JP7357018B2 - Substation system and control method of substation system, electric railway system - Google Patents

Description

The present invention relates to the configuration of a substation system and its control, and particularly relates to a technology that is effective when applied to a railway power system for operating railway vehicles.

In order to construct a railway system in an urban area with a large number of trains, large-capacity substation equipment is required. Generally, substations with a receiving capacity of 6,000 kW or more require special high-voltage power receiving infrastructure from the power transmission system, such as steel towers or buried piping, which requires a large amount of cost.
Furthermore, from the viewpoint of suppressing rail-to-ground potential, it is important to reduce the distance between substations. However, in cities in emerging countries, it is extremely difficult to construct a power feeding system due to the cost and capacity of the power receiving infrastructure.

In addition, considering local routes with low power receiving infrastructure capacity, if large amounts of power are required, it is necessary to construct a power grid by transmitting power from special high voltage power receiving substations using power transmission lines. Maintenance of power transmission lines requires a large amount of cost.

Under these circumstances, it is important to install substations and make it possible to supply power by receiving power from power distribution systems such as utility poles, where the cost of constructing power receiving infrastructure is low, by keeping substations at a high voltage of 2,000 kW or less. That's true.

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

Japanese Patent Application Publication No. 2010-58565

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

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

For this reason, when regenerative power is charged as much as possible within a certain continuous time range, discharging within that continuous time range is limited. As a result, the power required to be assisted by the power storage device cannot be obtained, and as a result, the output from the substation decreases, potentially affecting operation.

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

In order to solve the above problems, the present invention includes a first AC/DC power converter that converts AC power from a power system into DC power, and a DC power converter that converts the DC power from the first AC/DC power converter into DC power. A first DC power converter that converts to DC power, a second DC power converter that transmits and receives power to and from a feeder line, and between the first DC power converter and the second DC power converter. an electric power storage connected to the feeder, which charges the power from the feeder line via the second DC power converter, and discharges electricity to the feeder line via the second DC power converter; a device, the first DC power converter is controlled to have an output below its rated capacity, and the power shortage in the second DC power converter is compensated for by discharging from the power storage device. It is characterized by control.

Further, the present invention provides an electric railway system using the above-mentioned substation system, including: a second AC/DC power converter that converts AC power from the power system into DC power; a first rectifier that converts electric power and outputs it to a feeder line; further comprising another substation system different from the substation system, the voltage at which the substation system operates is the same as the voltage at which the another substation system operates. The feature is that the voltage is controlled to be lower than the voltage.

The present invention also provides a method for controlling a substation system that uses a substation and a power storage device, in which AC power from the substation is converted to DC power by an AC/DC power converter, and the AC power from the AC/DC power converter is Converting the DC power to DC power in the DC section by a first DC power converter, controlling the output of the first DC power converter to be below the rated capacity, and controlling the output of the first DC power converter to control to convert the DC power into DC power transmitted to the feeder line by a second DC power converter, and compensate for the lack of power in the second DC power converter by discharging from the power storage device. It is 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 power performance necessary for running trains while suppressing power received from the power system 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 made clear by the following description of the embodiments.

1 is a diagram showing a schematic configuration of a substation system according to Example 1 of the present invention. 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 the configuration of an overload limiter discharge power calculation function 202 in FIG. 2. FIG. 5 is a diagram showing a 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 charging power calculation function 206 in FIG. 2. FIG. 3 is a diagram showing the 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 in FIG. 9. 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 charging power command calculation function 208 in FIG. 2. FIG. 2 is a diagram showing an example of charging/discharging control of the power storage device 104 of FIG. 1. FIG. 2 is a diagram showing an example of charging/discharging control of the power storage device 104 of FIG. 1. FIG. FIG. 2 is a diagram showing a schematic configuration of a railway power system according to a second embodiment of the present invention. 16 is a diagram showing the configuration of an energy control function 1501 in FIG. 15. FIG. It is a figure showing the schematic structure of the railway electric power system concerning Example 3 of the present invention. 18 is a diagram showing the configuration of an energy control function 1701 in FIG. 17. FIG. It is a figure which shows the example of the bus schedule based on Example 3 of this invention. 18 is a diagram showing the configuration of a control determination function 1703 in FIG. 17. FIG. It is a figure which shows the charging/discharging control method based on Example 3 of this invention. It is a figure showing the schematic structure of the railway electric power system concerning Example 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 the control determination function 2202 in FIG. 22. FIG.

