Ultra-low frequency oscillation suppression method, device and equipment for hydroelectric generating set and medium

Abstract

The invention relates to the technical field of hydroelectric generating set operation, and discloses a hydroelectric generating set ultra-low frequency oscillation suppression method, device, equipment and medium. Rotor motion data sets of a plurality of hydroelectric generating sets are firstly obtained, and the operation state of each hydroelectric generating set can be comprehensively known; and secondly, the mechanical power of the wide-range rotating speed change rate can be fitted through the target mechanical power relational expression, and the mechanical power of the hydroelectric generating set can be represented more accurately. And the oscillation energy of the speed regulation system can be calculated more accurately in combination with the oscillation energy relational expression of the speed regulation controller. And finally, the plurality of hydroelectric generating units are sorted according to the plurality of oscillation energy values, and which hydroelectric generating units have the ultra-low frequency oscillation problem can be quickly determined. And finally, the ultralow-frequency oscillation of the hydroelectric generating set is suppressed by using the stored energy, so that the coordination problem of the primary frequency modulation performance and the ultralow-frequency oscillation suppression of the hydroelectric generating set can be effectively solved, and a new technical means is provided for solving the ultralow-frequency oscillation problem.

Description

Technical Field

[0001] The present invention relates to the technical field of operation of hydropower units, and in particular to a method, device, equipment and medium for suppressing ultra-low frequency oscillation of a hydropower unit. Background Art

[0002] Ultra-low frequency oscillation is usually caused by the rapid action of the primary frequency regulation of the turbine speed control system and the water hammer effect of the turbine. The traditional low-frequency oscillation analysis method is no longer suitable for ultra-low frequency oscillation. In the ultra-low frequency oscillation analysis, due to the long-term and large-scale changes in the unit oscillation frequency, electrical power cannot be directly used to replace mechanical power in accurate and quantitative analysis. A more accurate method is to use mechanical power for quantitative analysis.

[0003] However, the mechanical power of the generator set cannot be measured directly. In engineering, the mechanical power fitting value is generally calculated by measuring the generator speed and electromagnetic power data, but the boundary condition is usually limited to the case where the speed does not change much. Furthermore, the commonly used ultra-low frequency oscillation suppression measures have reduced the primary frequency regulation capability of the hydropower unit to a certain extent, which will weaken the system's rapid frequency regulation capability. Therefore, it is necessary to study suppression measures that take into account both the primary frequency regulation performance and the ultra-low frequency oscillation suppression effect. Summary of the invention

[0004] In view of this, the present invention provides a method, device, equipment and medium for suppressing ultra-low frequency oscillation of a hydropower unit, so as to solve the problem that the boundary condition when calculating the mechanical power fitting value is usually limited to the situation where the speed change is not large, and the problem that the primary frequency regulation performance and the ultra-low frequency oscillation suppression effect cannot be taken into account when analyzing the ultra-low frequency oscillation of the unit based on the mechanical power fitting value.

[0005] In a first aspect, the present invention provides a method for suppressing ultra-low frequency oscillation of a hydropower unit, the method comprising:

[0006] Obtain rotor motion data sets of multiple hydropower units; based on the rotor motion data sets, multiple oscillation energy values ​​of the speed control systems in the multiple hydropower units are obtained through calculation of the target mechanical power relationship and the oscillation energy relationship of the speed controller, and the target mechanical power relationship is used to fit the mechanical power of a wide range of speed change rates; use the multiple oscillation energy values ​​to sort the multiple hydropower units and determine the target hydropower units that have ultra-low frequency oscillations; use the energy storage system to suppress the ultra-low frequency oscillation of the target hydropower unit and obtain the ultra-low frequency oscillation suppression result.

[0007] The method for suppressing ultra-low frequency oscillation of a hydropower unit provided by the present invention first obtains the rotor motion data set of multiple hydropower units, so as to fully understand the operating status of each hydropower unit. Secondly, the mechanical power with a wide range of speed change rate can be fitted through the target mechanical power relationship, which can more accurately characterize the mechanical power of the hydropower unit. Furthermore, combined with the oscillation energy relationship of the speed controller, the oscillation energy of the speed regulation system can be more accurately calculated. Finally, by sorting multiple hydropower units according to multiple oscillation energy values, it is possible to quickly determine which hydropower units have ultra-low frequency oscillation problems, providing a clear target for targeted suppression measures. Finally, using energy storage to suppress ultra-low frequency oscillations of hydropower units can effectively solve the coordination problem of the primary frequency regulation performance of the hydropower unit and the ultra-low frequency oscillation suppression, and provide a new technical means for solving the ultra-low frequency oscillation problem.

[0008] In an optional embodiment, the method further includes:

[0009] The initial mechanical power relationship and the speed change rate of the hydropower unit are obtained; a preset first distribution coefficient and a preset second distribution coefficient are determined using the speed change rate; based on the preset first distribution coefficient and the preset second distribution coefficient, the initial mechanical power relationship is converted to obtain a target mechanical power relationship.

