A method, device and system for controlling adjustable power generation of multiple power generation systems

Abstract

The present invention discloses an adjustable power generation control method, device and system for multiple power generation systems. The adjustable power generation control device includes a data acquisition unit, a calculation and judgment unit and a control output unit. The adjustable power generation control system includes a power generation control module, multiple power generation systems and a water condition monitoring system. By determining the second number of power generation systems that are most suitable for the current dam to be turned on according to the water flow data group of the dam, and performing corresponding control and adjustment on the number of power generation systems according to the second number and the first number of power generation systems currently turned on, the adjustable power generation control method, device and system realize the controllability of power generation output under different water flow conditions, and improve the comprehensive power generation efficiency of the hydropower station with multiple power generation systems.

Description

Technical Field

[0001] The present invention relates to the field of adjustable power generation control of multiple power generation systems, and relates to an adjustable power generation control method, device and system for multiple power generation systems. Background Art

[0002] Due to the influence of precipitation and seasonal changes in the area where the hydropower station is located, the water head at the input end of the hydropower station changes significantly, so the water inlet flow may deviate from the expected working point of the hydropower station for a long time. However, the turbine must always maintain the rated speed. Therefore, the mismatch between the turbine speed and the flow at this time not only affects the conversion efficiency of the unit, wastes hydropower resources, and seriously reduces the output power of the hydropower station, but also aggravates the cavitation effect of the turbine, further increases the noise and vibration of the unit, and reduces the service life of the turbine and the excitation power generation system.

[0003] In the prior art, a single water pipe is used to connect the upstream dam to the downstream hydropower station, and then to a single turbine or two turbines. Each turbine is connected to an AC excitation synchronous power generation system, and is directly connected to the power grid after power generation. Among them, an AC excitation synchronous power generation system (excitation power generation system for short) is used for power generation. To meet the requirements of the power grid frequency, the turbine and the excitation power generation system need to maintain constant speed operation. However, due to the constraints of the turbine energy conversion characteristics, the turbine efficiency is coupled with the operating speed and the water inlet flow rate. When the flow rate changes, the optimal efficiency operating speed of the turbine also changes accordingly.

[0004] However, the prior art still has the following defects: due to the different water flow conditions in different time periods of the year, it is very difficult to synchronize the frequency and voltage of a dam with multiple power generation systems with fixed configurations, making it difficult to implement the parallel connection technology for multiple power generation systems or the effect is poor, resulting in a mismatch between the turbine speed and the flow rate. In addition to affecting the conversion efficiency of the unit, wasting hydropower resources, and seriously reducing the output power of the hydropower station, it also aggravates the cavitation effect of the turbine, further increases the noise and vibration of the unit, and reduces the service life of the turbine and the excitation power generation system.

[0005] Therefore, there is a need for an adjustable power generation control method, device and system for a multiple power generation system, so as to overcome the above-mentioned defects in the prior art. Summary of the invention

[0006] In view of the above existing technical problems, the object of the present invention is to provide an adjustable power generation control method, device and system for a multiple power generation system, so as to improve the comprehensive power generation efficiency of the hydropower station of the multiple power generation system.

[0007] The present invention provides an adjustable power generation control method for multiple power generation systems, the adjustable power generation control method comprising: monitoring and acquiring a water flow data group of a dam and a first number of power generation systems currently turned on; the water flow data group comprises a water level, a water velocity and a water flow direction; the power generation system comprises a permanent magnet generator and an electric energy conversion unit, the electric energy conversion unit being used to uniformly convert different AC voltages generated by the permanent magnet generator into a preset AC voltage; judging a second number of first power generation systems that need to be kept turned on among multiple power generation systems according to the water level, the water velocity, the water flow direction and a preset control method; and turning on or off a corresponding number of power generation systems in turn according to the first number and the second number, thereby controlling the power generation output.