Embodiments of the present invention will be described below with reference to the drawings. Note that in each drawing, the same components are denoted by the same reference numerals, and detailed explanations of overlapping parts will be omitted.

EMBODIMENT OF THE INVENTION With reference to FIGS. 1-14, the substation system and its control method based on Example 1 of this invention are demonstrated. FIG. 1 is a configuration diagram of the substation system in this embodiment, where 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. 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 into DC power, and a DC power converter 101 that receives AC power from a power system and converts it into DC power. A first DC power converter 102 that converts power into power in a DC section, a second DC power converter 103 that converts the power of the first DC power converter 102 and outputs it to the feeder line, It is connected between the first DC power converter 102 and the second DC power converter 103, and charges the power from the feeder line via the second DC power converter 103, and also charges the second DC power It has a power storage device 104 that discharges electricity to a feeder line via a conversion device 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, 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 explained using FIG. 2.

As shown in FIG. 2, the energy control function 105 determines the maximum discharge power 252 based on the voltage 151 of the feeder line, the amount of charge 153, and the first supply start voltage 251 set in the energy control function 105. The maximum discharge power calculation function 201 calculates the overload limiter discharge power limit 253 from the charge amount 153, the overload limiter discharge power calculation function 202 calculates the overload limiter discharge power limit 253 from the charge amount 153, and the minimum value selector 203. A function that sets the smaller value of the discharge power limit 253 as the maximum discharge power 254 of the power storage device 104, a voltage 151 of the feeder line, a rated power 154, and a second supply start set in the energy control function 105. A maximum output calculation function 204 calculates the outputtable power 256 of the first DC power converter 102 based on the voltage 255, and an adder 205 calculates the maximum discharge power 254 of the power storage device 104 and the first DC power converter It has a function of calculating the sum of the 102 outputtable electric powers 256 and calculating it as the control command 155 of the second DC power converter 103.

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

Here, the first supply start voltage 251 is a threshold voltage that determines discharging from the power storage device 104, and the second supply start voltage 255 is a threshold voltage that determines supply from the first DC power converter 102. . Further, it is desirable that the first supply start voltage 251≦the second supply start voltage 255 holds true.

The maximum discharge power calculation function 201 will be explained using FIG. 3.

As shown in FIG. 3, the maximum discharge power calculation function 201 uses a maximum discharge power table 301 that determines the maximum discharge power 351 based on the charge amount from the charge amount 153 and a comparator 302 to calculate the voltage 151 of the feeder line. A function that determines whether or not the first supply start voltage 251 is lower than the first supply start voltage 251 and outputs "1" in the case of Yes and "0" in the case of No as the output result 352, and the multiplier 303 outputs the maximum discharge power 351. It is configured with a function of calculating the product of the results 352 and outputting 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 that allows the relationship between the amount of charge (SOC: State of Charge) and the maximum discharge power to be understood. For example, as shown in the figure, a graph is constructed in which the horizontal axis represents the amount of charge (SOC) and the vertical axis represents the maximum discharge power.

The overload limiter discharge power calculation function 202 will be explained using FIG. 4.

As shown in FIG. 4, the overload limiter discharge power calculation function 202 includes a charge amount data storage function 401 that stores the charge amount 153 and outputs the charge amount 451 of the previous time when this function was executed, and a subtractor 402. The function calculates the variable charge amount 452 by subtracting the charge amount 153 from the previous charge amount 451, and the maximum value selector 403 selects the larger of the variable charge amount 452 and the "0" value on the discharging side. A function to output a variable charge amount 453, an overload limiter process 404 that calculates an overload limiter judgment value 454 using the variable charge amount 453 as input on the discharging side, and an overload limiter discharge using the overload limiter judgment value 454 as input. It is configured by a maximum discharge power determination process 405 based on an overload limiter that calculates a power limit 253.