[0010] The method for suppressing ultra-low frequency oscillation of a hydropower unit provided by the present invention can transform the initial mechanical power relationship by considering the speed change rate and introducing a distribution coefficient, so that the target mechanical power relationship can adapt to a wide range of speed change rates, so that the mechanical power can be effectively fitted under different working conditions, thereby more accurately characterizing the mechanical power of the hydropower unit.

[0011] In an optional implementation, obtaining the initial mechanical power relationship of the hydropower unit includes:

[0012] Obtain the rotor motion equation of the hydropower unit; obtain the electromagnetic power relationship and the electromagnetic torque relationship of the hydropower unit; input the electromagnetic power relationship and the electromagnetic torque relationship into the rotor motion equation of the hydropower unit to obtain the initial mechanical power relationship of the hydropower unit.

[0013] In an optional implementation, the target hydropower unit is subjected to ultra-low frequency oscillation suppression using an energy storage system to obtain an ultra-low frequency oscillation suppression result, including:

[0014] Obtain the objective function and the initial active output of the energy storage system; based on the objective function and the energy storage power constraint set, use the particle swarm algorithm to optimize the initial active output to obtain the target active output; based on the target active output, use the energy storage system to suppress the ultra-low frequency oscillation of the target hydropower unit to obtain the ultra-low frequency oscillation suppression result.

[0015] The method for suppressing ultra-low frequency oscillation of a hydropower unit provided by the present invention can optimize the active output of the energy storage system through a particle swarm algorithm under the control of the objective function and the constraints of the energy storage power constraint condition set, and then obtain the target energy storage output that satisfies the suppression effect through optimization. Finally, the energy storage system can effectively suppress the ultra-low frequency oscillation generated by the target hydropower unit according to the target active output, effectively solving the coordination problem between the primary frequency regulation performance of the hydropower unit and the ultra-low frequency oscillation suppression.

[0016] In an optional implementation, obtaining the objective function and the initial active output of the energy storage system includes:

[0017] Obtain the frequency deviation of the target hydropower unit and the energy storage data set of the energy storage system; determine the initial active output and the upper limit of the active output of the energy storage system based on the frequency deviation; calculate the energy storage capacity requirement of the energy storage system based on the energy storage data set; determine the objective function based on the energy storage capacity requirement and the upper limit of the active output.

[0018] The method for suppressing ultra-low frequency oscillation of a hydropower unit provided by the present invention can directly reflect the difference between the current operating state and the standard state of the hydropower unit by obtaining the frequency deviation of the target hydropower unit, and then determine the active output of the energy storage system by the frequency deviation, so that the energy storage system can quickly respond to changes in the hydropower unit. Furthermore, by combining the energy storage capacity demand and the upper limit of the active output to determine the objective function, the objective function can comprehensively consider the performance of the energy storage system and the needs of the hydropower unit, providing support for subsequent optimization.

[0019] In an optional implementation, the energy storage power constraint condition set includes an energy storage maximum charging power constraint condition and an energy storage maximum discharging power constraint condition.

[0020] In a second aspect, the present invention provides a device for suppressing ultra-low frequency oscillation of a hydropower unit, the device comprising:

[0021] The first acquisition module is used to acquire rotor motion data sets of multiple hydropower units; the calculation module is used to obtain multiple oscillation energy values ​​of the speed control system in multiple hydropower units based on the rotor motion data sets through the target mechanical power relationship and the oscillation energy relationship of the speed controller, and the target mechanical power relationship is used to fit the mechanical power with a wide range of speed change rates; the processing module is used to use the multiple oscillation energy values ​​to sort the multiple hydropower units and determine the target hydropower units that have ultra-low frequency oscillations; the suppression module is used to use the energy storage system to suppress the ultra-low frequency oscillation of the target hydropower unit and obtain the ultra-low frequency oscillation suppression result.

[0022] In a third aspect, the present invention provides a computer device, comprising: a memory and a processor, the memory and the processor being communicatively connected to each other, the memory storing computer instructions, and the processor executing the method for suppressing ultra-low frequency oscillation of a hydropower unit according to the first aspect or any corresponding embodiment thereof by executing the computer instructions.

[0023] In a fourth aspect, the present invention provides a computer-readable storage medium having computer instructions stored thereon, the computer instructions being used to enable a computer to execute the method for suppressing ultra-low frequency oscillations of a hydropower unit according to the first aspect or any corresponding embodiment thereof.

[0024] In a fifth aspect, the present invention provides a computer program product, comprising computer instructions for causing a computer to execute the method for suppressing ultra-low frequency oscillation of a hydropower unit according to the first aspect or any corresponding embodiment thereof. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0026] Figure 1 is a schematic flow chart of a method for suppressing ultra-low frequency oscillation of a hydropower unit according to an embodiment of the present invention;

[0027] Figure 2 is a flow chart of another method for suppressing ultra-low frequency oscillation of a hydropower unit according to an embodiment of the present invention;

[0028] Figure 3 is a flow chart of another method for suppressing ultra-low frequency oscillation of a hydropower unit according to an embodiment of the present invention;

[0029] Figure 4 is a schematic diagram of a measure for suppressing ultra-low frequency oscillation by energy storage according to an embodiment of the present invention;

[0030] Figure 5 is a structural block diagram of a device for suppressing ultra-low frequency oscillation of a hydropower unit according to an embodiment of the present invention;

[0031] Figure 6 It is a schematic diagram of the hardware structure of a computer device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0032] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are 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 those skilled in the art without creative work are within the scope of protection of the present invention.

