JP4553206B2 - Distributed power distribution system and distributed power supply - Google Patents

Description

  The present invention relates to a distributed power distribution system and a distributed power supply apparatus.

  In recent years, distributed power sources such as solar power generation, wind power generation, and fuel cell power generation have attracted attention. The electric power generated from these distributed power sources is what is called clean energy or new energy. With the support of the national system, the amount of power generated by distributed power sources will be about 1.18 million kW (kilowatts) for solar power generation in the next few years, about 23 times that for wind power generation. Is expected to increase to 1.34 million kW. And according to the Special Measures Law (RPS Law) regarding the use of new energy by electric power companies, the amount of power generated by new energy (solar power generation, wind power generation, biomass power generation, small and medium hydropower generation, geothermal power generation) in 2010 is It is supposed to increase to 12.2 billion kW, which is about 1.4% of Japan's total power generation of about 871.0 billion kW.

  For such generated power from the distributed power source, a system that is linked to a conventional AC power system (commercial power source) using a synchronous generator is generally employed. In other words, surplus power generated by the distributed power source is sent to the AC power system. In this way, it is possible to effectively use surplus power from the distributed power source. Therefore, if the distributed power source is, for example, by photovoltaic power generation, the DC power obtained by photovoltaic power generation is converted to AC power with the same amplitude and phase as the sine voltage waveform of the AC power system. An inverter for conversion is used. Such an inverter is connected in parallel to the AC power system and the indoor wiring, and sends the surplus power from the distributed power source to the AC power system and supplies power to the electrical equipment that works with AC connected to the indoor wiring. (For example, refer to Patent Document 1).

  According to Patent Document 1, a basic part of a photovoltaic power generation system which is a kind of distributed power source is configured as shown in FIG. Electric power from the solar cell 101 is converted from direct current to alternating current in the inverter 102 and is normally connected to the alternating current power system 110 via the switch 104 that is ON (conducting state). The load 107 is a general household or factory device that is operated by an AC power source. The synchronous follow-up control circuit 111 receives the AC voltage VAC of the AC power system 110 obtained from the instrument transformer PT and the AC current IAC obtained from the instrument current transformer CT as its input signals, and is synchronized with the AC voltage VAC. A required command signal SIN calculated to form a voltage and an alternating current having a power factor of 1 is supplied to the inverter 102. In this way, when the AC power output from the inverter 102 exceeds the amount of power consumed by the load 107, the power is automatically sent to the AC power system 110. Further, when the amount of power consumed by the load 107 is larger than the amount of power supplied by the solar battery 101 that is a distributed power source, power is automatically supplied from the AC power system 110 to the load 107.

  However, the design of such an inverter 102 that produces the same voltage waveform as that of the AC power system 110 has been difficult and expensive. For this reason, a high-performance inverter is not always used. When the amount of power with poor quality sent from the inverter 102 to the AC power system 110 becomes large, a system disturbance (Power) occurs in the AC power system. Disturbance (PD) is caused, and there is a risk that the supply of power from the AC power system may be obstructed. Further, even when the system disturbance does not occur, the waveform distortion of the voltage in the AC power system 110 may occur, and other devices connected to the AC power system 110 may be adversely affected.

  In order to improve such problems, in recent years, the AC power from the AC power system is converted into DC power, and the shortage of power from the distributed power source that generates DC power is constantly being increased by the power from the AC power system. A method of replenishment has been proposed (see, for example, Patent Document 2). In the case of adopting such a method, the surplus DC power from the distributed power source is not sent to the AC power system, so that the problem of the above-mentioned system disturbance and voltage waveform distortion in the AC power system does not occur. .

In addition, electrical equipment that becomes a load, for example, home appliances in general households, and industrial equipment such as electric motors in the factory, in recent years, electronic control by semiconductor devices has been widely adopted, and home appliances It has become a mainstream technology trend to provide a rectifier circuit inside a product or industrial device, and once convert AC power from the AC power system to DC power, and many home appliances already have a DC power supply. It is possible to cope with.
JP-A-10-31525 Japanese Patent Laying-Open No. 2005-229729

  Expectations for distributed power sources are extremely high from the standpoint of maintaining a good global environment, and there is a demand for further development of clean energy development and power supply based on clean energy. However, in the conventional method (see Patent Document 1) in which surplus power generated by the distributed power source is sent to the AC power system every moment (see Patent Document 1), the purpose of compensating the shortage of generated power with the distributed power source can be achieved. However, it is expected that the probability of occurrence of system disturbance and deterioration of power quality (voltage waveform distortion) is extremely high.

