Control method for pumped-storage generation device

Abstract

The present invention makes it possible to adjust the rotation speeds of a pump-turbine runner and a generator motor rotor so as not to be largely changed when a guide vane is fully closed, by making a guide vane closure rate adjustable by means of guide vane opening at the time of disconnecting a parallel circuit breaker after break opening or breaking in a closure rate of a double-stage linear guide vane in which one breaking is provided in the middle of the closure rate from opening to a full close of the guide vane during a stop operation of a pumping stop method of a pumped-storage generation device. A transition time from a switching operation of the pumping operation into the power generation operation to the power generation operation of the pumped-storage generation device can be shortened, and a change amount of the transition time from the pumping operation to the power generation operation due to the guide vane opening at the time of disconnecting the parallel circuit breaker or the difference between the rotation speeds of the pump turbine runner and the power generation motor rotor can be made small.

Description

Control method for pumped storage power generation device

[0001] The present invention relates to control for rapidly switching from pumping operation to power generation operation of a constant-speed or variable-speed pumped-storage power generation plant. When a command to switch from pumping operation to power generation operation is issued, the parallel circuit breaker is immediately opened to switch to input shutdown. In this case, a two-stage linear guide vane closing rate is provided with a slack in one position midway between the guide vane opening at the time of stop operation and the closing rate to fully closed, and the slack opening is adjustable depending on the guide vane opening at the time of parallel-off of the parallel circuit breaker. The larger the guide vane opening at the time of parallel-off, the smaller the slack opening is. By making the guide vane opening smaller, the rotational speed of the pump turbine runner and generator motor rotor when the guide vanes are fully closed can be adjusted so that it does not change significantly, regardless of whether the pumped-storage power generation device is a constant-speed or variable-speed pumped-storage power generation device, even if the guide vane opening varies greatly when the parallel circuit breaker is disconnected.This relates to a method for controlling rapid switching from pumping operation to power generation operation of a pumped-storage power generation device, which shortens the time from when a command to switch from pumping operation to power generation operation is issued until the rotation of the rotor stops and power generation can be started, and reduces the amount of change due to the guide vane opening when the parallel circuit breaker is disconnected.

[0002] A pump-turbine of a pumped-storage power generation system has a runner connected to a main shaft that rotates within a runner chamber sandwiched between an upper cover and a lower cover, a plurality of movable guide vanes provided on the outer periphery of the runner chamber to adjust the flow rate of water flowing in and out of the runner chamber, a speed ring having a plurality of stationary stay vanes on the outer periphery of the movable guide vanes to adjust the flow direction, allowing water to flow in and out between the runner and a casing installed on the outermost periphery of the pump-turbine, an inlet valve for closing the flow path for flowing water in and out of the casing, a lower draft pipe provided at the bottom of the runner chamber to guide the water flowing in and out of the runner chamber to the lower pond of the pumped-storage power plant, and a generator-motor connected to the main shaft. In a conventional control method for a pumped-storage power generation plant when it is shut down during pumping operation, a linear guide vane closing rate or a two-stage linear guide vane closing rate with a fixed intermediate bended opening is used as the closing rate for changing the guide vane opening from fully closed during the shut-down operation. Therefore, when a command to switch from pumping operation to power generation operation is issued, the parallel circuit breaker is opened to switch to input shutdown, and the rotational speed of the pump-turbine runner and generator-motor rotor when the guide vanes are fully closed changes significantly depending on the guide vane opening when the parallel circuit breaker is opened or the rotational speed of the pump-turbine runner and generator-motor rotor when opened. As a result, the time from when the parallel circuit breaker is opened until the rotation of the pump-turbine runner and generator-motor rotor stops varies significantly depending on the operating conditions at the time of parallel-off. As an example of the pump input cutoff transient phenomenon of a pumped storage power generation system, Figure 5 shows an example of Figure 129 Pump Input Cutoff Transient Phenomena shown in Mechanical Engineering Handbook B, Application Edition B5 Application Edition 2-9-3 Transient Phenomena, published by the Japan Society of Mechanical Engineers. In the example of the pump input cutoff transient phenomenon shown in Figure 5, the guide vanes are closed at a two-stage linear guide vane closing rate, with a small bended sash at one point midway between the guide vane opening at input cutoff and the fully closed sash. This bended sash opening is constant regardless of the total head at input cutoff, the guide vane opening, and other conditions. Therefore, when the guide vanes are fully closed, the rotational speed of the pump-turbine runner and generator-motor rotor is 40% or more.

