JPS6375364A - Pump stationary operation controlling method for branching conduit pumped storage power plant - Google Patents

Abstract

PURPOSE:To operate each machine under optimum conditions, by operating a certain machine for power generation while operating another machine for pumping, in case of a branching conduit pumped storage power plant where plural units of hydraulic machines are connected to a single pipe line. CONSTITUTION:Each signal out of flowmeters 9, 10 and 11 and level detectors 12 and 13 is inputted into an arithmetic and control unit 14, and an optimum flow rate is operated. This operated result is led into guide vane controllers 15 and 16, and each opening of guide vanes 17 and 18 for a pump operation machine and a turbine operation machine is controlled. Therefore, these machines can be operated under an optimum head or a pump head commensurate to an electric power demand, undependent on upper and lower pond levels at that time.

Description

[Detailed description of the invention] [Object of the invention] (Industrial application field) The present invention relates to a branch channel pumping system in which a plurality of pump turbines, etc. are connected to a branch pipe branching from one penstock (single pipe line). This relates to a method for controlling hydraulic machinery in power plants.

(Prior art) Pumped storage power plants are constructed for the purpose of maintaining the snow supply balance of electricity by generating electricity or pumping water according to the power system snow supply status, and therefore do not match the input or output required by the power system. It is necessary to operate each hydraulic machine accordingly.

With conventional control technology, when controlling multiple pump turbines installed in branch pipes branching from a single penstock, all or the required number of machines are always operated in the same way, thereby reducing power in the system. We have made adjustments (Unexamined Japanese Patent Publication No. 1986-
80481. (See No. 30482).

In this h method, the head loss generated in the waterway during power generation or pumping operation is determined by the total flow rate flowing within the entire length from the upper pond to the water turbine. Therefore, when operating a water turbine, 1-
Power generation can only be performed using the effective head that is calculated by subtracting the total head loss in the waterway from the apparent head difference between the pond and the lower pond, and the head cannot be used self-effectively. In addition, in pumping operation, water must be pumped with a lift equal to the apparent static head plus the total head loss in the waterway, which requires an additional shaft input from the pump.

(Problems to be Solved by the Invention) As mentioned above, in a pumped storage generator in which a plurality of hydraulic machines such as pump turbines are connected to a single pipeline, if all units are operated in the same way, the power generation operation and the pumped storage operation will not be the same. In either case, operation must be carried out while covering the head loss equivalent to the total number of units or the flow rate used in the entire waterway from the upper reservoir to the lower reservoir.

[Structure of the invention]

(Means for Solving the Problems) The present invention has been made to eliminate the above-mentioned drawbacks in the background art, and the present invention has been made in order to eliminate the above-mentioned drawbacks in the background art. In a branch channel pumped storage power plant that is connected to a pump-turbine, etc., when the pump pumping operation by some pump-turbine shade and the hydro-turbine power generation operation by other pump-turbine etc. are performed at the same time, the upper pond and When detecting a static head difference, which is a water level difference between The present invention is characterized in that a relative difference between the power generation flow rate of the machine and the power generation flow density of the pump is detected and transmitted to a guide vane control device of the pump pumping operation machine, and corresponding control of the guide vane opening degree to the static head difference is performed in accordance with the relative difference. .

(Function) As described above, the present invention is designed to operate a branch channel pumped storage power plant in which a plurality of hydraulic machines such as pump-turbines are connected to a single pipeline, without making the operation mode of each hydraulic machine the same, and to generate power from a certain machine. Since the machine operates while pumping other machines, the flow rate flowing through the single pipe as a whole is reduced.
Head loss during power generation and pumping operations for each machine is reduced, and by adjusting the amount of power generation and pumping of each machine, the flow rate flowing through the single pipe can be adjusted, allowing each machine to It is possible to generate an appropriate growth drop and lift, and each machine can be operated under optimal conditions.

The reason for this will be explained below. For convenience of explanation, the end of the single-line pipe leading to the pond is divided into two branch pipes, and one pump water turbine (#1 unit, #2 unit) is installed in each of these branch pipes. Let's talk about an example.

Now, Unit #1 is in power generation operation, and the water it uses is Q, and Unit 62 is in pumping operation, and the amount of water it pumps is Q.The flow rate ΔQ in the single pipe is ΔQ-Q, -Qp (1).

Here, if the water head loss in the single pipe pipe is △H, the water loss head in the branch pipe for #1 unit is △HIt, and the water head loss in the branch pipe for #2 unit is △H1-, then the effective head Ht of each pump-turbine and The lifting height H2 is H-H-ΔH-ΔH... (2) t St l It) 1
−H+ΔH+ΔH−<3) p st I Ip.

In general, in pumped storage power plants with branch pipes, in order to reduce civil engineering costs, a single pipe is often used up to just before the hydraulic machinery, and the length of the branch pipe is much longer than that of a single pipe. short. Therefore, the head loss within the pipe is much larger in a single pipe than in a branch pipe.

In the conventional technology (all units operate in the same mode), for example, when a flow rate of Q is allowed to flow through each pump-turbine during power generation operation, the loss of water head ΔH10 that occurs in a single pipe line is determined by the fact that each unit operates in a different mode. In the case of the present invention (power generation flow rate Qt)
Since the head loss is proportional to the square of the flow rate, it becomes ΔH−ΔHX (2Qt/Qt) −4·ΔH1 (4). Further, the effective head Ht from the upper pond to the lower pond is Hl - H-4 △H1 - △H1t (5) It. Similarly, the head H borne by each pump-turbine during pumping operation is H−H+4 ΔH, +ΔHI, . . . (6) st.