The overload limiter processing 404 will be explained using FIG. 5.

As shown in FIG. 5, the overload limiter process 404 is obtained by multiplying the variable charge amount 453 on the discharging 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 calculation unit 501 that calculates a discharge current 551 per unit time, a multiplier 502 that calculates the square of the discharge current 551, and a function that calculates a discharge current square value 552, and a subtracter 503 that calculates the discharge current square value 552. A function to calculate the discharge heat load 554 obtained by subtracting the thermal cooling performance 553 per unit time of the power storage device 104 from 555, the overload limiter calculation function 504 calculates the sum of the discharge heat loads 554 in the overload limiter calculation time range 555 and outputs it as the overload limiter judgment value 454.

The maximum discharge power determination process 405 will be explained using FIG. 6.

As shown in FIG. 6, the maximum discharge power determination process 405 includes an overload limiter determination table 601 that calculates the overload limiter discharge power limit 253 by inputting the overload limiter determination value 454.

Note that the overload limiter determination table 601 may be any table that allows the relationship between the overload limiter determination value and the output ratio to be understood. For example, as shown in the figure, a graph is constructed in which the horizontal axis represents the overload limiter judgment value and the vertical axis represents the output ratio.

The maximum output calculation function 204 will be explained using FIG. 7.

As shown in FIG. 7, the maximum output calculation function 204 uses a comparator 701 to determine whether the voltage 151 of the feeder wire is equal to or lower than the second supply start voltage 255, and returns "1" if Yes, and "1" if No. The multiplier 702 calculates the product of the rated power 154 and the output result 751 and outputs it as the outputtable power 256 of the first DC power converter 102. be done.

The maximum charging power calculation function 206 will be explained using FIG. 8.

The maximum charging power calculation function 206 is configured with 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 charging power table 801 may be any table that allows the relationship between the amount of charge (SOC) and the maximum charging power to be understood. For example, as shown in the figure, the graph is configured such that the horizontal axis represents the amount of charge (SOC) and the vertical axis represents the maximum charging power.

The overload limiter charging power calculation function 207 will be explained using FIG. 9.

As shown in FIG. 9, the overload limiter charge power calculation function 207 includes a charge amount data storage function 901 that stores the charge amount 153 and outputs the charge amount 951 of the previous time when this function was executed, and a subtracter 902. The function calculates the variable charge amount 952 by subtracting the previous charge amount 951 from the charge amount 153, and the maximum value selector 903 selects the larger of the variable charge amount 952 and the "0" value on the charging side. Overload limiter processing 904 that calculates an overload limiter judgment value 954 using the variable charge amount 953 as input on the charging side, and overload limiter charging using the overload limiter judgment value 954 as input. It is configured by a maximum charging power determination process 905 based on an overload limiter that calculates a power limit 258.

The overload limiter processing 904 will be explained using FIG. 10.

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 calculation unit 1001 that calculates a charging current 1051 per unit time, a multiplier 1002 that calculates the square of the charging current 1051, and a function that calculates a charging current squared value 1052, and a subtracter 1003 that calculates the charging current squared value 1052. A function to calculate the charging thermal load 1054 obtained by subtracting the thermal cooling performance 1053 per unit time of the power storage device 104 from 1055, the overload limiter calculation function 1004 calculates the sum of the charging thermal loads 1054 in the overload limiter calculation time range 1055 and outputs it as an overload limiter judgment value 954.

The maximum charging power determination process 905 will be explained using FIG. 11.

As shown in FIG. 11, the maximum charging power determination process 905 includes an overload limiter determination table 1101 that calculates an overload limiter charging power limit 258 by inputting an overload limiter determination value 954.

Note that the overload limiter determination table 1101 may be any table that allows the relationship between the overload limiter determination value and the output ratio to be understood. For example, as shown in the figure, a graph is constructed in which the horizontal axis represents the overload limiter judgment value and the vertical axis represents the output ratio.

The processing of the charging power command calculation function 208 will be explained using FIG. 12.

