JP2022109015A - Transformation system, control method for transformation system, and electric railway system - Google Patents

Abstract

To provide a transformation system using both a substation with a low power reception capacity and a power storage device, which is low-cost, highly reliable and can secure power performance required for a train to travel while suppressing power reception from a power system to a rated capacity or less.SOLUTION: A transformation system includes: a first AC-DC power conversion device 101 that converts AC power from a power system into DC power: a first DC power conversion device 102 that converts DC power from the first AC-DC power conversion device; and a second DC power conversion device 103 that performs power transmission/reception to/from a feeder wire. A power storage device 104 is connected between the first DC power conversion device and the second DC power conversion device to charge electric power from the feeder wire via the second DC power conversion device and to discharge electric power to the feeder wire via the second DC power conversion device. The first DC power conversion device is controlled by an output having a rated capacity or less, and control is executed so that discharge from the power storage device compensates for shortage of power in the second DC power conversion device.SELECTED DRAWING: Figure 1

Description

The present invention relates to the configuration and control of a substation system, and more particularly to a technique effectively applied to a railway power system for operating railway vehicles.

A large-capacity substation facility is necessary to construct a railway system in an urban area with a large number of trains. In general, substations with a power receiving capacity of 6000 kW or more become special high-voltage power receiving infrastructure that requires power receiving infrastructure from the transmission system using steel towers or buried pipes, which incurs enormous costs.
Also, from the viewpoint of rail ground potential suppression, it is important to reduce the distance between substations. However, in cities of emerging countries, it is very difficult to build a feeder system considering the cost and equipment of power receiving infrastructure capacity.

In addition, considering local lines with low power receiving infrastructure capacity, if a large amount of power is required, it is necessary to build a power network by transmitting power using transmission lines from substations that receive extra high voltage power. Maintenance of transmission lines requires a great deal of cost.

Under these circumstances, it is important to reduce the substation to 2,000 kW or less, which is a high-voltage power receiving system, so that the substation can receive power from power poles and other distribution systems that have low power receiving infrastructure construction costs, and make it possible to supply power. That is.

As a background art of this technical field, there is a technique such as Patent Document 1, for example. Patent Literature 1 discloses, as one method for solving the above problem, a system that uses a power storage device in addition to lowering the power receiving capacity of a substation.

JP 2010-58565 A

The technique of Patent Document 1 is controlled to charge the regenerated power as much as possible in order to suppress the capacity of the power storage device and use the regenerated power efficiently.

However, when regenerative power cannot be obtained and the amount of charge in the power storage device decreases, output from the power storage device cannot be obtained, resulting in a decrease in output from the substation and affecting operation. there is a possibility. In addition, since the continuous charging and discharging of the power storage device also affects the life of the power storage device itself, the overload capacity, which is the amount of charge and discharge power that can be output within a certain continuous time range, is generally determined.

Therefore, when the regenerative electric power is charged as much as possible within a certain continuous time range, the discharge time within that continuous time range is limited. As a result, the power that requires the assistance of the power storage device cannot be obtained, resulting in a decrease in output from the substation, which may affect operation.

Therefore, the object of the present invention is to secure the power performance necessary for trains to run while suppressing the power received from the power system to below the rated capacity in a substation system that uses both a substation with a low power receiving capacity and a power storage device. To provide a possible low-cost and highly reliable substation system and its control method.

In order to solve the above problems, the present invention provides a first AC/DC power converter that converts AC power from a power system into DC power, and a DC unit that converts the DC power from the first AC/DC power converter into DC power. A first DC power conversion device that converts to DC power, a second DC power conversion device that transmits and receives power to and from a feeder, and between the first DC power conversion device and the second DC power conversion device , and charges power from the feeder line via the second DC power converter and discharges to the feeder line via the second DC power converter. and a device for controlling the first DC power conversion device with an output equal to or less than the rated capacity, and compensating for the shortage of power in the second DC power conversion device by discharging from the power storage device. It is characterized by controlling.

Further, the present invention provides, in an electric railway system using the above-described substation system, a second AC/DC power converter for converting AC power from a power system into DC power, and a DC power converter from the second AC/DC power converter. a first rectifier that converts electric power and outputs power to a feeder; It is characterized by controlling the voltage to be lower than the voltage that

Further, the present invention is a method for controlling a substation system using both a substation and a power storage device, wherein AC power from the substation is converted into DC power by an AC/DC power converter, and DC power is converted to DC power in the DC section by a first DC power converter, and the output of the first DC power converter is controlled below the rated capacity, and from the first DC power converter The DC power is converted to DC power to be transmitted to the feeder by the second DC power converter, and the shortage of power in the second DC power converter is compensated by discharging from the power storage device. characterized by

According to the present invention, in a substation system that uses both a substation with a low power receiving capacity and a power storage device, it is possible to secure the power performance necessary for trains to run while suppressing the power received from the power system to below the rated capacity. A low-cost and highly reliable substation system and its control method can be realized.