[0003] The rotational speed of the runner and generator motor rotor is mainly slowed down by the sliding friction resistance caused by the runner stirring up the water trapped in the runner chamber when the guide vanes are fully closed, and after the speed has been reduced to a certain extent, it takes a long time for the generator motor to stop due to the operation of the electric brake and mechanical brake.

[0004] One example of a control method for rapidly switching from pumping operation to power generation operation in a pumped-storage power plant is shown in Figure 5 of "Hydroelectric Power Generation Technology Contributing to Improving the Quality of Power Systems" in Toshiba Review Vol. 58 No. 7 (2003). This method uses a hydraulic brake, which does not completely close the guide vanes and applies a high-pressure water flow in the opposite direction to the rotational direction to the runner. Test results using a model pump-turbine have verified that this method is capable of quickly switching from pump direction rotation to turbine direction rotation. However, in an actual pumped-storage power plant, the tilting pads of the thrust bearing do not always operate normally due to the inertial flow of lubricating oil in the oil tank when the rotational direction is rapidly reversed, raising concerns that this could lead to damage to the thrust bearing.

[0005] As mentioned above, Figure 5 shows an example of pump input cutoff transient phenomenon shown in Figure 129, Mechanical Engineering Handbook B, Application Edition B5 Application Edition 2, 9, 3 Transient Phenomena, published by the Japan Society of Mechanical Engineers. Figure 5 shows an example of pump input cutoff transient phenomenon of a constant speed pumped storage power generation plant, and the rotational speed when the guide vanes are fully closed is approximately 44% of the rated rotational speed.

[0006] FIG. 6 shows a configuration diagram of a guide vane servo motor closing circuit when the input of a conventional pumped storage power generation plant is cut off.

[0007] Reference numeral 1 denotes a logic function circuit, which determines whether the guide vane servo motor stroke (hereinafter sometimes abbreviated as GVS) value is greater than or less than the bending GVS at the time of input interruption, and outputs 1.0 when the GVS value is greater than or equal to the bending GVS, and outputs 0.0 when the GVS value is less than the bending GVS.

[0008] Reference numeral 2 denotes a logical multiplier, which performs a logical multiplication of the output of the logic function circuit 1 and a closing command from the governor and outputs the result.

[0009] Reference numeral 3 denotes a selection function circuit, which selects and outputs the guide vane pressure distributing valve flow characteristics of GVS 100% to buckled GVS when the output signal of the logical multiplier 2 is 1.0.

[0010] Reference numeral 4 denotes a logic function circuit, which determines whether the GVS value is less than or greater than the break GVS at the time of input interruption, and outputs 1.0 when the GVS value is less than the break GVS, and outputs 0.0 when the GVS is greater than or equal to the break GVS.

[0011] Reference numeral 5 denotes a logical multiplier, which performs a logical multiplication of the output of the logical function circuit 4 and the closing command from the governor and outputs the result.

[0012] Reference numeral 6 denotes a selection function circuit, which selects and outputs the guide vane pressure distributing valve flow characteristics between the buckling GVS and GVS 0% when the output signal of the logical multiplier 5 is 1.0.

[0013] The reference numeral 7 denotes an adder, which adds together the guide vane pressure distributing valve flow characteristics for GVS 100% to buckled GVS selected by the selection function circuit 3 and the guide vane pressure distributing valve flow characteristics for buckled GVS to GVS 0% selected by the selection function circuit 6 and outputs the result.

[0014] Reference numeral 8 denotes a guide vane servo motor, and the GVS is closed in accordance with the flow rate characteristics of the guide vane pressure distributor valve output from the adder 7.

[0015] FIG. 7 is a characteristic diagram showing an example of the pumping operation range of an adjustable speed pumped storage power generation system.

[0016] In FIG. 7, in the variable speed pumping operation range, the rotation speed N is equal to the rated rotation speed N Ｏ The GVS varies from 50% to a maximum of approximately 88%, and the motor input P varies in the range of approximately 65% ​​to 100% of the maximum motor input Pmax.

