JPS62126276A - Operation controller for pumping-up hydraulic machinery - Google Patents

Abstract

PURPOSE:To prevent the large energy loss and generation of vibration due to the countercurrent in case of high head by restricting the adjustment quantity of a prerotation generator according to the detected actual net pump head. CONSTITUTION:An axial input detector 7 for detecting the axial input P of a pumping-up hydraulic machine 1 is installed, and a calculator 8 which outputs the operation quantity X from the axial input P and a set axial input Po is installed. The operation quantity X controls a prerotation generator 6 through a controller 9. A net pump head detector 14 for detecting the actual net pump head is installed, and the limit operation quantity Xlimit is outputted from a restricting device 15 according to the detection value. When the operation quantity X is below or over the limit operation quantity Xlimit, the controller 9 restricts the adjustment quantity of the prerotation generator 6 according to the limit operation quantity Xlimit and allows the axial input P to accord with a demanded axial input Po.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an operation control device for a pumping hydraulic machine such as a pump or a pump-turbine, and particularly to a pre-swirl generating device provided in a suction side pipe of a pumping hydraulic machine. The present invention relates to an operation control device that adjusts and controls the operation of a pumping water horn machine.

[Technical background and problems of the invention]

Conventionally, in pumped storage power generation plants, during power generation operation, the opening degree of the guide vanes is adjusted to change the flow rate according to the demands of the power system, and the output of the generator motor can be varied within a range of about 100% to 50%. It is being done. Furthermore, recently, it has been proposed to adjust the shaft input and pumping amount of a pump or a pump-turbine even during pumping operation for flexible operation of power systems.

FIG. 3 shows a conventional operation control device that adjusts shaft input during pumping operation. During pumping operation, pump turbine 1 is driven by generator motor 2 to pump water from lower pond 3 to upper pond 4. During this pumping operation, a pre-swirl generator 6 is installed in the suction pipe 5 of the pump-turbine 1 on the suction side. This pre-swirl generating device 6 imparts swirl in a predetermined direction to the water flow flowing into the pump-turbine 1 in advance. The shaft input detector 7 detects the shaft input P of the generator motor 2, and the calculator 8 presets the adjustment amount of the pre-swing generator 6, that is, the operation ff1X, as the actual shaft input P from the shaft input detector 7. requested axis input P. Based on which difference is obtained, an operation set signal x representing this operation amount is generated.

The controller 9 determines that the actual axis input P is the requested axis input P based on the operation amount signal X from the calculator 8. The pre-turn generating device 6 is controlled to match the pre-turn strength.

Various types of pre-swirl generators 6 have been proposed. For example, the pre-swirl generator shown in FIG. Based on the output of 9, the strength of the pre-turn is controlled by rotating these movable fins 10 as indicated by the arrows. Further, the pre-swirl generating device 6 shown in FIG. 5 has a plurality of nozzles 11 installed in the pump-turbine suction pipe 5, and jets high-pressure water sent through a high-pressure water pipe 12 from the nozzles 11 to generate pre-swirl. Give. The controller 9 controls the strength of the pre-swirling by adjusting the opening degree of a flow rate regulating valve 13 provided in the high-pressure water pipe 12. By controlling such pre-swing, the shaft input and the amount of water pumped are adjusted.

Changes in shaft input and water pumping amount due to pre-turning will be explained in Fig. 6. In Fig. 6, the horizontal axis shows the pumped water ff1Q, and the vertical axis shows the total head H and the shaft input P. The curves a1 and bl are the relationship between the pumped water flt Q and the total head day when no pre-turn is given, respectively. and curves a and b2 show the relationship between Q and H when a pre-swing is given in the same direction as the rotation direction of the pump impeller, and the relationship between Q and P of 1y. The relationship between each is shown.

As can be seen from these curves a, bl, a, and b2, for example, when operating to obtain a total head of 1 when there is no pre-turn, the pumping water and shaft input are Q and P, respectively.
, but when a pre-turn is applied, the pumping water 91 and the shaft input change to Q and P, respectively, under the operating condition of 11 and 1, which is the same total head as described above, H. This 12
The degree of change in the pumping amount Q and shaft input P such as fJ2 depends on the strength of the pre-turn, so by adjusting the pre-turn generator and changing the strength of the pre-turn, the shaft input and pumping amount can be changed. can be controlled.

However, although there is no problem with the conventional pre-swing generating device when the head is low, serious problems may occur when the head becomes large. In other words, when the height drop is -1h, when there is no pre-swivel, the pumping amount is Q and the import force is P, but if the pre-swivel is given at a height of 7Hh and the pump characteristics are set to curves a and b, the operation will be At the point, the total head is Hh and the amount of water pumped is Qh2. This pumped water amount Q h 2 is negative,
Water will flow back from the upper pond to the lower pond. This results in a large loss of pumping energy and also generates large vibrations in the pump itself.

