Task intelligent management and control system and method for maintenance of hydroelectric generating set

Abstract

The invention relates to the field of hydroelectric generating set maintenance, in particular to an intelligent task management and control system and method for hydroelectric generating set maintenance, and the system comprises an efficiency evaluation module, a task management module, a frequency tracing module, a loss compensation module and a maintenance evaluation module. The task management module is used for determining the overhaul time and the overhaul task duration, the frequency tracing module is used for corresponding to the frequency component and the water turbine, the loss compensation module is used for calculating the loss power and adjusting the electromagnetic braking torque, and the overhaul evaluation module is used for evaluating the overhaul effect. Meanwhile, maintenance tasks are reasonably arranged, long-term stable operation of the hydroelectric generating set is ensured, energy loss in the maintenance period is evaluated, and the influence of maintenance behaviors on a power grid is reduced to the maximum extent.

Description

Technical Field

[0001] The present invention relates to the field of maintenance of hydropower units, and in particular to a task intelligent management and control system and method for maintenance of hydropower units. Background Art

[0002] A hydroelectric unit is a device consisting of a turbine and a generator. It is used to convert water energy into electrical energy in a hydropower station. It is usually composed of a turbine, a generator, an electromagnetic speed governor, a control system and other components. It can convert the mechanical energy generated by rotation into electrical energy and output it to users. When generating electricity, the frequency of the current emitted by the hydroelectric unit must remain constant to meet the power demand of the power grid.

[0003] However, as the hydropower unit operates, the turbine may malfunction due to mechanical wear, line aging, etc. Therefore, regular maintenance of the turbine is necessary. However, the degree of wear of different turbines is different, and it is difficult to accurately determine the maintenance time of the turbine, nor can it determine the effect of each maintenance. The regular maintenance method has defects.

[0004] In addition, when a turbine is shut down for maintenance, the electricity generated by the entire unit will be affected. In order to avoid the impact of unstable power on the power grid, all turbines need to be shut down during regular maintenance of hydropower units. This will not only extend the power generation time and waste power generation energy, but also easily increase the risk of power grid undervoltage and generator failure. Summary of the invention

[0005] The purpose of the present invention is to provide a task intelligent management and control system and method for maintenance of hydropower units to solve the problems raised in the above-mentioned background technology.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions: a task intelligent management and control system for maintenance of hydropower units, comprising: an efficiency evaluation module, a task management module, a frequency tracing module, a loss compensation module and a maintenance evaluation module;

[0007] The efficiency evaluation module is used to obtain the working data of the hydropower unit by using the sensor, calculate the expected power generation of the hydropower unit according to the water pressure of the reservoir and the speed of the turbine, divide it by the time power generation of the turbine, calculate the power generation efficiency of the turbine, and draw a function of the change of the power generation efficiency of the turbine over time;

[0008] The task management module is used to evaluate the efficiency drop rate of the turbine according to the derivative of the function of the change of the power generation efficiency of the turbine over time, calculate the time when the working efficiency of each turbine drops to the threshold value according to the efficiency drop rate and the current efficiency, record it as the maintenance time of the turbine, generate the maintenance task arrangement according to the maintenance time of each turbine, and determine the maintenance task duration according to the interval between the maintenance times of two turbines;

[0009] The frequency tracing module is used to sample the AC frequency signal, calculate the frequency component of the excitation current of each turbine in the AC according to the frequency sample and the speed of the turbine corresponding to the task, and make the frequency of the component correspond to the number of the turbine one by one;

[0010] The loss compensation module is used to calculate the loss power of the output electric energy during the maintenance process according to the maintenance task duration and the frequency component of the turbine to be repaired during the maintenance of the turbine, distribute the loss power to the working tasks of other turbines according to the frequency component of each turbine, and determine the compensation speed according to the loss power allocated to each turbine, so as to adjust the electromagnetic braking torque of the turbine and stabilize the frequency of the AC power during the maintenance period;

[0011] The maintenance evaluation module is used to detect the working efficiency and efficiency reduction rate of the turbine within a preset time after the turbine is overhauled and resumed operation, and compare them with the data before the maintenance, so as to give an evaluation of the maintenance effect.

[0012] Further, the efficiency evaluation module includes: a motor output unit and an efficiency drawing unit;

[0013] The motor output unit is used to obtain the working data of the water turbine, and the working data includes the water pressure of the reservoir and the speed of the water turbine to calculate the expected power generation of the hydroelectric unit;

[0014] The efficiency drawing unit is used to calculate the power generation efficiency of the water turbine and draw a function of the change of the power generation efficiency of the water turbine over time.

