Adjusting strategy for coupling super capacitor of thermal power generating unit

Abstract

The invention relates to an adjusting strategy for a coupling super capacitor of a thermal power generating unit, which comprises the following steps: acquiring operation data of the thermal power generating unit in an accumulated time period, and calculating according to the operation data to obtain adjusting conditions including a unit frequency modulation inertia time constant, an adjusting error degree, an adjusting error maximum value and a delay instruction error; judging an adjustment problem corresponding to the thermal power generating unit according to the adjustment condition and the AGC frequency modulation instruction requirement, and introducing an adjustment strategy corresponding to adjustment parameter optimization; monitoring the operation state of the thermal power generating unit in real time, and applying a corresponding adjustment strategy according to the frequency modulation state of the thermal power generating unit; wherein when the unit is subjected to reverse adjustment and excessive adjustment occurs, the super capacitor is coupled with the thermal power unit for additional compensation; the super-capacitor assists the thermal power generating unit in participating in AGC frequency modulation, the problems that the thermal power generating unit is low in response speed and poor in frequency modulation performance are effectively solved, and the super-capacitor and the thermal power generating unit cooperate with each other to complete an AGC instruction.

Description

Technical Field

[0001] The invention belongs to the technical field of thermal power unit control, and in particular relates to a regulation strategy for coupling supercapacitors of thermal power units. Background Art

[0002] In the operation of the power system, solving the problem of short-term random active imbalance in the regional power grid, that is, the power grid frequency and tie line power control is mainly achieved through automatic generation control (AGC). AGC puts forward high requirements on the performance of frequency-regulated power supply, such as fast regulation rate, high regulation accuracy, and frequent switching of power regulation direction. The AGC frequency regulation function is mainly provided by conventional power sources including hydropower, gas units and thermal power units. Since these power supply systems have rotational inertia, converting primary energy into electrical energy will go through a series of complex processes. In particular, the AGC frequency regulation performance of thermal power units is still far from the expectations of the power grid, which is manifested in the current situation of regulation delay and deviation.

[0003] For example, CN113690943B "A method and system for energy storage control for tracking the AGC regulation deviation of thermal power units" discloses "a method and system for energy storage control for tracking the AGC regulation deviation of thermal power units, the method comprising: S1, a task requirement module collects the AGC command value issued by the power grid dispatch to the thermal power unit and the real-time output power of the thermal power unit to determine the AGC regulation deviation of the thermal power unit; S2, an energy storage tracking judgment module determines whether to start the adjustment module according to the AGC regulation deviation of the thermal power unit; S3, the adjustment module determines the actual output power of the battery energy storage system; S4, the feedback control module determines the final actual output of the energy storage system based on the real-time output power of the thermal power unit and the actual output power of the battery energy storage system", but the method only relies on the AGC regulation deviation of the thermal power unit to start the adjustment module, and cannot comprehensively consider more influencing factors, which will lead to a delayed response to the regulation demand. In addition, the feedback control module of the method is relatively simple, and does not consider more detailed adjustment strategies, which limits the flexibility and adaptability of the system when facing complex power grid conditions. Summary of the invention

[0004] In order to solve the above problems existing in the prior art, the present application provides a regulation strategy for coupling supercapacitors of thermal power units.

[0005] The technical solution of this application is as follows:

[0006] A regulation strategy for coupling supercapacitors of thermal power units, the strategy comprising:

[0007] Acquire the operation data of the thermal power unit within the cumulative time period, wherein the operation data includes the automatic generation control AGC frequency regulation instruction and the output of the thermal power unit; calculate the regulation status according to the operation data, wherein the regulation status includes the unit frequency regulation inertia time constant, regulation error degree, regulation error maximum value and delay instruction error;

[0008] According to the regulation situation and the AGC frequency regulation instruction requirements, the regulation problem corresponding to the thermal power unit is judged, and the regulation strategy corresponding to the optimization of the regulation parameters is introduced, wherein the regulation parameters include a balance coefficient, a compensation coefficient and a delay compensation, and the regulation strategy includes a reverse regulation, a deviation regulation and a delay regulation, wherein the optimization relationship sequence of the regulation parameters and the regulation strategy corresponds;

[0009] The operating status of the thermal power unit is monitored in real time, and the corresponding adjustment strategy is applied according to the operating status of the thermal power unit; when the unit is reversely adjusted and over-adjusted, the supercapacitor is used to couple the thermal power unit for additional compensation.