[0008] In one embodiment, judging the second number of first power generation systems that need to be kept turned on among multiple power generation systems based on the water level, the water velocity, the water flow direction and a preset control method specifically includes: when the water level is higher than the safe water level threshold, calculating the second number of first power generation systems that need to be kept turned on based on the water velocity, the water flow direction and the unit water inlet flow threshold of each power generation system.

[0009] In one embodiment, the corresponding number of power generation systems are turned on or off in sequence according to the first number and the second number, so as to control the power generation output, which specifically includes: judging the size relationship between the first number and the second number, and calculating the difference between the first number and the second number; if the first number is greater than the second number, turning off the power generation systems corresponding to the difference in sequence from top to bottom; if the first number is less than the second number, turning on the power generation systems corresponding to the difference in sequence from bottom to top.

[0010] In one embodiment, the adjustable power generation control method further includes: sending the water flow data group, the first quantity and the second quantity to a user.

[0011] The present invention also provides an adjustable power generation control device for multiple power generation systems, the adjustable power generation control device comprising a data acquisition unit, a calculation and judgment unit, and a control output unit, wherein the data acquisition unit is used to monitor and obtain a water flow data group of a dam and a first number of power generation systems currently turned on; the water flow data group comprises a water level, a water velocity, and a water flow direction; the power generation system comprises a permanent magnet generator and an electric energy conversion unit, the electric energy conversion unit being used to uniformly convert different AC voltages generated by the permanent magnet generator into a preset AC voltage; the calculation and judgment unit is used to judge a second number of first power generation systems that need to be kept turned on among multiple power generation systems according to the water level, the water velocity, the water flow direction, and a preset control method; the control output unit is used to turn on or off a corresponding number of power generation systems in sequence according to the first number and the second number, thereby controlling the power generation output.

[0012] In one embodiment, the adjustable power generation control device further includes an information sending unit, and the information sending unit is used to send the water flow data group, the first quantity and the second quantity to a user.

[0013] In one embodiment, the calculation and judgment unit is also used to: when the water level is higher than the safety water level threshold, calculate the second number of the first power generation systems that need to be kept open based on the water speed, the water flow direction and the unit water inlet flow threshold of each power generation system.

[0014] In one embodiment, the control output unit is also used to: determine the size relationship between the first quantity and the second quantity, and calculate the difference between the first quantity and the second quantity; if the first quantity is greater than the second quantity, then shut down the power generation systems corresponding to the difference from top to bottom; if the first quantity is less than the second quantity, then start up the power generation systems corresponding to the difference from bottom to top.

[0015] The present invention also provides an adjustable power generation control system for multiple power generation systems, the adjustable power generation control system comprising a power generation control module, multiple power generation systems and a water condition monitoring system, the power generation system comprising a permanent magnet generator and an electric energy conversion unit, the water condition monitoring system is communicatively connected to the power generation control module, the power generation control module is respectively connected to each power generation system, wherein the electric energy conversion unit is used to uniformly convert different AC voltages generated by the permanent magnet generator into a preset AC voltage; the power generation control module is used to execute the adjustable power generation control method for multiple power generation systems as described above according to the water flow data group monitored by the water condition monitoring system.

[0016] Compared with the prior art, the embodiments of the present invention have the following beneficial effects:

[0017] The present invention provides an adjustable power generation control method, device and system for multiple power generation systems. The method determines the second number of power generation systems that are most suitable for opening the current dam according to the water flow data group of the dam, and controls and adjusts the number of power generation systems accordingly according to the second number and the first number of power generation systems that are currently opened. The adjustable power generation control method, device and system realize the controllability of power generation output under different water flow conditions, and improves the comprehensive power generation efficiency of the hydropower station with multiple power generation systems.

