the output of the comparator module CMP2 is high level "1";

Δ P is provided to the first input X1 of the comparator module CMP3 to be compared with the output of the subtractor module DEV2, the output of the subtractor module DEV2 is 8-10 ═ 2, and the output of the comparator module CMP3 is high level "1" since 12 > -2;

a high level "1" of the comparator module CMP1 is provided to the first input terminal Z1 of the AND logic module AND1, a high level "1" output of the comparator module CMP2 is inverted by the NOT logic module NOT1 to become a low level "0" AND is provided to the second input terminal Z2 of the AND logic module AND1, AND since two inputs of the AND logic module AND1 are respectively a high level "1" AND a low level "0", the AND logic module CMP1 outputs a low level "0" to the first input terminal Z1 of the OR logic module OR;

the high level "1" output of the comparator module CMP1 is inverted by the NOT module NOT2 AND then turned into a low level "0" to be sent to the first input terminal Z1 of the AND module AND2, AND the high level "1" of the comparator module CMP3 is sent to the second input terminal Z2 of the AND module AND1, AND since the two inputs of the AND module AND2 are respectively the low level "0" AND the high level "1", it outputs the low level "0" to the second input terminal Z2 of the OR module OR;

if both the two inputs of the OR logic block OR are low level "0", the output thereof is low level "0", the set terminal S of the analog quantity selector AXSEL1 is low level "0", and the input value 0 of the second input terminal X2 is selected to be output to the second input terminal X2 of the analog quantity selector AXSEL 2; the set terminal S of the analog quantity selector AXSEL2 receives the output high level "1" from the comparator module CMP2, selects the input value P of the first input terminal X1_F-ActualThe output is output to a second input X2 of the analog quantity selector AXSEL3 at 8 MW; the high level "1" output of the comparator module CMP3 is inverted by the NOT module NOT3 and then becomes low level "0" to be sent to the set terminal S of the analog quantity selector AXSEL3, and the analog quantity selector AXSEL3 selects the input value P of the second input terminal X2_F-ActualAnd 8MW output, namely the flywheel energy storage device selects to release the residual energy of 8 MW.

The set terminal S of the analog quantity selector AXSEL4 receives the output high level "1" from the comparator module CMP2, and selects to output the input value of the first input terminal X1 to the second input terminal X2 of the analog quantity selector AXSEL5, i.e., the output Δ P of the subtractor module DEV3_U＝ΔP-P_F-ActualA second input X2 of the analog quantity selector AXSEL5 is output with 12-8 ═ 4 MW; the high level "1" output of the comparator module CMP3 is inverted by the NOT module NOT3 and then becomes a low level "0" to be sent to the set end S of the analog quantity selector AXSEL5, and the analog quantity selector AXSEL5 selects to output the input value of the second input end X2 of 4MW, that is, the unit needs to perform power boost of 4MW at this time.

Although the embodiments of the present invention have been described with reference to the accompanying drawings, it is not intended to limit the scope of the present invention, and it should be understood by those skilled in the art that various modifications and variations can be made without inventive efforts by those skilled in the art based on the technical solution of the present invention.

Claims

1. The utility model provides a thermal power generating unit primary control device based on flywheel energy storage which characterized in that includes: a function block F (x), a comparator block CMP1, a comparator block CMP2, a comparator block CMP3, an analog quantity selector AXSEL1, an analog quantity selector AXSEL2, an analog quantity selector AXSEL3, an analog quantity selector AXSEL4, an analog quantity selector AXSEL5, a subtractor block DEV1, a subtractor block DEV2, a subtractor block DEV3, a subtractor block DEV4, a logical AND block AND1, a logical AND block AND2, a logical OR block OR, a logical NOT block 1, a logical NOT block NOT2, a logical NOT block NOT 3;

sending the collected frequency measurement value to a subtractor module DEV1 to obtain a frequency difference value with a frequency standard value of 50Hz, calculating and obtaining a corresponding primary frequency modulation power increment delta P through a function module F (x), sending the delta P to a first input end of a comparator module CMP1 to be compared with a value of 0, sending the delta P to a first input end of a comparator module CMP2 to be compared with a collected real-time power value P of the flywheel energy storage device_F-ActualIn comparison, one output of the comparator module CMP1 is sent to the first input terminal of the AND logic module AND1, one output of the comparator module CMP2 is inverted by the NOT logic module NOT1 AND then sent to the second input terminal of the AND logic module AND1, AND the output of the AND logic module AND1 is sent to the first input terminal of the OR logic module OR;