[0010] Preferably, the strategy also includes data cleaning of the acquired operating data, wherein the data cleaning includes processing missing values, outliers and unifying data formats.

[0011] Preferably, the unit frequency regulation inertia time constant is calculated based on the operating data, specifically:

[0012] According to the AGC frequency modulation instruction P agc And thermal power group output P h Calculate the slope dP of the AGC frequency modulation command agc and the slope dP of the thermal power unit output h ; Statistical accumulation of slope dP within the time period agc and slope dP h Number of opposite signs N 1 , and record the time t corresponding to the opposite sign i , according to the number N 1 and time t i Calculate the unit frequency regulation inertia time constant S 1 , expressed as:

[0013]

[0014] Preferably, a balance coefficient is introduced to perform reverse regulation, specifically:

[0015] When it is detected that the absolute value of the slope of the AGC frequency modulation instruction becomes smaller, a balance coefficient Q is added based on the output of the thermal power unit. The balance coefficient Q is expressed by the formula:

[0016]

[0017] In the formula, tanh() represents the activation function; sigmoid() represents the activation function.

[0018] Preferably, the adjustment error degree is calculated based on the operating data and is expressed as:

[0019]

[0020] In the formula, S 2 represents the degree of adjustment error, and t represents the cumulative time period of the statistical data;

[0021] The maximum value of the adjustment error is calculated based on the operating data and expressed as follows:

[0022] Z=max(P 1 -P 2 );

[0023] Where Z represents the maximum value of the adjustment error, P 1 Indicates the target of AGC frequency modulation instruction, P 2 It represents the actual regulation result of the thermal power unit, and max() represents the maximum value function.

[0024] Preferably, a compensation coefficient is introduced to adjust the deviation, specifically:

[0025] When the AGC frequency modulation instruction deviates from the output of the thermal power unit, a compensation coefficient B is added to the output of the thermal power unit. The compensation coefficient B is expressed as follows:

[0026]

[0027] Where rand() represents the random function and ln() represents the logarithmic function.

[0028] Preferably, the delay instruction error is obtained by calculating according to the operation data, specifically:

[0029] Count the number of times N that the AGC frequency modulation command has adjustment delay within the cumulative time period 2 , and record the corresponding delay time δt i , according to the AGC frequency modulation instruction P agc 、Thermal power group output P h and delay time δt i Calculate the delay instruction error Δ i , expressed as:

[0030]

[0031] Preferably, delay compensation is introduced to perform delay adjustment, specifically:

[0032] After detecting the time delay between the issuance of the AGC frequency modulation command and the actual response, a delay compensation A is added based on the output of the thermal power unit. The delay compensation A is expressed as follows:

[0033]

[0034] Where avg() represents the average function, and sin() represents the sine function.

[0035] Preferably, according to the frequency regulation state of the thermal power unit, a corresponding regulation strategy is applied, specifically:

[0036] When there is no regulation deviation or reverse regulation in the thermal power unit, the output P of the optimized thermal power unit h1 , expressed as:

[0037] P h1 =P h +A;

[0038] When the thermal power unit is regulated in reverse, the output P of the optimized thermal power unit h2 , expressed as:

[0039] P h2 =P h +A+Q;

[0040] When the thermal power unit has a regulation deviation, the optimized thermal power unit output P h3 , expressed as:

[0041] P h3 =P h +A+B.

[0042] Preferably, when the unit is reversely regulated and over-regulation occurs, supercapacitor coupling thermal power units are used for additional compensation, specifically:

[0043] When the thermal power unit is reversely regulated, if the current output of the thermal power unit is P h +A+S, and the current thermal power unit output and AGC frequency regulation instruction P agc When the error between exceeds the preset threshold, over-regulation occurs, which can be expressed as:

[0044]

[0045] The supercapacitor coupled thermal power unit provides additional compensation, and the compensation power is P c , expressed as:

[0046]

[0047] Compared with the prior art, the present invention has the following beneficial effects:

[0048] 1) The present invention provides a regulation strategy for coupling a supercapacitor to a thermal power unit, which is regulated by coupling the thermal power unit to a supercapacitor for energy storage, thereby effectively shortening the frequency modulation response time, improving the regulation rate of the entire frequency modulation system, and meeting the strict requirements of AGC frequency modulation on power supply performance;

[0049] 2) The present invention provides a regulation strategy for coupling supercapacitors of thermal power units. By statistically analyzing the error between the frequency regulation instruction and the actual output of the thermal power unit and introducing a compensation coefficient, the precise adjustment of the unit output is achieved, the deviation in the regulation process is effectively reduced, and the completion quality of the frequency regulation instruction is improved. Stable control of the grid frequency and the tie line power is ensured;

