JP2000333373A - Distribution power supply system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a distribution power supply system for controlling the voltage of a power distribution system at a constant level, even if a plurality of distribution power supplies are connected to the power distribution system. SOLUTION: This distribution power supply system supplies power from a commercial power supply 1 to a load 10 that is connected to a power distribution line 8 via a power transmission line 2, a transformer 6 of a power distribution substation, a power transmission system circuit breaker 7, and the power distribution line 8 and supplies the AC power of the distribution power supply obtained from a system connection converter for converting a DC power from a DC power supply to an AC power to the power distribution line 8 via a connection reactor 12 and a power distribution system circuit breaker 11, and is provided with a control device 16 for inputting a system voltage and a system current from detectors 17 and 18, which are provided at the primary side of the connection reactor 12 and for controlling the distribution power supply. The control device 16 inputs a system voltage and a system current, at the same time inputs an output effective current command and an output reactive current command, and supplies power to the distribution power supply, while compensating for the reactive power to maintain the voltage of the power distribution line 8 at a constant level.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of supplying power from a commercial power supply to a power distribution system via a distribution switching device, and supplying the power to the distribution system via a distributed power switching device, an interconnection reactor, and a transformer. The present invention relates to a distributed power supply system configured to supply power to a distributed power supply obtained from an interconnection converter or a generator.

[0002]

2. Description of the Related Art A conventional control device for a distributed power supply will be described with reference to the related art. Here, the references are the Institute of Electrical Engineers of Japan, Power and Energy Division, New Energy Conservation Technical Committee, IEEJ Technical Report No. 609, "Urban Distributed Power Systems", Urban Distributed Power Systems, Urban Distributed Power Systems System Investigation Committee, October 1996.
FIG. 1 shows a configuration of a distributed power supply system of a reference document (common to the schematic configuration of the present invention). The upper commercial system comprises a transmission line 2 connected to a commercial power supply 1, a large-scale load 4 connected to the transmission line via a circuit breaker 3 and a circuit breaker 5, and a transformer 6 in a distribution substation. You.

In the distribution system, a distribution line 8 is connected to a transformer 6 via a circuit breaker 7. The distribution line 8 includes a small- and medium-sized load 10 via a circuit breaker 9 and a circuit breaker 11 and a distributed power supply system for power distribution to the area.

[0004] The distributed power supply system includes an interconnection reactor 1.
2. It comprises a transformer 13, a grid-connected converter or generator 14, a DC power supply or internal combustion / external combustion engine 15, and a control device 16 for distributed power supply.

FIG. 3 shows a vector diagram in a conventional distributed power system (common to the present invention). The DC power supply or the internal combustion / external combustion engine 15 generates DC power or generates power as needed. The grid-connected converter or generator 14 receives DC power or power and is controlled by the controller 16 of the distributed power supply to generate predetermined AC power. The distributed power supply control device 16 distributes power to loads in the target area. If the load factor in the target area rises, the controller 1
6 closes the circuit breaker 7 and receives power from the commercial system.

[0006] Further, even when the load factor in the target area decreases, the control device 16 of the distributed power supply closes the circuit breaker 7 in order to sell the surplus power.

The control unit 16 of the distributed power supply is
The voltage and current at each point are determined by the system voltage detector 17, the system current detector 18, and the voltage detector 17 and the current detector 18 attached to the primary side of the interconnection reactor 12 attached to the secondary side. Detect and determine the isolated operation state of the distributed power source. When the distributed power supply is operating independently, the circuit breaker 7 is disconnected to prevent the distributed power supply from operating alone.

Conventional distributed power sources include a cogeneration system using a gas engine or the like, a fuel cell power generation system, a solar power generation system, a wind power generation system, and a waste power generation system.
This will be described with reference to FIGS.

FIG. 19 shows a conventional cogeneration system, which comprises a gas turbine generator 80 and an exhaust gas boiler 81. The gas turbine generator 80 uses city gas or the like as fuel for heat (exhaust gas) and electricity ( Generated power). The exhaust gas boiler 81 is an energy saving system that seeks high thermal efficiency by collecting exhaust gas generated by the gas turbine generator 80.

[0010] As of October 1996, 3,300,00
0 kW or more is operating. For buildings, accommodation facilities are the largest (21% of the total). The power generation capacity of the accommodation facility is the largest at 125 MW output (23%). Diesel engines are the largest at 54%, 57%, and 55%, respectively, in the total number of installations, the number of installations, and the power generation output. In terms of the number of installed fuels, the ratio of heavy oil is the largest at 45%. At the national level, the majority are liquid fuel cogeneration systems, mainly diesel engines. In terms of power generation capacity, the proportion of heavy oil is the highest at 54%.

FIG. 20 shows a conventional fuel cell power generation system, in which chemical energy of fuel and oxidant is continuously converted into electric energy by an isothermal process. The fuel cell power generation system basically includes a fuel processor 82, a fuel cell main body 83, and an orthogonal transformer 84. As the fuel, hydrogen gas, natural gas, coal gas, petroleum, alcohols and the like are used. The fuel processor 82 converts the raw fuel into a gas having a high hydrogen content. The fuel cell main body 83 generates DC power by an electrochemical conversion reaction between the fuel and the oxidant at the electrodes. The main parts of the fuel cell are the electrolyte and the electrodes. The electrolyte has a function of sorting ions and electrons. Inside, only ions pass and electrons are blocked. The power generation function is in the electrodes. The chemical energy of the fuel is converted to electrical energy at the electrodes. Air is mainly used as the oxidizing agent. The orthogonal transformer 84 converts the DC power into AC power.

[0012] The characteristic of the power withstand network of the fuel cell is that it can be configured more simply than a conventional power plant because of direct power generation. In addition, since there is no rotor, the inertia is relatively small, and it is possible to quickly follow an electric load change, which is effective for improving the stability or reliability of the power circuit. Since the elements are electrically connected in series in order to obtain a higher output voltage, an arbitrary output voltage can be obtained, and with the optionality of the voltage class, various scale power generation systems ranging from small output to large output can be obtained. It is possible.

The features of the environmental resistance of a fuel cell are that the noise due to the small number of mechanical parts is relatively small, the main body does not have a combustor part, and the hydrocarbon gas is converted into a gas containing a large amount of hydrogen in a fuel processor. N in the body part to convert
Low generation of Ox and CO.

Further, since the unburned gas is recovered and reused, its existence does not cause a serious problem. Since the sulfur content is removed at the stage of the fuel gas, the emission from the fuel cell is extremely small. Further, since the power generation efficiency is high and the partial load characteristics are good, the amount of CO2 emission is small as compared with the power generation of internal and external combustion engines of the same scale.

As a feature of the efficiency of the fuel cell, this electrochemical reaction is an isothermal reaction and directly converts the free energy of the fuel into electric energy, so that the power generation efficiency is not governed by the Carno cycle. Can be expected.

Further, the partial load efficiency can be maintained as high as in the rated operation. The conventional distributed power system aims to distribute power to a target area. When necessary, power is received (purchased) or sold in cooperation with the commercial grid.

The most advanced development of fuel cells for consumer use,
There is a phosphoric acid fuel cell at the stage of commercialization. This fuel cell has a size of several tens of kW
It has been manufactured up to a few MW scale. The orthogonal transformer includes an inverter, an output transformer, an AC filter, and the like. An IGBT element or the like is employed as a main circuit of the inverter.

As the control, there is a case of a self-excited voltage type PWM system. A current control function has been added so that stable operation can be maintained even when the system is shaken, and a highly efficient and highly controlled converter has been completed. 4 bridges 2 to suppress harmonics
Four-phase multiplexing is used.

Further, an islanding detection function, which is essential for reverse power flow interconnection based on the grid interconnection guidelines, is incorporated in the inverter control. The operation modes correspond to grid interconnection and independent operation. In the standby mode, when the external power distribution system goes out of power, etc., it is possible to shift to the standby mode independently. are doing. In addition, power is mainly used in that area, but the surplus power flows back to the grid and controls received power. As an operation mode, a constant output operation or an output control operation is performed.

FIGS. 21 and 22 show a conventional photovoltaic power generation system. This system is expected to contribute to the peak cut of a commercial power system by using sunlight. 85, storage battery 86,
The one composed of the inverter 87 or the solar cell array 8
5, a new energy system including an inverter 87, a protection device 88, a watt hour meter 89, and a commercial system 90.

The government has also formulated the "New Energy Charter", which indicates introduction support such as introduction support, rationalization of regulations, technological development, standardization, etc., and is promoting its introduction.

This system provides a stable supply of energy
It is characterized by global environmental conservation and energy saving. As characteristic characteristics, (1) power generation efficiency is almost constant regardless of the size of the scale, (2) the degree of freedom of the power generation system is large, (3) the selection range of power generation capacity (light receiving area) is wide, (4) It can be used as a DC power supply.

In terms of reliability, (1) it is highly reliable because it is a complete stationary device, (2) it is reliable because it operates reliably in an emergency, and (3) it serves as a backup for other power generation. There are advantages.