The pump characteristic curves a and b will diverge from curves a and b1 as the pre-swivel is made stronger, so even if the head is not that large, if the pre-swivel is made excessive, the same problem as mentioned above will occur. Become.

[Purpose of the invention]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an operation control device for a hydraulic machine that prevents large energy loss from occurring during high head and prevents excessive vibration from occurring in a pump or a pump-turbine.

[Summary of the invention]

In order to achieve this objective, the present invention provides an operation control lm that controls the operating state of pumping hydraulic machines such as pumps and pump-turbines.
The device includes a pre-swirl generator provided in the suction side pipe of the pumping hydraulic machine, a control means for adjusting the pre-swirl generator to control the degree of pre-swirl, and a control means for controlling the extent of the pre-swirling, The present invention is characterized by comprising a lift height detection means for detecting the lift height, and a limiting means for limiting the adjustment m of the pre-swing generator according to the output of the total lift degree detection means.

[Embodiments of the invention]

An embodiment of the operation control device for hydraulic machinery according to the present invention will be described below with reference to FIGS. 1 and 2, in which the same parts as in FIGS. 3 to 6 are denoted by the same reference numerals. do.

In FIG. 1, a pump turbine 1 is driven by a generator motor 2 during pumping operation to pump water from a lower pond 3 to an upper pond 4. A pre-swirl generator 6 is installed in the suction side conduit 5 of the pump-turbine 1. Of course, this suction side pipe line 5 acts as a suction pipe during power generation operation. This pre-swirl generator 6 causes the water flow flowing into the pump-turbine 1 to swirl in a predetermined direction (-JL).The shaft input detector 7 detects the shaft input P of the generator motor 2, and is the adjustment h1 of the pre-turn generator 6, that is, the operation H7X, which is obtained from the difference between the actual axis input P from the first input detector 7 and the preset required axis input P, and the operation representing this operation amount. h1 signal X is generated.

The total head detector 14 calculates the required total head H' of the pump from the water level difference between the lower reservoir 3 and the upper reservoir 4, and outputs it to the restriction device 15. This limiting device 15 generates a limit operation amount signal representing a limit value XLim1t of the operation amount of the pre-turn generator 6 based on the total lift i-1' detected by the total lift detector 14. The controller 1-0-ra 9 receives the operation amount signal X from the calculator 8 and the limit operation m signal X from the limiter 15.
Compare the operation amount signal X to the limit operation a signal X Lim
1 t or less, the pre-turn generator 6 is adjusted according to the operation signal X, and the operation amount signal X is the limit value signal X Li
When m1t is exceeded, the pre-turn generator 6 is adjusted in accordance with the limit operation m signal X Lim1t.

Limit operation m signal X Lim1t generated by the limiting device 15
is defined as follows. That is, in Figure 6,
First, the allowable operating range of the pump 1 is determined according to the pump characteristics and usage conditions. In this example, this allowable operating range is
For example, it is determined to be on the right side of the dotted line ρ. Next, this dotted line ρ and curve a1. Find the intersection with a. curve a
, a represent the pump characteristics when the operation (2) is X and x2, respectively, so from this intersection point, the maximum total head of the pump for the operation ff1X1°×2 is calculated as l-1maX1.

HIIlaX2 is required. Although FIG. 6 shows only the characteristic curves related to the operations Xl and The maximum total head HmaX for a large number of manipulated variables x is determined by The operation ff1X and the maximum total head Hm obtained in this way
The relationship with ax is graphed as shown in FIG.

From the graph of FIG. 2, it is possible to determine the limit operation amount X'Lim for the pump maximum total head 11'max during any pumping operation. Therefore, the limiting device 15 has the maximum total lift 1max and the limit operation 51 X Li in FIG.
For example, store the relationship with m1t in a table -C, and set the manually input total head 1'' from the total head detector 14 as the maximum total head H'max in the allowable operating range, and set it against this as J'max.
The limit operation amount X' Lim1t is determined from the above table and output.

Next, the operation of the device according to the present invention will be explained.

When the pump turbine 1 is in pumping operation and is pumping water from the lower reservoir 3 to the upper reservoir 4, the shaft input detector 7 detects the shaft input P at this time, and the generator 8 is preset with this shaft input P. requested axis input P. Calculate the operation Q% X from which difference. -h, the head height detector 14 detects the total head H' of the pump from the water level difference between the upper reservoir 4 and the lower reservoir 3. The limiting device 15 generates from this total head H' a limit operation amount signal representing the limit operation m X Lim1t when this total head is taken as the maximum total head H'maX.