[0050] 3) The present invention provides a regulation strategy for coupling supercapacitors of thermal power units. Based on the definition of the frequency modulation inertia time constant and the introduction of a balance coefficient, the reverse frequency modulation behavior of the thermal power units is effectively suppressed, providing a strong guarantee for the stable operation of the power system. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 It is a flow chart of a method according to an embodiment of the present invention. DETAILED DESCRIPTION

[0052] The specific implementation modes of the present invention are described below so that those skilled in the art can understand the present invention. However, it should be clear that the present invention is not limited to the scope of the specific implementation modes. For those of ordinary skill in the art, as long as various changes are within the spirit and scope of the present invention as defined and determined by the attached claims, these changes are obvious, and all inventions and creations utilizing the concept of the present invention are protected.

[0053] The present invention provides the following technical solution: a regulation strategy for coupling supercapacitors of thermal power units.

[0054] Example 1

[0055] This embodiment provides a regulation strategy for coupling supercapacitors of thermal power units, and the specific steps include:

[0056] S1. Acquire the operation data of the thermal power unit within the cumulative time period, wherein the operation data includes the automatic generation control AGC frequency modulation instruction and the output of the thermal power unit; further, perform data cleaning on the operation data acquired in this embodiment, wherein the data cleaning includes processing missing values, abnormal values ​​and unifying the data format;

[0057] S2. Calculate and obtain a regulation status according to the operation data, wherein the regulation status includes a frequency regulation inertia time constant of the unit, a regulation error degree, a maximum regulation error, and a delay instruction error;

[0058] S21, unit frequency regulation inertia time constant;

[0059] According to the AGC frequency modulation instruction P agc And thermal power group output P h Calculate the slope dP of the AGC frequency modulation command agc and the slope dP of the thermal power unit output h ; Calculate the slope dP of the AGC frequency modulation instruction agc and the slope dP of the thermal power unit output h ; Statistical accumulation of slope dP within the time period agc and slope dP h Number of opposite signs N 1 , and record the time t corresponding to the opposite sign i , according to the number N 1 and time t i Calculate the unit frequency regulation inertia time constant S 1 , expressed as:

[0060]

[0061] S22. The regulation error degree refers to the error degree between the regulation power of the thermal power unit and the AGC frequency regulation instruction target, which is expressed by the formula:

[0062]

[0063] In the formula, S 2 represents the degree of adjustment error, and t represents the cumulative time period of the statistical data;

[0064] The maximum value of the adjustment error calculated according to the operating data is expressed as follows:

[0065] Z=max(P 1 -P 2 );

[0066] Where Z represents the maximum value of the adjustment error, P 1 Indicates the target of AGC frequency modulation instruction, P 2 It indicates the actual adjustment result of the thermal power unit, and max() indicates the maximum value function;

[0067] S23, count the number of times N that the AGC frequency modulation instruction is delayed in the cumulative time period 2 , and record the corresponding delay time δt i , according to the AGC frequency modulation instruction P agc 、Thermal power group output P h Delay time δt i Calculate the delay instruction error Δ i , expressed as:

[0068]

[0069] S3, judging the regulation problem corresponding to the thermal power unit according to the regulation situation and the AGC frequency regulation instruction requirements, introducing the regulation strategy corresponding to the optimization of the regulation parameters, wherein the regulation parameters include the balance coefficient, the compensation coefficient and the delay compensation, and the regulation strategy includes the reverse regulation, the deviation regulation and the delay regulation, wherein the optimization relationship between the regulation parameters and the regulation strategy corresponds in sequence;

[0070] S31. The balance coefficient is a parameter used to describe the stability and dynamic response characteristics of a system, and is usually used in control theory and engineering applications. It indicates the ability of a system to return to a balanced state when subjected to external disturbances or input changes. Specifically, the larger the balance coefficient, the faster the system recovers and the stronger its stability when facing disturbances, showing better anti-interference ability and regulation performance. A smaller balance coefficient may lead to slow system response, oscillation, or even instability.