the collected real-time power value P of the flywheel energy storage device_F-ActualAnd rated power value P_F-RatedRespectively sending the difference to a first input end AND a second input end of a subtractor module DEV2, sending one path of the obtained difference to a second input end of a comparator module CMP3, comparing the difference with a primary frequency modulation power increment delta P received by the first input end of a comparator module CMP3, sending one path of the output of the comparator module CMP3 to a second input end of a logic AND module AND2, AND sending one path of the output of the comparator module CMP1 to a second input end of a logic NOT2 after being inverted by the logic NOT2To a first input of an AND-logic-AND-block AND2, AND the output of the AND-logic-block AND2 is supplied to a second input of an OR-logic-OR-block OR;

the primary frequency modulation power increment delta P obtained by the function module F (x) is respectively sent to a first input end of a subtracter module DEV3 and a first input end of a subtracter module DEV4, and a second input end of the subtracter module DEV3 receives the collected real-time power value P of the flywheel energy storage device_F-ActualThe second input terminal of the subtractor module DEV4 receives the output of the subtractor module DEV2, the output of the subtractor module DEV3 is sent to the first input terminal of the analog quantity selector AXSEL4, the set terminal of the analog quantity selector AXSEL4 receives the output signal of the comparator module CMP2, the output of the subtractor module DEV4 is sent to the first input terminal of the analog quantity selector AXSEL5, the output of the analog quantity selector AXSEL4 is sent to the second input terminal of the analog quantity selector AXSEL5, the set terminal of the analog quantity selector AXSEL5 receives the output signal of the logic NOT module NOT3, and the output value of the analog quantity selector AXSEL5 is sent to the unit for power increase and decrease operation.

2. The apparatus of claim 1, wherein a second input of the analog quantity selector AXSEL1 and the analog quantity selector AXSEL4 are each set to a constant 0.

3. The apparatus of claim 2 wherein the flywheel energy storage device performs a discharging operation when the output of the analog quantity selector AXSEL3 is positive and performs a charging operation when the output of the analog quantity selector AXSEL3 is negative.

4. The apparatus of claim 3, wherein the output value of the analog selector AXSEL5 is a positive bank power boost operation and the output value of the analog selector AXSEL5 is a negative bank power reduction operation.

5. The apparatus of claim 1, wherein the primary modulation power increment is greater than 0 and not greater than the amount of power that can be delivered by the flywheel energy storage device, i.e., 0 < Δ P ≦ P_F-ActualAt the moment, the turbine regulating valve of the unit is kept unchanged, the power is kept unchanged, and the flywheel energy storage device only provides the power increment required by primary frequency modulation.

6. The apparatus of claim 5, wherein the power variation Δ P to be supplied by the aggregate is_U0, the amount of power change Δ P that the flywheel energy storage device needs to provide_F＝ΔP。

7. The apparatus of claim 1, wherein the primary modulation power increment is greater than the amount of power that the flywheel energy storage device can deliver, i.e., Δ P > P_F-ActualAnd at the moment, the unit and the flywheel energy storage device jointly provide the power increment required by primary frequency modulation.

8. The apparatus of claim 7, wherein the power increment Δ P to be supplied by the unit_U＝ΔP-P_F-ActualThe power value delta P to be released by the flywheel energy storage device_F＝P_F-Actual。

9. An apparatus as claimed in claim 1, wherein (P) is the increase in primary modulated power when the increase in primary modulated power is less than 0 and not greater than the amount of power that the flywheel energy storage device can absorb_F-Actual-P_F-Rated) When the delta P is less than or equal to 0, the turbine regulating valve of the unit is kept unchanged, the power is kept unchanged, and redundant power generated by the unit is charged into the flywheel energy storage device according to the primary frequency modulation power increment.

10. The apparatus of claim 9, wherein the power variation Δ P to be supplied by the aggregate is_U0, the amount of power change Δ P that the flywheel energy storage device needs to provide_F＝ΔP。

11. An apparatus as claimed in claim 1, wherein Δ P < (P) is the amount of primary modulated power that can be absorbed by the flywheel energy storage device when the primary modulated power increase is greater than the amount of power that can be absorbed by the flywheel energy storage device_F-Actual-P_F-Rated) At the moment, the power increment required by primary frequency modulation is larger than the absorption capacity of the flywheel energy storage device, and the turbine set is required to close the turbine regulating valve to realize the operation of power reduction.

12. The apparatus of claim 11, wherein the power reduction Δ P to be provided by the unit is a value_U＝ΔP-(P_F-Actual-P_F-Rated) The power value delta P that the flywheel energy storage device can absorb_F＝P_F-Actual-P_F-Rated。