Problems, configurations, and effects other than those described above will be clarified by the following description of the embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows schematic structure of the substation system which concerns on Example 1 of this invention. FIG. 2 is a diagram showing the configuration of an energy control function 105 in FIG. 1; FIG. 3 is a diagram showing the configuration of a maximum discharge power calculation function 201 in FIG. 2; FIG. 3 is a diagram showing a configuration of an overload limiter discharge power calculation function 202 of FIG. 2; FIG. 5 is a diagram showing the configuration of overload limiter processing 404 in FIG. 4; FIG. 5 is a diagram showing the configuration of maximum discharge power determination processing 405 in FIG. 4. FIG. 3 is a diagram showing the configuration of a maximum output calculation function 204 in FIG. 2; FIG. 3 is a diagram showing the configuration of a maximum charge power calculation function 206 in FIG. 2; FIG. FIG. 3 is a diagram showing a configuration of an overload limiter charging power calculation function 207 in FIG. 2; FIG. 10 is a diagram showing a configuration of overload limiter processing 904 of FIG. 9; FIG. FIG. 10 is a diagram showing the configuration of maximum charging power determination processing 905 in FIG. 9; FIG. 3 is a diagram showing a processing flow of a charge power command calculation function 208 in FIG. 2; FIG. 2 is a diagram showing an example of charge/discharge control of the power storage device 104 of FIG. 1; FIG. 2 is a diagram showing an example of charge/discharge control of the power storage device 104 of FIG. 1; FIG. It is a figure which shows schematic structure of the railway electric power system which concerns on Example 2 of this invention. 15. It is a figure which shows the structure of the energy control function 1501 of FIG. FIG. 3 is a diagram showing a schematic configuration of a railway power system according to Example 3 of the present invention; 17. It is a figure which shows the structure of the energy control function 1701 of FIG. It is a figure which shows the example of the operation schedule concerning Example 3 of this invention. FIG. 18 is a diagram showing the configuration of a control decision function 1703 in FIG. 17; It is a figure which shows the charging/discharging control method based on Example 3 of this invention. FIG. 10 is a diagram showing a schematic configuration of a railway power system according to Embodiment 4 of the present invention; 23 is a diagram showing the configuration of an energy control function 2201 in FIG. 22; FIG. 23 is a diagram showing a processing flow of a control decision function 2202 in FIG. 22; FIG.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, in each drawing, the same configurations are denoted by the same reference numerals, and detailed descriptions of overlapping portions are omitted.

Embodiment 1 A transformer system and its control method according to Embodiment 1 of the present invention will be described with reference to FIGS. 1 to 14 . FIG. 1 is a configuration diagram of a substation system in this embodiment, solid lines represent connections between systems and facilities, and dotted lines represent information flows from each system and facilities.

As shown in FIG. 1, the substation system of this embodiment includes a first AC/DC power converter 101 that receives AC power from a power system and converts it to DC power, and a DC power converter that receives DC power from the first AC/DC power converter 101. A first DC power conversion device 102 that converts power into power in the DC section, a second DC power conversion device 103 that converts the power of the first DC power conversion device 102 and outputs it to a feeder line, It is connected between the first DC power converter 102 and the second DC power converter 103, and charges power from the feeder via the second DC power converter 103, and supplies the second DC power It has a power storage device 104 that discharges to the feeder via a converter 103 .

Further, based on the voltage 151 of the feeder line, the output power 152 of the second DC power converter 103, the charge amount 153 of the power storage device 104, and the rated power 154 of the first DC power converter 102, the It has an energy control function 105 that determines a control command 155 for the second DC power converter 103 and a control command 156 for the first DC power converter 102 .

The energy control function 105 will be described with reference to FIG.

The energy control function 105, as shown in FIG. , an overload limiter discharge power calculation function 202 that calculates the overload limiter discharge power limit 253 from the charge amount 153, and a minimum value selector 203, the maximum discharge power 252 and the overload limiter A function to set the smaller value of the discharge power limit 253 to the maximum discharge power 254 of the power storage device 104, the voltage 151 of the feeder line, the rated power 154, and the second supply start set in the energy control function 105 A maximum output calculation function 204 that calculates a maximum output power 256 of the first DC power converter 102 based on the voltage 255, and an adder 205 that calculates the maximum discharge power 254 of the power storage device 104 and the first DC power converter 102 is calculated as a control command 155 for the second DC power converter 103 .

Also, a maximum charging power calculation function 206 that calculates a maximum charging power 257 based on the feeder voltage 151 and the charging amount 153, and an overload limiter charging power limit 258 that calculates an overload limiter charging power limit 258 from the charging amount 153. The calculation function 207, the feeder voltage 151, the output power 152 of the second DC power converter 103, the rated power 154 of the first DC power converter 102, and the energy control function 105 are set. Based on regenerative charging start voltage 259 and charging power 260, charging power command calculation function 208 calculates charging power command 261, and minimum value selector 209 determines maximum charging power 257, overload limiter charging power limit 258 and charging power. The control command 156 of the first DC power converter 102 is calculated by calculating the minimum value from the commands 261 and multiplying the minimum value by (-1).

Here, the first supply start voltage 251 is the threshold voltage that determines the discharge from the power storage device 104, and the second supply start voltage 255 is the threshold voltage that determines the supply from the first DC power converter 102. . Moreover, it is desirable that the first supply start voltage 251≦the second supply start voltage 255 is established.

The maximum discharge power calculation function 201 will be described with reference to FIG.

The maximum discharge power calculation function 201, as shown in FIG. A function that determines whether the voltage is lower than the first supply start voltage 251 and outputs "1" if Yes and "0" if No as the output result 352, and outputs the maximum discharge power 351 by the multiplier 303. It consists of a function that calculates the product of the result 352 and outputs it as the maximum discharge power 252 of the power storage device 104 .

Note that the maximum discharge power table 301 may be any table as long as it shows the relationship between the state of charge (SOC) and the maximum discharge power. For example, as shown, it is configured in the form of a graph of state of charge (SOC) on the horizontal axis and maximum discharge power on the vertical axis.

The overload limiter discharge power calculation function 202 will be described with reference to FIG.

The overload limiter discharge power calculation function 202, as shown in FIG. A function to calculate the variable charge amount 452 by subtracting the charge amount 153 from the charge amount 451 one time before, and the maximum value selector 403 selects the larger one of the variable charge amount 452 and the "0" value on the discharging side. A function to output as a variable charge amount 453, an overload limiter process 404 for calculating an overload limiter judgment value 454 with the fluctuation charge amount 453 on the discharge side as an input, and an overload limiter discharge with the overload limiter judgment value 454 as an input It comprises a maximum discharge power determination process 405 based on an overload limiter that calculates the power limit 253 .

The overload limiter processing 404 will be described with reference to FIG.