  In recent years, a newly proposed system that does not send power generated by a distributed power source back to the AC power system (see Patent Document 2) provides clean energy whose power supply varies with the natural environment. At the same time, since the shortage of demand power is constantly supplemented with the power from the AC power system, the amount of power required for the AC power system will increase over time, after the spread of distributed power sources, It is highly dependent on the change and is expected to change significantly within a day. In that case, the burden of controlling the amount of power generated by the generator of the power plant that sends power to the AC power system is large, and furthermore, the power plant and power transmission facilities must be constructed in accordance with the maximum power demand. Even if the power supply is widely spread, it is expected that the burden on the electric power company will be large. And this burden is feared that it will eventually develop into an energy problem at the national level for consumers who use the power from the AC power system as a price increase in the future.

  Therefore, the present invention solves the above-described problems, makes it possible to adjust the amount of power demand from the AC power system without causing the occurrence of system disturbances and the deterioration of power quality in the AC power system, A distributed power distribution system capable of supplying a load and a distributed power supply suitable for use in the system are provided.

  In order to solve this problem, the distributed power distribution system of the present invention includes a power factor improving rectifier circuit that improves the power factor of AC power from the AC power system, converts the power into DC power, and outputs the DC power. A distributed power source that outputs power, a power switch that selects DC power from the power factor correction rectifier circuit or DC power from the distributed power source, and a capacitor and a load that are connected in parallel to the output side of the power switch And wiring for supplying electric power.

  In the distributed power distribution system having such a configuration, the power factor improving rectifier circuit converts AC power from the AC power system to power factor and converts it into DC power for output, and the distributed power source generates power by itself. Output DC power. In addition, the power switch selects DC power from the power factor correction rectifier circuit or DC power from the distributed power source, and DC is connected to the capacitor connected in parallel to the output side of the power switch and the wiring for supplying power to the load. Supply power. In this way, either the AC power system or the power from the distributed power source is stored in the capacitor, and the DC power can be used via the wiring. In this case, the AC power system and the distributed power supply system are completely separated by the power switch, and no power is exchanged between them. In addition, when DC power from the power factor correction rectifier circuit is not selected by the power switch, power is not supplied from the AC power system.

  In order to solve this problem, another distributed power distribution system according to the present invention includes a power factor improving rectifier circuit that improves the power factor of AC power from an AC power system, converts the power into DC power, and outputs the power factor. A power switch for cutting or conducting DC power from the improved rectifier circuit, a capacitor connected in parallel to the output side of the power switch, a wiring for supplying power to the load, and a distribution for generating DC power and generating DC power itself A mold power source.

  In the distributed power distribution system having such another configuration, the power factor improving rectifier circuit improves the power factor of the AC power from the AC power system, converts it into DC power, and outputs it. In addition, the power switch disconnects or conducts DC power from the power factor correction rectifier circuit. In the case of conduction, the power switch is connected to a capacitor connected in parallel to the output side of the power switch and wiring for supplying power to the load. Supply DC power. The distributed power source is also connected in parallel to the output side of the power switch, and the direct-current power generated by itself and the direct-current power from the power factor correction rectifier circuit are equally distributed and supplied to the capacitor and the load. Further, when the DC power from the power factor correction rectifier circuit is cut by the power switch, the power is not supplied from the AC power system.

  In order to solve such a problem, the distributed power supply apparatus of the present invention improves the power factor of AC power from the AC power system, converts it into DC power and outputs it, and generates power by itself. A distributed power source that outputs DC power, a power switch that selects DC power from the power factor improving rectifier circuit or DC power from the distributed power source, and a capacitor and power connected in parallel to the output side of the power switch And an output terminal.