The economics are (1) inexhaustible and free because the energy source is the sun, (2) sunlight is an effective use of abandoned energy, (3) mass-productivity, (4) economies of scale (5) No operating costs for fuel, lubricating oil, cooling water, etc. are required, (6) Energy saving, (7) Short energy recovery time, (8) No transportation costs for energy sources There are things.

The advantages of operability include (1)
Sunlight can be used in most places on the earth, (2) Simple operation, maintenance and inspection, (3) Easy automation and unmanned operation, (4) Power can be generated in consumption areas, (5) Does not require utilities such as auxiliary power, fuel, and cooling water even in an emergency. (6) Effective and environmentally friendly as an independent power source in areas where power transmission is not installed, such as remote islands, mountainous areas, deserts, grasslands, and undeveloped areas.
Sunlight is a clean and non-polluting energy source. (8) It is a pollution-free system because there is no concern about environmental pollution such as exhaust and exhaust heat. (9) It has no moving parts like a rotating machine. There is no problem such as noise, vibration and friction.

The disadvantages are as follows. In terms of performance, there are disadvantages such as (1) large installation space due to low energy density, (2) power generation output is affected by weather conditions (weather), and (3) no power generation at night. The disadvantage of economy is that the cost of the device is high.

Disadvantages of the operability are as follows: (1) When an AC power supply is required, DC / AC conversion by the inverter 1 is required. (2) When the power generation output is low in bad weather or at night, a stable power supply is required. (3) When installing a storage battery, it is necessary to secure, maintain, and inspect the installation space.

The solar cell directly converts light energy into electric energy using the quantum photoelectric effect of a semiconductor. Solar cells are composed of semiconductor pn junctions. When this is irradiated with light, electrons and holes are generated. This is the carrier. Electrons are attracted to the n-type and holes are attracted to the p-type by the electric field at the pn junction. As a result, the n-type is negatively charged and the p-type is positively charged. Therefore, when a load is connected between the p-type and the n-type, a current flows and power can be taken out. The maximum output power changes almost in proportion to the light intensity.

A solar cell that satisfies all aspects of efficiency, reliability, and cost is a silicon crystal system (single crystal, polycrystal, polycrystalline thin film, etc.). Conventional independent systems are independent of commercial power. The power consumption of the load is covered only by the power of solar power. (1) mountainous remote areas, (2) developing countries,
(3) Used in portable and mobile power generation systems, (4) Integrated solar cell, storage battery, and load systems. A solar cell is called a cell, and a panelized cell is called a module. Modules are practical units. The required number of modules is called an array.

The conventional system interconnection system preferentially uses the power generated by the solar cell and makes up for the insufficient power from the commercial power supply. If the output of the solar cell is not enough, switch to the power system. (System without reverse power flow) If the power generated by the solar cell is always connected to the power system and exceeds the power consumption, surplus power is reverse flowed and sold. (System with reverse power flow) An interconnection protection device for protection and safety confirmation when connecting to the power system is added. Inveru has a function to stop the system by detecting abnormalities in the solar cell and power system. The islanding detection function includes a third harmonic voltage distortion sudden increase detection method and a frequency shift method.

The advantages are that, in terms of economy, (1) there is no need to store power, (2) no expensive storage batteries are required, (3) surplus power can be sold to a power company, and (5) local (6) At night, power is supplied to the load by the power company. In terms of effectiveness,
(1) It is effective in peak cut in summer, and (2) Customers can receive power supply regardless of changes in solar radiation and weather.

FIGS. 23 and 24 show a conventional wind power generation system. The wind power generation system includes a wind power generator 91 having a rotor serving as a drive source and a controller 9.
2. A power generation system including a storage battery 93 and an inverter 94. Propeller type rotors are widely used. Generators include synchronous machines, induction machines, and variable speed systems.

An advantage of the propeller type is that, in terms of performance, the characteristic of the propeller type is that there is little fluctuation in torque for each rotation, that it has a self-driving force, and that it is possible to adjust the rotation speed and output to some extent by pitch control. In terms of environment, it is characterized by being clean and inexhaustible.

Disadvantages are that, in terms of performance, (1) the existing quantity changes over time or region, (2) the air density is low, and (3) the system quantity is large for the output capacity. .

In terms of economy, (1) the propeller type. (2) Induction motors do not require advanced control for interconnected operation, are low in cost and high in reliability, and (3) are expensive in variable speed systems. is there. In terms of controllability, (1) azimuth control is required for the propeller type, and (2) it is difficult to adjust the rotational speed of the synchronous machine for synchronization, so there is no possibility of practical use. Furthermore, there are environmental issues in terms of noise, landscape, and safety.

FIG. 25 shows a conventional waste power generation system. The waste power generation system is expected to support the problem of waste from the viewpoint of energy.
This system is a waste incinerator 98 → heat recovery device 99 →
Heat supply device 100 → heat supply device 101 → power generation device 102
Consists of Most of the recovered energy is an instantaneous system that cannot be stored or transported. As a feature,
First, in terms of performance, (1) a large output and (2) a stable power supply. In terms of effects, (1) promote the recycling of waste, (2) promote the reuse of waste, and (3) generate a large amount of surplus electricity.

In the voltage control and the reactive power control at the time of the reverse power flow operation of the conventional distributed power generation system, the generator reactive power control is performed by setting the power receiving reactive power to 10 in order to set the power receiving rate to 1.0 when receiving power. Had gone.

On the other hand, at the time of reverse power transmission, power receiving point power factor constant control is performed in order to maintain the voltage of the power distribution system constant. When the generator of the distributed power source is outputting power to the commercial system while the generator is operating in connection with the commercial system, the voltage of the commercial system increases. If the voltage on the commercial system side rises too much, a problem will occur for the loads connected in the same system.

Therefore, it is necessary to output power to the commercial power system while minimizing voltage rise. The voltage rise at the interconnection point is roughly expressed by the following equation.

ΔV1 (R · P + X · Q) / Vs (1) where P = active power sent from the distributed power generation system to the system, Q = reactive power sent from the distributed power generation system to the system, Vs = system Voltage, R = resistance of interconnection line, X = reactance of interconnection line Therefore, in order to make the voltage rise value at the interconnection point zero, the active power should be such that R · P + X · Q = 0 (2) What is necessary is just to control the reactive power Q with respect to P.

That is, as shown by the following equation, the reactive power may be received from the system side in proportion to the power sent to the commercial system side.

Q =-(R / X) P (3) That is, it is sufficient to receive the reactive power from the system side in proportion to the power sent to the commercial system. In this case, since the generator of the distributed power source is in the direction of the phase advance operation region, attention must be paid to the phase advance operation limit of the generator and the control of the phase advance capacitor connected to the local system.

[0043]

Problems to be solved by the cogeneration system include fuel and noise problems.
Regarding the problem of the fuel cell, in terms of reliability, there have been reports of many plant troubles related to electricity and control, particularly inverter-related troubles. Therefore reliability,
Further improvements in efficiency, durability and price are needed.

Disadvantages of solar power generation include (1) large installation space due to low energy density, and (2) power generation output is affected by weather conditions (weather).
(3) There is a disadvantage that power cannot be generated at night. The disadvantage of economy is the high cost of the equipment.

Disadvantages of operability are as follows: (1) When an AC power source is required, DC / AC conversion by an inverter is required.
(2) A storage battery is needed to obtain a stable power supply when the power generation output is low during bad weather or at night. (3) When installing a storage battery, it is necessary to secure the installation space, maintenance, and inspection. .

Solar power is environmentally friendly in that it utilizes natural energy. However, the generation of energy is unstable, and there are many problems in terms of simulation. As for future issues, in terms of solar cell manufacturing technology development aiming at high performance and low cost, (1) research on practical application of thin polycrystalline solar cell manufacturing technology, (2) thin film solar cell manufacturing technique Practical use research,
(3) Research on practical use of super-efficient solar cells needs to be promoted.

In addition, in terms of system technology development for making good use of solar cells, (1) plant research on grid interconnection, (2) plant research on various independent and distributed system technologies, (3) plant research on power supply systems,
It is necessary to conduct (4) improvement research of elemental technologies and (5) system evaluation research.

[0048] Further, the issues in peripheral technology development include (1) high efficiency compact inverter (transformerless) for grid-connected housing, (2) evaluation of grid-linked control technology, (3)
New storage batteries, (4) building material integrated modules, (5) various types of PV array installation methods, etc.

Other issues include a demonstration test of a photovoltaic power generation system, an international joint research demonstration, a feasibility study, a meteorological survey, and an IEA photovoltaic power generation system research cooperation.

The problem with wind power generators is that
There are issues of (1) weight reduction, (2) slimming, and (3) simplification.
Regarding the regionality of application, it should be put to practical use in areas where the stock is small. In addition, there are noise and landscape issues in the environment. As for maintainability, there is a problem of reducing operation costs.