[0017] Figure 8 shows the closing characteristics of the guide vane servo motor stroke during input interruption for a conventional pumped-storage power plant. The closing characteristics of the guide vane servo motor stroke during input interruption include a single step of bending between the GVS at the time of input interruption and 0% GVS. The step from the GVS at the time of input interruption to the bending GVS is 8 seconds per 100% GVS, and the bending GVS is 20%. The step from the bending GVS to 0% GVS is 20 seconds per 100% GVS. As shown in Figure 9 (described later), the closing characteristics are set to ensure a pumping direction rotation speed of at least 30% when the GVS reaches 0% GVS in order to prevent damage to the thrust bearing due to improper tilt reversal of the thrust bearing tilting pad when the runner rotation reverses from the pumping operation direction to the power generation operation direction during the GVS closing process.

[0018] FIG. 9 is a diagram showing an example of a rotational speed analysis result when the stroke of the guide vane servo motor is fully closed in an input interruption analysis example of a conventional pumped storage power generation plant.

[0019] In this example of analysis results, the guide vane servo motor stroke closing characteristics at input interruption shown in FIG. 8 were applied, and input interruption analysis was performed at maximum motor input Pmax, rotation speed N = 100%, and minimum motor input Pmin with GVS = 50% for the minimum static head and the maximum static head in the characteristics diagram of the pumping operation range of the adjustable speed pumped storage power generation plant shown in FIG. 7.

[0020] In this analysis example, the rotational speed analysis results when the GVS is fully closed range from approximately 41% to approximately 45% at maximum motor input Pmax, from approximately 48.5% to approximately 50% at rotational speed N = 100%, and are constant at approximately 63% at minimum motor input Pmin. Therefore, the minimum value of the rotational speed analysis results when the GVS is fully closed is approximately 41% at maximum motor input Pmax with minimum static head, which satisfies the pumping direction rotational speed of at least 30% when GVS reaches 0% in order to prevent the runner rotation from reversing from pumping operation to power generation operation while the GVS is closing.

[0021] Japanese Unexamined Patent Publication No. 4-159457

[0022] In a conventional method for rapidly switching over from pumping operation to power generation operation of a pumped storage power generation plant, the parallel circuit breaker is opened immediately when a command to switch over from pumping operation to power generation is issued, and the input is shut off. However, as shown in Figures 5 and 9, in order to prevent the runner rotation from reversing from the pumping operation direction to the power generation operation direction while the GVS is being closed, the rotation speed in the pumping direction when the GVS reaches 0% is maintained at a minimum of 30%, and in reality, a minimum value of 40% or more is maintained. However, because the rotation speed when the GVS reaches 0% is maintained at a minimum of 40% or more, it takes a long time for the rotation to stop even if the electric brake and mechanical brake are activated, and power generation is started only after a complete stop of rotation is detected. Therefore, it takes about 5 minutes or more to switch over from pumping operation to power generation operation, and it is difficult to speed up the operation any faster than this.

[0023] One control method proposed as a means to solve the above-mentioned problem is that disclosed in Patent Document 1. This is a control method for a pump-turbine when switching from pumping operation to power generation operation in response to a command to switch from pumping operation to power generation. After disconnecting the generator motor from the system during pumping operation, the guide vane opening is maintained at a small opening, the pump-turbine rotational speed in the pumping direction is rapidly reduced, and the pump-turbine rotational speed is waited for to reverse to the power generation direction before switching to power generation operation.

[0024] As a result of verifying the effectiveness of applying the pump-turbine control method shown in Patent Document 1 when switching from pumping operation to power generation operation in response to a switching command, Figure 5 in Toshiba Review Vol. 58 No. 7 (2003) "Hydroelectric Power Generation Technology Contributing to Improving the Quality of Power Systems" shows that, as a result of verification using a model test device, the total switching time can be reduced to about half that of the conventional method.

[0025] However, when the switching from pumping operation to power generation operation shown in Patent Document 1 is applied, as mentioned above, the tilting pad of the thrust bearing may not always be able to tilt against the inertial flow of the lubricating oil in the oil tank due to the rapid reversal of the rotation direction, which may lead to damage to the thrust bearing. Therefore, after the thrust bearing is damaged, it is thought that the operation of the pumped storage power generation system may be hindered.