As shown in FIG. 5, the overload limiter process 404 is obtained by multiplying the variable charge amount 453 on the discharge side by the charge amount of the power storage device 104 (not shown) and dividing by the operation cycle time of this process. A discharge current calculator 501 that calculates a discharge current 551 per unit time, a function that calculates the square of the discharge current 551 by a multiplier 502 to calculate a discharge current square value 552, and a subtractor 503 that calculates the discharge current square value 552. A function of calculating a discharge heat load 554 obtained by subtracting the heat cooling performance 553 per unit time of the power storage device 104 from 555 , the sum of the discharge heat loads 554 in the overload limiter calculation time range 555 is calculated, and the overload limiter calculation function 504 outputs the overload limiter judgment value 454 .

The maximum discharge power determination processing 405 will be described with reference to FIG.

As shown in FIG. 6, the maximum discharge power determination processing 405 is composed of an overload limiter determination table 601 that receives an overload limiter determination value 454 as input and calculates an overload limiter discharge power limit 253 .

Note that the overload limiter determination table 601 may be any table that shows the relationship between the overload limiter determination value and the output ratio. For example, as shown, the horizontal axis is the overload limiter determination value and the vertical axis is the output ratio.

The maximum output calculation function 204 will be described with reference to FIG.

As shown in FIG. 7, the maximum output calculation function 204 uses a comparator 701 to determine whether the voltage 151 of the feeder line is equal to or lower than the second supply start voltage 255. and a function to calculate the product of the rated power 154 and the output result 751 by the multiplier 702 and output it as the output possible power 256 of the first DC power converter 102. be done.

The maximum charge power calculation function 206 will be described with reference to FIG.

The maximum charging power calculation function 206 is configured by a maximum charging power table 801 that determines a maximum charging power 257 based on the charging amount from the charging amount 153, as shown in FIG.

Note that the maximum charge power table 801 may be any table as long as it shows the relationship between the charge amount (SOC) and the maximum charge power. For example, as shown, the horizontal axis is the state of charge (SOC) and the vertical axis is the maximum charging power.

The overload limiter charge power calculation function 207 will be described with reference to FIG.

As shown in FIG. 9, the overload limiter charge power calculation function 207 includes a charge amount data save function 901 that saves the charge amount 153 and outputs a charge amount 951 immediately before this function was performed, and a subtractor 902. A function to calculate the variable charge amount 952 by subtracting the charge amount 951 from the charge amount 153 to the charge amount 153 by the maximum value selector 903. Overload limiter processing 904 for calculating an overload limiter determination value 954 with the variable charge amount 953 on the charging side as input, and overload limiter charging with the overload limiter determination value 954 as input It consists of a maximum charge power determination process 905 based on overload limiter which calculates the power limit 258 .

The overload limiter processing 904 will be described with reference to FIG.

As shown in FIG. 10, the overload limiter process 904 is obtained by multiplying the variable charge amount 953 on the charging side by the charge amount of the power storage device 104 (not shown) and dividing by the operation cycle time of this process. A charging current calculator 1001 that calculates a charging current 1051 per unit time, a function that calculates the square of the charging current 1051 by a multiplier 1002 to calculate a charging current square value 1052, and a subtractor 1003 that calculates the charging current square value 1052. A function of calculating a charging heat load 1054 obtained by subtracting the thermal cooling performance 1053 per unit time of the power storage device 104 from 1055 , the sum of the charging heat loads 1054 in the overload limiter calculation time range 1055 is calculated, and the overload limiter calculation function 1004 outputs the overload limiter judgment value 954 .

The maximum charging power determination processing 905 will be described with reference to FIG. 11 .

As shown in FIG. 11, the maximum charge power determination process 905 is composed of an overload limiter determination table 1101 that receives an overload limiter determination value 954 as an input and calculates an overload limiter charge power limit 258 .

It should be noted that the overload limiter determination table 1101 may be any table that shows the relationship between the overload limiter determination value and the output ratio. For example, as shown, the horizontal axis is the overload limiter determination value and the vertical axis is the output ratio.

Processing of the charge power command calculation function 208 will be described with reference to FIG. 12 .

First, in step 1201, it is determined whether or not the voltage 151 of the feeder line is lower than the regenerative charging start voltage 259. If Yes, proceed to step 1202, and if No, proceed to step 1204.

Next, in step 1202, the value obtained by subtracting the output power 152 of the second DC power converter 103 from the rated power 154 of the first DC power converter 102 is compared with "0", and the larger value is output. do.

Subsequently, in step 1203, the minimum value between the value obtained in step 1202 and the charging power 260 is calculated and output. This is the end.

On the other hand, in step 1204, the minimum value between the output power 152 of the second DC power converter 103 multiplied by (-1) and the charging power 260 is calculated and output. This is the end.

The charge/discharge operation performed in the power storage device 104 as a power transformation system when the processing of the energy control function 105 shown in FIG. It is possible to express from the rated power 154 of the device 102 , the first supply start voltage 251 , the second supply start voltage 255 and the regenerative charging start voltage 259 . This is illustrated in FIGS. 13 and 14. FIG.

13, when the first supply start voltage 251 is V0, the second supply start voltage 255 is V1, the regenerative charging start voltage 259 is Vabs, the rated power 154 is P1, and the charging power 260 is P3, the feeder line It shows that the charge/discharge is determined by the voltage 151 and the output power 152 of .

As described in steps 1202 and 1203 of FIG. 12, when the feeder voltage 151 is lower than the regenerative charging start voltage Vabs, the maximum value between the rated power P1 minus the output power 152 and "0" is first calculated, and then the minimum value with the charging power 260 is output.

This indicates that when the rated power P1 is greater than the output power 152, the difference is compared with the charging power 260, and control is performed so that the smaller power is charged. That is, the operation (2) or (3) in FIG. 13 is performed.

Also, when the rated power P1 is smaller than the output power 152, the charging power is "0", indicating that the operation of the power storage device (power storage device 104) is discharging. That is, the operation (4) in FIG. 13 is performed.