[0018] Furthermore, the adjustable power generation control method, device and system of a multi-power generation system provided by the present invention also uniformly converts the different AC voltages generated by the permanent magnet generator into a preset AC voltage through the power conversion unit of the power generation system, thereby improving the adaptability of the turbine and flow, and further improving the service life of the power generation system. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The present invention will be further described below in conjunction with the accompanying drawings, wherein:

[0020] Figure 1 A flow chart showing an embodiment of an adjustable power generation control method for a multi-power generation system according to the present invention;

[0021] Figure 2 A structural diagram showing an embodiment of an adjustable power generation control device for a multi-power generation system according to the present invention;

[0022] Figure 3 A structural diagram of an embodiment of an adjustable power generation control system for a multi-power generation system according to the present invention is shown. DETAILED DESCRIPTION

[0023] 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. Specific embodiment 1

[0025] The embodiment of the present invention firstly describes an adjustable power generation control method for a multi-power generation system. Figure 1 A flow chart of an embodiment of an adjustable power generation control method for a multiple power generation system according to the present invention is shown.

[0026] like Figure 1 As shown, the method comprises the following steps:

[0027] S1: Monitor and obtain the water flow data set of the dam and the first number of the currently turned on power generation system.

[0028] The water flow is affected by natural weather. The difference between the water flow in the dry season and the wet season is often more than 5 times. In order to stabilize the speed of the excitation generator, the water flow must be controlled within a certain range. During the wet season, when the water flow exceeds the design flow, the turbine speed will exceed the design speed. For safety reasons, the excess water can only be abandoned to maintain the generator speed, but this will waste the water that could have been used for power generation. During the dry season, the water flow decreases, the turbine speed slows down, and the synchronous generator frequency cannot reach the grid-connected frequency. Therefore, the sluice gate can only be closed at this time to stop power generation, which will also waste the water that could have been used for power generation.

[0029] Since the annual and monthly water volume is unpredictable, traditional hydropower stations are usually designed in a more conservative way, based on the average water flow over many years. However, the actual power generation is often only 20-30% of the actual usable water energy, resulting in a waste of hydraulic energy. The existing technology is usually connected to the downstream hydropower station through a single water pipe, and then connected to the AC excited synchronous generator through one or more turbines to generate electricity, and then the generated electricity is directly connected to the power grid.

[0030] Most importantly, such a fixed configuration will first lead to its power generation work being unable to adapt to the water flow rate to achieve the best efficiency: when the water flow rate is large, the number of power generation systems is insufficient to achieve the highest efficiency power generation; when the water flow rate is too small, the power generation system will waste power consumption; secondly, such a fixed configuration will not only affect the conversion efficiency of the unit, waste hydropower resources, and seriously reduce the output power of the hydropower station, but also aggravate the cavitation effect of the turbine, further increase the noise and vibration of the unit, and reduce the service life of the turbine and excitation generator.

[0031] In this regard, the embodiment of the present invention monitors the water flow conditions and flexibly adjusts the number of power generation systems according to the water flow conditions to adapt them to the water flow in different situations, so as to achieve the highest power generation efficiency as much as possible.

[0032] The water flow data group includes water level, water velocity and water flow direction; the power generation system includes a permanent magnet generator and an electric energy conversion unit, and the electric energy conversion unit is used to uniformly convert different AC voltages generated by the permanent magnet generator into a preset AC voltage. In practical applications, in addition to the permanent magnet generator, the power generation system also includes a turbine and a valve. The permanent magnet generator needs to be connected to the turbine for use. When generating electricity through hydropower, the corresponding valve is controlled to open so that the water flows through the turbine, so that the turbine drives the permanent magnet generator to generate electricity.

[0033] S2: According to the water level, the water speed, the water flow direction and the preset control method, determine the second number of the first power generation systems that need to be kept turned on among the multiple power generation systems.

[0034] After obtaining the water flow data set, in order to flexibly adapt the power generation efficiency to the water flow data set by adjusting the number of power generation systems, the number of power generation systems adapted to the water flow must first be calculated based on the water flow data set, and then adjusted based on the number.

[0035] In one embodiment, this step includes: when the water level is higher than the safety water level threshold, calculating the second number of first power generation systems that need to remain turned on based on the water velocity, the water flow direction and the unit water inlet flow threshold of each power generation system.