[0033] The embodiment of the present invention provides a method for suppressing ultra-low frequency oscillation of a hydropower unit, which can more accurately characterize the mechanical power of the generator set through a target mechanical power relationship suitable for mechanical power fitting in a wide range of speed change rates. Furthermore, combining energy storage to suppress ultra-low frequency oscillation of the hydropower unit effectively solves the coordination problem of primary frequency regulation performance and ultra-low frequency oscillation suppression of the hydropower unit.

[0034] According to an embodiment of the present invention, an embodiment of a method for suppressing ultra-low frequency oscillations of a hydropower unit is provided. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and although a logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0035] In this embodiment, a method for suppressing ultra-low frequency oscillation of a hydropower unit is provided, which can be used in electronic devices such as computers, mobile phones, tablet computers, etc. Figure 1 is a flow chart of a method for suppressing ultra-low frequency oscillation of a hydropower unit according to an embodiment of the present invention. Figure 1 As shown, the process includes the following steps:

[0036] Step S101, obtaining rotor motion data sets of multiple hydropower units.

[0037] The rotor motion data set is used to characterize the rotor motion of the hydropower unit, and may include: the moment of inertia M of the hydropower unit, the mechanical torque T of the prime mover, n , electromagnetic torque T e , motor shaft rotation angular velocity ω, synchronous angular velocity ω0 and equivalent damping D and other coefficients.

[0038] Step S102, based on the rotor motion data set, multiple oscillation energy values ​​of the speed control systems in multiple hydropower units are obtained through calculation of the target mechanical power relationship and the oscillation energy relationship of the speed control controller.

[0039] The target mechanical power relationship is used to fit the mechanical power with a wide range of speed change rates.

[0040] Furthermore, the oscillation energy relationship of the speed controller is shown in the following relationship (1):

[0041] ΔE os =∫ΔP m Δfdt (1)

[0042] Where: ΔE os Indicates the oscillation energy of the speed controller; ΔP m represents the change in mechanical power of the generator set; Δf represents the change in frequency; P m represents the mechanical power of the hydropower unit; f represents the motor frequency.

[0043] Specifically, the obtained rotor motion data set is input into the target mechanical power relationship to fit the corresponding mechanical power P of the hydropower unit. m .

[0044] Furthermore, the oscillation energy value of the speed control system in each hydropower unit can be calculated by combining the above relationship (1).

[0045] Step S103: sorting the multiple hydropower generating units using the multiple oscillation energy values ​​and determining the target hydropower generating unit that has ultra-low frequency oscillation.

[0046] Firstly, the multiple hydropower generating units are sorted according to the calculated values ​​of multiple oscillation energies.

[0047] Secondly, determine whether the oscillation energy value is greater than zero.

[0048] Then, the positive or negative value of the oscillation energy value reflects the damping properties provided by the speed control system. If the oscillation energy value is negative, that is, the oscillation energy value is less than zero, it means that the damping provided by the speed control system is positive damping. In this case, the hydropower unit is relatively stable, which means that the hydropower unit corresponding to the oscillation energy value does not have ultra-low frequency oscillation.

[0049] Furthermore, if the oscillation energy value is positive, that is, the oscillation energy value is greater than zero, it means that the damping provided by the speed control system is negative damping, that is, the hydropower unit corresponding to the oscillation energy value has an ultra-low frequency oscillation.

[0050] Finally, one or more target hydropower units with ultra-low frequency oscillations can be screened out according to the oscillation energy value, and then targeted measures can be taken to suppress ultra-low frequency oscillations by determining the target hydropower units.

[0051] Step S104: utilizing the energy storage system to suppress ultra-low frequency oscillation of the target hydropower unit to obtain an ultra-low frequency oscillation suppression result.

[0052] Specifically, after determining the target hydropower unit, the energy storage system is connected to the power system where the target hydropower unit is located. The energy storage system can be different types of energy storage devices such as battery energy storage and supercapacitor energy storage.

[0053] Furthermore, the corresponding energy storage system control strategy can be determined according to the operating status of the target hydropower unit and the characteristics of the ultra-low frequency oscillation. For example, the charging and discharging power of the energy storage system can be controlled based on signals such as frequency deviation and power change.

[0054] Furthermore, the energy storage system can quickly respond to the ultra-low frequency oscillation suppression operation of the target hydropower unit according to the corresponding control strategy, and adjust the active power balance of the system by absorbing or releasing power, providing additional damping for the hydropower unit, thereby suppressing the ultra-low frequency oscillation of the target hydropower unit.