[0071] S32. The compensation coefficient is a parameter used to adjust and optimize the performance of the control system, and is mainly used to adjust the response characteristics of the system to the input signal or disturbance; it improves the stability, dynamic response and accuracy of the system by introducing additional feedback or feedforward control;

[0072] S33. The delay compensation is a control strategy that aims to reduce or eliminate the negative impact caused by signal transmission delay by adjusting the feedback mechanism of the system; by introducing delay compensation, the control action of the system can be predicted and adjusted in advance so that when the actual signal arrives, the system can respond quickly and accurately;

[0073] S34, the reverse regulation refers to the situation that the AGC dispatching instruction requires an increase in output, but the unit reduces output due to inertia or other reasons, resulting in frequency fluctuation and poor regulation accuracy; the frequency regulation inertia time constant is defined to measure the strength of the reverse regulation degree of the thermal power unit;

[0074] Introduce the balance coefficient for reverse adjustment. When the slope dP of the AGC frequency modulation instruction agc When the absolute value becomes smaller, the balance coefficient Q is added on the basis of the output of the thermal power unit. The balance coefficient Q is expressed by the formula:

[0075]

[0076] In the formula, tanh() and sigmoid() both represent activation functions;

[0077] S35, the deviation adjustment means adding a compensation coefficient B based on the output of the thermal power unit after detecting a deviation between the AGC frequency modulation instruction and the output of the thermal power unit. The compensation coefficient B is expressed by the formula:

[0078]

[0079] Wherein, rand() represents a random function, ln() represents a logarithmic function, and the logarithmic function is a logarithmic function with e as the base;

[0080] S36, the delay adjustment means that when there is a time delay between the issuance of the AGC frequency modulation instruction and the actual response, a delay compensation A is added to the output of the thermal power unit. The delay compensation A is expressed by the formula:

[0081]

[0082] In the formula, avg() represents the average function, sin() represents the sine function;

[0083] S4. Real-time monitoring of the operating status of the thermal power unit, and application of corresponding regulation strategies according to the frequency regulation status of the thermal power unit; when the unit is reversely regulated and over-regulated, the supercapacitor is used to couple the thermal power unit for additional compensation;

[0084] S41. Apply a corresponding regulation strategy according to the frequency regulation state of the thermal power unit;

[0085] When there is no regulation deviation or reverse regulation in the thermal power unit, the output P of the optimized thermal power unit h1 , expressed as:

[0086] P h1 =P h +A;

[0087] When the thermal power unit is regulated in reverse, the output P of the optimized thermal power unit h2 , expressed as:

[0088] P h2 =P h +A+Q;

[0089] When the thermal power unit has a regulation deviation, the optimized thermal power unit output P h3 , expressed as:

[0090] P h3 =P h +A+B;

[0091] S42. When the unit is reversely regulated and over-regulated, supercapacitor coupling thermal power units are used for additional compensation:

[0092] When the thermal power unit is reversely regulated, if the current output of the thermal power unit is P h +A+S, and the current thermal power unit output and AGC frequency regulation instruction P agc When the error between the output of the thermal power unit and the AGC frequency modulation instruction exceeds the preset threshold, overregulation occurs; the preset threshold is a reasonable error range or error value obtained by analyzing the error data between the output of the thermal power unit and the AGC frequency modulation instruction in the past period of time under the premise of satisfying system stability. In this embodiment, the preset threshold is 8%;

[0093] The overregulation is expressed as:

[0094]

[0095] The supercapacitor coupled thermal power unit provides additional compensation, and the compensation power is P c , expressed as:

[0096]

[0097] S5. In order to further verify the advantages of the method proposed in the present invention, the frequency modulation strategy of the present invention and the traditional strategy are used for comparison, and the results are shown in Table 1;

[0098] Table 1 Comparison results

[0099] FM command 1 Traditional strategies Strategy of the present invention <![CDATA[K 1 (rate)]]> 0.49 0.53 <![CDATA[K 2 (Accuracy)]]> 4.85 5.48 <![CDATA[K 3 (Response Time)]]> 2.62 3.57

[0100] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A regulation strategy for coupling supercapacitors of thermal power units, characterized in that: The strategies include: Acquire the operation data of the thermal power unit within the cumulative time period, wherein the operation data includes the automatic generation control AGC frequency regulation instruction and the output of the thermal power unit; calculate the regulation status according to the operation data, wherein the regulation status includes the unit frequency regulation inertia time constant, regulation error degree, regulation error maximum value and delay instruction error; According to the regulation situation and the AGC frequency regulation instruction requirements, the regulation problem corresponding to the thermal power unit is judged, and the regulation strategy corresponding to the optimization of the regulation parameters is introduced, wherein the regulation parameters include a balance coefficient, a compensation coefficient and a delay compensation, and the regulation strategy includes a reverse regulation, a deviation regulation and a delay regulation, wherein the optimization relationship sequence of the regulation parameters and the regulation strategy corresponds; The operating status of the thermal power unit is monitored in real time, and the corresponding adjustment strategy is applied according to the operating status of the thermal power unit; when the unit is reversely adjusted and over-adjusted, the supercapacitor is used to couple the thermal power unit for additional compensation.