When the voltage 151 of the feeder line is equal to or higher than the regenerative charging start voltage Vabs, as described in step 1204 in FIG. value is calculated as the charging power. That is, the operation (1) in FIG. 13 is performed.

In FIG. 13, regeneration is represented by a negative number, so even in the case of maximum charging, the current is limited to -P3/Vabs.

FIG. 14 shows the case where the first supply start voltage 251 and the second supply start voltage 255 have the same value, the first supply start voltage 251 and the second supply start voltage 255 are set to V0, and the regenerative charge start voltage 259 is set to V0. When Vabs, the rated power 154 is P1, and the charging power 260 is P3, the voltage 151 of the feeder line and the output power 152 determine charging and discharging.

As described in steps 1202 and 1203 of FIG. 12, when the feeder voltage 151 is lower than the regenerative charging start voltage Vabs, the maximum value between the rated power P1 minus the output power 152 and "0" is first calculated, and then the minimum value with the charging power 260 is output.

This indicates that when the rated power P1 is greater than the output power 152, the difference is compared with the charging power 260, and the smaller one is charged. That is, the operation (2) or (3) in FIG. 14 is performed.

Also, when the rated power P1 is smaller than the output power 152, the charging power is "0", indicating that the operation of the power storage device (power storage device 104) is discharging. That is, the operation (4) in FIG. 14 is performed.

When the voltage 151 of the feeder line is equal to or higher than the regenerative charging start voltage Vabs, as described in step 1204 in FIG. value is calculated as the charging power. That is, the operation (1) in FIG. 14 is performed.

In FIG. 14, regeneration is represented by a negative number, so even in the case of maximum charging, the current is limited to -P3/Vabs.

By the processing described above, the charging/discharging operation of the power storage device 104 as a power transformation system is performed, and it becomes possible to secure the necessary large power.

It is desirable that the output performance of the power storage device 104 described in this embodiment is equal to or greater than the difference between the rated output of the second DC power converter 103 and the rated output of the first DC power converter 102 .

As described above, the substation system of this embodiment includes the first AC/DC power converter 101 that converts the AC power from the power system into DC power, and the DC power from the first AC/DC power converter 101. A first DC power conversion device 102 that converts to DC power in the section, a second DC power conversion device 103 that transmits and receives power to and from the feeder, the first DC power conversion device 102 and the second DC power A power storage device that is connected between the converters 103, charges power from the feeder line via the second DC power converter 103, and discharges power to the feeder line via the second DC power converter 103. 104, the first DC power converter 102 is controlled with an output below the rated capacity, and the shortage of power in the second DC power converter 103 is compensated by discharging from the power storage device 104. Control.

Also, when the output of the first DC power conversion device 102 is larger than the load of the second DC power conversion device 103, control is performed so that the power storage device 104 is charged with the difference or less.

Also, when charging the power storage device 104 from the second DC power converter 103, the output of the first DC power converter 102 is stopped.

Also, the charging power is controlled so that the amount of heat generated by the power charging the power storage device 104 is lower than the cooling performance of the power storage device 104 .

Also, the output performance of the power storage device 104 is set to be equal to or greater than the difference between the rated output of the second DC power conversion device 103 and the rated output of the first DC power conversion device 102 .

As a result, the power receiving capacity of the substation is reduced to 2000 kW or less for high-voltage power receiving, and the power receiving infrastructure construction cost is low. It is possible to secure the power performance necessary for the train to run while suppressing it.

A railway power system according to a second embodiment of the present invention will be described with reference to FIGS. 15 and 16. FIG. FIG. 15 is a configuration diagram of the railway power system in this embodiment, solid lines represent the connection relationship between the system and equipment, and dotted lines represent the flow of information from each system and equipment.

As shown in FIG. 15, the railway power system of this embodiment includes a first AC/DC power converter 101 that receives AC power from the power system and converts it to DC power, and A first DC power conversion device 102 that converts DC power into power in the DC section, a second DC power conversion device 103 that converts the power of the first DC power conversion device 102 and outputs it to a feeder line, It is connected between the first DC power conversion device 102 and the second DC power conversion device 103, and charges the power from the feeder via the second DC power conversion device 103, and the second DC power conversion device 103. It has a power storage device 104 that discharges to the feeder line via the power conversion device 103 .

Also, a first substation system having an energy control function 1501, a second AC/DC power conversion device 1502 that receives AC power from the power system and converts it to DC power, and a DC power converter from the second AC/DC power conversion device 1502. It has a second substation system with a first rectifier 1503 that converts power to power in the DC section, and a plurality of trains 1504a, 1504b, 1504c that run on power from feeder lines.

In addition, the energy control function 1501 controls the voltage 151 of the feeder line, the output power 152 of the second DC power converter 103, the charge amount 153 of the power storage device 104, and the rated power of the first DC power converter 102. 154 and no-load voltage information 1551 of the first rectifier 1503, the control command 155 for the second DC power converter 103 and the control command 156 for the first DC power converter 102 are determined. The same reference numerals as in FIG. 1 denote the same configurations as those described in Embodiment 1 (FIG. 1), and detailed description thereof will be omitted.

The energy control function 1501 will be described with reference to FIG. 16 .

The energy control function 1501 includes, as shown in FIG. A maximum discharge power calculation function 1602 that calculates a maximum discharge power 252 based on the voltage 151 of the power storage device 104, the charge amount 153 of the power storage device 104, and the first supply start voltage 1651, and the overload limiter discharge power limit from the charge amount 153. an overload limiter discharge power calculation function 202 that calculates . , the feeder voltage 151, the rated power 154 of the DC power converter 102, and the second supply start voltage 1652, the maximum output calculation function of calculating the output possible power 256 of the first DC power converter 102 1603 and an adder 205 to calculate the sum of the maximum discharge power 254 and the output possible power 256 of the power storage device 104 and calculate the control command 155 for the second DC power conversion device 103 .