[0055] The method for suppressing ultra-low frequency oscillation of a hydropower unit provided in this embodiment first obtains the rotor motion data set of multiple hydropower units, so as to fully understand the operating status of each hydropower unit. Secondly, the mechanical power with a wide range of speed change rates can be fitted through the target mechanical power relationship, which can more accurately characterize the mechanical power of the hydropower unit. Furthermore, combined with the oscillation energy relationship of the speed controller, the oscillation energy of the speed regulation system can be more accurately calculated. Finally, by sorting multiple hydropower units according to multiple oscillation energy values, it is possible to quickly determine which hydropower units have ultra-low frequency oscillation problems, providing a clear target for targeted suppression measures. Finally, using energy storage to suppress ultra-low frequency oscillations of hydropower units can effectively solve the coordination problem of the primary frequency regulation performance of the hydropower unit and the ultra-low frequency oscillation suppression, and provide a new technical means for solving the ultra-low frequency oscillation problem.

[0056] In this embodiment, a method for suppressing ultra-low frequency oscillation of a hydropower unit is provided, which can be used in electronic devices such as computers, mobile phones, tablet computers, etc. Figure 2 is a flow chart of a method for suppressing ultra-low frequency oscillation of a hydropower unit according to an embodiment of the present invention. Figure 2 As shown, the process includes the following steps:

[0057] Step S201, obtain rotor motion data sets of multiple hydropower units. Figure 1 Step S101 of the illustrated embodiment will not be described in detail here.

[0058] Step S202, obtaining the initial mechanical power relationship and speed change rate of the hydropower unit.

[0059] Specifically, the initial mechanical power relationship is used to characterize the mechanical power of the hydropower unit; the speed change rate is used to measure the speed of the hydropower unit's speed change, which can reflect the dynamic characteristics of the hydropower unit during operation. For example, when the hydropower unit is affected by factors such as load changes and speed control system adjustments, the speed will change, and the speed change rate can reflect the system's response speed and stability to these changes.

[0060] In some optional implementations, the initial mechanical power relationship can be obtained by the following steps:

[0061] Step a1, obtaining the rotor motion equation of the hydropower unit.

[0062] Step a2, obtaining the electromagnetic power relationship and electromagnetic torque relationship of the hydropower unit.

[0063] Step a3, inputting the electromagnetic power relational expression and the electromagnetic torque relational expression into the rotor motion equation of the hydropower unit to obtain the initial mechanical power relational expression of the hydropower unit.

[0064] Specifically, the motion equation of the hydropower unit rotor is shown in the following equation (2):

[0065]

[0066] Furthermore, the electromagnetic power relationship of the hydropower unit is expressed as the following relationship (3):

[0067] P e =ωT e (3)

[0068] Where: P e Represents the electromagnetic power of the hydropower unit.

[0069] Furthermore, the electromagnetic torque relationship is expressed as the following relationship (4):

[0070] ω=2πf (4)

[0071] Furthermore, by substituting the above equations (3) and (4) into the above equation (2), the initial mechanical power equation of the hydropower unit can be obtained, as shown in the following equation (5):

[0072]

[0073] Step S203: Determine a preset first allocation coefficient and a preset second allocation coefficient by using the rotation speed change rate.

[0074] Specifically, the changing trends of the preset first allocation coefficient k1 and the preset second allocation coefficient k2 are adapted to the characteristics of the speed change rate of the generator set, as shown in the following relational expression (6):

[0075]

[0076] Wherein: N represents the adjustment factor, which is used to adjust the distribution coefficient according to the speed change Δf of the generator set to adapt to different operating conditions; k1+k2=1.

[0077] Furthermore, the preset first distribution coefficient k1 represents the distribution coefficient when the speed change rate is very small. When the speed change rate is very small, k1=1; when the speed change rate exceeds a certain limit, the preset second distribution coefficient k2 is used. The greater the speed change rate, the closer k2 is to 1.

[0078] Step S204: based on the preset first allocation coefficient and the preset second allocation coefficient, the initial mechanical power relationship equation is converted to obtain a target mechanical power relationship equation.

[0079] Specifically, the comprehensive coefficient K is determined by combining the preset first allocation coefficient k1 and the preset second allocation coefficient k2, as shown in the following relational expression (7):

[0080] K=k1×k2 (7)

[0081] Furthermore, the comprehensive coefficient K characterizes the variation characteristics of the speed variation rate in a wide range.

[0082] Furthermore, the initial mechanical power relationship shown in the above relationship (5) is transformed by combining the obtained comprehensive coefficient K to obtain the target mechanical power relationship, as shown in the following relationship (8):

[0083]

[0084] Step S205: Based on the rotor motion data set, multiple oscillation energy values ​​of the speed control systems in multiple hydropower units are obtained through calculations of the target mechanical power relationship and the oscillation energy relationship of the speed control controller. Figure 1 Step S102 of the illustrated embodiment will not be described in detail here.

[0085] Step S206: sort the multiple hydropower units using the multiple oscillation energy values ​​and determine the target hydropower unit that has ultra-low frequency oscillation. Figure 1 Step S103 of the illustrated embodiment will not be described in detail here.