  In the distributed power supply apparatus having such a configuration, the power factor improving rectifier circuit converts the AC power from the AC power system to power factor and converts it into DC power for output, and the distributed power source generates power by itself. Outputs DC power. The power switch selects DC power from the power factor correction rectifier circuit or DC power from the distributed power source, and supplies DC power to a capacitor and a power output terminal connected in parallel to the output side of the power switch. In this way, either the AC power system or the power from the distributed power source is stored in the battery, and the DC power can be used via the power output terminal. In this case, the AC power system and the distributed power supply system are completely separated by the power switch, and no power is exchanged between them. In addition, when DC power from the power factor correction rectifier circuit is not selected by the power switch, power is not supplied from the AC power system.

  In order to solve such a problem, another distributed power supply apparatus of the present invention includes a power factor improving rectifier circuit that improves the power factor of AC power from an AC power system, converts the power into DC power, and outputs the power. A power switch for cutting or conducting DC power from the rate improving rectifier circuit; a capacitor connected in parallel to the output side of the power switch; a distributed power source that generates power and outputs DC power; and a power output terminal. I decided to prepare.

  In the distributed power distribution device having such another configuration, the power factor correction rectifier circuit improves the power factor of the AC power from the AC power system, converts it into DC power, and outputs it. The power switch disconnects or conducts DC power from the power factor correction rectifier circuit, and in the case of conduction, supplies DC power to a capacitor and a power output terminal connected in parallel to the output side of the power switch. The distributed power source is also connected in parallel to the output side of the power switch, and the direct-current power generated by itself and the direct-current power from the power factor correction rectifier circuit are apportioned and supplied to the capacitor and the power output terminal. In addition, when DC power from the power factor correction rectifier circuit is not selected by the power switch, power is not supplied from the AC power system.

  According to the present invention, a distributed power source that can adjust the amount of power demand from an AC power system and supply DC power to a load without causing the occurrence of system disturbances and the deterioration of power quality in the AC power system. A power distribution system and a distributed power supply suitable for use in the power distribution system can be provided.

  (Distributed power distribution system of the first embodiment)

  A distributed power distribution system 51 according to the first embodiment will be described with reference to FIG. It is assumed that the power from the AC power system 4 is a single-phase 100 V (volt), 50 Hz (Hertz) commercial power, and the voltage in the DC power unit including the indoor wiring 8 is 200 V DC. explain. Accordingly, the wiring from the AC power system 4 in FIG. 1 and all the wirings after conversion to DC power are connected by two lines, but for simplicity of description, they are described by one line in FIG. .

  The distributed power distribution system 51 includes a distributed power supply device 50 and an indoor wiring 8. The distributed power supply device 50 includes a power factor improving rectifier circuit 6 that converts power from the AC power system 4 input via the circuit breaker 5 to DC power by improving the power factor, and generates DC power by generating power by itself. Distributed power source 1, power switch 7 for selecting either DC power from power factor correction rectifier circuit 6 or DC power from distributed power source 1, and a battery connected in parallel to the output side of power switch 7 3, a power output terminal 10, and a power supply control unit 2 that controls the power switch 7. The indoor wiring 8 is connected to the power output terminal 10 of the distributed power supply device 50 so that power can be supplied to one or a plurality of loads.

  The circuit breaker 5 is a member for safety measures that receives power from the AC power system 4 and cuts off when the amount of current passing through the circuit breaker 5 exceeds a specified value. It is a conventionally used member. The power factor improving rectifier circuit 6 performs a rectifying operation for converting AC power into DC power, and at this time, performs a power factor improving operation with a power factor of 1. The distributed power source 1 is a power generation device that generates power by itself, for example, a solar power generation device, a wind power generation device, a biomass power generation device, a small / medium hydropower generation device, a geothermal power generation device, or the like, or any combination thereof. It is. The power switch 7 is a relay or a semiconductor electronic switch element having a mechanical contact. The capacitor 3 is, for example, a lead storage battery or an electric double layer capacitor. The power supply control unit 2 has a calculation function, a determination function, and a function for controlling the power switch 7, and mainly includes any one of a DSP (Digital Signal Processor), a hardware logic circuit, a FPGA (Field Programmable Gate Array), and the like. It is an element. The indoor wiring 8 is a conventional wiring in the same site. The end of the indoor wiring 8 has an outlet (not shown), and the load is an illuminator 11, an air conditioner (air conditioner) 12, a refrigerator 13, a washing machine 14, and a television receiver (TV). Power is supplied to these devices via respective plugs (not shown) such as 15, other (other electrical products) 16 and the like.