The controller 9 compares the operation amount signal X from the calculator 8 with the limit operation signal QXLimit, etc., and adjusts the pre-turn generator 6 according to the operation amount signal The shaft input P is required and the human power P is required.

match. In this way, pump water Tr! 1 is a preset required axis input P. pumped water is operated.

On the other hand, when the operation amount X exceeds the operation limit tnXLimit, the controller 9 adjusts the pre-turn generating device 6 according to the operation limit m X Lim1t. This limit operation amount
Since Lim1t is selected so that the pump-turbine does not go into an excessive operating state, by maintaining the operation amount of the pre-swirl generator 6 at the limit operation ■, the pump-turbine is prevented from falling into an excessive operating state. .

Depending on the pump, large vibrations occur near the cut-off point, that is, near the point where the pumped water amount is zero, so in the above embodiment, the pumping amount m is zero as shown by the dotted line ρ in Fig. 6 as the permissible operating range. We selected a positive value that is quite far from . However, the present invention is not limited to this, and the cut-off head of the pump may be selected as the maximum allowable total head,
Also, 'J' due to backflow at the pump inlet 7. ,) '5
The reverse flow start head can also be selected to prevent increased vibration and cavitation.

In addition, in the above embodiment, the shaft input was adjusted to a predetermined value, but since the shaft input and pumped water change by adjusting the pre-swing generation circuit, the pumped water amount is adjusted to a preset predetermined value. It can also be adjusted.

〔Effect of the invention〕

As is clear from the above description, according to the present invention, the amount of adjustment of the pre-swing generator is limited according to the output of the total head detection means that detects the actual total head of the pumping hydraulic machine. Excessive pre-turning can be prevented, and large energy loss and large vibrations can be prevented from occurring.

[Brief explanation of drawings]

Fig. 1 shows an embodiment of the operation control device for a pumping hydraulic machine according to the present invention, and Fig. 2 is a schematic diagram showing the relationship between the maximum total lift shown in Fig. 1 and the limit operation amount of the pre-swirl generating device. Fig. 3 is a schematic diagram showing the operation control head of a conventional pumping hydraulic machine, Figs. It is a diagram showing the characteristics of the pump when it is applied and when it is not applied. 1... Pump turbine, 6... Pre-swirl generator, 8...
- Reactor, 9... Controller, 8, 9... Control means, 14... Total lift detection means, 15... Limiting device. Applicant's agent 4ji Fujio Figure 2 Figure 5 Figure 6

Claims (1)

[Scope of Claims] 1. In an operation control device for controlling the operating state of a pumping hydraulic machine such as a pump or a pump-turbine, a pre-swirl generating device provided in a suction side pipe of the pumping hydraulic machine; a control means for controlling the degree of pre-swing by adjusting the generating device; a total head detecting means for detecting the actual total head of the pumping hydraulic machine; and a control means for controlling the pre-swing generator according to the output of the total head detecting means. 1. An operation control device for a pumping hydraulic machine, comprising: limiting means for limiting the amount of adjustment. 2. The limiting means generates a limit operation amount signal based on the output of the total head detection means, and the control means generates an operation amount signal according to the difference between a preset operating condition and an actual operating condition. an arithmetic device; and when the manipulated variable signal is smaller than the limit manipulated variable signal, the pre-turn is generated based on the manipulated variable signal, and when the manipulated variable signal exceeds the limit manipulated variable signal, the pre-turn is generated based on the limit manipulated variable signal. The operation control device for a pumping hydraulic machine according to claim 1, further comprising a controller that adjusts the device. 3. The limiting means determines in advance the relationship between the manipulated variable of the preswirl generating device and the cut-off head of the pumping hydraulic machine for this manipulated variable, and determines the manipulated variable when the output of the total head detecting means is the cut-off head. 3. The operation control device for a pumping hydraulic machine according to claim 2, wherein: is determined from the above relationship and is outputted as the limit operation amount signal. 4. The limiting means determines in advance the relationship between the operation amount of the pre-swirl generating device and the backflow start head of the pumping hydraulic machine with respect to this operation amount, and determines the relationship between the operation amount of the pre-swirl generating device and the backflow start head of the pumping hydraulic machine, and the output of the total head detection means as the backflow start head. 3. The operation control device for a pumping hydraulic machine according to claim 2, wherein the operation amount is determined from the above relationship and is outputted as the limit operation amount signal.