In the power generation control system, (1)
Expansion of operable wind speed range, (2) Improvement of possibility of responding to wind direction and wind speed fluctuation, (3) Improvement of operation possibility with weak system,
There are (4) improvement of power quality at low output, and (5) development of power conversion and control systems that enable large capacity systems.

Wind power generation is environmentally friendly, similar to solar power generation, in that it utilizes natural energy. However, energy generation is still unstable, and there are many problems in terms of scale and noise.

The issues of the waste power generation system are (1)
There are items such as maximizing efficiency, (2) administrative issues (location constraints, environmental issues, laws and regulations, technical aspects), and (3) economy.

The distribution system having a plurality of distributed power sources composed of various types of distributed power sources has the following problems.

First, due to the low speed of the switching operation of the capacitor, there is a problem in the voltage stability of the power distribution system when the load changes suddenly, and it has been difficult to suppress the system voltage to the required accuracy.

Second, when a plurality of distributed power sources are installed in the same power distribution system, it is difficult to perform cooperative control thereof.

Third, it has been difficult for the conventional distributed power supply control device to simultaneously supply power to all loads on a platform where the number of loads has increased.

Fourth, it has been difficult to control the entire distribution system to easily supply the same capacity when the transmission system requires required power.

Fifth, there is a problem in the efficiency of the power interchange because the AC power is transmitted through a conventional substation.

Sixth, when interconnecting a plurality of systems at a substation, it is necessary to close a low-speed circuit breaker.
There were problems in durability, reliability, and performance.

Seventh, it was difficult to suppress harmonics during interconnection.

An object of the present invention is to control the voltage of the distribution system to be constant even when a plurality of distributed power sources are connected to the distribution system, and to continue the operation without stopping the entire system even when the load increases. When necessary, high-speed interconnection to other power transmission systems to control the coordination of multiple distributed power sources, ensure that the required power is transmitted to the power transmission system reliably and efficiently, and perform power interchange control among multiple power transmission systems It is to provide a distributed power system that can be used.

[0063]

In order to achieve the above object, an invention according to claim 1 is an apparatus for transmitting electric power from a commercial power supply to a transmission line, a transformer of a distribution substation, a transmission circuit breaker, and a distribution line. Supply to the load connected to the distribution line via
The AC power of a distributed power source obtained from a system interconnection converter that converts DC power from a DC power source into AC power or a generator that generates AC power based on rotational energy from an internal combustion / external combustion engine, an interconnection reactor, It is configured to supply to the distribution line via a distribution system breaker, and receives a system voltage detection value and a system current detection value from a system detector provided on a primary side of the interconnection reactor, and supplies the distributed power. In the distributed power supply system including a control device for controlling, the control device inputs the system voltage detection value and the system current detection value, inputs an output active current command and an output reactive current command, and controls the voltage of the distribution line. Is a distributed power supply system that supplies power to the distributed power supply while compensating for reactive power in order to keep the power supply constant.

In order to achieve the above object, a second aspect of the present invention provides a control device according to the first aspect, wherein the current control device, the output voltage command generation device, the control signal generation device, and the power distribution system circuit breaker are provided. The current control device receives the output active current command, the output reactive current command, the system voltage detection value, and the system current detection value, and the reactive power becomes zero. Output voltage command, the output voltage command generator is for inputting the voltage command to generate an output voltage command that can be generated by the system interconnection converter or the generator, the control signal The generator receives an output voltage command from the output voltage command generator, generates an output control signal, and provides the output control signal to the grid interconnection converter or the generator. The circuit breaker control device inputs the system voltage detection value and the system current detection value detected by the detector, and when the values are smaller than specified values, shuts off the power transmission system to prevent the discrete power supply from operating alone. The distribution system circuit breaker control device inputs the output voltage of the distributed power supply and the output current of the distributed power supply, and when the values are larger than specified values, outputs A distributed power system for outputting a control signal to the distribution system circuit breaker to prevent a current.

According to a third aspect of the present invention, in the above-described distributed power supply system, the control device inputs the system voltage detection value and the system current detection value and outputs an output voltage command. A distributed power supply system that inputs and supplies power to the distributed power supply while compensating for reactive power in order to keep the voltage of the distribution line constant.

In order to achieve the above object, the invention according to claim 4 is a control device according to claim 3, wherein the control device includes a voltage control device, a current control device, an output voltage command generation device, and a control signal generation device. A power distribution system breaker control device and a transmission system breaker control device, wherein the voltage control device inputs the output voltage command and the system voltage detection value and outputs a current command such that the reactive power becomes zero. The current control device inputs a current command from the voltage control device and the system current detection value and outputs a voltage command, and the output voltage command generation device outputs the voltage command from the voltage control device. A voltage command is input to generate an output voltage command that can be generated by the grid interconnection converter or the generator, and the control signal generator inputs an output voltage command from the output voltage command generator. An output control signal is generated, and the transmission system circuit breaker control device inputs a system voltage detection value and the system current detection value detected by the detector, and when the values are smaller than a specified value, the distribution The transmission system breaker control signal is output in order to prevent the isolated operation of the power supply, and the distribution system circuit breaker control device inputs the distribution voltage and the distribution current, and when the values are larger than a specified value. , A distributed power supply system that outputs a distribution system breaker control signal to prevent overvoltage and overcurrent.

According to the invention corresponding to any one of claims 1 to 4, even when the load suddenly changes, the voltage of the power distribution system is controlled at a high speed to a required accuracy to save power, and surplus / insufficient power is connected to the power system. Can sell electricity.

According to a fifth aspect of the present invention, in the above-described distributed power supply system, the control device keeps the voltage of the distribution line constant while controlling the phase with respect to the voltage of the distribution line. It is a distributed power system.

In order to achieve the above object, the invention according to claim 6 is a control device according to claim 5, wherein the control device is a phase control device, an output voltage generation device, a control signal generation device, and a distribution system breaker control. And a power transmission circuit breaker control device, wherein the phase control device inputs a phase angle command of an output voltage of the commercial power supply and a system voltage detection value of the commercial power supply and outputs a voltage command, and outputs the voltage command. The voltage generator is for inputting the voltage command to generate an output voltage command, the control signal generator is for generating a control signal corresponding to the output voltage command, and the power transmission system breaker control device is The system voltage detection value and the system current detection value are input, and when the values are smaller than the specified values, a control signal is output to the power transmission system circuit breaker to prevent the isolated operation of the distributed power source. The distribution system breaker control device inputs the distribution voltage and the distribution current, and when the values are larger than specified values, overvoltage and control signal to the distribution system breaker to prevent overcurrent. Is a distributed power supply system that outputs

According to the invention corresponding to claim 5 or claim 6, while the voltage of the distribution system is controlled to be constant by the reactive power compensating device, the power is easily sold to and from the system by phase control of the system voltage. It can be performed.

According to a seventh aspect of the present invention, in the above-described distributed power supply system, each of the control devices inputs the system voltage detection value and the system current detection value and outputs the output active current. A distributed power supply system that receives a command and an output reactive current command and supplies power to the distributed power supply while compensating for reactive power in order to keep the voltage of the distribution line constant.

According to the invention corresponding to claim 7, a plurality of distributed power sources arranged in the distribution system can control the voltage of the distribution system to be constant. Thereby, the stability of the voltage of the distribution system can be increased and the reliability can be improved.

In order to achieve the above object, the invention according to claim 8 is the above-mentioned distributed power system, wherein a series circuit of a reactor and a series compensator is connected between the transmission system circuit breaker and the distribution line. The control device inputs the system voltage detection value and the system current detection value, inputs an output active current command and an output reactive current command, and controls the series compensation device while controlling the voltage of the distribution line to be constant. And a voltage is applied to the reactor by applying a voltage to the reactor to supply power from the distribution line to the transmission line.

According to the invention corresponding to claim 8, the control device of the distributed power supply can realize efficient power trading by controlling the transmission power amount by the series compensator while keeping the voltage of the distribution system constant. .

According to a ninth aspect of the present invention, there is provided a distributed power supply system including a plurality of control devices for controlling the plurality of distributed power supplies, wherein the transmission line breaker and the distribution line are connected to each other. In the meantime, a series circuit of a reactor and a series compensator is connected, and each of the control devices inputs the system voltage detection value and the system current detection value, and inputs an output effective current command and an output invalid current command, A voltage is applied to the transmission line by the series compensator while the voltage of the distribution line is controlled to be constant, and a voltage is applied to the reactor, so that power is supplied from the distribution line to the transmission line. Power supply system.

According to the invention corresponding to claim 9, the control device of the plurality of distributed power supply systems controls the transmission power amount by the series compensator while maintaining the voltage of the distribution system constant, thereby improving the efficiency. Electricity trading can be realized.