[0015] Further, the task management module includes: a maintenance occurrence unit, a task scheduling unit and a maintenance recording unit;

[0016] The maintenance generating unit is used to calculate the time when the turbine needs maintenance according to the efficiency reduction rate of the turbine;

[0017] The task scheduling unit is used to generate a maintenance task scheduling table according to the maintenance time of each turbine;

[0018] The maintenance recording unit is used to calculate the maintenance task duration according to the maintenance times of adjacent turbines on the maintenance task schedule.

[0019] Furthermore, the frequency tracing module includes: a power sampling unit and a phase corresponding unit;

[0020] The power sampling unit is used to obtain the frequency of the output current using an ammeter, and obtain the frequency of the turbine according to the rotation speed of the turbine;

[0021] The phase corresponding unit is used to calculate the amplitude of the output current of each turbine according to the frequency and the total output current of the turbine.

[0022] Further, the loss compensation module includes: a power fading unit, a component compensation unit and a braking torque unit;

[0023] The power fading unit is used to calculate the power loss of output electric energy during the maintenance process according to the frequency component of the turbine to be repaired;

[0024] The component compensation unit is used to distribute the lost power to the working tasks of other turbines according to the frequency components of each turbine;

[0025] The braking torque unit is used to adjust the electromagnetic braking torque of the turbine to stabilize the frequency of the alternating current during maintenance.

[0026] Further, the maintenance evaluation module includes: an efficiency comparison unit and an evaluation generation unit;

[0027] The efficiency comparison unit is used to detect the power generation efficiency of the turbine after the maintenance is completed;

[0028] The evaluation generation unit is used to evaluate the effect of the maintenance according to the power generation efficiency of the turbine before and after the maintenance.

[0029] A task intelligent management and control method for maintenance of hydropower units, comprising the following steps:

[0030] Step S1. Calculate the expected power generation of the turbine according to the working data of the hydropower unit, calculate the actual power generation of the turbine according to the output current data, obtain the power generation efficiency of the turbine after dividing, and generate a first function of power generation efficiency and time;

[0031] Step S2. According to the reading and derivative of the first function at the current moment, the moment when the value of the first function drops to the threshold is predicted as the maintenance moment of the turbine. According to the maintenance moment of each turbine, the maintenance task schedule is output, and the maintenance duration is determined according to the task schedule;

[0032] Step S3. At the time of maintenance, the output power of the turbine under maintenance is separated from the total output power, and the lost power is distributed to the remaining turbines according to the frequency and phase of the output power of the remaining turbines in the total output power of the hydropower unit;

[0033] Step S4. The remaining turbines calculate the compensating torque according to the allocated power loss and maintenance time, and adjust the electromagnetic braking torque of the turbine according to the power loss and the hardware parameters of the turbine, so that the power increase of the hydropower unit after adjustment is equal to the power loss;

[0034] Step S5. After the maintenance is completed, the derivative of the first function is detected again at every preset period, and the evaluation of the maintenance result is output according to the difference between the derivatives of the first function before and after the maintenance and the maintenance duration;

[0035] Step S6. Build a ledger database to record maintenance operations on the turbine before, during and after maintenance, and add an evaluation of the maintenance behavior after the maintenance record. Send the maintenance records in the ledger database to the technical supervision department at regular intervals.

[0036] Further, step S1 includes:

[0037] Step S11. Calculate the expected power generation of the turbine according to the working data of the turbine group, the working data including: water reservoir flow, water level and turbine speed, the expected power generation is calculated as follows: Q0 = a g R H v / 2π, where Q0 is the expected power generation, a is the density of water, g is the acceleration of gravity, R is the water reservoir flow, H is the water level, and v is the turbine speed;

[0038] Step S12. Differentially adjust the rotation speed of each turbine, perform frequency domain separation on the total output power of the turbine according to the frequency represented by the rotation speed of each turbine, obtain the actual power and actual power generation of each turbine, and calculate the power generation efficiency j of the turbine, where j=Q / Q0, where Q represents the actual power generation of the turbine;

[0039] Step S13. Continuously execute steps S11 and S12 on the turbine to generate a first function F(t) of the turbine power generation efficiency varying with time, wherein t represents time.