Further, a maximum charging power calculation function 206 that calculates a maximum charging power 257 based on the voltage 151 of the feeder line and the charging amount 153 of the power storage device 104 , and an overload limiter charging power limit 258 that calculates an overload limiter charging power limit 258 from the charging amount 153 . Load limiter charge power calculation function 207, feeder voltage 151, output power 152 of DC power converter 103, rated power 154 of DC power converter 102, and regenerative charging start set in energy control function 1501 A charging power command calculation function 208 that calculates a charging power command 261 based on a voltage 259 and a charging power 260, and a minimum value selector 209 select a maximum charging power 257, an overload limiter charging power limit 258, and a charging power command 261. It is composed of a function that calculates the minimum value from among them and sets the control command 156 by multiplying the minimum value by (-1).

The supply start voltage determination function 1601 sets a voltage α lower than the no-load voltage information 1551 as the first supply start voltage 1651, and sets the same value as the first supply start voltage 1651 or a voltage further β lower as the second supply start voltage 1651. This is a function of the supply start voltage 1652 . Any positive values may be set for α and β.

The maximum discharge power calculation function 1602 is the same function as the maximum discharge power calculation function 201, and instead of the first supply start voltage 251 which is one of the inputs of the maximum discharge power calculation function 201, the first supply start voltage I'm just using 1651. Therefore, detailed description is omitted.

Further, the maximum output calculation function 1603 is the same function as the maximum output calculation function 204, and instead of the second supply start voltage 255, which is one of the inputs of the maximum output calculation function 204, a second supply start voltage 1652 is used. is just using Therefore, detailed description is omitted.

With the configuration described above, the charge/discharge operation of the power storage device (power storage device) 104 as the power transformation system described in the first embodiment is performed, and it is possible to secure the necessary large power.

By setting the supply start voltage in consideration of the second substation system configured by the second AC/DC power converter 1502 and the first rectifier 1503, the charge capacity of the power storage device (storage device) can also be reduced. easier to secure.

A railway power system according to a third embodiment of the present invention will be described with reference to FIGS. 17 to 21. FIG. FIG. 17 is a configuration diagram of the railway power system in this embodiment, solid lines represent the connection relationship between the system and equipment, and dotted lines represent the flow of information from each system and equipment.

As shown in FIG. 17, the railway power system of this embodiment includes a first AC/DC power converter 101 that receives AC power from the power system and converts it to DC power, and A first DC power conversion device 102 that converts DC power into power in the DC section, a second DC power conversion device 103 that converts the power of the first DC power conversion device 102 and outputs it to a feeder line, It is connected between the first DC power conversion device 102 and the second DC power conversion device 103, and charges the power from the feeder via the second DC power conversion device 103, and the second DC power conversion device 103. A power storage device 104 that discharges electricity to a feeder line via a power conversion device 103, a first substation system that has an energy control function 1701, and a first substation that receives AC power from the power system and converts it to DC power. 2 AC/DC power converters 1502, a first rectifier 1503 that converts the DC power from the second AC/DC power converters 1502 to power in the DC section, and power from the feeder line. A plurality of trains 1504a, 1504b, 1504c that run based on the above, a diagram management system 1702 that manages diagram information 1751 of the plurality of trains 1504a, 1504b, 1504c, a no-load voltage information 1551 of the first rectifier 1503, and It has a control determination function 1703 that determines a first supply start voltage 1752 , a second supply start voltage 1753 , and a maximum charge power 1754 based on timetable information 1751 .

In addition, the energy control function 1701 includes the voltage 151 of the feeder line, the output power 152 of the second DC power converter 103, the charge amount 153 of the power storage device 104, and the rated power 154 of the first DC power converter 102. And, based on the first supply start voltage 1752, the second supply start voltage 1753, and the maximum charge power 1754, the control command 155 for the second DC power converter 103 and the first DC power converter 102 Determine control directives 156 . The same reference numerals as in FIGS. 1 and 15 denote the same configurations as those described in the first embodiment (FIG. 1) and the second embodiment (FIG. 15), and detailed descriptions thereof are omitted.

The energy control function 1701 will be described with reference to FIG.

As shown in FIG. 18, the energy control function 1701 calculates the maximum discharge power 252 based on the feeder voltage 151, the charge amount 153 of the power storage device 104, and the first supply start voltage 1752. A calculation function 1801, an overload limiter discharge power calculation function 202 that calculates an overload limiter discharge power limit 253 from a charge amount 153, and a minimum value selector 203 select one of the maximum discharge power 252 and the overload limiter discharge power limit 253. Based on the function of setting a small value to the maximum discharge power 254 of the power storage device 104, the voltage 151 of the feeder line, the rated power 154, and the second supply start voltage 1753, the output of the first DC power converter 102 is possible. A maximum output calculation function 1802 that calculates the power 256 and an adder 205 calculate the sum of the maximum discharge power 254 and the output power 256 of the power storage device 104 and calculate the control command 155 for the second DC power conversion device 103. have a function.

Also, a maximum charging power calculation function 206 that calculates a maximum charging power 257 based on the feeder voltage 151 and the charging amount 153, and an overload limiter charging power limit 258 that calculates an overload limiter charging power limit 258 from the charging amount 153. A calculation function 207, a charge upper limit determination unit 1803 that determines a charge upper limit power 1851 based on the charge power 260 and the maximum charge power 1754 set in the energy control function 1701, feeder line voltage 151, and output power 152. , a charging power command calculation function 1804 that calculates a charging power command 261 based on the rated power 154, a regenerative charging start voltage 259 and a charging upper limit power 1851 set in the energy control function 1701, and a minimum value selector 209. calculates the minimum value from among the maximum charging power 257, the overload limiter charging power limit 258, and the charging power command 261, and multiplies the minimum value by (-1) as the control command 156. be.