According to a tenth aspect of the present invention, there is provided a distributed power supply system including a plurality of control devices for controlling the plurality of distributed power supplies, wherein the transmission line breaker and the distribution line are connected to each other. In the meantime, a series circuit of a reactor and a series compensator is connected, and each of the control devices inputs the system voltage detection value and the system current detection value, and inputs an output effective current command and an output invalid current command, Only one distributed power supply performs voltage control by the control device, and the other distributed power supplies perform current control by the other control device, and control the voltage of the distribution line to be constant while controlling the voltage of the distribution line. This is a distributed power supply system that supplies power to electric wires.

According to the tenth aspect of the present invention, while the voltage of the distribution system is controlled to be constant by one distributed power source control device, the other distributed power source control devices perform current control to provide a predetermined power. And the total amount of transmitted power can be controlled by the series compensator.

According to an eleventh aspect of the present invention, there is provided a distributed power supply system including a plurality of control devices for controlling the plurality of distributed power supplies, wherein the transmission system breaker and the distribution line are connected to each other. In the meantime, a series circuit of a reactor and a series compensator is connected, and each of the control devices inputs the system voltage detection value and the system current detection value, and inputs an output effective current command and an output invalid current command, Only one distributed power supply controls the current by the control device, and the other distributed power supply controls the voltage by the other control device, and controls the transmission line from the transmission line while controlling the voltage of the distribution line constant. This is a distributed power supply system that supplies power to electric wires.

According to the eleventh aspect of the present invention, only one distributed power supply controls the current, and the other distributed power supplies perform the voltage control. Electricity can be bought and sold with the power transmission system while controlling the transmission power by the device.

According to a twelfth aspect of the present invention, a first transmission line connected to a first commercial power supply and a second transmission line connected to a second commercial power supply are provided. A series circuit of an inter-system reactor and an inter-system series compensator is connected between electric wires, a distribution line is connected to each of the transmission lines via a transformer of a distribution substation, and a plurality of loads are connected to each of the distribution lines. And between each load and each distribution line,
A series circuit composed of a reactor and a series compensator is connected to each other via a power transmission circuit breaker, and is provided corresponding to a load connected to each distribution line, and converts DC power from a DC power supply into AC power. The AC power of a distributed power source obtained from a generator that generates AC power based on rotational energy from a system interconnection converter or an internal combustion / external combustion engine is connected to the distribution line via a interconnection reactor and a distribution system breaker, respectively. And a control device for inputting a system voltage detection value and a system current detection value from a system detector provided on the primary side of the interconnection reactor, and controlling the distributed power supply, And a distributed power supply system for performing power interchange between the second transmission line and the second transmission line.

According to the twelfth aspect of the present invention, a plurality of distribution systems including a plurality of distributed power supply systems having a series compensation device are connected to each other by the series compensation device, so that the plurality of distribution systems can be flexibly connected. Power interchange can be provided.

According to a thirteenth aspect of the present invention, there is provided an inter-system reactor connected between the first and second transmission lines and the inter-system series compensator. Is a distributed power supply system in which an AC switch is connected in series to the series circuit.

According to the thirteenth aspect of the present invention, a plurality of distribution systems including a plurality of distributed power supply systems having a series compensating device are connected to each other by an AC switch and a series compensating device. Flexible power interchange between distribution systems can be performed.

In order to achieve the above object, an invention according to claim 14 is the invention according to claim 12, wherein the inter-system reactor connected between the first and second transmission lines and the inter-system series compensator. Is a distributed power supply system in which a circuit breaker is connected in parallel to a series circuit.

According to the fourteenth aspect of the present invention, a plurality of distribution systems including a plurality of distributed power supply systems having a series compensator are connected by a series compensator and a circuit breaker connected in parallel to the series compensator. Even if the series compensator breaks down, by closing the circuit breaker, flexible power interchange between a plurality of power distribution systems can be ensured.

In order to achieve the above object, an invention according to claim 15 is the invention according to claim 12, wherein the inter-system reactor connected between the first and second transmission lines and the inter-system series compensator. Are connected in parallel to a series circuit of the above, and an AC switch is connected in series to these circuit breakers.

According to the invention corresponding to claim 15, a plurality of distribution systems consisting of a plurality of distributed power supply systems having a series compensator are connected by an AC switch to a series compensator and a circuit breaker connected in parallel to the series compensator. As a result, if necessary, multiple power distribution systems are interconnected and flexible power interchange is performed by a series compensator, and even if the series compensator fails, the circuit breaker is closed to ensure reliable power transmission between multiple power distribution systems. And flexible power interchange can be performed.

In order to achieve the above object, the invention according to claim 16 includes a first transmission line connected to the first commercial power supply and a second transmission line connected to the second commercial power supply. A series circuit of an inter-system reactor and an inter-system series compensator is connected between electric wires, a distribution line is connected to each of the transmission lines via a transformer of a distribution substation, and a plurality of loads are connected to each of the distribution lines. And between each load and each distribution line,
A series circuit composed of a reactor and a series compensator is connected to each other via a power transmission circuit breaker, and is provided corresponding to a load connected to each distribution line, and converts DC power from a DC power supply into AC power. The AC power of a distributed power source obtained from a generator that generates AC power based on rotational energy from a system interconnection converter or an internal combustion / external combustion engine is connected to the distribution line via a interconnection reactor and a distribution system breaker, respectively. And a control device for inputting a system voltage detection value and a system current detection value from a system detector provided on the primary side of the interconnection reactor, and controlling the distributed power supply, And a distributed power supply system for performing power interchange between the second transmission line and the second transmission line.

According to the sixteenth aspect of the present invention, a plurality of distribution systems including a plurality of distributed power systems having a series compensator are connected to each other by a distribution line having an active filter, thereby suppressing harmonics. In addition, flexible power interchange can be performed between a plurality of power distribution systems.

In order to achieve the above object, the invention according to claim 17 comprises a first transmission line connected to a first commercial power supply and a second transmission line connected to a second commercial power supply. A series circuit of an inter-system reactor and an inter-system series compensator is connected between electric wires, a distribution line is connected to each of the transmission lines via a transformer of a distribution substation, and a plurality of loads are connected to each of the distribution lines. And between each load and each distribution line,
A series circuit composed of a reactor and a series compensator is connected to each other via a power transmission circuit breaker, and is provided corresponding to a load connected to each distribution line, and converts DC power from a DC power supply into AC power. The AC power of a distributed power source obtained from a generator that generates AC power based on rotational energy from a system interconnection converter or an internal combustion / external combustion engine is connected to the distribution line via a interconnection reactor and a distribution system breaker, respectively. And a control device for inputting a system voltage detection value and a system current detection value from a system detector provided on the primary side of the interconnection reactor, and controlling the distributed power supply. This is a distributed power supply system that controls the power flow while controlling the voltage of all the distributed power supplies.

According to the invention corresponding to claim 17, a plurality of distribution systems composed of a plurality of distributed power supply systems having a series compensation device are connected by a series compensation device, and voltage control is performed by all distributed power supplies in each distribution system. By doing so, flexible power interchange can be performed between a plurality of distribution systems while maintaining the voltage of each distribution system constant.

In order to achieve the above object, the invention according to claim 18 is based on a first transmission line connected to a first commercial power supply and a second transmission line connected to a second commercial power supply. A series circuit of an inter-system reactor and an inter-system series compensator is connected between electric wires, a distribution line is connected to each of the transmission lines via a transformer of a distribution substation, and a plurality of loads are connected to each of the distribution lines. And between each load and each distribution line,
A series circuit composed of a reactor and a series compensator is connected to each other via a power transmission circuit breaker, and is provided corresponding to a load connected to each distribution line, and converts DC power from a DC power supply into AC power. The AC power of a distributed power source obtained from a generator that generates AC power based on rotational energy from a system interconnection converter or an internal combustion / external combustion engine is connected to the distribution line via a interconnection reactor and a distribution system breaker, respectively. And a control device for inputting a system voltage detection value and a system current detection value from a system detector provided on the primary side of the interconnection reactor, and controlling the distributed power supply, Is a distributed power supply system that controls the power flow while controlling the phases of all the distributed power supplies.

According to the invention corresponding to claim 18, a plurality of distribution systems composed of a plurality of distributed power supply systems having a series compensator are connected by a series compensator, and phase control is performed by all distributed power supplies of each distribution system. By doing so, the configuration of the control system can be facilitated and flexible power interchange can be performed between a plurality of power distribution systems.

[0095]

DESCRIPTION OF THE PREFERRED EMBODIMENTS <First Embodiment (Claims 1 and 2)
The first embodiment will be described with reference to FIGS. 1, 2, and 3. FIG. FIG. 1 is a block diagram showing the overall schematic configuration of the first embodiment. That is, the commercial power supply 1
And a large-scale load 4 connected through a circuit breaker 3 to a transmission line 2 connected through a circuit breaker 5 to a transformer 6 of a distribution substation via a power transmission system circuit breaker 7. A load 10 connected to the distribution line 8 via a circuit breaker 9, an interconnection reactor 12 connected to the distribution line 8 via a distribution system circuit breaker 11, a transformer 13 and a system interconnection converter or power generation. Machine 14, DC power supply or internal combustion / external combustion engine 15, and circuit breaker 7
The voltage at each point is determined by a system voltage detector 17, a system current detector 18, a voltage detector 19 attached to the primary side of the interconnection reactor 12, and a current detector 20 attached to the primary side of the system. It is the same as the conventional distributed power supply system in that a distributed power supply control device 16 for detecting a current is provided.