[0086] Step S207: Use the energy storage system to suppress ultra-low frequency oscillation of the target hydropower unit to obtain an ultra-low frequency oscillation suppression result. Figure 1 Step S104 of the illustrated embodiment will not be described in detail here.

[0087] The method for suppressing ultra-low frequency oscillation of a hydropower unit provided in this embodiment, by considering the speed change rate and introducing a distribution coefficient to transform the initial mechanical power relationship, can make the target mechanical power relationship adapt to a wide range of speed change rates, so that the mechanical power can be effectively fitted under different working conditions, and thus the mechanical power of the hydropower unit can be more accurately characterized. Furthermore, in combination with the oscillation energy relationship of the speed controller, the oscillation energy of the speed regulation system can be more accurately calculated. Finally, by sorting multiple hydropower units according to multiple oscillation energy values, it is possible to quickly determine which hydropower units have ultra-low frequency oscillation problems, providing a clear target for targeted suppression measures. Finally, using energy storage to suppress ultra-low frequency oscillations of hydropower units can effectively solve the coordination problem of the primary frequency regulation performance of the hydropower unit and the ultra-low frequency oscillation suppression, and provide a new technical means for solving the ultra-low frequency oscillation problem.

[0088] In this embodiment, a method for suppressing ultra-low frequency oscillation of a hydropower unit is provided, which can be used in electronic devices such as computers, mobile phones, tablet computers, etc. Figure 3 is a flow chart of a method for suppressing ultra-low frequency oscillation of a hydropower unit according to an embodiment of the present invention. Figure 3 As shown, the process includes the following steps:

[0089] Step S301, obtain rotor motion data sets of multiple hydropower units. Figure 1 Step S101 of the illustrated embodiment will not be described in detail here.

[0090] Step S302: Based on the rotor motion data set, multiple oscillation energy values ​​of the speed control systems in multiple hydropower units are obtained by calculating the target mechanical power relationship and the oscillation energy relationship of the speed control controller. Figure 1 Step S102 of the illustrated embodiment will not be described in detail here.

[0091] Step S303: sort multiple hydropower units using multiple oscillation energy values ​​and determine the target hydropower unit that has ultra-low frequency oscillation. Figure 1 Step S103 of the illustrated embodiment will not be described in detail here.

[0092] Step S304: utilizing the energy storage system to suppress ultra-low frequency oscillation of the target hydropower unit to obtain an ultra-low frequency oscillation suppression result.

[0093] Specifically, the above step S304 includes:

[0094] Step S3041, obtaining the objective function and the initial active output of the energy storage system.

[0095] In some optional implementations, the above step S3041 includes:

[0096] Step b1, obtaining the frequency deviation of the target hydropower unit and the energy storage data set of the energy storage system.

[0097] Among them, the energy storage data set may include the storage capacity of the energy storage device, the charging and discharging efficiency of the energy storage device, the energy storage charging and discharging power, etc.

[0098] Step b2: determining the initial active output and the upper limit of the active output of the energy storage system based on the frequency deviation.

[0099] Step b3, calculating the energy storage capacity requirement of the energy storage system based on the energy storage data set.

[0100] Step b4, determining the objective function based on the energy storage capacity requirement and the upper limit of active output.

[0101] Specifically, when the unit experiences ultra-low frequency oscillation, the energy storage adjusts its active output according to the frequency deviation change of the unit, such as Figure 4 As shown in Figure 1, when the frequency deviation is within the dead zone, the active power command of the energy storage system is zero; when the frequency deviation exceeds the positive dead zone, the energy storage absorbs power; when the frequency deviation exceeds the negative dead zone, the energy storage releases power. The active power output expression of the energy storage is shown in the following relationship (9):

[0102]

[0103] Where: P represents the energy storage active power instruction; -Δf d and Δf d Indicates the upper and lower limits of the control dead zone of energy storage to suppress ultra-low frequency oscillation; K indicates the droop coefficient of energy storage to suppress ultra-low frequency oscillation; -P max and P max Indicates the upper and lower limits of the active output of energy storage.

[0104] Furthermore, the energy storage capacity is expressed as follows:

[0105]

[0106] Where: E e,t+1 represents the storage capacity of the energy storage device at time t+1; E e,t represents the storage capacity of the energy storage device at time t; ε represents the self-loss coefficient; η ch Represents the charging efficiency of energy storage equipment; η dis Indicates the discharge efficiency of energy storage equipment; Indicates the energy storage charging power; Indicates the energy storage discharge power.

[0107] Furthermore, the energy storage capacity requirement can be obtained as shown in the following equation (11):

[0108]

[0109] Where: E eu Represents the energy storage capacity requirement; S eu,max Indicates the upper limit of energy storage state; S eu,min Indicates the lower limit of energy storage state.

[0110] Furthermore, when energy storage participates in the ultra-low frequency oscillation suppression of hydropower units, the economic efficiency of energy storage technology must be considered. Therefore, the control strategy for energy storage oscillation suppression needs to be optimized to meet the energy storage active output limit and the minimum energy storage capacity. That is, the objective function is shown in the following relation (12):

[0111] minP max +E eu (12)

[0112] Step S3042, based on the objective function and the energy storage power constraint condition set, the initial active output is optimized using a particle swarm algorithm to obtain a target active output.