An example of the timetable information 1751 stored in the timetable management system 1702 will be described with reference to FIG.

The horizontal axis in FIG. 19 represents time, and the vertical axis represents position. Also, in FIG. 19, timetable information for five trains 1901, 1902, 1903, 1904, and 1905 is shown. One-dot chain lines 1901, 1902, and 1903 represent the respective train schedules from E station to A station. Dotted trains 1904 and 1905 represent respective train schedules from A station to E station. This makes it possible to grasp the arrival and departure times of each train at each station and the status of trains at specific times. Since the information shown in FIG. 19 is all that is needed, the information may be in the form of a table showing the arrival and departure times of each station, for example.

The control decision function 1703 will be described with reference to FIG.

A control determination function 1703 includes a charge/discharge control determination function 2001 that determines charge/discharge control information 2051 of the power storage device 104 based on the timetable information 1751 and a charge/discharge control information 2051 and a no-load control of the first rectifier 1503 . It is composed of a supply start voltage determination function 2002 that determines a first supply start voltage 1752 , a second supply start voltage 1753 , and a maximum charge power 1754 based on hourly voltage information 1551 .

The charge/discharge control determination function 2001 will be described with reference to FIG.

FIG. 21 defines the output range of the power storage device 104 and applies it to the diagram information 1751 . In FIG. 21, the area between two lines 2101 and 2102 is the output range of power storage device 104 . At this time, when a train exists in this range, priority is given to discharging, and when there is no train, priority is given to charging.

However, the charging priority range is determined in consideration of the overload limiter time range. For example, if charging is prioritized until just before the train 1901 enters the output range of the power storage device 104, and discharging is prioritized immediately after the train 1901 enters the output range of the power storage device 104, discharging takes place considering the overload limiter time range. may not be broken.

For this reason, charging is prioritized by subtracting the overload limiter time range from the time at which the train 1901 enters the output range of the power storage device 104 .

In the area sandwiched between two lines 2101 and 2102 in FIG. 21, the dashed arrow indicates charging priority, and the solid arrow indicates discharging priority. In addition, time periods without arrows in the area indicate that no trains are on the line in the area, but charging is not prioritized in consideration of the overload limiter time range. It should be noted that this area may be set to a state in which priority is not given to charging, for example, a state in which priority is given to discharging or no charging/discharging.

By doing so, it is possible to perform control so as to secure the amount of charge when priority is given to charging, and it is possible to perform control so as to secure the required high power when priority is given to discharge. becomes.

The supply start voltage determination function 2002 sets the first supply start voltage 1752 and the second supply start voltage 1753 to "0" when the charge/discharge control information 2051 indicates charging. Maximum charge power 1754 is the maximum charge power of power storage device 104 .

Further, when the charge/discharge control information 2051 is other than charging, a voltage α lower than the no-load voltage information 1551 is set as the first supply start voltage 1752, and the same value as the first supply start voltage 1752 or further A second supply start voltage 1753 is a voltage lower than β. Any positive values may be set for α and β. Maximum charge power 1754 is set to "0".

Charge upper limit determination unit 1803 shown in FIG. 18 will be described. When the maximum charge power 1754 is "0", the charge power 260 is set to the charge upper limit power 1851, and when the maximum charge power 1754 is other than "0", the maximum charge power 1754 is set to the charge upper limit power 1851. By this process, when the charge/discharge control information 2051 is discharging, the same charge control as in the first and second embodiments is performed, and when the charge/discharge control information 2051 is other than discharging, the charging power is increased and the charging is performed. Efforts can be made to secure sufficient quantities.

With these functions, the charge/discharge operation of the power storage device (power storage device 104) as a power transformation system is performed while the charge amount of the power storage device 104 is secured, making it possible to secure the necessary large amount of power.

In this embodiment, the description is based on the operation diagram, but this diagram is not limited to a predetermined one, but reflects the situation that changes from moment to moment such as information on trains running on the route. It can be anything.

Embodiment 4 A railway power system according to Embodiment 4 of the present invention will be described with reference to FIGS. 22 to 24 . FIG. 22 is a configuration diagram of the railway power system in this embodiment, solid lines represent the connection relationship between the system and equipment, and dotted lines represent the flow of information from each system and equipment.

As shown in FIG. 22, the railway power system of this embodiment includes a first AC/DC power converter 101 that receives AC power from the power system and converts it to DC power, and A first DC power conversion device 102 that converts DC power into power in the DC section, a second DC power conversion device 103 that converts the power of the first DC power conversion device 102 and outputs it to a feeder line, It is connected between the first DC power conversion device 102 and the second DC power conversion device 103, and charges the power from the feeder via the second DC power conversion device 103, and the second DC power conversion device 103. A power storage device 104 that discharges electricity to a feeder line via a power conversion device 103, a first substation system that has an energy control function 2201, and a first substation that receives AC power from the power system and converts it to DC power. 2 AC/DC power converters 1502, a second transformer system having a first rectifier 1503 that converts the DC power from the second AC/DC power converters 1502 to power in the DC section, and power from the feeder line. based on a plurality of trains 1504a, 1504b, 1504c running based on the position and power information 2251a, 2251b, 2251c of the plurality of trains 1504a, 1504b, 1504c, and no-load voltage information 1551 of the first rectifier 1503. has a control determination function 2202 that determines a first supply start voltage 2252 , a second supply start voltage 2253 and a maximum charge power 2254 .

In addition, the energy control function 2201 includes the voltage 151 of the feeder line, the output power 152 of the second DC power converter 103, the charge amount 153 of the power storage device 104, and the rated power 154 of the first DC power converter 102. And, based on the first supply start voltage 2252, the second supply start voltage 2253, and the maximum charging power 2254, the control command 155 for the second DC power converter 103 and the first DC power converter 102 Determine control directives 156 . The same reference numerals as in FIGS. 1 and 15 denote the same configurations as those described in the first embodiment (FIG. 1) and the second embodiment (FIG. 15), and detailed description thereof is omitted.