[0040] Further, step S2 includes:

[0041] Step S21. Calculate the derivative F of the first function F(t) ’ (t), predict the moment when the first function value drops to the threshold according to the following formula:

[0042]

[0043] Wherein, tc represents the moment when the first function value drops to the threshold, C represents the preset threshold, and t0 represents the current moment;

[0044] Step S22. According to the method of step S21, the tc values ​​of all turbines in the hydroelectric generator set are calculated, and the time when the first function value drops to the threshold is used as the maintenance time of the turbine. According to the maintenance time and the turbine number, a maintenance task schedule is generated;

[0045] Step S23. According to the maintenance task table, the difference between the maintenance times of two adjacent turbines is used as the maximum maintenance time of the previous turbine, and the maintenance time of the last turbine in the maintenance task schedule is used as the update time. When the time update time is reached, repeat steps S11-S21 to update the maintenance task schedule.

[0046] This step can calculate the power generation efficiency of the turbine according to the water pressure of the reservoir, the turbine speed and the motor output power, so as to determine the time when the working efficiency of each turbine drops to the threshold, generate a task schedule according to the maintenance time, and adjust the working condition of the turbine or maintain the equipment in time.

[0047] Further, step S3 includes:

[0048] Step S31. Before the turbine is overhauled, the frequency f of the power transmission component corresponding to the turbine is obtained from the rotation speed of the turbine to be overhauled, where f=v / 2π. The total output power of the hydroelectric unit is transformed in the frequency domain, the component with the frequency f is separated and inversely transformed, and the function G(t) of the power loss of the hydroelectric unit and time after the turbine to be overhauled stops is obtained;

[0049] Step S32. Number the remaining turbines except the turbine to be repaired, and obtain the frequency of the corresponding power transmission component according to the set speed of the turbine, which is recorded as a set D = {f1, f2, ..., fm(t), ..., fn}, where n represents the number of the remaining turbines, and fm represents the frequency of the power transmission component corresponding to the turbine numbered m;

[0050] Step S33. Decompose the function G(t) according to the frequency of each element in the set D, and obtain the corresponding component of each frequency, which is recorded as the compensation power of each turbine. The set of compensation power is {g1(t), g2(t), ..., gm(t), ..., gn(t)}, where gm(t) represents the component of the function G(t) at the frequency fm.

[0051] Further, step S4 includes:

[0052] Step S41. Calculate the compensating rotation torque of the turbine m according to the following formula:

[0053]

[0054] Wherein, Km(t) represents the compensation torque of turbine m as a function of time, Pm(t) represents the output power of turbine m, and vm represents the speed of turbine m;

[0055] Step S42. Calculate the adjustment function of the electromagnetic braking torque according to the compensating rotation torque and the rotor diameter of the turbine, so that the power increase of the hydropower unit after adjustment is equal to the power loss, and the adjustment function Hm(t)=H0-Km(t) / L, wherein Hm is the adjustment function of turbine m, H0 represents the current electromagnetic braking torque of the turbine rotor, and L represents the diameter of the turbine rotor;

[0056] Step S43. Traverse all possible values ​​of m to obtain the regulation function of each turbine. During the maintenance process, the electromagnetic braking torque of the turbine is adjusted in real time according to the regulation function.

[0057] Further, step S5 includes:

[0058] Step S51. After the maintenance is completed, the derivative of the first function of the turbine after maintenance is calculated according to the method of steps S1-S2 at every preset period, and the calculation result is recorded as {F1 ’ (t),F2 ’ (t),…,Fx ’ (t)}, where x represents the number of cycles, Fx ’ (t) represents the derivative of the first function of the turbine after the end of the xth cycle;

[0059] Step S52. Evaluate the effect of turbine maintenance according to the following formula to obtain the turbine maintenance coefficient:

[0060]

[0061] Where U represents the maintenance factor of the turbine, T is the preset cycle, and i is the cycle count;

[0062] Step S53. The maintenance coefficient of the turbine is stored in the database, recorded in the historical maintenance tasks, and output to the database manager before the next maintenance begins;

[0063] Furthermore, in step S6, a ledger database is constructed to record maintenance preparation, maintenance implementation, maintenance summary, maintenance evaluation, technical supervision and special project information.

[0064] By managing the maintenance tasks of hydropower units, the maintenance process can be fully centered on safety and quality, and unit maintenance tasks, technical supervision business and special project business can be better carried out, thereby achieving the goal of excellent unit maintenance.

[0065] Compared with the prior art, the beneficial effects achieved by the present invention are:

[0066] 1. The present invention can calculate the power generation efficiency of the turbine according to the water pressure of the reservoir, the speed of the turbine and the output power of the motor, thereby determining the time when the working efficiency of each turbine drops to a threshold value, and generating a task schedule according to the maintenance time, so as to timely adjust the working condition of the turbine or maintain the equipment to improve the performance and efficiency, and at the same time reasonably arrange the maintenance tasks to ensure the long-term stable operation of the hydropower unit.