  The current Ib2 from the power factor correction rectifier circuit 6 and the current Ib1 from the distributed power source 1 are switched by the power switch 7 and flow into the capacitor 3 and the power output terminal 10. In the first embodiment, the power switch 7 is an ON / OFF switch with one circuit and two contacts, and any one of the two contacts, the contact Sw1 or the contact Sw2, is set as the contact Swc by the control signal Sws from the power supply control unit 2. It is switched whether it is connected to the battery 3 and the power output terminal 10 via. That is, the distributed power supply voltage information Svg corresponding to the distributed power supply output voltage Vgo from the distributed power supply 1 is input to the power supply control unit 2, and the control signal Sws is output based on the distributed power supply voltage information Svg. . The main part in 1st Embodiment is demonstrated in detail below.

(Distributed power supply)
The distributed power source 1 will be described with reference to FIG. The distributed power source 1 includes a power generation unit 21 and a backflow prevention diode 22. The power generation unit 21 may be any of a solar power generation device, a wind power generation device, a biomass power generation device, a small / medium hydropower generation device, a geothermal power generation device, and the like. Each of these devices generates direct-current power, and is characterized in that the amount of generated power is greatly influenced by the natural environment. For example, in a wind turbine generator, when a DC motor is used for the power generation mechanism, the magnitude of the generated voltage Vg depends on the number of rotations of the wind turbine that receives wind power. Therefore, when the power generation unit 21 is directly connected to the battery 3, if the rotation speed of the windmill is low, the power from the battery 3 flows back to the power generation unit 21, so that the backflow prevention diode 22 is used to prevent this. When the power generated by the power generation unit 21 is not sufficient, the backflow prevention diode 22 is turned off (cut). Then, when the generated power of the power generation unit 21 is sufficient, the backflow prevention diode 22 is turned on (conductive), a charging current is supplied to the battery 3 according to the generated power, and power is supplied to the indoor wiring 8. Here, when the specified voltage of the capacitor 3 is 200 V, the distributed power supply output voltage obtained by subtracting the forward voltage Vd22 from the forward voltage Vd22 of the backflow prevention diode 22 and the generated voltage Vg of the power generation unit 21. When the value of Vgo exceeds 200V, the backflow prevention diode 22 is turned on. The resistors R1 and R2 form a voltage divider for outputting distributed power supply voltage information Svg, which will be described later.

(Power factor correction rectifier circuit)
The power factor improving rectifier circuit 6 maintains a power factor at a power load input to the distributed power distribution system 51 from the AC power system 4 and supplies a predetermined DC voltage Vb to the indoor wiring 8 and the capacitor 3. It is. By setting the power factor to 1, when viewed from the AC power system 4, the distributed power distribution system 51 can be regarded as a pure resistance load, no reactive power is generated, and the influence on the AC power system 4 is the least moderate. Can be. In order to set the power factor to 1, the waveform of the AC voltage VAC in the AC power system 4 and the waveform of the AC current IAC flowing from the AC power system 4 into the distributed power distribution system 51 may be similar.