First, in step 1201, it is determined whether the voltage 151 of the feeder line is lower than the regenerative charging start voltage 259. If Yes, the process proceeds to step 1202, and if No, the process proceeds 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 concludes the process.

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 concludes the process.

When the process of the energy control function 105 shown in FIG. It can be expressed 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 shown in FIGS. 13 and 14.

FIG. 13 shows how the feeder line This shows that charging and discharging are determined by the voltage 151 and output power 152.

As explained 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 respect to charging power 260 is output.

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

Further, when the rated power P1 is smaller than the output power 152, the charging power becomes "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.

In addition, when the voltage 151 of the feeder line is higher than the regenerative charging start voltage Vabs, as explained in step 1204 of FIG. Calculate the value as charging power. That is, the operation (1) in FIG. 13 is performed.

In addition, in FIG. 13, since regeneration is expressed as a negative value, even in the case of maximum charging, the current is limited by -P3/Vabs.

FIG. 14 shows a case where the first supply start voltage 251 and the second supply start voltage 255 are the same value, the first supply start voltage 251 and the second supply start voltage 255 are set to V0, and the regenerative charging start voltage 259 is set to V0. Vabs, when the rated power 154 is P1 and the charging power 260 is P3, it is shown that charging and discharging are determined by the voltage 151 of the feeder line and the output power 152.

As explained 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 respect to charging power 260 is output.

This indicates that when the rated power P1 is larger 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.

Further, when the rated power P1 is smaller than the output power 152, the charging power becomes "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.

In addition, when the voltage 151 of the feeder line is higher than the regenerative charging start voltage Vabs, as explained in step 1204 of FIG. Calculate the value as charging power. That is, the operation (1) in FIG. 14 is performed.

In addition, in FIG. 14, since regeneration is expressed as a negative value, even in the case of maximum charging, the current is limited by -P3/Vabs.

Through the processing described above, the power storage device 104 as a substation system is charged and discharged, and it becomes possible to secure the necessary large amount of power.

Note that the output performance of the power storage device 104 described in this embodiment is desirably greater than or equal to 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 explained above, the substation system of this embodiment includes the first AC/DC power converter 101 that converts AC power from the power system into DC power, and the DC power converter 101 that converts the DC power from the first AC/DC power converter 101 into DC power. A first DC power converter 102 that converts the power into DC power at the feeder, a second DC power converter 103 that transmits and receives power between the feeder line, and a second DC power converter 102 that converts the first DC power converter 102 to DC power. A power storage device that is connected between the converters 103 and 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 power shortage in the second DC power converter 103 is compensated for by discharging from the power storage device 104. Control.

Further, when the output of the first DC power converter 102 is larger than the load of the second DC power converter 103, the power storage device 104 is controlled to be charged at a level equal to or less than the difference.

Further, 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.

Further, 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.

Further, the output performance of the power storage device 104 is set to be greater than or equal to 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 a result, by reducing the receiving capacity of substations by keeping the high-voltage power receiving to 2000 kW or less, it is possible to install substations that receive power from distribution systems such as utility poles, which are inexpensive to construct power receiving infrastructure, and to reduce the power received from the grid to below the rated capacity. It is possible to secure the electric power performance necessary for the train to run while reducing the power consumption.

A railway power system according to a second embodiment of the present invention will be described with reference to FIGS. 15 and 16. FIG. 15 is a configuration diagram of the railway power system in this embodiment, where solid lines represent the connection relationships between the systems 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 a power system and converts it into DC power, and a a first DC power converter 102 that converts DC power to power in a DC section; a second DC power converter 103 that converts the power of the first DC power converter 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 the power from the feeder line via the second DC power converter 103, and also charges the power from the feeder line. It has a power storage device 104 that discharges electricity to a feeder line via a power conversion device 103.

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

The energy control function 1501 also 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 the no-load voltage information 1551 of the first rectifier 1503, a control command 155 for the second DC power converter 103 and a control command 156 for the first DC power converter 102 are determined. Components that are the same as those described in Example 1 (FIG. 1) are designated by the same reference numerals as in FIG. 1, and detailed description thereof will be omitted.