The distributed power supply control device 16 includes a voltage detector 17 for measuring a system voltage (detected value) Vs, that is, a voltage on the secondary side of the transformer 6 of the distribution substation, and a system current (detected value).
The system voltage Vs is determined by the current detector 18 for detecting Is.
And the system current Is, and one of the interconnection reactors 12
An output voltage and an output current are input from the voltage detector 19 and the current detector 20 on the next side.

FIG. 2 is a block diagram for explaining a specific configuration of the control device 16 of the distributed power supply according to the present embodiment. The current control device 21 outputs an effective current command Idref,
The reactive current command Iqref, the system voltage (detected value) Vs, and the system current (detected value) Is are input, and the voltage command Vref is output to the output voltage command generator 22.

The output voltage command generator 22 receives the voltage command Vref from the current controller 21 and outputs the output voltage command if both the transmission system (transmission line) 2 and the distribution system (distribution line) 8 are normal. The generating device 22 outputs the necessary voltage command V
out is output to the control signal generator 23.

The control signal generator 23 receives the voltage command Vout from the output voltage command generator 22 and outputs a control signal Vg to the system interconnection converter or the generator 14. The system interconnection converter or generator 14 receives the control signal Vg and generates an output voltage Vc shown in FIG.

The power transmission system circuit breaker control device 24 inputs the system voltage Vs and the system current Is. If the system voltage Vs or the system current Is is zero, the system circuit breaker disconnection command VSB And the circuit breaker 7 is disconnected.

The distribution system circuit breaker control device 25 receives the distributed power supply output voltage Vc and the distributed power supply output current Ic, and disconnects the distribution system circuit breaker 11 if an overvoltage or an overcurrent occurs.

Thus, voltage vector ΔV shown in FIG. 3 is applied to interconnection reactor 12. This voltage vector Δ
V causes an effective current ss shown in the interconnection reactor 12 to flow. As a result, power is transmitted from the distributed power source to the distribution line 8 and the transmission line 6.

According to the first embodiment described above, even when the load 10 changes suddenly, the voltage of the distribution line 8 is controlled at a high speed to the required accuracy to save power, and the surplus / insufficient power is sold to and from the system. It can be performed.

<Second Embodiment (corresponding to claims 3 and 4)
> A second embodiment will be described with reference to FIG.
FIG. 4 is a block diagram showing only the distributed power supply control device 16 in FIG. 1 of the first embodiment.

That is, a voltage control device 41 which receives an output voltage command Vcref and a system voltage (detection value) Vs, and outputs a current command Iref such that the reactive power becomes zero,
A current control device 42 that inputs a current command Iref and a system current (detection value) Is and outputs a voltage command Vref, an output voltage command generator 43 that receives a voltage command Vref and generates an output voltage command Vout that can be generated, Output voltage command V
out and a control signal generator 44 for generating an output control signal Vg.

The power transmission system circuit breaker control device 45 controls the system voltage V
s and the system current Is are input, and when the system voltage Vs or the system current Is is zero, the system breaker disconnection command VSB is output to prevent the islanding operation and the circuit breaker 7 is disconnected.

The distribution system circuit breaker control device 46 manually inputs the distributed power supply output voltage Vc and the distributed power supply output current Ic,
If it is an overvoltage or an overcurrent, a distribution system breaker disconnection command VCB is output to disconnect the breaker 7.

When both the power transmission system and the power distribution system are normal, the output voltage command generation device 43 outputs the necessary voltage command o.
ut is output to the control signal generator 44.

The control signal generator 44 outputs the control signal g to the system interconnection converter or generator 14 shown in FIG. This system interconnection converter or generator 14 receives the control signal Vg and generates an output voltage c shown in FIG. Thereby, voltage vector ΔV shown in FIG. 3 is applied to interconnection reactor 12. This voltage vector ΔV allows interconnection reactor 1
2, the effective current Iss shown in FIG. As a result, electric power is transmitted from the distributed power supply to the distribution system and the transmission system.

According to the second embodiment, the load 1 shown in FIG.
Even at the time of a sudden change of 0, it is possible to control the voltage of the power distribution system to the required accuracy at a high speed, and trade surplus / insufficient power with the system.

<Third Embodiment (corresponding to claims 5 and 6)
> A third embodiment will be described with reference to FIGS. FIG. 5 is a diagram showing the overall configuration of the third embodiment. The difference from the first embodiment is that the connection point between the distribution system circuit breaker 11 and the interconnection reactor 12 has a circuit breaker 26.
The difference is that the reactive power compensator 27 is connected via the. The reactive power compensator 27 is for controlling the voltage of the distribution system to be constant.

FIG. 6 is a block diagram showing only the control device 16 of the distributed power supply shown in FIG. 5. The control device 16 includes a phase control device 71, an output voltage command generation device 72, a control signal generation device 73, It is composed of a distribution system breaker control device 75 and a transmission system breaker control device 74.

The phase controller 71 receives the phase angle command θref of the output voltage of the commercial power supply 1 in FIG. 5 and the system voltage detection value Vs of the commercial power supply and outputs a voltage command Vref. The output voltage command generator 72 receives the voltage command Vref and generates an output voltage command Vout. The control signal generator 73 receives the output voltage command Vout, generates a control signal Vg corresponding to the output voltage command Vout, and outputs the control signal Vg to the grid interconnection converter or the generator 14.

The power transmission system circuit breaker control device 74 receives the system voltage detection value Vs and the system current detection value Is, and if the values are smaller than the specified values, for example, zero, in order to prevent the isolated operation of the distributed power source. A control signal (power transmission system circuit breaker disconnection command) VSB is output to the power transmission system circuit breaker 7, and the power transmission system circuit breaker 7 is disconnected.

The distribution system breaker control device 75 inputs the distributed power supply output voltage Vc and the distributed power supply output current Ic, and when the values are larger than the specified values, the distribution system breaker 11 controls the distribution system breaker 11 to prevent overvoltage and overcurrent. In this configuration, a control signal (distribution system breaker disconnection command) VCB is output to disconnect the distribution system breaker 11.
When both the transmission system and the distribution system are normal, in the control device 16 of the distributed power supply, the phase control device 71 inputs the phase angle command θref of the output voltage and the system voltage detection value Vs, and outputs the voltage command Vref to the output voltage command. When output to the generator 72, the output voltage command generator 72 gives the output voltage command Vout to the control signal generator 73.
3, a control signal Vg is supplied to a grid-connected converter or a generator 14;
Output to This grid-connected converter or generator 14
When the control signal Vg is input, a distributed power supply output voltage Vc shown in FIG. 3 is generated. Thereby, voltage vector ΔV shown in FIG. 3 is applied to interconnection reactor 12.

The effective current ss flows through the interconnection reactor 12 by this voltage. As a result, electric power is transmitted from the distributed power supply to the distribution system and the transmission system.

According to the above-described third embodiment, while the voltage of the distribution system is controlled to be constant by the reactive power compensator 27, it is possible to easily perform the power purchase and sale with the system by controlling the phase of the system voltage. Can be.

<Fourth Embodiment (Corresponding to Claim 7)> A fourth embodiment will be described with reference to FIG. FIG.
FIG. 9 is a configuration diagram illustrating an entire distributed power supply system according to a fourth embodiment. In this case, as shown in FIG.
In this configuration, a plurality of distributed power systems having the same configuration as that of the above are connected to each other.

The control unit 16 of the distributed power supply of each distributed power supply system performs constant voltage control and performs power transmission.

According to the fourth embodiment, a plurality of distributed power supplies connected to the power distribution system can control the voltage of the power distribution system to be constant. Thereby, the stability of the voltage of the distribution system can be increased and the reliability can be improved.

<Fifth Embodiment (corresponding to claim 8)> A fifth embodiment will be described with reference to FIG. FIG.
1 is different from the first embodiment of FIG. 1 only in that a series circuit of a series compensator 28 and a reactor 29 is newly connected between the power transmission system circuit breaker 7 and the distribution line 8.

In this case, the control device 16 of the distributed power supply is. While controlling the voltage of the distribution system to a constant value,
By applying a voltage to the power transmission system and applying a voltage to the reactor 29, power is supplied from the power distribution system to the power transmission system.

According to the fifth embodiment, the distributed power supply controller 16 can realize efficient power trading by controlling the amount of transmitted power by the series compensator 28 while maintaining the voltage of the distribution system constant.

<Sixth Embodiment (corresponding to claim 9)> A sixth embodiment will be described with reference to FIG.
The difference from FIG. 8 is that a plurality of distributed power supply systems excluding the reactor 29 and the series compensator 28 in FIG. 8 are connected to the common distribution line 08. The plurality of distributed power supply systems connected to the common distribution line 08 all perform voltage control, and control the voltage of the distribution line 8 to be constant. The series compensator 28 on the interconnection between the power transmission system and the distribution system performs power buying and selling by applying a voltage to the reactor 29.