  An example of the power factor correction rectifier circuit 6 will be described with reference to FIG. The power factor correction rectifier circuit 6 includes a full-wave rectifier circuit 25, an inductor 26, a switch element 27, a diode 28, a capacitor 29, a power factor improvement circuit control unit 30, an instrument current transformer 31, a voltage divider 33 and a voltage divider 34. Prepare. In the full-wave rectifier circuit 25, rectifier diodes Di1 to Di4 are bridge-connected. A connection point between the rectifier diode Di1 and the rectifier diode Di4 and a connection point between the rectifier diode Di2 and the rectifier diode Di3 are connected to the circuit breaker 5 as input sides. Further, a connection point between the rectifier diode Di1 and the rectifier diode Di3 and a connection point between the rectifier diode Di2 and the rectifier diode Di4 are respectively connected to the inductor 26 and the switch element 27 as output sides. The inductor 26, the switch element 27, the diode 28, and the capacitor 29 constitute a so-called step-up switching regulator. Here, in this embodiment, a MOS-FET (Metal Oxide Semiconductor Field Effect Transistor) is used as the switch element 27. The power factor correction circuit control unit 30 is an arithmetic circuit for outputting a gate control signal Src for controlling the gate of the MOS-FET. In this embodiment, a DSP is used, and the current transformer for the instrument is used. Based on the signal Siri from the voltage divider 31, the signal Svri from the voltage divider 33, and the signal Svro from the voltage divider 34, the DSP calculates the gate control signal Src.

  The operation of the power factor correction rectifier circuit 6 will be briefly described with reference to the waveforms of the respective parts shown in FIG. An AC voltage VAC (see FIG. 4A) from the AC power system 4 is applied to the full-wave rectifier circuit 25 via the circuit breaker 5. The full-wave rectification circuit 25 outputs a 100-Hz rectified output voltage Vri that has been full-wave rectified (see FIG. 4B). The switch element 27 repeats ON and OFF alternately based on the gate control signal Src (see FIG. 4D). In FIG. 4, for ease of explanation, the cycle of ON and OFF is described as about 1/8 times 10 mSec, but is actually about 1/1000. When the switch element 27 is ON, an inductance current Iri is supplied so as to store energy in the inductor 26. When the switch element 27 is OFF, energy is released from the inductor 26 and the capacitor 29 is charged. Inductance current Iri is supplied so as to supply (see FIG. 4C). The broken line in FIG. 4C is an envelope of the peak value of the inductance current Iri for each period, and the power factor correction circuit control unit is configured so that the envelope of the inductance current Iri is similar to the rectified output voltage Vri. 30 and the value of the rectifier circuit output voltage Vro (see FIG. 4E) is also controlled to be a slightly high predetermined voltage in the vicinity of 200V.

  A control operation performed by the power factor correction circuit control unit 30 will be briefly described. The power factor correction circuit control unit 30 includes a PWM (Pulse Width Modulation) modulator, an error amplifier, and a reference signal generator (not shown) serving as a target value. In the present embodiment in which the power factor correction circuit control unit 30 includes a DSP as a main part, these various functions are realized as software processed by the DSP. The power factor correction circuit control unit 30 includes two feedback servo systems. The first feedback servo system is for setting the rectifier circuit output voltage Vro to a predetermined value, and the second feedback servo system is an envelope of the rectified output voltage Vri and the inductance current Iri (proportional to the average current). ) Is a similar shape.

  First, an error signal obtained by amplifying the difference between the value of the signal Svro from the voltage divider 34 and the reference value from the reference signal generator by an error amplifier is detected. Then, a product signal that is a product of the value of the signal Svri from the voltage divider 33 and the error signal is calculated. Then, until the inductance current Iri reaches the value of the product signal, the gate control signal Src is set to the high level and the switch element 27 formed by the N-channel MOS-FET is turned on. At this time, magnetic energy is stored in the inductor 26. When the inductance current Iri reaches the value of the product signal, the gate control signal Src is set to the low level, and the switch element 27 formed by the N-channel MOS-FET is turned OFF. At this time, the magnetic energy stored in the inductor 26 is released to charge the capacitor 29. When the inductance current Iri reaches zero, the gate control signal Src is set to the high level again, and the switch element 27 formed by the N-channel MOS-FET is turned on. The DC power having the power factor improved by repeating the above is obtained from the power factor improving rectifier circuit 6. A line filter (not shown) is provided on the input side of the AC power system 4 and the power factor improving rectifier circuit 6 so that switching noise generated when the switching element 27 performs high-frequency switching does not leak to the AC power system 4. Is inserted between.