The energy control function 1501 will be explained using FIG. 16.

As shown in FIG. 16, the energy control function 1501 includes a supply start voltage determination function 1601 that determines a first supply start voltage 1651 and a second supply start voltage 1652 based on no-load voltage information 1551, and a feeder line A maximum discharge power calculation function 1602 that calculates the 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 an overload limiter discharge power limit from the charge amount 153. An overload limiter discharge power calculation function 202 that calculates 253 and a minimum value selector 203 that sets the smaller value of the maximum discharge power 252 and the overload limiter discharge power limit 253 as the maximum discharge power 254 of the power storage device 104. , a maximum output calculation function that calculates the possible output power 256 of the first DC power converter 102 based on the feeder voltage 151, the rated power 154 of the DC power converter 102, and the second supply start voltage 1652. 1603 and an adder 205 to calculate the sum of the maximum discharge power 254 and the outputtable power 256 of the power storage device 104, and calculate this as a control command 155 for the second DC power converter 103.

Additionally, there is a maximum charging power calculation function 206 that calculates the 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 the charging power limit 258 from the charging amount 153. Load limiter charging 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 The charging power command calculation function 208 calculates the charging power command 261 based on the voltage 259 and the charging power 260, and the minimum value selector 209 calculates the maximum charging power 257, the overload limiter charging power limit 258, and the charging power command 261. It is configured by a function of calculating the minimum value from among them and multiplying the minimum value by (-1) as the control command 156.

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 function is to set the supply start voltage 1652. These α and β may be set to arbitrary positive values.

The maximum discharge power calculation function 1602 is the same function as the maximum discharge power calculation function 201, and uses the first supply start voltage instead of the first supply start voltage 251, which is one of the inputs of the maximum discharge power calculation function 201. 1651 is only used. Therefore, detailed explanation will be 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. It's just using . Therefore, detailed explanation will be omitted.

With the configuration described above, charging and discharging operations of the power storage device (power storage device) 104 as a power substation system as described in the first embodiment are performed, and it becomes possible to secure the necessary large amount of power.

Note that 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 charging capacity of the power storage device (power storage device) can also be increased. 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. 17 is a configuration diagram of the railway power system in this embodiment, where solid lines represent the connection relationships between the systems 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 a power system and converts it into DC power, and a a first DC power converter 102 that converts DC power to power in a DC section; a second DC power converter 103 that converts the power of the first DC power converter 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 the power from the feeder line via the second DC power converter 103, and also charges the power from the feeder line. 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 system that receives AC power from the power system and converts it into DC power. A second power substation system having a second AC/DC power converter 1502, a first rectifier 1503 that converts DC power from the second AC/DC power converter 1502 into power in a DC section, and power from a feeder line. a plurality of trains 1504a, 1504b, 1504c that run based on a timetable management system 1702 that manages timetable information 1751 of the plurality of trains 1504a, 1504b, 1504c; no-load voltage information 1551 of the first rectifier 1503; It has a control determination function 1703 that determines a first supply start voltage 1752, a second supply start voltage 1753, and a maximum charging power 1754 based on timetable information 1751.

The energy control function 1701 also 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 154 of the first DC power converter 102. Based on the first supply start voltage 1752, the second supply start voltage 1753, and the maximum charging power 1754, the control command 155 of the second DC power converter 103 and the first DC power converter 102 are determined. A control command 156 is determined. The same configurations as those described in Example 1 (FIG. 1) and Example 2 (FIG. 15) are designated by the same reference numbers as in FIGS. 1 and 15, and detailed description thereof will be omitted.

The energy control function 1701 will be explained using FIG. 18.

As shown in FIG. 18, the energy control function 1701 calculates the maximum discharge power 252 based on the voltage 151 of the feeder line, the amount of charge 153 of the power storage device 104, and the first supply start voltage 1752. The calculation function 1801, the overload limiter discharge power calculation function 202 that calculates the overload limiter discharge power limit 253 from the charge amount 153, and the minimum value selector 203 select between the maximum discharge power 252 and the overload limiter discharge power limit 253. The output of the first DC power converter 102 is possible based on the function of setting a small value as 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. A maximum output calculation function 1802 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 outputtable power 256, and calculate it as the control command 155 for the second DC power converter 103. Has a function.