[0067] 2. The present invention can sample the AC frequency signal before carrying out a task, calculate the frequency component of the excitation current from each turbine in the AC according to the frequency sample and the rotational speed of the turbine corresponding to the task, and obtain the power loss during maintenance. The energy loss during maintenance can be evaluated, and the impact of maintenance behavior on the power grid can be minimized.

[0068] 3. The present invention can distribute the power loss according to the frequency component, adjust the electromagnetic braking torque of the turbine, stabilize the frequency of the AC power during the maintenance, and evaluate the maintenance effect according to the efficiency drop function after the maintenance. It can find out the deficiencies and problems in the maintenance, provide data support for improving and optimizing the maintenance plan, and improve the maintenance quality and efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0069] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0070] Figure 1 It is a structural schematic diagram of a task intelligent management and control system for maintenance of hydropower units according to the present invention;

[0071] Figure 2 It is a schematic diagram of the steps of a task intelligent management and control method for maintenance of hydropower units according to the present invention. DETAILED DESCRIPTION

[0072] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0073] See also Figure 1 ,The present invention provides a technical solution: a task intelligent management and control system for maintenance of hydropower units, including: an efficiency evaluation module, a task management module, a frequency tracing module, a loss compensation module and a maintenance evaluation module;

[0074] The efficiency evaluation module is used to obtain the working data of the hydropower unit by using the sensor, calculate the expected power generation of the hydropower unit according to the water pressure of the reservoir and the speed of the turbine, divide it by the time power generation of the turbine, calculate the power generation efficiency of the turbine, and draw a function of the change of the power generation efficiency of the turbine over time;

[0075] The efficiency evaluation module includes: a motor output unit and an efficiency drawing unit;

[0076] The motor output unit is used to obtain the working data of the water turbine, and the working data includes the water pressure of the reservoir and the speed of the water turbine to calculate the expected power generation of the hydroelectric unit;

[0077] The efficiency drawing unit is used to calculate the power generation efficiency of the water turbine and draw a function of the change of the power generation efficiency of the water turbine over time.

[0078] The task management module is used to evaluate the efficiency drop rate of the turbine according to the derivative of the function of the change of the power generation efficiency of the turbine over time, calculate the time when the working efficiency of each turbine drops to the threshold value according to the efficiency drop rate and the current efficiency, record it as the maintenance time of the turbine, generate the maintenance task arrangement according to the maintenance time of each turbine, and determine the maintenance task duration according to the interval between the maintenance times of two turbines;

[0079] The task management module includes: a maintenance occurrence unit, a task scheduling unit and a maintenance recording unit;

[0080] The maintenance generating unit is used to calculate the time when the turbine needs maintenance according to the efficiency reduction rate of the turbine;

[0081] The task scheduling unit is used to generate a maintenance task scheduling table according to the maintenance time of each turbine;

[0082] The maintenance recording unit is used to calculate the maintenance task duration according to the maintenance times of adjacent turbines on the maintenance task schedule.

[0083] The frequency tracing module is used to sample the AC frequency signal, calculate the frequency component of the excitation current of each turbine in the AC according to the frequency sample and the speed of the turbine corresponding to the task, and make the frequency of the component correspond to the number of the turbine one by one;

[0084] The frequency tracing module includes: a power sampling unit and a phase corresponding unit;

[0085] The power sampling unit is used to obtain the frequency of the output current using an ammeter, and obtain the frequency of the turbine according to the rotation speed of the turbine;

[0086] The phase corresponding unit is used to calculate the amplitude of the output current of each turbine according to the frequency and the total output current of the turbine.

[0087] The loss compensation module is used to calculate the loss power of the output electric energy during the maintenance process according to the maintenance task duration and the frequency component of the turbine to be repaired during the maintenance of the turbine, distribute the loss power to the working tasks of other turbines according to the frequency component of each turbine, and determine the compensation speed according to the loss power allocated to each turbine, so as to adjust the electromagnetic braking torque of the turbine and stabilize the frequency of the AC power during the maintenance period;

[0088] The loss compensation module includes: a power fading unit, a component compensation unit and a braking torque unit;

[0089] The power fading unit is used to calculate the power loss of output electric energy during the maintenance process according to the frequency component of the turbine to be repaired;

[0090] The component compensation unit is used to distribute the lost power to the working tasks of other turbines according to the frequency components of each turbine;

[0091] The braking torque unit is used to adjust the electromagnetic braking torque of the turbine to stabilize the frequency of the alternating current during maintenance.