[0026] In order to solve the above problems, the present invention provides a one-stage bending GVS, which is provided between the GVS at the time of interruption and GVS 0% in the closing characteristics of the guide vane servo motor stroke when input is interrupted after a command to switch from pumping operation to power generation operation is given, and which is adjustable based on the GVS value at the time of input interruption, thereby reducing the difference in the runner rotation speed of the pump-turbine when the GVS is fully closed due to differences in the operating point when input is interrupted, and setting the maximum runner rotation speed of the pump-turbine when the GVS is fully closed to approximately 10% or less of the rated rotation speed, thereby shortening the time until rotation stops and reducing the variation in the time until rotation stops due to differences in the operating point when input is interrupted.

[0027] According to the present invention, when a command is issued to switch from pumping operation to power generation operation of a pumped-storage power generation plant having a pump turbine with movable guide vanes and a generator motor shaft-coupled to the pump turbine, the time until rotation stops can be shortened and the variation in the time until rotation stops due to differences in the operating point when input is cut off can be reduced.

[0028] FIG. 1 is a configuration diagram of a guide vane servo motor closing circuit when input is interrupted after a command to switch from pumping operation to power generation operation of a pumped storage power generation apparatus according to an embodiment of the present invention. FIG. 2 is a diagram showing the closing characteristics of the guide vane servo motor stroke when input is interrupted after a command to switch from pumping operation to power generation operation of a pumped storage power generation apparatus according to an embodiment of the present invention. FIG. 3 is a diagram showing an example of setting a buckling GVS in the closing characteristics of the guide vane servo motor stroke when input is interrupted after a command to switch from pumping operation to power generation operation of a pumped storage power generation apparatus according to an embodiment of the present invention. FIG. 4 is a diagram showing an example of a rotational speed analysis result when the guide vane servo motor stroke is fully closed in an example of input interruption analysis after a command to switch from pumping operation to power generation operation of a pumped storage power generation apparatus according to an embodiment of the present invention. FIG. 5 is a diagram showing an example of transient phenomena when input is interrupted of a pumped storage power generation apparatus according to a conventional embodiment. FIG. 6 is a configuration diagram of a guide vane servo motor closing circuit when input is interrupted of a conventional pumped storage power generation apparatus. FIG. 7 is an example of a characteristic diagram of the pumping operation range of an adjustable-speed pumped storage power generation apparatus. FIG. 8 is a diagram showing the closing characteristics of the guide vane servo motor stroke when input is interrupted of a conventional pumped storage power generation apparatus. FIG. 9 is a diagram showing an example of a rotational speed analysis result when the stroke of the guide vane servo motor is fully closed in an input interruption analysis example of a conventional pumped storage power generation plant.

[0029] A control method for a pumped storage power generation system according to the present invention, more specifically, a control method for switching from pumping operation to power generation operation of a pumped storage power generation system, will be described in detail below with reference to the accompanying drawings. However, the present invention is not limited to these embodiments.

[0030] Fig. 1 is a diagram showing the configuration of a guide vane servo motor closing circuit when the input is cut off after a command to switch from pumping operation to power generation operation of a pumped storage power generation plant according to an embodiment of the present invention. In Fig. 1, the same reference numerals as those in Fig. 6 used to explain the conventional example indicate the same or corresponding components.

[0031] The configuration in FIG. 1 is almost the same as the configuration of the conventional pumped storage power generation system shown in FIG. 6, except that the configuration in FIG. 1 has an additional circuit that makes it possible to adjust the bending of one stage of the guide vane servo motor stroke closing characteristics at input interruption between the GVS at interruption and GVS 0% based on the GVS value at the time of input interruption as shown below.

[0032] Reference numeral 9 denotes a negation function circuit. An ON / OFF signal of the parallel circuit breaker is input to the negation function circuit 9, which outputs 0.0 when the parallel circuit breaker is ON and outputs 1.0 when the parallel circuit breaker is OFF.

[0033] Reference numeral 10 denotes a timer. The output of the NOT function circuit 9 is input to the timer 10, and when the input is 1.0, the timer 10 outputs 1.0 for the timer set time T1. When the input is other than 1.0, the timer 10 constantly outputs 0.0. The timer set time T1 is set to be equal to or less than the GVS closed immobility time immediately after the input interruption occurs.

[0034] A digital / analog converter 11 is designated by the reference numeral 11. The digital / analog converter 11 converts the digital value output from the timer 10 into an analog value and outputs the analog value.

[0035] Reference numeral 12 denotes a multiplier. The multiplier 12 outputs the result of multiplying the GVS, which is the output of the guide vane servo motor 8, by the output value of the digital / analog converter 11. Therefore, the multiplier 12 outputs the GVS value for the timer set time T1 of the timer 10 after the parallel circuit breaker is turned OFF.