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

An example of the timetable information 1751 included in the timetable management system 1702 will be explained using FIG. 19.

In FIG. 19, the horizontal axis represents time and the vertical axis represents position. Further, in FIG. 19, timetable information for five trains, 1901, 1902, 1903, 1904, and 1905, is shown. The dashed-dotted lines 1901, 1902, and 1903 represent the train schedules for trains heading from E station to A station. Dotted line trains 1904 and 1905 represent the respective train schedules heading from A station to E station. This makes it possible to know the arrival and departure times of each train at each station and the status of the train at a particular time. Note that since it is sufficient to have the information shown in FIG. 19, it may be in the form of, for example, a table showing the departure and arrival times at each station.

The control determination function 1703 will be explained using FIG. 20.

The control determining function 1703 includes a charging/discharging control determining function 2001 that determines charging/discharging control information 2051 of the power storage device 104 for each time based on timetable information 1751, and a charging/discharging control information 2051 and no-load control of the first rectifier 1503. The supply start voltage determination function 2002 determines a first supply start voltage 1752 , a second supply start voltage 1753 , and a maximum charging power 1754 based on current voltage information 1551 .

The charge/discharge control determination function 2001 will be explained using FIG. 21.

FIG. 21 shows the output range of power storage device 104 determined and applied to timetable 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, if there is a train in this range, priority is given to discharging, and if there is no train, priority is given to charging.

However, the charging priority range is determined by considering the overload limiter time range. For example, if priority is given to charging until just before train 1901 enters the output range of power storage device 104, and priority is given to discharging immediately after train 1901 enters the output range of power storage device 104, discharging will not be possible considering the overload limiter time range. There is a possibility that it will not happen.

Therefore, priority is given to charging at the time when train 1901 enters the output range of power storage device 104 minus the overload limiter time range.

In the area between the two lines 2101 and 2102 in FIG. 21, the area indicated by the broken line arrow is the charging priority, and the solid line arrow is the area indicating the discharging priority. In addition, a time period in which there is no arrow in the region indicates a time period in which there are no trains in the region, but charging is not prioritized considering the overload limiter time range. It should be noted that this area may not be in a state where priority is given to charging; for example, it may be set in a state where priority is given to discharging or there is no charging or discharging.

By doing this, it is possible to control to ensure the amount of charge when charging is prioritized, and it is possible to control to ensure the required large amount of power when discharging is prioritized. 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. The maximum charging power 1754 is the maximum charging power of the power storage device 104.

In addition, 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 The voltage lower than β is set as the second supply start voltage 1753. These α and β may be set to arbitrary positive values. The maximum charging power 1754 is set to "0".

The charging upper limit determination unit 1803 shown in FIG. 18 will be explained. When the maximum charging power 1754 is "0", the charging power 260 is set as the charging upper limit power 1851, and when the maximum charging power 1754 is other than "0", the maximum charging power 1754 is set as the charging upper limit power 1851. Through this process, when the charge/discharge control information 2051 indicates discharging, the same charging control as in the first and second embodiments is performed, and when the charge/discharge control information 2051 indicates other than discharging, the charging power is increased and the charging It will be possible to promote the securing of quantity.

With these functions, charging and discharging operations of the power storage device (power storage device 104) as a substation system are performed while ensuring the amount of charge of the power storage device 104, and it becomes possible to secure the necessary large amount of power.

Note that although this example is based on the service schedule, this schedule is not only a predetermined schedule, but also reflects constantly changing conditions such as information on trains running on the route. It may be something.

A railway power system according to a fourth embodiment 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, where solid lines represent the connection relationships between the systems 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 a power system and converts it into DC power, and a a first DC power converter 102 that converts DC power to power in a DC section; a second DC power converter 103 that converts the power of the first DC power converter 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 the power from the feeder line via the second DC power converter 103, and also charges the power from the feeder line. 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 system that receives AC power from the power system and converts it into DC power. A second power substation system having a second AC/DC power converter 1502, a first rectifier 1503 that converts DC power from the second AC/DC power converter 1502 into power in a DC section, and power from a feeder line. Based on the 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 the no-load voltage information 1551 of the first rectifier 1503. It has a control determination function 2202 that determines a first supply start voltage 2252, a second supply start voltage 2253, and a maximum charging power 2254.