[0092] The maintenance evaluation module is used to detect the working efficiency and efficiency reduction rate of the turbine within a preset time after the turbine is overhauled and resumed operation, and compare them with the data before the maintenance, so as to give an evaluation of the maintenance effect.

[0093] The maintenance evaluation module includes: an efficiency comparison unit and an evaluation generation unit;

[0094] The efficiency comparison unit is used to detect the power generation efficiency of the turbine after the maintenance is completed;

[0095] The evaluation generation unit is used to evaluate the effect of the maintenance according to the power generation efficiency of the turbine before and after the maintenance.

[0096] like Figure 2 As shown, a task intelligent management and control method for hydropower unit maintenance includes the following steps:

[0097] Step S1. Calculate the expected power generation of the turbine according to the working data of the hydropower unit, calculate the actual power generation of the turbine according to the output current data, obtain the power generation efficiency of the turbine after dividing, and generate a first function of power generation efficiency and time;

[0098] Step S1 includes:

[0099] Step S11. Calculate the expected power generation of the turbine according to the working data of the turbine group, the working data including: water reservoir flow, water level and turbine speed, the expected power generation is calculated as follows: Q0 = a g R H v / 2π, where Q0 is the expected power generation, a is the density of water, g is the acceleration of gravity, R is the water reservoir flow, H is the water level, and v is the turbine speed;

[0100] Step S12. Differentially adjust the rotation speed of each turbine, perform frequency domain separation on the total output power of the turbine according to the frequency represented by the rotation speed of each turbine, obtain the actual power and actual power generation of each turbine, and calculate the power generation efficiency j of the turbine, where j=Q / Q0, where Q represents the actual power generation of the turbine;

[0101] Step S13. Continuously execute steps S11 and S12 on the turbine to generate a first function F(t) of the turbine power generation efficiency varying with time, wherein t represents time.

[0102] Step S2. According to the reading and derivative of the first function at the current moment, the moment when the value of the first function drops to the threshold is predicted as the maintenance moment of the turbine. According to the maintenance moment of each turbine, the maintenance task schedule is output, and the maintenance duration is determined according to the task schedule;

[0103] Step S2 includes:

[0104] Step S21. Calculate the derivative F of the first function F(t) ’ (t), predict the moment when the first function value drops to the threshold according to the following formula:

[0105]

[0106] Wherein, tc represents the moment when the first function value drops to the threshold, C represents the preset threshold, and t0 represents the current moment;

[0107] Step S22. According to the method of step S21, the tc values ​​of all turbines in the hydroelectric generator set are calculated, and the time when the first function value drops to the threshold is used as the maintenance time of the turbine. According to the maintenance time and the turbine number, a maintenance task schedule is generated;

[0108] Step S23. According to the maintenance task table, the difference between the maintenance times of two adjacent turbines is used as the maximum maintenance time of the previous turbine, and the maintenance time of the last turbine in the maintenance task schedule is used as the update time. When the time update time is reached, repeat steps S11-S21 to update the maintenance task schedule.

[0109] Step S3. At the time of maintenance, the output power of the turbine under maintenance is separated from the total output power, and the lost power is distributed to the remaining turbines according to the frequency and phase of the output power of the remaining turbines in the total output power of the hydropower unit;

[0110] Step S3 includes:

[0111] Step S31. Before the turbine is overhauled, the frequency f of the power transmission component corresponding to the turbine is obtained from the rotation speed of the turbine to be overhauled, where f=v / 2π. The total output power of the hydroelectric unit is transformed in the frequency domain, the component with the frequency f is separated and inversely transformed, and the function G(t) of the power loss of the hydroelectric unit and time after the turbine to be overhauled stops is obtained;

[0112] Step S32. Number the remaining turbines except the turbine to be repaired, and obtain the frequency of the corresponding power transmission component according to the set speed of the turbine, which is recorded as a set D = {f1, f2, ..., fm(t), ..., fn}, where n represents the number of the remaining turbines, and fm represents the frequency of the power transmission component corresponding to the turbine numbered m;

[0113] Step S33. Decompose the function G(t) according to the frequency of each element in the set D, and obtain the corresponding component of each frequency, which is recorded as the compensation power of each turbine. The set of compensation power is {g1(t), g2(t), ..., gm(t), ..., gn(t)}, where gm(t) represents the component of the function G(t) at the frequency fm.