[0036] S3: According to the first number and the second number, a corresponding number of power generation systems are turned on or off in sequence, so as to control the power generation output.

[0037] After calculating and obtaining the second number of the first power generation systems that need to be kept turned on in the multiple power generation systems, the number of the power generation systems can be adjusted according to the current turning-on status of the power generation systems. Since the configurations of the multiple power generation systems may be different, in order to synchronize the voltage output to the power grid with the power grid frequency (thereby avoiding electromagnetic oscillation or even loss of step of the generator), an embodiment of the present invention is provided with an electric energy conversion system in the power generation system to control the power generation output, and the electric energy conversion system includes a rectifier unit, an optimal power control unit and an inverter unit; wherein the rectifier unit converts the AC power generated by the permanent magnet generator into DC power (the rectifier unit also includes a main rectifier circuit and a filter circuit); the optimal power control unit detects the voltage and current output by the rectifier unit and provides it to the inverter unit to control the output of the optimal power to the power grid (the optimal power control unit also includes a DC voltage conversion circuit, a detection circuit and a control circuit; the DC voltage conversion circuit converts the variable DC voltage generated by the rectifier unit into a fixed DC voltage and outputs it to the inverter unit); the inverter unit converts the DC voltage generated by the rectifier unit into an AC voltage of a common frequency, voltage, phase sequence and waveform equivalently, and the inverter unit also includes a filter circuit and a protection circuit.

[0038] In one embodiment, this step specifically includes: determining the size relationship between the first quantity and the second quantity, and calculating the difference between the first quantity and the second quantity; if the first quantity is greater than the second quantity, shutting down the power generation systems corresponding to the difference in sequence from top to bottom; if the first quantity is less than the second quantity, shutting down the power generation systems corresponding to the difference in sequence from bottom to top.

[0039] In one embodiment, the adjustable power generation control method further includes: sending the water flow data group, the first quantity and the second quantity to a user.

[0040] An embodiment of the present invention describes an adjustable power generation control method for multiple power generation systems, by determining the second number of power generation systems that are most suitable for opening the current dam based on the water flow data group of the dam, and performing corresponding control adjustments on the number of power generation systems based on the second number and the first number of power generation systems that are currently opened. The adjustable power generation control method realizes the controllability of power generation output under different water flow conditions and improves the comprehensive power generation efficiency of the hydropower station with multiple power generation systems. Specific embodiment 2

[0042] In addition to the above method, the embodiment of the present invention also describes an adjustable power generation control device for a multi-power generation system. Figure 2 A structural diagram of an embodiment of an adjustable power generation control device for a multiple power generation system according to the present invention is shown.

[0043] like Figure 2 As shown, the adjustable power generation control device includes a data acquisition unit 11, a calculation and judgment unit 12 and a control output unit 13.

[0044] The data acquisition unit 11 is used to monitor and acquire a water flow data group of the dam and a first number of the currently turned-on power generation systems. The water flow data group includes a water level, a water velocity, and a water flow direction; the power generation system includes a permanent magnet generator and an electric energy conversion unit, and the electric energy conversion unit is used to uniformly convert different AC voltages generated by the permanent magnet generator into a preset AC voltage.

[0045] The calculation and judgment unit 12 is used to judge the second number of the first power generation systems that need to be kept turned on among the multiple power generation systems according to the water level, the water speed, the water flow direction and the preset control method. In one embodiment, the calculation and judgment unit 12 is also used to: when the water level is higher than the safe water level threshold, calculate the second number of the first power generation systems that need to be kept turned on according to the water speed, the water flow direction and the unit water inlet flow threshold of each power generation system.

[0046] The control output unit 13 is used to sequentially turn on or off a corresponding number of power generation systems according to the first number and the second number, thereby controlling the power generation output. In one embodiment, the control output unit 13 is also used to: determine the size relationship between the first number and the second number, and calculate the difference between the first number and the second number; if the first number is greater than the second number, then sequentially turn off the power generation systems corresponding to the difference from top to bottom; if the first number is less than the second number, then sequentially turn on the power generation systems corresponding to the difference from bottom to top.