The energy control function 2201 also 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 154 of the first DC power converter 102. Based on the first supply start voltage 2252, second supply start voltage 2253, and maximum charging power 2254, the control command 155 of the second DC power converter 103 and the first DC power converter 102 are determined. A control command 156 is determined. The same configurations as those described in Example 1 (FIG. 1) and Example 2 (FIG. 15) are designated by the same reference numbers as in FIGS. 1 and 15, and detailed description thereof will be omitted.

The energy control function 2201 will be explained using FIG. 23.

As shown in FIG. 23, the energy control function 2201 calculates the maximum discharge power 252 based on the voltage 151 of the feeder line, the amount of charge 153 of the power storage device 104, and the first supply start voltage 2252. The calculation function 2301, the overload limiter discharge power calculation function 202 that calculates the overload limiter discharge power limit 253 from the charge amount 153, and the minimum value selector 203 select between the maximum discharge power 252 and the overload limiter discharge power limit 253. The first DC power converter 102 can output based on the function of setting a small value as 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. 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 outputtable power 256, and calculate it as the control command 155 of the second DC power converter 103. Has a function.

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

The maximum discharge power calculation function 2301 is the same function as the maximum discharge power calculation function 1801 in FIG. Only the supply start voltage 2252 is used. Therefore, detailed explanation will be 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, a second supply start voltage 2253 is used. It's just using . Therefore, detailed explanation will be omitted.

Further, charging upper limit determining unit 2303 has the same function as charging upper limit determining unit 1803, and only uses maximum charging power 2254 instead of maximum charging power 1754, which is one of the inputs of charging upper limit determining unit 1803. It is. Therefore, detailed explanation will be omitted.

The control determination function 2202 will be explained using FIG. 24.

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 a voltage equal to or even β lower than the first supply start voltage 2252 is set as the second supply start voltage. The voltage is set to 2253. These α and β may be set to arbitrary positive values.

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

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

Note that the light load regeneration start voltage Va of the regenerative vehicle is extracted based on characteristic information of each train (not shown). The characteristic information for each train only needs to include the light load regeneration start voltage Va, and may consist of, for example, pulling force, braking force, electric brake force, light load regeneration start voltage, light load regeneration end voltage, etc. Good. If there is no regenerative vehicle, Va=0.

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

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

This completes the process. By doing this, only the light load portion of the regenerative vehicle is set to the maximum charging power, and as a result, unnecessary charging can be avoided.

With the configuration described above, the charging and discharging operation of the power storage device (power storage device) 104 as a substation system is performed as described in the first embodiment, and it becomes possible to secure the necessary large amount of power.

Note that 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 the present invention is not necessarily limited to having all the configurations described. Furthermore, it is possible to replace a 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. Further, it is possible to add, delete, or replace a part of the configuration of each embodiment with other configurations.

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.