[0113] Among them, Particle Swarm Optimization (PSO) is an optimization algorithm based on swarm intelligence. It searches for the optimal solution in the solution space by simulating the foraging behavior of bird flocks.

[0114] The energy storage power constraint set includes the energy storage maximum charging power constraint and the energy storage maximum discharging power constraint, which are shown in the following equations (13) and (14) respectively:

[0115]

[0116] Where: Indicates the maximum limit of energy storage charging power; Indicates the maximum limit of energy storage discharge power.

[0117] Specifically, the energy storage active output limit and the minimum energy storage capacity shown in the above relationship (12) are taken as optimization targets. Under the constraints of the energy storage power constraint condition set shown in the above relationship (13) and (14), the particle swarm algorithm is used to optimize the initial active output shown in the above relationship (9) until the energy storage output that satisfies the suppression effect is obtained, then the optimization is stopped and the corresponding target active output is obtained.

[0118] Step S3043: Based on the target active output, the energy storage system is used to suppress the ultra-low frequency oscillation of the target hydropower unit to obtain an ultra-low frequency oscillation suppression result.

[0119] Specifically, based on the target active output, the energy storage system can intervene in the operating state of the hydropower unit by adjusting its output power. When the hydropower unit has ultra-low frequency oscillation, the energy storage system can quickly respond and output the corresponding active power according to the target active output requirements to offset the oscillation energy of the hydropower unit.

[0120] Exemplarily, the energy storage system can achieve ultra-low frequency oscillation suppression in the following ways:

[0121] (1) Power regulation: According to the target active output indication, the energy storage system can quickly adjust its output power and inject or absorb active power into the hydropower unit to change the power balance state of the hydropower unit, thereby suppressing ultra-low frequency oscillations.

[0122] (2) Energy storage and release: The energy storage system can store energy when the hydropower unit has excess output power and release energy when the hydropower unit has insufficient output power, so as to maintain the power balance of the system and reduce the occurrence of ultra-low frequency oscillations.

[0123] (3) Dynamic response: The energy storage system has a fast dynamic response capability and can respond quickly at the moment when ultra-low frequency oscillation occurs, providing timely active power support and effectively suppressing the development of oscillation.

[0124] The method for suppressing ultra-low frequency oscillations of a hydropower unit provided in this embodiment can directly reflect the difference between the current operating state and the standard state of the hydropower unit by obtaining the frequency deviation of the target hydropower unit, and then determine the active output of the energy storage system through the frequency deviation, so that the energy storage system can respond quickly to changes in the hydropower unit. Furthermore, the objective function is determined in combination with the energy storage capacity demand and the upper limit of the active output, so that the objective function can comprehensively consider the performance of the energy storage system and the needs of the hydropower unit. Furthermore, under the control of the objective function and the constraints of the energy storage power constraint condition set, the active output of the energy storage system can be optimized through the particle swarm algorithm, and then the target energy storage output that meets the suppression effect can be obtained through optimization. Finally, the energy storage system can effectively suppress the ultra-low frequency oscillations generated by the target hydropower unit according to the target active output, which effectively solves the coordination problem of the primary frequency regulation performance of the hydropower unit and the ultra-low frequency oscillation suppression.

[0125] In this embodiment, a device for suppressing ultra-low frequency oscillation of a hydropower unit is also provided, which is used to implement the above-mentioned embodiments and preferred implementation modes, and will not be repeated hereafter. As used below, the term "module" can be a combination of software and / or hardware that implements a predetermined function. Although the device described in the following embodiments is preferably implemented in software, the implementation of hardware, or a combination of software and hardware, is also possible and conceivable.

[0126] This embodiment provides a device for suppressing ultra-low frequency oscillation of a hydropower unit. Figure 5 As shown, the device comprises:

[0127] The first acquisition module 501 is used to acquire rotor motion data sets of multiple hydropower units.

[0128] The calculation module 502 is used to obtain multiple oscillation energy values ​​of the speed control system in multiple hydropower units based on the rotor motion data set through calculation of the target mechanical power relationship and the oscillation energy relationship of the speed controller. The target mechanical power relationship is used to fit the mechanical power with a wide range of speed change rates.

[0129] The processing module 503 is used to sort the multiple hydropower generating units by using the multiple oscillation energy values ​​and determine the target hydropower generating unit that has ultra-low frequency oscillation.

[0130] The suppression module 504 is used to suppress the ultra-low frequency oscillation of the target hydropower unit by using the energy storage system to obtain the ultra-low frequency oscillation suppression result.

[0131] In some optional embodiments, the device further comprises:

[0132] The second acquisition module is used to obtain the initial mechanical power relationship and speed change rate of the hydropower unit.

[0133] The determination module is used to determine a preset first distribution coefficient and a preset second distribution coefficient by using a rotation speed change rate.

[0134] The conversion module is used to convert the initial mechanical power relationship equation based on the preset first allocation coefficient and the preset second allocation coefficient to obtain the target mechanical power relationship equation.