The energy control function 2201 will be described with reference to FIG.

As shown in FIG. 23, the energy control function 2201 calculates the maximum discharge power 252 based on the feeder voltage 151, the charge amount 153 of the power storage device 104, and the first supply start voltage 2252. Calculation function 2301 , overload limiter discharge power calculation function 202 for calculating overload limiter discharge power limit 253 from charge amount 153 , minimum value selector 203 , maximum discharge power 252 and overload limiter discharge power limit 253 Based on the function of setting a small value to the maximum discharge power 254 of the power storage device 104, the voltage 151 of the feeder line, the rated power 154, and the second supply start voltage 2253, the output of the first DC power converter 102 is possible. A maximum output calculation function 2302 that calculates the power 256 and an adder 205 calculate the sum of the maximum discharge power 254 of the power storage device 104 and the output possible power 256, and calculate the control command 155 of the second DC power converter 103. have a function.

Also, a maximum charging power calculation function 206 that calculates a maximum charging power 257 based on the feeder voltage 151 and the charging amount 153, and an overload limiter charging power limit 258 that calculates an overload limiter charging power limit 258 from the charging amount 153. A calculation function 207, a charge upper limit determination unit 2303 that determines a charge upper limit power 1851 based on the charge power 260 and the maximum charge power 2254 set in the energy control function 2201, feeder line voltage 151, and output power 152. , a charging power command calculation function 1804 that calculates a charging power command 261 based on the rated power 154, a regenerative charging start voltage 259 and a charging upper limit power 1851 set in the energy control function 2201, and a minimum value selector 209. calculates the minimum value from among the maximum charging power 257, the overload limiter charging power limit 258, and the charging power command 261, and multiplies the minimum value by (-1) as the control command 156. be.

The maximum discharge power calculation function 2301 is the same function as the maximum discharge power calculation function 1801 in FIG. Only the starting supply voltage 2252 is used. Therefore, detailed description is omitted.

Further, the maximum output calculation function 2302 is the same function as the maximum output calculation function 1802, and instead of the second supply start voltage 1753 which is one of the inputs of the maximum output calculation function 1802, the second supply start voltage 2253 is used. is just using Therefore, detailed description is omitted.

Also, the charge upper limit determination unit 2303 has the same function as the charge upper limit determination unit 1803, and only uses the maximum charge power 2254 instead of the maximum charge power 1754 which is one of the inputs of the charge upper limit determination unit 1803. is. Therefore, detailed description is omitted.

The control decision function 2202 will be described with reference to FIG.

First, in step 2401, a voltage α lower than the no-load voltage information 1551 is set as the first supply start voltage 2252, and the same value as the first supply start voltage 2252 or a voltage lower by β is set as the second supply start voltage. Let the voltage be 2253 . Any positive values may be set for α and β.

Next, in step 2402, among the trains 1504a, 1504b, and 1504c on the line, the vehicle X closest to the substation is extracted from among the vehicles performing regeneration, and the distance L from that vehicle X is calculated. Ask. If there is no regenerative vehicle, L=∞.

Subsequently, at step 2403, the light load regeneration start voltage Va of the regeneration vehicle extracted at step 2402 is extracted.

The light load regeneration starting voltage Va of the regenerative vehicle is extracted based on the characteristic information of each train (not shown). The characteristic information of each train only needs to include the light load regeneration start voltage Va. Good luck. Va=0 when there is no regenerative vehicle.

Subsequently, in step 2404, the distance L extracted in step 2402, the light load regeneration start voltage Va extracted in step 2403, the regeneration charge start voltage Vabs of the power storage device 104, and the feeding resistance per unit distance (not shown) Based on R, the maximum charging current Imax is calculated by the following formula (1).

Imax = (Va - Vabs)/(R x L) (1)
Subsequently, at step 2405 , the chargeable power is calculated by multiplying the regenerative charging start voltage Vabs of the power storage device 104 by the Imax calculated at step 2404 , and is set as the maximum charging power 2254 .

The processing ends here. By doing so, only the portion of the regenerative vehicle that has a light load is set as the maximum charging power, and as a result, it is possible to avoid unnecessary charging.

With the configuration described above, the charge/discharge operation of the power storage device (power storage device) 104 as the power transformation system is performed as described in the first embodiment, and it is possible to secure the necessary large power.

In addition, the present invention is not limited to the above-described embodiments, and includes various modifications. For example, the above embodiments have been described in detail to aid understanding of the present invention, and are not necessarily limited to those having all the described configurations. In addition, it is possible to replace part of the configuration of one embodiment with the configuration of another embodiment, and it is also possible to add the configuration of another embodiment to the configuration of one embodiment. Moreover, it is possible to add, delete, or replace a part of the configuration of each embodiment with another configuration.

For example, the present invention may be implemented by combining the control determination function 1703 of the third embodiment and the control determination function 2202 of the fourth embodiment and inputting necessary timetable information and vehicle information.