[0047] In one embodiment, the adjustable power generation control device further includes an information sending unit, and the information sending unit is used to send the water flow data group, the first quantity and the second quantity to a user.

[0048] An embodiment of the present invention describes an adjustable power generation control device for multiple power generation systems. The device determines the second number of power generation systems that are most suitable for the current dam to be turned on according to the water flow data group of the dam, and controls and adjusts the number of power generation systems accordingly according to the second number and the first number of power generation systems that are currently turned on. The adjustable power generation control device achieves controllability of power generation output under different water flow conditions, thereby improving the comprehensive power generation efficiency of the hydropower station with multiple power generation systems. Furthermore, the adjustable power generation control device for multiple power generation systems described in an embodiment of the present invention also converts the different AC voltages generated by the permanent magnet generator into a preset AC voltage through the power conversion unit of the power generation system, thereby improving the adaptability of the turbine and flow, and further improving the service life of the power generation system. Specific embodiment three

[0050] In addition to the above methods and apparatus, the present invention also describes an adjustable power generation control system for a multiple power generation system. Figure 3 A structural diagram of an embodiment of an adjustable power generation control system for a multi-power generation system according to the present invention is shown.

[0051] like Figure 3 As shown, the adjustable power generation control system includes a power generation control module 1, multiple power generation systems 2 and a water condition monitoring system 3, wherein the power generation system 2 includes a permanent magnet generator and an electric energy conversion unit, and the water condition monitoring system 3 is communicatively connected to the power generation control module 1, and the power generation control module 1 is respectively connected to each power generation system 2.

[0052] Among them, the water condition monitoring system 3 is installed on the upstream dam to monitor the water flow, and the power conversion unit is used to uniformly convert the different AC voltages generated by the permanent magnet generator into a preset AC voltage; the power generation control module is used to execute the adjustable power generation control method of multiple power generation systems as described above according to the water flow data group monitored by the water condition monitoring system. In actual application, the water condition monitoring system 3 is connected to each power generation system 2 in sequence through multiple water pipes, and each power generation system 2 is arranged vertically in sequence. As the water flow increases, the power generation control module 1 controls the power generation system to be turned on in sequence from bottom to top.

[0053] In order to synchronize the voltage output to the power grid with the power grid frequency (thereby avoiding electromagnetic oscillation or even loss of step of the generator), an embodiment of the present invention provides an energy conversion system in the power generation system to control the power generation output, and the energy conversion system includes a rectifier unit, an optimal power control unit and an inverter unit; wherein the rectifier unit converts the alternating current generated by the permanent magnet generator into direct current (the rectifier unit also includes a main rectifier circuit and a filter circuit); the optimal power control unit detects the voltage and current output by the rectifier unit and provides them to the inverter unit to control the output of the optimal power (maximum power) to the power grid (the optimal power control unit also includes a DC voltage conversion circuit, a detection circuit and a control circuit; the DC voltage conversion circuit converts the variable DC voltage generated by the rectifier unit into a fixed DC voltage and outputs it to the inverter unit); the inverter unit converts the DC voltage generated by the rectifier unit into an AC voltage of a commonly used frequency, voltage, phase sequence and waveform equivalently, and the inverter unit also includes a filter circuit and a protection circuit.

[0054] An embodiment of the present invention describes an adjustable power generation control system for multiple power generation systems. By determining the second number of power generation systems that are most suitable for the current dam to be turned on based on the water flow data group of the dam, and performing corresponding control adjustments on the number of power generation systems based on the second number and the first number of power generation systems that are currently turned on, the adjustable power generation control system achieves controllability of power generation output under different water flow conditions, thereby improving the comprehensive power generation efficiency of the hydropower station with multiple power generation systems. Furthermore, the adjustable power generation control system for multiple power generation systems described in the embodiment of the present invention also converts the different AC voltages generated by the permanent magnet generator into a preset AC voltage through the power conversion unit of the power generation system, thereby improving the adaptability of the turbine and flow, and further improving the service life of the power generation system.