According to the sixth embodiment, the control devices of the plurality of distributed power supply systems control the amount of power transmitted by the series compensator while maintaining the voltage of the power distribution system at a constant level, thereby enabling efficient power trading. Can be realized.

<Seventh Embodiment (Corresponding to Claim 10)>
A seventh embodiment will be described with reference to FIG.
FIG. 10 has the same configuration of the system of FIG. 9 except for the following points. That is, one distributed power supply system connected to the common distribution line 08 is configured to perform voltage control, and the control device of the distributed power supply in another distributed power supply system connected to the common distribution line 08 performs current control. Do. In this case, the series compensator 2 on the interconnection between the transmission system and the distribution system
8 performs power sale by applying a voltage to the reactor 29.

According to the seventh embodiment, while the voltage of the distribution system is kept constant by one distributed power source control device, the other distributed power source control devices perform current control to transmit predetermined power. The total amount of transmitted power can be controlled by the series compensator.

<Eighth Embodiment (corresponding to claim 11)>
An eighth embodiment will be described with reference to FIG.
The power transmission system is connected to the secondary side of a commercial power supply 1 having a voltage Vs, a transmission line 2, a load 4 connected through a circuit breaker 3, and a transformer 6 in a distribution substation connected through a circuit breaker 5. Power distribution system.

The distribution system is composed of a plurality of distributed power supply systems connected to the common distribution line 08. Each distributed power system includes a transmission system breaker 7, a reactor 29, a series compensator 28, a load 10 via a circuit breaker 9, an interconnection reactor 12 via a distribution system breaker 11, and a transformer 1 for a converter.
3. Consisting of a system interconnection converter or generator 14, a DC power supply or internal combustion / external combustion engine 15, and a control device 16 for distributed power supply.

The control device 16 of the distributed power supply inputs the system voltage and the system current from the voltage detector 17 for measuring the voltage on the secondary side of the transformer 6 of the distribution substation and the current detector 18 for detecting the system current. At the same time, an output voltage and an output current are input from the voltage detector 19 and the current detector 20 on the primary side of the interconnection reactor 12.

In this distribution system, the common distribution line 08
Only one distributed power supply system connected to the common distribution line 08 performs current control, and all other distributed power supply systems connected to the common distribution line 08 perform voltage control.

According to the eighth embodiment, only one distributed power supply controls the current, and the other distributed power supplies perform the voltage control, so that the power is transmitted by the series compensator while controlling the voltage of the distribution system at a constant level. Electricity can be traded with the power transmission system while controlling electric power.

<Ninth embodiment (corresponding to claim 12)>
The ninth embodiment will be described with reference to FIG.
In this embodiment, a plurality of power transmission systems including a plurality of commercial power sources 1 and a plurality of transmission lines 2 are connected to a reactor 29A.
This is a case where a single series circuit composed of a series compensator 28A and a series compensator 28A is connected.

More specifically, an inter-system connection is provided between a first transmission line 2 connected to the first commercial power source 1 and a second transmission line 2 connected to the second commercial power source 1. Reactor 29A
And a series circuit of the inter-system series compensator 28A, and a common distribution line 08, 08 is connected to each transmission line 2, 2 via a transformer of a distribution substation, respectively.
, A plurality of loads 10 are respectively connected via circuit breakers 9, and a reactor 29 is connected between each load 10 and each common distribution line 08, 08 via a power transmission system circuit breaker 7.
And a series circuit composed of a series compensator 28, which is provided corresponding to the load 10 connected to each of the distribution lines 8, 8, and converts the DC power from the DC power supply 15 into AC power. System converter 14 or internal combustion / external combustion engine 15
A configuration is such that AC power of a distributed power source obtained from a generator 14 that generates AC power based on rotational energy from is supplied to each distribution line 8 via an interconnection reactor 12 and a distribution system breaker 11, respectively. It has a control device 16 that inputs a system voltage detection value from a system voltage detector 19 and a system current detection value from a system current detector 20 provided on the primary side of the interconnection reactor 12 and controls a distributed power supply. is there.

According to the ninth embodiment, the series compensator 2
By connecting a series circuit consisting of an inter-system reactor 29A and an inter-system series compensator 28A between the first and second transmission lines 2 and 2 comprising a plurality of distributed power systems having And flexible power interchange can be performed.

<Tenth embodiment (corresponding to claim 13)
The tenth embodiment will be described with reference to FIG. The present embodiment is different from the embodiment of FIG. 12 in that a series circuit of an inter-system reactor 29A and an inter-system series compensator 28A connected between the first and second transmission lines 2 and 2 is connected in series. This is a point where the AC switch 30 is connected, and the other points are the same as those in FIG.

According to the tenth embodiment, by closing the AC switch 30, flexible power interchange between a plurality of power distribution systems can be performed as needed.

<Eleventh Embodiment (corresponding to claim 14)
The eleventh embodiment will be described with reference to FIG. This embodiment differs from the embodiment of FIG.
A point that a circuit breaker 47 is connected in parallel to the series circuit of the inter-system reactor 29A and the inter-system series compensator 28A that is connected between the first and second transmission lines 2 and 2; It is the same as FIG.

According to the eleventh embodiment, even when the inter-system series compensator 28A fails, the circuit breaker 47 is closed, so that flexible power interchange can be reliably performed between a plurality of power distribution systems. .

<Twelfth Embodiment (corresponding to claim 15)
The twelfth embodiment will be described with reference to FIG. In this embodiment, a circuit in which a circuit breaker 47 is connected in parallel to a series circuit of the reactor 29 and the series compensator 28 of the embodiment shown in FIG.
FIG. 14 shows that an AC switch 30 is newly connected in series.
This is a different point.

According to the twelfth embodiment, a plurality of power distribution systems are interconnected as necessary, and flexible power interchange is performed by the inter-system series compensator 28A.
Even if a failure occurs, by closing the circuit breaker 47, flexible power interchange between a plurality of power distribution systems can be ensured.

<Thirteenth embodiment (corresponding to claim 16)
> A thirteenth embodiment will be described with reference to FIG. This embodiment bears the transmission lines 2 and 2 of the embodiment of FIG.
The only difference from FIG. 12 is that an active filter 32 for suppressing harmonics is connected to this part without providing a series circuit of the inter-system reactor 29A and the inter-system series compensator 28A connected therebetween. Is a point.

According to the thirteenth embodiment, the active filter 32 enables flexible power interchange between a plurality of distribution systems while suppressing harmonics.

<Fourteenth Embodiment (corresponding to claim 17)
> A fourteenth embodiment will be described with reference to FIG. This embodiment has the same configuration as the embodiment of FIG.
A series circuit of an inter-system reactor 29A and an inter-system series compensator 28A is connected between the transmission lines 2 and 2, thereby controlling the power flow while voltage-controlling all the distributed power supply systems between the transmission lines 2 and 2. This is a different point from FIG.

According to the fourteenth embodiment, voltage control is performed by all distributed power sources in each distribution system, so that flexible power interchange can be performed between a plurality of distribution systems while maintaining a constant voltage in each distribution system. it can.

<Fifteenth Embodiment (corresponding to claim 18)
> A fifteenth embodiment will be described with reference to FIG. This embodiment bear has the same configuration as the embodiment of FIG.
A series circuit of an inter-system reactor 29A and a series compensator 28A is connected between the transmission lines 2 and 2, whereby the transmission lines 2 and 2 are connected.
The difference from FIG. 12 is that the power flow is controlled while controlling the phases of all the distributed power systems between the two.

According to the fifteenth embodiment, the phase control is performed by all the distributed power supply systems of each distribution system, whereby the configuration of the control system can be simplified, and flexible power interchange can be performed among a plurality of distribution systems.

[0148]

According to the present invention, even when a plurality of distributed power sources are connected to the distribution system, the voltage of the distribution system is controlled to be constant, and even if the load increases, the operation can be performed without stopping the entire system. Continue, if necessary, connect to other power transmission systems at high speed, coordinated control of multiple distributed power sources, reliably and efficiently transmit required power to power transmission systems, and perform power interchange control between multiple power transmission systems And a distributed power supply system capable of providing the same.

[Brief description of the drawings]

FIG. 1 is a diagram showing an overall configuration of a distributed power system according to a first embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of the distributed power supply control device of FIG. 1;

FIG. 3 or a conventional vector diagram.

FIG. 4 is a block diagram showing a configuration of a distributed power supply control device according to a second embodiment of the distributed power supply system of the present invention.

FIG. 5 is a diagram showing an entire configuration of a distributed power supply system according to a third embodiment of the present invention.

FIG. 6 is a block diagram showing a configuration of the distributed power supply control device of FIG. 5;

FIG. 7 is a diagram showing an overall configuration of a distributed power system according to a fourth embodiment of the present invention.