[0114] Step S4. The remaining turbines calculate the compensating torque according to the allocated power loss and maintenance time, and adjust the electromagnetic braking torque of the turbine according to the power loss and the hardware parameters of the turbine, so that the power increase of the hydropower unit after adjustment is equal to the power loss;

[0115] Step S4 includes:

[0116] Step S41. Calculate the compensating rotation torque of the turbine m according to the following formula:

[0117]

[0118] Wherein, Km(t) represents the compensation torque of turbine m as a function of time, Pm(t) represents the output power of turbine m, and vm represents the speed of turbine m;

[0119] Step S42. Calculate the adjustment function of the electromagnetic braking torque according to the compensating rotation torque and the rotor diameter of the turbine, so that the power increase of the hydropower unit after adjustment is equal to the power loss, and the adjustment function Hm(t)=H0-Km(t) / L, wherein Hm is the adjustment function of turbine m, H0 represents the current electromagnetic braking torque of the turbine rotor, and L represents the diameter of the turbine rotor;

[0120] Step S43. Traverse all possible values ​​of m to obtain the regulation function of each turbine. During the maintenance process, the electromagnetic braking torque of the turbine is adjusted in real time according to the regulation function.

[0121] Step S5. After the maintenance is completed, the derivative of the first function is detected again at every preset period, and an evaluation of the maintenance result is output based on the difference between the derivatives of the first function before and after the maintenance and the maintenance duration.

[0122] Step S5 includes:

[0123] Step S51. After the maintenance is completed, the derivative of the first function of the turbine after maintenance is calculated according to the method of steps S1-S2 at every preset period, and the calculation result is recorded as {F1 ’ (t),F2 ’ (t),…,Fx ’ (t)}, where x represents the number of cycles, Fx ’ (t) represents the derivative of the first function of the turbine after the end of the xth cycle;

[0124] Step S52. Evaluate the effect of turbine maintenance according to the following formula to obtain the turbine maintenance coefficient:

[0125]

[0126] Where U represents the maintenance factor of the turbine, T is the preset cycle, and i is the cycle count;

[0127] Step S53. Store the maintenance coefficient of the turbine into the database, record it in the historical maintenance tasks, and output it to the database manager before the next maintenance begins.

[0128] Step S6. Build a ledger database to record maintenance operations on the turbine before, during and after maintenance, and add an evaluation of the maintenance behavior after the maintenance record. Send the maintenance records in the ledger database to the technical supervision department at regular intervals.

[0129] Example: There are three turbines in the hydroelectric unit, and the speeds are set to 30 degrees / second, 60 degrees / second and 90 degrees / second respectively. The flow rate of the reservoir is 10m 3 / s, water storage height 10m, then the expected power generation of the turbines are 83KW, 166KW and 249KW respectively, the total power generation of the hydropower unit is 400KW, the actual power generation allocated to each turbine is 66KW, 133KW and 201KW, and the power generation efficiency of the three turbines is 79%, 80% and 81% respectively;

[0130] It is stipulated that maintenance shall be carried out when the power generation efficiency drops to 75%. According to the derivative of power generation efficiency, the maintenance time of the three turbines when the power generation efficiency drops to 75% is calculated to be 100 hours, 120 hours and 90 hours respectively. Then the generated schedule is: turbine 3, maintenance time is 10 hours, turbine 1, maintenance time is 20 hours, turbine 3, maintenance time is 90 hours. The maintenance task schedule is stored in the database and output.

[0131] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0132] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A task intelligent management and control method for maintenance of hydropower units, characterized in that: The method comprises the following steps: Step S1. Calculate the expected power generation of the turbine according to the working data of the hydropower unit, calculate the actual power generation of the turbine according to the output current data, obtain the power generation efficiency of the turbine after dividing, and generate a first function of power generation efficiency and time; Step S2. According to the reading and derivative of the first function at the current moment, the moment when the value of the first function drops to the threshold is predicted as the maintenance moment of the turbine. According to the maintenance moment of each turbine, the maintenance task schedule is output, and the maintenance duration is determined according to the task schedule; Step S3. At the time of maintenance, the output power of the turbine under maintenance is separated from the total output power, and the lost power is distributed to the remaining turbines according to the frequency and phase of the output power of the remaining turbines in the total output power of the hydropower unit; Step S4. The remaining turbines calculate the compensating torque according to the allocated power loss and maintenance time, and adjust the electromagnetic braking torque of the turbine according to the power loss and the hardware parameters of the turbine, so that the power increase of the hydropower unit after adjustment is equal to the power loss; Step S5. After the maintenance is completed, the derivative of the first function is detected again at every preset period, and the evaluation of the maintenance result is output according to the difference between the derivatives of the first function before and after the maintenance and the maintenance duration; Step S6. Build a ledger database to record maintenance operations on the turbine before, during and after maintenance, and add an evaluation of the maintenance behavior after the maintenance record. Send the maintenance records in the ledger database to the technical supervision department at regular intervals.