[0036] An ON-OFF signal generator 13 is designated by the reference numeral 13. The ON-OFF signal generator 13 outputs 1.0 when the GVS value, which is the output of the guide vane servo motor 8, is several percent or more, and outputs 0.0 when it is less than that.

[0037] A multiplier 14 is indicated by a reference numeral 14. The multiplier 14 outputs the result of multiplying the output of the ON-OFF signal generator 13 by the output of a maximum value selection function circuit 15, which will be described later.

[0038] Reference numeral 15 denotes a maximum value selection function circuit. The maximum value selection function circuit 15 compares the output value of the multiplier 12 with the output value of the multiplier 14 and outputs the maximum value. Due to the functions from the negation function circuit 9 to the maximum value selection function circuit 15 described above, the GVS value at the time of input interruption is output from the multiplier 12 for the timer set time T1 of the timer 10, and the ON-OFF signal generator 13 outputs 1.0 when the GVS value is several percent or more. Therefore, when the GVS value is several percent or more, the GVS value at the time of input interruption is self-maintained by the multiplier 14 and the maximum value selection function circuit 15.

[0039] Reference numeral 16 denotes a break GVS generation function circuit. An example of the setting of the break GVS generation function circuit 16 is shown in FIG.

[0040] 2 is a diagram showing the closing characteristics of the guide vane servo motor stroke when the input is cut off after a command to switch from pumping operation to power generation operation of a pumped storage power generation plant according to an embodiment of the present invention. The closing characteristics of the guide vane servo motor stroke when the input is cut off include a step of bending between the cut-off GVS and 0% GVS, with the time from the cut-off GVS to the bending GVS being 12 seconds / 100% GVS. An example of the setting of the bending GVS is shown in FIG. 3, which will be described later, and the time from the bending GVS to 0% GVS being 27 seconds / 100% GVS.

[0041] Figure 3 shows an example of a setting of the buckling GVS in the closing characteristics of the guide vane servo motor stroke when the input is shut off after a command to switch from pumping operation to power generation operation of a pumped storage power generation plant according to an embodiment of the present invention. In this example, the buckling GVS is constant at 50% when the shutoff GVS is 50% or less, linearly decreases from 50% to 15% when the shutoff GVS is 50% or more and 90% or less, and remains constant at 15% when the shutoff GVS is 90% or more. By applying the buckling GVS setting in the closing characteristics of the guide vane servo motor stroke when the input is shut off after a command to switch from pumping operation to power generation operation of the pumped storage power generation plant shown in Figure 2 to the buckling GVS setting in the closing characteristics of the guide vane servo motor stroke when the input is shut off after a command to switch from pumping operation to power generation operation of the pumped storage power generation plant shown in Figure 3, the maximum GVS closing time at the maximum shutoff GVS of 100% is 19.5 seconds.

[0042] FIG. 4 is a diagram showing an example of a rotational speed analysis result when the guide vane servo motor stroke is fully closed in an input cutoff analysis example after a command to switch from pumping operation to power generation operation of a pumped storage power generation plant according to an embodiment of the present invention.

[0043] In this example of analysis results, a buckling GVS setting was applied to the closing characteristics of the guide vane servo motor stroke when input is cut off after a command to switch from pumping operation to power generation operation in Figure 2 and the closing characteristics of the guide vane servo motor stroke when input is cut off after a command to switch from pumping operation to power generation operation in Figure 3, and input cutoff analysis was performed at the maximum motor input Pmax, when the rotation speed N = 100%, and when the minimum motor input Pmin with GVS = 50%, for the minimum static head and the maximum static head, as in Figure 9, in the characteristic diagram of the pumping operation range of the adjustable speed pumped storage power plant shown in Figure 7.

[0044] The rotational speed analysis results for the GVS fully closed in this analysis example range from 7.1% to 7.4% at maximum motor input Pmax, are constant at approximately 11% at rotational speed N = 100%, and range from 7.7% to 9.8% at minimum motor input, so even if the GVS at shutoff differs by 10% or more, the difference in rotational speed when the GVS is fully closed is less than 5%. Thus, the rotational speed analysis results for the GVS fully closed in this analysis example range from 7.1% to 11%, which is approximately 1 / 6 of the maximum value and a small variation of 2.1% compared to the range of approximately 41% to approximately 63% in the rotational speed analysis results for the GVS fully closed in the conventional analysis result example shown in Figure 9.