FIG. 8 is a diagram showing an overall configuration of a distributed power system according to a fifth embodiment of the present invention.

FIG. 9 is a diagram showing an overall configuration of a distributed power system according to a sixth embodiment of the present invention.

FIG. 10 is a diagram showing an overall configuration of a distributed power system according to a seventh embodiment of the present invention.

FIG. 11 is a diagram showing an entire configuration of a distributed power system according to an eighth embodiment of the present invention.

FIG. 12 is a diagram showing an entire configuration of a ninth embodiment of the distributed power supply system of the present invention.

FIG. 13 is a diagram showing an entire configuration of a distributed power supply system according to a tenth embodiment of the present invention.

FIG. 14 is a diagram showing an overall configuration of a distributed power supply system according to an eleventh embodiment of the present invention.

FIG. 15 is a diagram showing an entire configuration of a distributed power supply system according to a twelfth embodiment of the present invention.

FIG. 16 is a diagram showing an overall configuration of a distributed power system according to a thirteenth embodiment of the present invention.

FIG. 17 is a diagram showing an overall configuration of a distributed power system according to a fourteenth embodiment of the present invention.

FIG. 18 is a diagram showing an entire configuration of a distributed power system according to a fifteenth embodiment of the present invention.

FIG. 19 is a diagram for explaining a conventional cogeneration system.

FIG. 20 is a view for explaining a conventional fuel cell power generation system.

FIG. 21: Conventional solar power generation system (independent system)
FIG.

FIG. 22 is a view for explaining a conventional photovoltaic power generation system (system interconnection system).

FIG. 23 is a view for explaining a conventional wind power generation system (independent system).

FIG. 24 is a view for explaining a conventional wind power generation system (grid interconnection system).

FIG. 25 is a view for explaining a conventional waste power generation system.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Commercial power supply 2 ... Transmission line 3 ... Circuit breaker 4 ... Load 5 ... Circuit breaker 6 ... Distribution substation transformer 7 ... Transmission system circuit breaker 8 ... Distribution line 08 ... Common distribution line 9 ... Circuit breaker 10 ... Load 11 ... distribution system circuit breaker 12 ... interconnection reactor 13 ... transformer transformer 14 ... system interconnection converter or generator 15 ... DC power supply or internal combustion / external combustion engine 16 ... distributed power supply control device 17 ... voltage detector 18 ... Current detector 19 ... Voltage detector 20 ... Current detector 21 ... Current controller 22 ... Output voltage command generator 23 ... Control signal generator 24 ... Transmission system circuit breaker controller 25 Distribution system circuit breaker controller 26 ... Circuit breaker 27 ... reactive power compensator 28 ... series compensator 28A ... inter-system series compensator 29 ... reactor 29 ... inter-system reactor 30 ... AC switch 32 ... active filter 41 ... voltage control Device 42 ... Current control device 43 ... Output voltage command generation device 44 ... Control signal generation device 45 ... Transmission system breaker control device 46 ... Distribution system breaker control device 47 ... Circuit breaker 71 ... Phase control device 72 ... Output voltage command generation Device 73: Control signal generator 74: Transmission system circuit breaker controller 75: Distribution system circuit breaker controller

 ────────────────────────────────────────────────── ─── Continuing from the front page (72) Inventor Hajime Yamamoto 1 Toshiba-cho, Fuchu-shi, Tokyo F-term in the Fuchu factory of Toshiba Corporation 5G015 GA06 GA15 HA16 JA11 JA22 5G066 DA04 DA08 FA01 FB11 FB17 FC11 HA19 HB02 HB05

Claims (18)