2. According to claim 1, a task intelligent management and control method for maintenance of hydropower units is characterized by: Step S1 includes: Step S11. Calculate the expected power generation of the turbine according to the working data of the turbine group, the working data including: water reservoir flow, water level and turbine speed, the expected power generation is calculated as follows: Q0 = a g R H v / 2π, where Q0 is the expected power generation, a is the density of water, g is the acceleration of gravity, R is the water reservoir flow, H is the water level, and v is the turbine speed; Step S12. Differentially adjust the rotation speed of each turbine, perform frequency domain separation on the total output power of the turbine according to the frequency represented by the rotation speed of each turbine, obtain the actual power and actual power generation of each turbine, and calculate the power generation efficiency j of the turbine, where j=Q / Q0, where Q represents the actual power generation of the turbine; Step S13. Continuously perform steps S11 and S12 on the turbine to generate a first function F(t) of the turbine power generation efficiency changing with time, where t represents time; Step S2 includes: Step S21. Calculate the derivative F of the first function F(t) ’ (t), predict the moment when the first function value drops to the threshold according to the following formula: Wherein, tc represents the moment when the first function value drops to the threshold, C represents the preset threshold, and t0 represents the current moment; Step S22. According to the method of step S21, the tc values ​​of all turbines in the hydroelectric generator set are calculated, and the time when the first function value drops to the threshold is used as the maintenance time of the turbine. According to the maintenance time and the turbine number, a maintenance task schedule is generated; Step S23. According to the maintenance task table, the difference between the maintenance times of two adjacent turbines is used as the maximum maintenance time of the previous turbine, and the maintenance time of the last turbine in the maintenance task schedule is used as the update time. When the time update time is reached, repeat steps S11-S21 to update the maintenance task schedule.

3. The method for intelligent task control for maintenance of hydropower units according to claim 2 is characterized in that: Step S3 includes: Step S31. Before the turbine is overhauled, the frequency f of the power transmission component corresponding to the turbine is obtained from the rotation speed of the turbine to be overhauled, where f=v / 2π. The total output power of the hydroelectric unit is transformed in the frequency domain, the component with the frequency f is separated and inversely transformed, and the function G(t) of the power loss of the hydroelectric unit and time after the turbine to be overhauled stops is obtained; Step S32. Number the remaining turbines except the turbine to be repaired, and obtain the frequency of the corresponding power transmission component according to the set speed of the turbine, which is recorded as a set D = {f1, f2, ..., fm(t), ..., fn}, where n represents the number of the remaining turbines, and fm represents the frequency of the power transmission component corresponding to the turbine numbered m; Step S33. Decompose the function G(t) according to the frequency of each element in the set D, and obtain the corresponding component of each frequency, which is recorded as the compensation power of each turbine. The set of compensation power is {g1(t), g2(t), ..., gm(t), ..., gn(t)}, where gm(t) represents the component of the function G(t) at the frequency fm.

4. The method for intelligent task control for maintenance of hydropower units according to claim 3 is characterized by: Step S4 includes: Step S41. Calculate the compensating rotation torque of the turbine m according to the following formula: Wherein, Km(t) represents the compensation torque of turbine m as a function of time, Pm(t) represents the output power of turbine m, and vm represents the speed of turbine m; Step S42. Calculate the adjustment function of the electromagnetic braking torque according to the compensating rotation torque and the rotor diameter of the turbine, so that the power increase of the hydropower unit after adjustment is equal to the power loss, and the adjustment function Hm(t)=H0-Km(t) / L, wherein Hm is the adjustment function of turbine m, H0 represents the current electromagnetic braking torque of the turbine rotor, and L represents the diameter of the turbine rotor; Step S43. Traverse all possible values ​​of m to obtain the regulation function of each turbine. During the maintenance process, the electromagnetic braking torque of the turbine is adjusted in real time according to the regulation function.