[0135] In some optional implementations, the second acquisition module includes:

[0136] The first acquisition submodule is used to obtain the motion equation of the rotor of the hydropower unit.

[0137] The second acquisition submodule is used to obtain the electromagnetic power relationship and electromagnetic torque relationship of the hydropower unit.

[0138] The input submodule is used to input the electromagnetic power relation and the electromagnetic torque relation into the rotor motion equation of the hydropower unit to obtain the initial mechanical power relation of the hydropower unit.

[0139] In some optional embodiments, the suppression module 504 includes:

[0140] The third acquisition submodule is used to obtain the objective function and the initial active output of the energy storage system.

[0141] The optimization submodule is used to optimize the initial active output based on the objective function and the energy storage power constraint condition set using the particle swarm algorithm to obtain the target active output.

[0142] The suppression submodule is used to suppress the ultra-low frequency oscillation of the target hydropower unit based on the target active output by using the energy storage system to obtain the ultra-low frequency oscillation suppression result.

[0143] In some optional implementations, the third acquisition submodule includes:

[0144] The acquisition unit is used to acquire the frequency deviation of the target hydropower unit and the energy storage data set of the energy storage system.

[0145] The first determining unit is used to determine the initial active output and the upper limit value of the active output of the energy storage system based on the frequency deviation.

[0146] The calculation unit is used to calculate the energy storage capacity requirement of the energy storage system based on the energy storage data set.

[0147] The second determination unit is used to determine the objective function based on the energy storage capacity requirement and the active output upper limit value.

[0148] In some optional implementations, the energy storage power constraint condition set in the acquisition unit includes an energy storage maximum charging power constraint condition and an energy storage maximum discharging power constraint condition.

[0149] The further functional description of each of the above modules and units is the same as that of the above corresponding embodiments and will not be repeated here.

[0150] The ultra-low frequency oscillation suppression device of the hydropower unit in this embodiment is presented in the form of a functional unit, where the unit refers to an ASIC (Application Specific Integrated Circuit) circuit, a processor and memory that executes one or more software or fixed programs, and / or other devices that can provide the above functions.

[0151] The embodiment of the present invention also provides a computer device having the above Figure 5 The ultra-low frequency oscillation suppression device of the hydropower unit shown.

[0152] See also Figure 6 , Figure 6 is a schematic diagram of the structure of a computer device provided by an optional embodiment of the present invention, such as Figure 6As shown, the computer device includes: one or more processors 10, a memory 20, and interfaces for connecting various components, including high-speed interfaces and low-speed interfaces. Various components are connected to each other using different buses for communication, and can be installed on a common mainboard or installed in other ways as needed. The processor can process instructions executed in the computer device, including instructions stored in or on the memory to display the graphical information of the GUI on an external input / output device (such as a display device coupled to the interface). In some optional embodiments, if necessary, multiple processors and / or multiple buses can be used together with multiple memories. Similarly, multiple computer devices can be connected, and each device provides some necessary operations (for example, as a server array, a group of blade servers, or a multi-processor system). Figure 6 A processor 10 is taken as an example.

[0153] The processor 10 may be a central processing unit, a network processor or a combination thereof. The processor 10 may further include a hardware chip. The hardware chip may be a dedicated integrated circuit, a programmable logic device or a combination thereof. The programmable logic device may be a complex programmable logic device, a field programmable gate array, a general purpose array logic or any combination thereof.

[0154] The memory 20 stores instructions executable by at least one processor 10, so that at least one processor 10 executes the method shown in the above embodiment.

[0155] The memory 20 may include a program storage area and a data storage area, wherein the program storage area may store an operating system, an application required for at least one function; the data storage area may store data created according to the use of the computer device, etc. In addition, the memory 20 may include a high-speed random access memory, and may also include a non-transient memory, such as at least one disk storage device, a flash memory device, or other non-transient solid-state storage device. In some optional embodiments, the memory 20 may optionally include a memory remotely arranged relative to the processor 10, and these remote memories may be connected to the computer device via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0156] The memory 20 may include a volatile memory, such as a random access memory; the memory may also include a non-volatile memory, such as a flash memory, a hard disk or a solid state drive; the memory 20 may also include a combination of the above types of memory.

[0157] The computer device further comprises a communication interface 30 for the computer device to communicate with other devices or a communication network.

[0158] The embodiment of the present invention also provides a computer-readable storage medium. The method according to the embodiment of the present invention can be implemented in hardware, firmware, or can be implemented as a computer code that can be recorded in a storage medium, or can be implemented as a computer code that is originally stored in a remote storage medium or a non-temporary machine-readable storage medium and will be stored in a local storage medium through a network download, so that the method described herein can be stored in such software processing on a storage medium using a general-purpose computer, a dedicated processor, or programmable or dedicated hardware. Among them, the storage medium can be a magnetic disk, an optical disk, a read-only storage memory, a random access memory, a flash memory, a hard disk or a solid-state hard disk, etc.; further, the storage medium can also include a combination of the above types of memories. It can be understood that a computer, a processor, a microprocessor controller, or programmable hardware includes a storage component that can store or receive software or computer code. When the software or computer code is accessed and executed by a computer, a processor, or hardware, the method shown in the above embodiment is implemented.