[Claims] 1. A power supply from a commercial power supply is supplied to a load connected to a distribution line via a transmission line, a transformer of a distribution substation, a transmission system circuit breaker, and a distribution line. AC power of a distributed power source obtained from a grid-connected converter that converts power to AC power or a generator that generates AC power based on rotational energy from an internal combustion / external combustion engine is connected to a grid-connected reactor and a distribution system breaker. A control device configured to supply the power to the distribution line via a system voltage detection value and a system current detection value from a system detector provided on the primary side of the interconnection reactor, and to control the distributed power supply. In the distributed power supply system provided, the control device inputs the system voltage detection value and the system current detection value, inputs an output active current command and an output reactive current command, and keeps the voltage of the distribution line constant. , Distributed power supply system is characterized in that so as to supply power to the distributed power supply while compensating for the reactive power. 2. The current control device according to claim 1, wherein the control device includes a current control device, an output voltage command generation device, a control signal generation device, a distribution system breaker control device, and a transmission system breaker control device. The output effective current command, the output reactive current command, a system voltage detection value, and a system current detection value, and outputs a voltage command such that the reactive power becomes zero. The voltage command is input to generate an output voltage command that can be generated by the grid interconnection converter or the generator.The control signal generator inputs and outputs an output voltage command from the output voltage command generator. Generating a control signal and providing the output control signal to the grid interconnection converter or the generator. The transmission system circuit breaker control device includes a grid voltage detection value and a grid voltage detection value detected by the detector. And inputting the system current detection value, and when the value is smaller than a specified value, outputting a control signal to the power transmission system circuit breaker to prevent the isolated operation of the distributed power source. The circuit breaker control device inputs the output voltage of the distributed power supply and the output current of the distributed power supply, and when the values are larger than specified values, overvoltage and control signal to the distribution system circuit breaker to prevent overcurrent. The distributed power supply system according to claim 1, wherein the distributed power supply system outputs: 3. A power supply from a commercial power supply is supplied to a load connected to the distribution line via a transmission line, a transformer in a distribution substation, a transmission circuit breaker, and a distribution line. AC power of a distributed power source obtained from a grid-connected converter that converts power to AC power or a generator that generates AC power based on rotational energy from an internal combustion / external combustion engine is connected to a grid-connected reactor and a distribution system breaker. A control device configured to supply the power to the distribution line via a system voltage detection value and a system current detection value from a system detector provided on the primary side of the interconnection reactor, and to control the distributed power supply. In the distributed power supply system provided, the control device inputs the system voltage detection value and the system current detection value, inputs an output voltage command, and compensates for reactive power in order to keep the voltage of the distribution line constant. What Distributed power supply system is characterized in that so as to supply power to et the dispersed power source. 4. The control device includes a voltage control device, a current control device, an output voltage command generation device, a control signal generation device, a distribution system breaker control device, and a transmission system breaker control device. The voltage control device inputs the output voltage command and the system voltage detection value, and outputs a current command such that the reactive power becomes zero. The current control device outputs a current command from the voltage control device. And outputs a voltage command by inputting the system current detection value, and the output voltage command generation device inputs a voltage command from the voltage control device and can generate the system interconnection converter or the generator. An output voltage command is generated, and the control signal generator receives an output voltage command from the output voltage command generator and generates an output control signal. Receives the system voltage detection value and the system current detection value detected by the detector, and when the values are smaller than a specified value, transmits the transmission system circuit breaker control signal to prevent the isolated operation of the distributed power supply. The distribution system breaker control device inputs the distribution voltage and the distribution current, and when the values are greater than a specified value, overvoltage, a distribution system breaker control signal to prevent overcurrent. The distributed power supply system according to claim 3, wherein the output is output. 5. A power supply from a commercial power supply is supplied to a load connected to the distribution line via a transmission line, a transformer of a distribution substation, a transmission circuit breaker, and a distribution line. AC power of a distributed power source obtained from a grid-connected converter that converts power to AC power or a generator that generates AC power based on rotational energy from an internal combustion / external combustion engine is connected to a grid-connected reactor and a distribution system breaker. A reactive power compensator connected to the system interconnection converter or generator, and a system voltage detection value from a system detector provided on the primary side of the interconnection reactor And a control device for inputting a system current detection value and controlling the distributed power supply, wherein the control device keeps the voltage of the distribution line constant while controlling the phase with respect to the voltage of the distribution line. Distributed power system according to claim. 6. The control device includes a phase control device, an output voltage generation device, a control signal generation device, a distribution system breaker control device, and a transmission system breaker control device, and the phase control device includes: A phase angle command of an output voltage of a commercial power supply and a system voltage detection value of the commercial power supply are input to output a voltage command, and the output voltage generating device receives the voltage command and generates an output voltage command. The control signal generator is for generating a control signal corresponding to the output voltage command, the power transmission system breaker control device inputs the system voltage detection value and the system current detection value, and the value is If the value is smaller than a specified value, a control signal is output to the transmission system circuit breaker in order to prevent the isolated operation of the distributed power source. If the value entered fine the distribution current is greater than the specified value, distributed power system of claim 5, wherein outputs a control signal to the power distribution system circuit breaker in order to prevent overvoltage, overcurrent. 7. A power supply from a commercial power supply is supplied to a plurality of loads connected to the distribution line via a transmission line, a transformer of a distribution substation, a transmission system circuit breaker, and a distribution line. AC of a plurality of distributed power sources obtained from a plurality of grid-connected converters that convert DC power from a power source into AC power or a plurality of generators that generate AC power based on rotational energy from a plurality of internal combustion / external combustion engines Power is supplied to the distribution line via a plurality of interconnection reactors and a plurality of distribution system circuit breakers, and system voltage detection from a plurality of system detectors provided on a primary side of each interconnection reactor Value and system current detection value,
In the distributed power system including a plurality of control devices that control the plurality of distributed power sources, each of the control devices inputs the system voltage detection value and the system current detection value, and outputs an output active current command and an output reactive current command. And supplying power to the distributed power supply while compensating for reactive power in order to keep the voltage of the distribution line constant. 8. A power supply from a commercial power supply is supplied to a load connected to the distribution line via a transmission line, a transformer of a distribution substation, a transmission circuit breaker, and a distribution line. AC power of a distributed power source obtained from a grid-connected converter that converts power to AC power or a generator that generates AC power based on rotational energy from an internal combustion / external combustion engine is connected to a grid-connected reactor and a distribution system breaker. A control device configured to supply the power to the distribution line via a system voltage detection value and a system current detection value from a system detector provided on the primary side of the interconnection reactor, and to control the distributed power supply. In the distributed power system provided, a series circuit of a reactor and a series compensator is connected between the power transmission system circuit breaker and the distribution line, and the control device inputs the system voltage detection value and the system current detection value. Both, input the output effective current command and the output reactive current command, while controlling the voltage of the distribution line to be constant, a voltage is applied to the transmission line by the series compensator, and a voltage is applied to the reactor. And a power supply from the distribution line to the transmission line. 9. A power supply from a commercial power supply is supplied to a plurality of loads connected to the distribution line via a transmission line, a transformer of a distribution substation, a transmission system circuit breaker, and a distribution line. AC power of a distributed power source obtained from a plurality of grid-connected converters that convert DC power from a power source into AC power or a plurality of generators that generate AC power based on rotational energy from a plurality of internal combustion / external combustion engines. , Each configured to be supplied to the distribution line via a distribution system breaker, and a system voltage detection value and a system current detection value from a system detector provided on a primary side of each of the connection reactors. In the distributed power supply system comprising a plurality of control devices for inputting and controlling the plurality of distributed power supplies, a series circuit of a reactor and a series compensator is connected between the transmission system circuit breaker and the distribution line, Control equipment The installation is
While inputting the system voltage detection value and the system current detection value, inputting an output active current command and an output reactive current command, while controlling the voltage of the distribution line to be constant, the series compensator applies a voltage to the transmission line. Is applied, and a voltage is applied to the reactor to supply power from the distribution line to the transmission line. 10. A power supply from a commercial power supply is supplied to a plurality of loads connected to the distribution line via a transmission line, a transformer of a distribution substation, a transmission circuit breaker, and a distribution line, and a plurality of direct currents are supplied. AC power of a distributed power source obtained from a plurality of grid-connected converters that convert DC power from a power source into AC power or a plurality of generators that generate AC power based on rotational energy from a plurality of internal combustion / external combustion engines. , Each configured to be supplied to the distribution line via a distribution system breaker, and a system voltage detection value and a system current detection value from a system detector provided on a primary side of each of the connection reactors. In the distributed power supply system including a plurality of control devices for inputting and controlling the plurality of distributed power supplies, a series circuit of a reactor and a series compensator is connected between the transmission system circuit breaker and the distribution line; control Location is,
The system voltage detection value and the system current detection value are input, an output active current command and an output reactive current command are input, and only the one distributed power source performs voltage control by the control device. A distributed power supply system, wherein electric power is supplied from the distribution line to the transmission line while current control is performed by the other control device to control the voltage of the distribution line constant. 11. A power supply from a commercial power supply is supplied to a plurality of loads connected to a distribution line via a transmission line, a transformer of a distribution substation, a transmission circuit breaker, and a distribution line. AC power of a distributed power source obtained from a plurality of grid-connected converters that convert DC power from a power source into AC power or a plurality of generators that generate AC power based on rotational energy from a plurality of internal combustion / external combustion engines. , Each configured to be supplied to the distribution line via a distribution system breaker, and a system voltage detection value and a system current detection value from a system detector provided on a primary side of each of the connection reactors. In the distributed power supply system including a plurality of control devices for inputting and controlling the plurality of distributed power supplies, a series circuit of a reactor and a series compensator is connected between the transmission system circuit breaker and the distribution line; control The equipment is
While inputting the system voltage detection value and the system current detection value, inputting an output active current command and an output reactive current command, the current control is performed only by the one distributed power supply by the control device, and the remaining other distributed power supplies are A distributed power supply system, wherein the power supply is performed from the distribution line to the transmission line while voltage control is performed by the other control device and the voltage of the distribution line is kept constant. 12. A first power supply connected to a first commercial power supply
And a series circuit of an inter-system reactor and an inter-system series compensator between the second transmission line connected to the second commercial power supply, A distribution line is connected via a transformer, a plurality of loads are connected to the respective distribution lines, and a reactor and a series compensator are provided between the respective loads and the respective distribution lines via a power transmission circuit breaker. Connected in series with each other and provided corresponding to the load connected to each of the distribution lines,
The AC power of a distributed power source obtained from a system interconnection converter that converts DC power from a DC power source into AC power or a generator that generates AC power based on rotational energy from an internal combustion / external combustion engine is connected to the interconnection reactor, respectively. , Configured to supply to each of the distribution lines via a distribution system circuit breaker, input a system voltage detection value and a system current detection value from a system detector provided on the primary side of the interconnection reactor, and A distributed power supply system comprising a control device for controlling a power supply, wherein power is interchanged between the first and second transmission lines. 13. An AC switch is connected in series between the first and second transmission lines to a series circuit of the inter-system reactor and the inter-system series compensator connected. 13. The distributed power supply system according to item 12. 14. A circuit breaker is connected between the first and second transmission lines in parallel with a series circuit of the inter-system reactor and the inter-system series compensator connected. 13. The distributed power supply system according to item 12. 15. A circuit breaker is connected between the first and second transmission lines in parallel with the inter-system reactor and the series circuit of the inter-system series compensator, and an AC switch is connected in series with the circuit breaker. 13. The distributed power supply system according to claim 12, wherein 16. A first power supply connected to a first commercial power supply
And a series circuit of an inter-system reactor and an inter-system series compensator between the second transmission line connected to the second commercial power supply, A distribution line is connected via a transformer, a plurality of loads are connected to the respective distribution lines, and a reactor and a series compensator are provided between the respective loads and the respective distribution lines via a power transmission circuit breaker. Connected in series with each other and provided corresponding to the load connected to each of the distribution lines,
The AC power of a distributed power source obtained from a system interconnection converter that converts DC power from a DC power source into AC power or a generator that generates AC power based on rotational energy from an internal combustion / external combustion engine is connected to the interconnection reactor, respectively. , Configured to supply to each of the distribution lines via a distribution system circuit breaker, input a system voltage detection value and a system current detection value from a system detector provided on the primary side of the interconnection reactor, and A distributed power supply system comprising a control device for controlling a power supply, wherein power is interchanged between the first and second transmission lines. 17. A first power supply connected to a first commercial power supply
And a series circuit of an inter-system reactor and an inter-system series compensator between the second transmission line connected to the second commercial power supply, A distribution line is connected via a transformer, a plurality of loads are connected to the respective distribution lines, and a reactor and a series compensator are provided between the respective loads and the respective distribution lines via a power transmission circuit breaker. Connected in series with each other and provided corresponding to the load connected to each of the distribution lines,
The AC power of a distributed power source obtained from a system interconnection converter that converts DC power from a DC power source into AC power or a generator that generates AC power based on rotational energy from an internal combustion / external combustion engine is connected to the interconnection reactor, respectively. , Configured to supply to each of the distribution lines via a distribution system circuit breaker, input a system voltage detection value and a system current detection value from a system detector provided on the primary side of the interconnection reactor, and A distributed power supply system, comprising: a control device for controlling a power supply; and performing power flow control while voltage-controlling all of the distributed power supplies of both systems. 18. A first power supply connected to a first commercial power supply
And a series circuit of an inter-system reactor and an inter-system series compensator between the second transmission line connected to the second commercial power supply, A distribution line is connected via a transformer, a plurality of loads are connected to the respective distribution lines, and a reactor and a series compensator are provided between the respective loads and the respective distribution lines via a power transmission circuit breaker. Connected in series with each other and provided corresponding to the load connected to each of the distribution lines,
The AC power of a distributed power source obtained from a system interconnection converter that converts DC power from a DC power source into AC power or a generator that generates AC power based on rotational energy from an internal combustion / external combustion engine is connected to the interconnection reactor, respectively. , Configured to supply to each of the distribution lines via a distribution system circuit breaker, input a system voltage detection value and a system current detection value from a system detector provided on the primary side of the interconnection reactor, and A distributed power supply system, comprising: a control device for controlling a power supply;