[0055] The specific embodiments described above further illustrate the purpose, technical solutions and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. It is particularly pointed out that for those skilled in the art, any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the scope of protection of the present invention.

Claims

1. An adjustable power generation control method for a multi-power generation system, characterized in that: The adjustable power generation control method comprises: Monitoring and acquiring a water flow data set of a dam and a first number of currently activated power generation systems; the water flow data set includes a water level, a water velocity, and a water flow direction; the power generation system includes a permanent magnet generator and an electric energy conversion unit, and the electric energy conversion unit is used to uniformly convert different AC voltages generated by the permanent magnet generator into a preset AC voltage; According to the water level, the water velocity, the water flow direction and the preset control method, the second number of power generation systems that need to be kept turned on among the multiple power generation systems is determined; wherein, when the water level is higher than the safe water level threshold, the second number of power generation systems that need to be kept turned on is calculated according to the water velocity, the water flow direction and the unit water inlet flow threshold of each power generation system; According to the first quantity and the second quantity, a corresponding number of power generation systems are turned on or off in sequence to control the power generation output, wherein the size relationship between the first quantity and the second quantity is determined, and the difference between the first quantity and the second quantity is calculated; if the first quantity is greater than the second quantity, the power generation systems corresponding to the difference are turned off in sequence from top to bottom; if the first quantity is less than the second quantity, the power generation systems corresponding to the difference are turned on in sequence from bottom to top.

2. The adjustable power generation control method of a multi-generation system according to claim 1, characterized in that: The adjustable power generation control method further comprises: The water flow data set, the first quantity, and the second quantity are sent to a user.

3. An adjustable power generation control device for a multi-power generation system, characterized in that: The adjustable power generation control device includes a data acquisition unit, a calculation and judgment unit, and a control output unit, wherein: The data acquisition unit is used to monitor and acquire a water flow data group of the dam and a first number of the currently turned-on power generation systems; the water flow data group includes a water level, a water velocity, and a water flow direction; the power generation system includes a permanent magnet generator and an electric energy conversion unit, and the electric energy conversion unit is used to uniformly convert different AC voltages generated by the permanent magnet generator into a preset AC voltage; The calculation and judgment unit is used to judge the second number of power generation systems that need to be kept turned on among the multiple power generation systems according to the water level, the water speed, the water flow direction and the preset control method; wherein the calculation and judgment unit is further used to: when the water level is higher than the safe water level threshold, calculate the second number of power generation systems that need to be kept turned on according to the water speed, the water flow direction and the unit water inlet flow threshold of each power generation system; The control output unit is used to turn on or off a corresponding number of power generation systems in sequence according to the first number and the second number, thereby controlling the power generation output, wherein the control output unit is also used to: determine the size relationship between the first number and the second number, and calculate the difference between the first number and the second number; if the first number is greater than the second number, turn off the power generation systems corresponding to the difference in sequence from top to bottom; if the first number is less than the second number, turn on the power generation systems corresponding to the difference in sequence from bottom to top.

4. The adjustable power generation control device for a multi-generation system according to claim 3, characterized in that: The adjustable power generation control device further includes an information sending unit, and the information sending unit is used to send the water flow data group, the first quantity and the second quantity to a user.

5. An adjustable power generation control system for multiple power generation systems, characterized in that: The adjustable power generation control system includes a power generation control module, multiple power generation systems and a water condition monitoring system, the power generation system includes a permanent magnet generator and an electric energy conversion unit, the water condition monitoring system is communicatively connected to the power generation control module, and the power generation control module is respectively connected to each power generation system, wherein the electric energy conversion unit is used to uniformly convert different AC voltages generated by the permanent magnet generator into a preset AC voltage; the power generation control module is used to execute the adjustable power generation control method of multiple power generation systems as described in any one of claims 1-2 according to the water flow data group monitored by the water condition monitoring system.

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