  The reason why the value of the rectifier circuit output voltage Vro is set to a voltage slightly higher than the rated voltage of the capacitor 3 near 200 V is that, in this way, a substantially constant voltage can be supplied to the indoor wiring 8 and the capacitor When 3 is a lead-acid battery, the magnitude of the charging current is determined according to this slightly increased voltage, for example, a voltage within several volts, so that the power is selected according to the selection of the value of the rectifier circuit output voltage Vro. The magnitude of the charging current supplied from the rate improvement rectifier circuit 6 to the battery 3 can be determined.

(Power switch)
The power switch 7 can be formed of a mechanical relay. In this case, however, the possibility of causing arc discharge at the contact point is very high in order to switch the direct current path. Therefore, in the present embodiment, an electronic power switch composed of an N-channel MOS-FET is used.

  The power switch 7 will be described with reference to FIG. The power switch 7 is composed of an N-channel MOS-FET 41, an N-channel MOS-FET 42, and an inverter 43. The drain of the N-channel MOS-FET 41 corresponds to the contact Sw1 in FIG. The drain corresponds to the contact Sw2 in FIG. 1, and the connection point of each source of the N-channel MOS-FET 41 and the N-channel MOS-FET 42 corresponds to the contact Swc in FIG. The control signal Sws is directly input to the gate of the N channel MOS-FET 41, and the control signal Sws inverted by the inverter 43 is input to the gate of the N channel MOS-FET 42. In such an electronic switch, when the control signal Sws is at a high level, the contact Sw1 and the contact Swc (between the drain and the source of the N-channel MOS-FET 41) are conducted, and the control signal Sws is at a low level. In this case, the contact Sw2 and the contact Swc (between the drain and the source of the N-channel MOS-FET 42) are conducted. The diode between the drain and the source of each of the N-channel MOS-FET 41 and the N-channel MOS-FET 42 is a parasitic diode (body diode), and is usually formed unintentionally in the process of manufacturing the MOS-FET. It is an element.

(Power control unit)
Based on the configuration of each unit described above, how the entire distributed power distribution system 51 operates will be described focusing on the operation of the power control unit 2. The power supply control unit 2 includes a CPU (Central Processing Unit) and a MEM (Memory) (both not shown) as main parts. Control is performed by the CPU sequentially processing software stored in the MEM for controlling the distributed power distribution system 51. Interrupt processing every predetermined time is the main routine of processing, and the main part of the processing procedure is shown below.

Using the interrupt signal from the interrupt timer as a trigger, the value of the distributed power supply voltage information Svg is read (step ST001).
Next, it is determined whether the distributed power supply voltage information Svg is greater than or equal to a predetermined value (step ST002).
Here, the magnitude of the predetermined value Ref1 is expressed by (Expression 1). D1 is the value of the voltage dividing ratio (R1 / (R1 + R2)) of the voltage divider. Further, α is a value of the accumulated voltage required to charge the battery 3 when the voltage of the indoor wiring 8 is 200 V, and is a constant within a range of several volts. Vd22 is the value of the forward voltage of the backflow prevention diode 22, and the value of Vd22 increases as the current increases. Therefore, in the present embodiment, there is also an action of preventing the charging current from flowing excessively.
(Formula 1)
Ref1 = (200 + α−Vd22) × D1
If the distributed power supply voltage information Svg is greater than or equal to the predetermined value, the process proceeds to step ST003, and if the distributed power supply voltage information Svg is less than the predetermined value Ref1, the process proceeds to step ST005.

In step ST003, it is determined whether Yes in step ST002 is continuously N times or more or less than N times.
If it is N times or more (Yes), the control signal Sws is set to the high level (step ST004), then the number n is reset (step ST007), and the process returns to step ST001 again.
If it is less than N times (No), the control signal Sws is left as it is, and the process returns to step ST001 again.
Here, the number of times N is set to prevent the power switch 7 from being frequently switched in accordance with fluctuations in the amount of power generated by natural energy and the amount of power consumed by the load. Here, the numerical value N can be set corresponding to a range of several seconds to several tens of hours. The longer the numerical value N is, the more the distributed mode is changed from the DC power supply mode from the power factor correction rectifier circuit 6. The time until returning to the DC power supply mode from the power source 1 can be set longer.