As mentioned above, a single line pipe is generally much longer than a branch pipe, so the above ΔH1 is smaller than ΔH, ΔH1p.
much larger than. Furthermore, if the operation of Q, -Q, is performed according to the present invention on It, 1 is obtained.
The flow rate flowing through the pipe line becomes O, and the head loss of the single pipe line becomes O.

Therefore, the effective head and head of each machine are H-H-△
H・(7) L sL It H−H+ΔH (8) p sL It Therefore, a generator operating machine can obtain a higher effective head and can generate economical power, and a pumped storage generator can generate electricity at a lower head. operation becomes possible, and the burden of input electric power is reduced.

In addition, by adjusting the flow rates of the power generator and pumped storage generator, the effective head or head that can be generated from the levels of the upper and lower reservoirs of the pumped storage power generation plant can be freely selected, so the optimum head can be selected depending on the situation. This makes it possible to drive.

(Example) Hereinafter, the present invention will be described in detail with reference to the drawings.

Figure 2 is a schematic diagram of the branch waterway system, with one pipe line 2 in the upper pond.
is connected, and after passing through the surge tank 3, it is split into a branch pipe 4.5. A pump water wheel 6 and a pump water wheel 7 are connected to each branch pipe, and a generator 71i electric motor (not shown) is attached to each pump water via a transmission shaft. Also,
Guide vanes (not shown) are arranged in each pump turbine 6.7 to change the opening degree of the water port. The downstream side of each pump-turbine is connected to a lower pond 8.

A flow meter 9.10 is installed in the single pipe line 2 and each branch pipe line 4.5.
．． 11 are connected. Further, water level detection devices 12 and 13 are installed in each of the 1-pond 1 and the lower pond 8.

FIG. 1 shows an example of the operation control configuration in the h° method of the present invention, in which the total flow is 9.10.11 and the water level detection device 12.
The signal from 13 is inputted to the arithmetic and control unit 14, which calculates the optimum flow aQ, ,Q.

The calculation results are calculated by the guide vane control device 15.
16 to control the opening degrees of guide vanes 17 and 18 of the pump driving machine and the water turbine driving machine.

In the pumped storage power plant having the above configuration, when adjusting power according to power supply and demand, first, depending on the state of power supply and demand, it is determined whether power is to be balanced through power generation operation or pumped storage operation.

Next, from the static head difference Hst measured by the upper pond water level riser 12 and the lower pond water level detector 13, the optimum head or lift for the required operation mode at that time is selected.

The arithmetic and control unit 14 calculates the optimal flow rate for each pump. The flow rate flowing through the single-line pipe is determined by equation (1), and the a-effective head H5 and pumped water H2 of each turbine operating machine and pump operating machine are determined by equations (2) and (3), respectively.
From these formulas, M suitable head or i!
It is sufficient to select the flow rate Qt, Q, for obtaining a culm. Once the flow rates are calculated by the arithmetic and control unit 14, guide vane opening commands corresponding to these flow rates are sent to the guide vane control unit 15°1.
6 to control the opening degree of the guide vane 17 of the pump driving machine and the guide vane 18 of the water turbine driving machine.

With the above operating method, the pump water turbines 6 and 7 are operated under the optimum operating conditions according to the power supply and demand at the time, and the power can be balanced.

〔Effect of the invention〕

According to the present invention, in a branch channel pumped storage power plant in which a plurality of pump turbines, etc. are connected to a single pipeline, by simultaneously performing power generation operation and pump operation of each hydraulic machine, the upper and lower pond levels at that time are It is possible to operate under the optimum head or head depending on the power supply and demand regardless of the situation.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an example of the operation control configuration of the method of the present invention, and FIG. 2 is a schematic diagram of a configuration example of a pumped storage power plant having a branch waterway to which the present invention is applied. 1...Upper pond, 2...1 pipe line, 3...surge tank, 4...branch pipe, 5...branch pipe, 6...#1 unit pump submerged, 7...・#2 pump water weight 8...
Lower pond, 9-11...Flowmeter, 12.13...Water level detector.

Claims (1)

[Scope of Claims] 1. A branch waterway pumping system in which a waterway is led from the upper pond by a single pipeline, branching off midway and connected to a plurality of pump-turbines or water-turbines and pumps (hereinafter referred to as pump-turbines, etc.) At a power plant, when pumping water by some pump-turbines and generating power by other pump-turbines are carried out simultaneously, the static head, which is the water level difference between the upper and lower ponds, is detected, and the pump When transmitting the information to the guide vane control device of the pumping operation machine to perform corresponding control of the guide vane opening degree, the relative difference between the pumping flow rate of the pump pumping operation machine and the generated flow rate of the water turbine generator operation machine is detected and the pump A method for controlling the steady operation of a pump in a branch waterway pumped storage power plant, characterized in that the information is transmitted to a guide vane control device of a pumping storage operating machine, and the opening degree of the guide vane is controlled in response to the static head difference in accordance with the relative difference. 2. The detected static head and relative difference are also transmitted to the guide vane control device of the water turbine generator operating machine, and the guide vane opening degree is controlled in response to the static head according to the relative difference, thereby controlling the actual head during operation. A pump steady operation control method for a branch waterway pumped storage power plant according to claim 1, characterized in that the water turbine power generation operation is performed in accordance with the above. 3. When the pumping flow rate exceeds the power generation flow rate, the pumping flow rate is equal to or lower than the power generation flow rate based on a predetermined appropriate opening relationship with respect to the static head. In some cases, the guide vane opening degree is controlled in response to the static head difference based on a predetermined appropriate opening relationship that is different from the appropriate opening relationship with respect to the static head difference. A pump steady operation control method for a branch waterway pumped storage power plant according to claim 1 or 2.