101...First AC/DC power converter 102...First DC power converter 103...Second DC power converter 104...Power storage device (power storage device)
105... Energy control function 151... Voltage of feeder line 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 Control command (of the power converter 103) 156... Control command (of the DC power converter 102) 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 charging power calculation function 207...Overload limiter charging power calculation function 208...Charging 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...Outputtable power (of DC power converter 102) 257...Maximum charging power 258...Overload limiter Load limiter charging power limit 259... Regenerative charging start voltage 260... Charging power 261... Charging 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...(Previous) charge amount 452...Fluctuating charge amount 453...Fluctuating charge amount 454...Overload limiter judgment value 501...Discharge current calculation unit 502...Multiplier 503...Subtractor 504...Overload limiter calculation function 551...Discharge current 552...Discharge current square value 553...Thermal cooling performance 554...Discharge heat load 555...Overload limiter calculation time range 601 ...Overload limiter judgment 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... (previous) charge amount 952... Fluctuation charge amount 953... Fluctuation charge amount 954... Overload limiter judgment value 1001... Charging current calculation unit 1002... Multiplier 1003... Subtractor 1004... Overload limiter Calculation function 1051...Charging current 1052...Charging current square value 1053...Thermal cooling performance 1054...Charging thermal load 1055...Overload limiter calculation time range 1101...Overload limiter judgment table 1501...Energy control function 1502...Second AC/DC power conversion Device 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...Timetable management system 1703...Control determination function 1751...Timetable information 1752...First supply start voltage 1753...Second supply start voltage 1754...Maximum charging power 1801... Maximum discharge power calculation function 1802...Maximum output calculation function 1803...Charging upper limit determining unit 1804...Charging power command calculation function 1851...Charging upper limit power 1901, 1902, 1903, 1904, 1905...Train 2001...Charging/discharging control determining function 2002...Supply Starting voltage determining function 2051...Charging/discharging control information 2101, 2102...Output range of power storage device (power storage device) 2201...Energy control function 2202...Control determining function 2251a, 2251b, 2251c...(Train) position and power information 2252... First supply start voltage 2253...Second supply start voltage 2254...Maximum charging 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 the feeder line;
The first DC power converter is connected between the first DC power converter and the second DC power converter, and is charged with the power from the feeder line via the second DC power converter. a power storage device that discharges electricity to the feeder line via a DC power converter;
The first DC power converter is controlled to have an output below its rated capacity, and the power deficit in the second DC power converter is compensated for by discharging from the power storage device. substation system. The substation system according to claim 1,
When the output of the first DC power converter is larger than the load of the second DC power converter, the power storage device is controlled to be charged at a level equal to or less than the difference between the output and the load of the second DC power converter. The substation system according to claim 1 or 2,
A power substation system characterized in that when charging the power storage device from the second DC power converter, output of the first DC power converter is stopped. The substation system according to any one of claims 1 to 3,
A substation system characterized in that charging power is controlled so that the amount of heat generated by the power charging the power storage device is lower than the cooling performance of the power storage device. The substation system according to any one of claims 1 to 4,
A substation system, wherein the output performance of the power storage device is greater than or equal to the difference between the rated output of the second DC power converter and the rated output of the first DC power converter. 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 the power system into DC power;
further comprising another substation system different from the substation system having a first rectifier that converts the DC power from the second AC/DC power converter and outputs it to the feeder line,
An electric railway system characterized in that the voltage at which the substation system operates is controlled to be lower than the voltage at which the other substation system operates. The electric railway system according to claim 6,
Equipped with a timetable management system that has operation information for one or more trains,
An electric railway system characterized in that control of the substation system is determined based on the operation information. The electric railway system according to claim 6 or 7,
Equipped with a characteristic management system having characteristic information of one or more trains,
An electric railway system, wherein control of the substation system is determined based on the position, power, and characteristic information of the one or more trains. A method for controlling a substation system that uses a substation and a power storage device,
AC power from a substation is converted to DC power by an AC/DC power converter,
Converting the DC power from the AC/DC power converter to DC power in the DC section by a first DC power converter, and controlling the output of the first DC power converter to be 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 a second DC power converter,
A method of controlling a power substation system, comprising performing control so that a shortage of power in the second DC power converter is compensated for by discharging from a power storage device. A method of controlling a substation system according to claim 9,
If the output of the first DC power converter is larger than the load of the second DC power converter, the power storage device is controlled to be charged at a level equal to or less than the difference between the outputs of the first DC power converter and the second DC power converter. Control method. A method of controlling a substation system according to claim 9 or 10,
A method of controlling a substation system, comprising: stopping output of the first DC power converter when charging the power storage device from the second DC power converter. A method for controlling a substation system according to any one of claims 9 to 11,
A method for controlling a substation system, comprising controlling charging power so that the amount of heat generated by the power charging the power storage device is lower than the cooling performance of the power storage device. A method of controlling a substation system according to any one of claims 9 to 12,
A method for controlling a substation system, characterized in that the output performance of the power storage device is greater than or equal to the 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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