[0159] A part of the present invention may be applied as a computer program product, such as a computer program instruction, which, when executed by a computer, can call or provide the method and / or technical solution according to the present invention through the operation of the computer. Those skilled in the art should understand that the existence of the computer program instruction in a computer-readable medium includes, but is not limited to, a source file, an executable file, an installation package file, etc., and accordingly, the way in which the computer program instruction is executed by the computer includes, but is not limited to: the computer directly executes the instruction, or the computer compiles the instruction and then executes the corresponding compiled program, or the computer reads and executes the instruction, or the computer reads and installs the instruction and then executes the corresponding installed program. Here, the computer-readable medium may be any available computer-readable storage medium or communication medium accessible to the computer.

[0160] Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations are all within the scope defined by the appended claims.

Claims

1. A method for suppressing ultra-low frequency oscillation of a hydropower unit, characterized in that: The method comprises: Obtain rotor motion datasets for multiple hydroelectric units; Based on the rotor motion data set, multiple oscillation energy values ​​of the speed control systems in multiple hydropower units are obtained through calculation of a target mechanical power relationship and an oscillation energy relationship of a speed control controller, wherein the target mechanical power relationship is used to fit the mechanical power with a wide range of speed change rates; Using the multiple oscillation energy values, the multiple hydropower generating units are sorted and a target hydropower generating unit that has ultra-low frequency oscillation is determined; The energy storage system is used to suppress the ultra-low frequency oscillation of the target hydropower unit to obtain an ultra-low frequency oscillation suppression result.

2. The method according to claim 1, characterized in that The method further comprises: Obtain the initial mechanical power relationship and speed change rate of the hydropower unit; Determining a preset first distribution coefficient and a preset second distribution coefficient using the rotation speed change rate; Based on the preset first allocation coefficient and the preset second allocation coefficient, the initial mechanical power relationship equation is converted to obtain the target mechanical power relationship equation.

3. The method according to claim 2, characterized in that Obtain the initial mechanical power relationship of the hydropower unit, including: Obtain the motion equation of the hydropower unit rotor; Obtain the electromagnetic power relationship and electromagnetic torque relationship of the hydropower unit; The electromagnetic power relationship and the electromagnetic torque relationship are input into the rotor motion equation of the hydroelectric generator set to obtain the initial mechanical power relationship of the hydroelectric generator set.

4. The method according to claim 1, characterized in that: The target hydropower unit is subjected to ultra-low frequency oscillation suppression by using an energy storage system to obtain an ultra-low frequency oscillation suppression result, including: Obtaining an objective function and an initial active output of the energy storage system; Based on the objective function and the energy storage power constraint condition set, the initial active output is optimized using a particle swarm algorithm to obtain a target active output; Based on the target active output, the energy storage system is used to suppress the ultra-low frequency oscillation of the target hydropower unit to obtain the ultra-low frequency oscillation suppression result.

5. The method according to claim 4, characterized in that Obtaining the objective function and the initial active output of the energy storage system, including: Acquire the frequency deviation of the target hydropower unit and the energy storage data set of the energy storage system; Based on the frequency deviation, determining the initial active output and the upper limit of active output of the energy storage system; Calculating the energy storage capacity requirement of the energy storage system based on the energy storage data set; The objective function is determined based on the energy storage capacity requirement and the active output upper limit.

6. The method according to claim 4, characterized in that The energy storage power constraint condition set includes an energy storage maximum charging power constraint condition and an energy storage maximum discharging power constraint condition.

7. A device for suppressing ultra-low frequency oscillation of a hydropower unit, characterized in that: The device comprises: A first acquisition module is used to acquire rotor motion data sets of multiple hydropower units; A calculation module, for obtaining multiple oscillation energy values ​​of the speed control systems in multiple hydropower units based on the rotor motion data set through a target mechanical power relationship and an oscillation energy relationship of a speed control controller, wherein the target mechanical power relationship is used to fit the mechanical power with a wide range of speed change rates; A processing module, configured to sort the plurality of hydropower generating units by using the plurality of oscillation energy values ​​and determine a target hydropower generating unit that has ultra-low frequency oscillation; The suppression module is used to use the energy storage system to suppress the ultra-low frequency oscillation of the target hydropower unit to obtain the ultra-low frequency oscillation suppression result.

8. A computer device, characterized in that: include: A memory and a processor, wherein the memory and the processor are communicatively connected to each other, the memory stores computer instructions, and the processor executes the method for suppressing ultra-low frequency oscillation of a hydropower unit according to any one of claims 1 to 6 by executing the computer instructions.

9. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a computer to execute the method for suppressing ultra-low frequency oscillation of a hydropower unit according to any one of claims 1 to 6.

10. A computer program product, characterized in that The method comprises computer instructions, wherein the computer instructions are used to enable a computer to execute the method for suppressing ultra-low frequency oscillation of a hydropower unit according to any one of claims 1 to 6.

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