2. The regulation strategy for coupling supercapacitors of a thermal power unit according to claim 1, characterized in that: The strategy also includes performing data cleaning on the acquired operation data, wherein the data cleaning includes processing missing values, abnormal values ​​and standardizing the data format.

3. The regulation strategy for coupling supercapacitors of a thermal power unit according to claim 2, characterized in that: The unit frequency regulation inertia time constant is calculated based on the operating data, specifically: According to the AGC frequency modulation instruction P agc And thermal power group output P h Calculate the slope dP of the AGC frequency modulation command agc and the slope dP of the thermal power unit output h ; Statistical accumulation of slope dP within the time period agc and slope dP h The number of times the sign is opposite is N1, and the time t corresponding to the opposite sign is recorded i , according to the number N1 and time t i The inertia time constant S1 of the unit frequency regulation is calculated and expressed as:

4. The regulation strategy for coupling supercapacitors of a thermal power unit according to claim 3 is characterized in that: The balance coefficient is introduced for reverse adjustment, specifically: When it is detected that the absolute value of the slope of the AGC frequency modulation instruction becomes smaller, a balance coefficient Q is added based on the output of the thermal power unit. The balance coefficient Q is expressed by the formula: In the formula, tanh() represents the activation function; sigmoid() represents the activation function.

5. The regulation strategy for coupling supercapacitors of a thermal power unit according to claim 4, characterized in that: The degree of adjustment error is calculated based on the operating data and expressed as: In the formula, S2 represents the degree of adjustment error, and t represents the cumulative time period of statistical data; The maximum value of the adjustment error is calculated based on the operating data and expressed as follows: Z = max(P1-P2); Where Z represents the maximum value of the regulation error, P1 represents the target of the AGC frequency regulation instruction, P2 represents the actual regulation result of the thermal power unit, and max() represents the maximum value function.

6. The regulation strategy for coupling supercapacitors of a thermal power unit according to claim 5, characterized in that: The compensation coefficient is introduced to adjust the deviation, specifically: When the AGC frequency modulation instruction deviates from the output of the thermal power unit, a compensation coefficient B is added to the output of the thermal power unit. The compensation coefficient B is expressed as follows: Where rand() represents the random function and ln() represents the logarithmic function.

7. A regulation strategy for coupling supercapacitors of a thermal power unit according to claim 6, characterized in that: The delay instruction error is calculated based on the operating data, specifically: Count the number of times N2 that the AGC frequency modulation command is delayed during the cumulative time period, and record the corresponding delay time δt i , according to the AGC frequency modulation instruction P agc 、Thermal power group output P h and delay time δt i Calculate the delay instruction error Δ i , expressed as:

8. The regulation strategy for coupling supercapacitors of a thermal power unit according to claim 7, characterized in that: Delay compensation is introduced to adjust the delay, specifically: After detecting the time delay between the issuance of the AGC frequency modulation command and the actual response, a delay compensation A is added based on the output of the thermal power unit. The delay compensation A is expressed as follows: Where avg() represents the average function, and sin() represents the sine function.

9. The regulation strategy for coupling supercapacitors of a thermal power unit according to claim 8, characterized in that: According to the operating status of the thermal power unit, the corresponding adjustment strategy is applied, specifically: When there is no regulation deviation or reverse regulation in the thermal power unit, the output P of the optimized thermal power unit h1 , expressed as: P h1 =P h +A; When the thermal power unit is regulated in reverse, the output P of the optimized thermal power unit h2 , expressed as: P h2 =P h +A+Q; When the thermal power unit has a regulation deviation, the optimized thermal power unit output P h3 , expressed as: P h3 =P h +A+B。 10. A thermal power unit coupling supercapacitor regulation strategy according to claim 9, characterized in that: When the unit is reversely regulated and over-regulated, supercapacitor coupling thermal power units are used for additional compensation, specifically: When the thermal power unit is reversely regulated, if the current output of the thermal power unit is P h +A+S, and the current thermal power unit output and AGC frequency regulation instruction P agc When the error between exceeds the preset threshold, over-regulation occurs, which can be expressed as: The supercapacitor coupled thermal power unit provides additional compensation, and the compensation power is P c , expressed as:

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