On the other hand, in step ST005, it is determined whether the determination of No in step ST002 is continuously M times or more or less than M times.
If it is M times or more (Yes), the control signal Sws is set to the low level (step ST006), then the number n is reset (step ST008), and the process returns to step ST001 again.
When it is less than M times (No), the control signal Sws is left as it is, and the process returns to step ST001 again. Here, the M number of times is set in order to prevent the power switch 7 from being frequently switched due to fluctuations in the amount of power generated by natural energy and the amount of power consumed by the load. Here, the numerical value M can be set in correspondence with the range of several seconds to several tens of hours. The longer the numerical value M, the more the direct current power supply mode 4 from the DC power supply mode becomes. Can be set to a long time until the DC power supply mode is restored through the power factor correction rectifier circuit 6.

  With the above processing, when the distributed power supply voltage information Svg is less than the predetermined value Ref1, that is, when the distributed power supply 1 cannot generate enough power to charge the battery 3, the maximum time is determined by the numerical value M. During the predetermined time, after the DC power from the battery 3 is supplied to the load via the indoor wiring 8, the DC power is supplied from the power factor correction rectifier circuit 6 to charge the battery 3 and via the indoor wiring 8. It is possible to supply DC power having an appropriate voltage of around 200 V to various loads to be connected. That is, depending on what value is set to the numerical value M and the numerical value N, the time required for returning from the DC power supply mode from the power factor correction rectifier circuit 6 to the DC power supply mode from the distributed power supply 1 is determined. Can be set. In addition, the time setting from when the DC power supply mode from the distributed power source 1 is restored to the DC power supply mode from the power factor correction rectifier circuit 6 is set. When the DC power from the distributed power source 1 decreases for a long time, the power is not supplied from the distributed power source 1 or the power factor improving rectifier circuit 6 and the power is supplied from the capacitor 3 to the indoor wiring 8. Can also be set.

  In this case, DC power is supplied from the power factor correction rectifier circuit 6 to various loads connected via the capacitor 3 and the indoor wiring 8, but is not supplied to the distributed power source 1, and similarly, The DC power from the distributed power source 1 is supplied to various loads connected via the capacitor 3 and the indoor wiring 8, but is not supplied to the power factor correction rectifier circuit 6. That is, since there is no power supplied from the distributed power source 1 to the AC power system 4, it is connected to a synchronous generator (not shown) of a power plant that supplies power to the AC power system 4 or to this AC power system 4. The other power devices are not adversely affected by system disturbance, increased loss due to voltage waveform distortion, and other malfunctions caused by voltage waveform distortion. Also, many home appliances or industrial equipment that operate with power from the AC power system have a rectifier circuit inside, so when rectifying the power from the AC power system, the diode of the rectifier circuit causes unwanted electromagnetic interference. However, when DC power is supplied in this way, switching noise does not occur. Furthermore, by appropriately selecting the value M, the AC power system 4 and the distributed power distribution system 51 are appropriately connected, and the influence on the AC power system 4 can be reduced. Furthermore, if a communication function with the AC power system 4 to be described later is used to inform the start time of power consumption from the planned AC power system 4 based on the value of the numerical value M, the influence on the AC power system 4 is further affected. Can be less.

(Distributed Power Distribution System of Second Embodiment)
In the distributed power distribution system 51 of the first embodiment described above, the power switch 7 is a switch of one circuit and two contacts (Sw1, Sw2, Swc), and the power supply control unit 2 is connected to the direct current from the power factor correction rectifier circuit 6. The storage battery is configured to supply DC power to the battery 3 or the indoor wiring 8 from only one of the power and the DC power from the distributed power supply 1 or without supplying power from both by the action of the backflow prevention diode 22. 3, the power switch 7 is controlled so as to be supplied to the indoor wiring 8. However, in the distributed power distribution system 61 of the second embodiment shown in FIG. 7, the distributed power supply 1 is always connected to the capacitor 3 and the indoor wiring 8. The power supply control unit 2 is configured such that the DC power corresponding to the amount of power generated by the distributed power source 1 and the DC power from the power factor correction rectifier circuit 6 generated by the distributed power source 1 Controlling the power switch 67 to supply the capacitor 3, or interior wiring 8. Parts having the same configuration and operation as in the first embodiment are denoted by the same reference numerals as those in the first embodiment, and description thereof is omitted. Hereinafter, the distributed power distribution system 61 and the distributed power supply device 60 of the second embodiment will be described in more detail.