DESCRIPTION OF SYMBOLS 101... 1st AC/DC power converter 102... 1st DC power converter 103... 2nd DC power converter 104... Power storage device (electricity storage device)
105 Energy control function 151 Feeder voltage 152 Output power (of DC power converter 103) 153 Charge amount (of power storage device 104) 154 Rated power (of DC power converter 102) 155 (DC Power conversion device 103) control command 156... (DC power conversion device 102) control command 201... Maximum discharge power calculation function 202... Overload limiter discharge power calculation function 203... Minimum value selector 204... Maximum output calculation function 205... Adder 206 Maximum charge power calculation function 207 Overload limiter charge power calculation function 208 Charge power command calculation function 209 Minimum value selector 251 First supply start voltage 252 Maximum discharge (of power storage device 104) Power 253 Overload limiter discharge power limit 254 Maximum discharge power (of power storage device 104) 255 Second supply start voltage 256 Output possible power (of DC power conversion device 102) 257 Maximum charge power 258 Overload Load limiter charge power limit 259 Regenerative charge start voltage 260 Charge power 261 Charge power command 301 Maximum discharge power table 302 Comparator 303 Multiplier 351 Maximum discharge power 352 Output result 401 Charge amount data storage function 402 ... Subtractor 403 ... Maximum value selector 404 ... Overload limiter processing 405 ... Maximum discharge power determination processing 451 ... Charge amount (one time before) 452 ... Fluctuation charge amount 453 ... Fluctuation charge amount 454 ... Overload limiter judgment value 501... Discharge current calculator 502... Multiplier 503... Subtractor 504... Overload limiter calculation function 551... Discharge current 552... Discharge current squared value 553... Thermal cooling performance 554... Discharge heat load 555... Overload limiter calculation time range 601 Overload limiter determination table 701 Comparator 702 Multiplier 751 Output result 801 Maximum charge power table 901 Charge amount data storage function 902 Subtractor 903 Maximum value selector 904 Overload limiter processing 905 Maximum Charging power determination process 951 Charge amount (one time before) 952 Fluctuation charge amount 953 Fluctuation charge amount 954 Overload limiter determination value 1001 Charge current calculator 1002 Multiplier 1003 Subtractor 1004 Overload limiter Calculation function 1051 Charging current 1052 Charging current squared value 1053 Thermal cooling performance 1054 Charging heat load 1055 Overload limiter calculation time range 1101 Overload Limiter determination table 1501 Energy control function 1502 Second AC/DC power converter 1503 First rectifier 1504a, 1504b, 1504c Train 1551 No-load voltage information 1601 Supply start voltage determination function 1602 Maximum discharge power Calculation function 1603 Maximum output calculation function 1651 First supply start voltage 1652 Second supply start voltage 1701 Energy control function 1702 Diagram management system 1703 Control determination function 1751 Diagram information 1752 First supply start Voltage 1753 Second supply start voltage 1754 Maximum charge power 1801 Maximum discharge power calculation function 1802 Maximum output calculation function 1803 Charge upper limit determination unit 1804 Charge power command calculation function 1851 Charge upper limit power 1901, 1902, 1903 , 1904, 1905... Train 2001... Charge/discharge control decision function 2002... Supply start voltage decision function 2051... Charge/discharge control information 2101, 2102... Output range of power storage device (storage device) 2201... Energy control function 2202... Control decision function 2251a, 2251b, 2251c (train) position and power information 2252 First supply start voltage 2253 Second supply start voltage 2254 Maximum charge power 2301 Maximum discharge power calculation function 2302 Maximum output calculation function 2303 Charge upper limit determination unit

Claims (13)

a first AC/DC power converter that converts AC power from a power system into DC power;
a first DC power converter that converts DC power from the first AC/DC power converter into DC power in a DC section;
a second DC power converter that transmits and receives power to and from a feeder;
Connected between the first DC power converter and the second DC power converter, charging power from the feeder line via the second DC power converter, and charging the second DC power converter a power storage device that discharges to the feeder line via a DC power converter,
The first DC power conversion device is controlled with an output below the rated capacity, and the power shortage in the second DC power conversion device is controlled so as to be compensated for by discharging from the power storage device. substation system. In the substation system according to claim 1,
A substation system characterized in that, when the output of the first DC power conversion device is greater than the load of the second DC power conversion device, the power storage device is controlled to be charged at a difference equal to or less than the difference. In the substation system according to claim 1 or 2,
A power transformation system, wherein an output of the first DC power converter is stopped when charging the power storage device from the second DC power converter. In the substation system according to any one of claims 1 to 3,
A power transformation system, wherein charging power is controlled such that the amount of heat generated by the power charged in the power storage device is lower than the cooling performance of the power storage device. In the substation system according to any one of claims 1 to 4,
The power transformation system, wherein the output performance of the power storage device is equal to or greater than the difference between the rated output of the second DC power converter and the rated output of the first DC power converter. In an electric railway system using the substation system according to any one of claims 1 to 5,
a second AC/DC power converter that converts AC power from a power system into DC power;
A power transformation system different from the power transformation system having a first rectifier that converts the DC power from the second AC/DC power converter and outputs it to a feeder line,
An electric railway system, wherein control is performed such that a voltage at which the substation system operates is lower than a voltage at which the other substation system operates. In the electric railway system according to claim 6,
Equipped with a timetable management system having operation information of one or more trains,
An electric railway system, wherein control of the substation system is determined based on the operation information. In the electric railway system according to claim 6 or 7,
Equipped with a property management system having property information of one or more trains,
An electric railway system, wherein control of the substation system is determined based on the position, electric power and characteristic information of the one or more trains. A control method for a substation system using both a substation and a power storage device,
AC power from a substation is converted to DC power by an AC/DC power converter,
DC power from the AC/DC power converter is converted into DC power in the DC section by the first DC power converter, and the output of the first DC power converter is controlled below the rated capacity,
Converting the DC power from the first DC power converter into DC power to be transmitted to the feeder line by the second DC power converter,
A control method for a substation system, characterized in that control is performed such that a shortage of electric power in the second DC power conversion device is compensated for by discharging from a power storage device. A control method for a substation system according to claim 9,
When the output of the first DC power conversion device is greater than the load of the second DC power conversion device, the power storage device is controlled to be charged by the difference or less. control method. A control method for a substation system according to claim 9 or 10,
A control method for a substation system, comprising stopping an output of the first DC power converter when charging the power storage device from the second DC power converter. A control method for a substation system according to any one of claims 9 to 11,
A control method for a substation system, comprising: controlling charging power such that the amount of heat generated by the power charged in the power storage device is lower than the cooling performance of the power storage device. A control method for a substation system according to any one of claims 9 to 12,
A control method for a substation system, wherein the output performance of the power storage device is equal to or greater than a difference between the rated output of the second DC power converter and the rated output of the first DC power converter.

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