5. The method for intelligent task control for maintenance of hydropower units according to claim 4 is characterized by: Step S5 includes: Step S51. After the maintenance is completed, the derivative of the first function of the turbine after maintenance is calculated according to the method of steps S1-S2 at every preset period, and the calculation result is recorded as {F1 ’ (t),F2 ’ (t),…,Fx ’ (t)}, where x represents the number of cycles, Fx ’ (t) represents the derivative of the first function of the turbine after the end of the xth cycle; Step S52. Evaluate the effect of turbine maintenance according to the following formula to obtain the turbine maintenance coefficient: Where U represents the maintenance factor of the turbine, T is the preset cycle, and i is the cycle count; Step S53. Store the maintenance coefficient of the turbine into the database, record it in the historical maintenance tasks, and output it to the database manager before the next maintenance begins.

6. A task intelligent management and control system for hydropower unit maintenance, characterized in that: The system includes the following modules: efficiency evaluation module, task management module, frequency tracing module, loss compensation module and maintenance evaluation module; The efficiency evaluation module is used to obtain the working data of the hydropower unit by using the sensor, calculate the expected power generation of the hydropower unit according to the water pressure of the reservoir and the speed of the turbine, divide it by the time power generation of the turbine, calculate the power generation efficiency of the turbine, and draw a function of the change of the power generation efficiency of the turbine over time; The task management module is used to evaluate the efficiency drop rate of the turbine according to the derivative of the function of the change of the power generation efficiency of the turbine over time, calculate the time when the working efficiency of each turbine drops to the threshold value according to the efficiency drop rate and the current efficiency, record it as the maintenance time of the turbine, generate the maintenance task arrangement according to the maintenance time of each turbine, and determine the maintenance task duration according to the interval between the maintenance times of two turbines; The frequency tracing module is used to sample the AC frequency signal, calculate the frequency component of the excitation current of each turbine in the AC according to the frequency sample and the speed of the turbine corresponding to the task, and make the frequency of the component correspond to the number of the turbine one by one; The loss compensation module is used to calculate the loss power of the output electric energy during the maintenance process according to the maintenance task duration and the frequency component of the turbine to be repaired during the maintenance of the turbine, distribute the loss power to the working tasks of other turbines according to the frequency component of each turbine, and determine the compensation speed according to the loss power allocated to each turbine, so as to adjust the electromagnetic braking torque of the turbine and stabilize the frequency of the AC power during the maintenance period; The maintenance evaluation module is used to detect the working efficiency and efficiency reduction rate of the turbine within a preset time after the turbine is overhauled and resumed operation, and compare them with the data before the maintenance, so as to give an evaluation of the maintenance effect.

7. The task intelligent management and control system for maintenance of hydropower units according to claim 6 is characterized by: The efficiency evaluation module includes: a motor output unit and an efficiency drawing unit; The motor output unit is used to obtain the working data of the water turbine, and the working data includes the water pressure of the reservoir and the speed of the water turbine to calculate the expected power generation of the hydroelectric unit; The efficiency drawing unit is used to calculate the power generation efficiency of the water turbine and draw a function of the change of the power generation efficiency of the water turbine over time.

8. The task intelligent management and control system for maintenance of hydropower units according to claim 7 is characterized by: The task management module includes: a maintenance occurrence unit, a task scheduling unit and a maintenance recording unit; The maintenance generating unit is used to calculate the time when the turbine needs maintenance according to the efficiency reduction rate of the turbine; The task scheduling unit is used to generate a maintenance task scheduling table according to the maintenance time of each turbine; The maintenance recording unit is used to calculate the maintenance task duration according to the maintenance times of adjacent turbines on the maintenance task schedule.

9. The task intelligent management and control system for maintenance of hydropower units according to claim 8 is characterized by: The frequency tracing module includes: a power sampling unit and a phase corresponding unit; The power sampling unit is used to obtain the frequency of the output current using an ammeter, and obtain the frequency of the turbine according to the rotation speed of the turbine; The phase corresponding unit is used to calculate the amplitude of the output current of each turbine according to the frequency and total output current of the turbine; The loss compensation module includes: a power fading unit, a component compensation unit and a braking torque unit; The power fading unit is used to calculate the power loss of output electric energy during the maintenance process according to the frequency component of the turbine to be repaired; The component compensation unit is used to distribute the lost power to the working tasks of other water turbines according to the frequency components of each water turbine.

10. The task intelligent management and control system for maintenance of hydropower units according to claim 9 is characterized in that: The maintenance evaluation module includes: an efficiency comparison unit and an evaluation generation unit; The efficiency comparison unit is used to detect the power generation efficiency of the turbine after the maintenance is completed; The evaluation generation unit is used to evaluate the effect of the maintenance according to the power generation efficiency of the turbine before and after the maintenance.

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