[0045] Therefore, in the guide vane servo motor closing circuit when input is cut off after a command to switch from pumping operation to power generation operation of a pumped storage power generation plant configured as shown in Figure 1, by applying the buckling GVS setting in the guide vane servo motor stroke closing characteristics when input is cut off after a command to switch from pumping operation to power generation operation of Figure 2 and the guide vane servo motor stroke closing characteristics when input is cut off after a command to switch from pumping operation to power generation operation of Figure 3, as described above, the maximum GVS closing time is 19.5 seconds or less, and the rotation speed when the GVS is fully closed is approximately 11% or less, and it is expected that the time from when the input is cut off until rotation is stopped by the operation of the electric brake and mechanical brake will be approximately 30 seconds or less.

[0046] Furthermore, even when a constant-speed or variable-speed pumped-storage power plant is not rapidly switched from pumping operation to power generation operation, by adjusting the closing rate of the guide vane servo motor stroke closing characteristics when input is cut off after a command to switch from pumping operation to power generation operation is issued as shown in Figure 2 and by adjusting the buckling GVS setting in the closing characteristics of the guide vane servo motor stroke when input is cut off after a command to switch from pumping operation to power generation operation as shown in Figure 3 and applying them to an emergency stop and input cutoff, it is possible to reduce the difference in the rotational speed of the pump-turbine runner when the GVS is fully closed due to differences in the operating point when input cutoff occurs, and to speed up restart to pumping operation or power generation operation, including phase modifying operation.

[0047] 1, 4: Logic function circuit; 2, 5: Logical multiplier; 3, 6: Selection function circuit; 7: Adder; 8: Guide vane servo motor; 9: Negation function circuit; 10: Timer; 11: Digital value / analog value converter; 12, 14: Multiplier; 13: ON-OFF signal generator; 15: Maximum value selection function circuit; 16: Bend guide vane servo motor stroke generation function circuit.

Claims

1. When a command is issued to switch from pumping operation to power generation operation of a pump-type power generation system having a pump turbine equipped with a movable guide vane and a generator motor shaft-coupled to the pump turbine, the parallel circuit breaker is immediately opened when the command to switch from the pumping operation to the power generation operation is issued, and the input is cut off, and in a two-stage linear guide vane closing rate in which a bend is provided at one point midway between the guide vane opening at the time of stopping operation and the closing rate at the time of full closure, the bend opening is adjustable according to the guide vane opening at the time of parallel-off of the parallel circuit breaker, and the greater the guide vane opening at the time of parallel-off, the smaller the bend opening is set, so that the guide vane opening at the time of parallel-off of the parallel circuit breaker is fully opened. a control method for switching from pumping operation to power generation operation of a pumped-storage power generation apparatus, characterized in that the rotational speeds of the pump-turbine runner and generator motor rotor when the guide vanes are fully closed can be adjusted so as not to change by more than 5% of the rated rotational speed for either a constant speed or variable speed pumped-storage power generation apparatus even if the opening degree of the guide vanes differs by 10% or more, and the amount of change in the time from when the switch command from the pumping operation to the power generation operation is issued to when the rotation of the rotor stops and power generation can be started due to the guide vane opening degree at parallel-off is set to less than 5% of the rated rotational speed, and switching from the pumping operation to the power generation operation is performed.

2. A control method for switching from pumping operation to power generation operation of a pumped-storage power generation apparatus as claimed in claim 1, characterized in that, when a command to switch from the pumping operation to the power generation operation is received, the parallel circuit breaker is opened immediately after receiving a command signal to switch from the pumping operation to the power generation operation, and a guide vane is closed in accordance with a guide vane closure determined in accordance with the guide vane opening at the time of parallel-off of the parallel circuit breaker or the rotational speed of the runner of the pump-turbine and the generator-motor rotor at the time of parallel-off, but an inlet valve provided between the pump turbine and the iron pipe is not closed, and after it is detected that the rotational speed of the rotor of the pumped-storage power generation apparatus has stopped, the guide vane is opened to the power generation start-up opening to start power generation, and after the rotational speed of the rotor of the pumped-storage power generation apparatus has reached the parallel rotation speed of the parallel circuit breaker, the parallel circuit breaker is paralleled, thereby switching from the pumping operation to the power generation operation.