  The power switch 67 is a 1-circuit 1-contact (Sw2, Swc) switch, and has the same configuration as that in which the N-channel MOS-FET 41 is not provided in FIG. The ON / OFF of the contact point Sw2 and the contact point Swc is controlled by the control signal Sws. The specific control in the power supply control unit 2 is performed as follows. When the distributed power supply voltage information Svg is equal to or greater than the predetermined value Ref1 expressed by (Expression 1), the contact Sw2 and the contact Swc are turned OFF, and the distributed power supply voltage information Svg is expressed by (Expression 1). When the value is less than the predetermined value Ref1 represented by, the contact Sw2 and the contact Swc are turned ON. Further, similarly to the first embodiment, it is also possible to delay the switch ON timing using the numerical value M, and to delay the switch OFF timing using the numerical value N.

  In this manner, when the distributed power supply voltage information Svg is less than the predetermined value Ref1, that is, when the distributed power supply 1 cannot generate enough power to charge the battery 3, the power factor correction rectifier circuit 6 DC power is supplied to charge the battery 3 and to supply various loads connected via the indoor wiring 8 with appropriate voltage DC power around 200V.

  In this case, the DC power is supplied from the power factor correction rectifier circuit 6 to various loads connected via the battery 3 and the indoor wiring 8, but is not supplied to the distributed power source 1. Similarly, DC power from the distributed power source 1 is supplied to various loads connected via the capacitor 3 and the indoor wiring 8, but is not supplied to the power factor correction rectifier circuit 6. That is, since there is no power supplied from the distributed power source 1 to the AC power system 4, a synchronous generator of a power plant that supplies power to the AC power system 4 or other power connected to the AC power system 4 It does not adversely affect the equipment due to system disturbance, increased loss due to voltage waveform distortion, and other malfunctions caused by voltage waveform distortion.

(Distributed power distribution system of the third embodiment)
In the distributed power distribution system 51 of the first embodiment described above, the power switch 7 is provided, and in the distributed power distribution system 61 of the second embodiment described above, the power switch 67 is provided to perform power switching. It is not always necessary to configure the power switch as an independent component. That is, the backflow prevention diode 22 in FIG. 2 and the diode 28 in FIG. 3 can be used as power switches. By such a power switch, the ratio of the passing power amount between the DC power from the power factor correction rectifier circuit 6 and the DC power from the distributed power source 1 is controlled. Hereinafter, the distributed power distribution system 71 and the distributed power supply 70 according to the third embodiment will be described with reference to FIG. 8. However, the same configuration and operation as those in the first embodiment are described in the first embodiment. The same reference numerals are used and the description thereof is omitted.

  First, the case where the power generation amount of the distributed power source 1 shown in FIG. 2 is large will be described with reference to FIG. In this case, the voltage value of the distributed power supply output voltage Vgo (see FIG. 2) becomes high, and when the battery 3 is a lead storage battery, a large charging current flows to the battery 3 and the voltage value of the battery 3 Rises slightly, and the value of the voltage supplied to the indoor wiring 8 also rises with it. In this case, the voltage value of the rectifier circuit output voltage Vro (see FIG. 3) is lower than the voltage value of the distributed power supply output voltage Vgo. As a result of the action of the feedback servo system that the power factor correction circuit control unit 30 forms part of, the time ratio of the gate control signal Src automatically becomes zero, the diode 28 is turned OFF, and passes through the diode 28. The passing electric energy is zero.

  Next, the case where the power generation amount of the distributed power source 1 is small will be described. In this case, the value of the distributed power supply output voltage Vgo is low. Then, the value of the distributed power supply output voltage Vgo becomes lower than the value of the DC voltage Vb of the battery 3 (which is also the voltage supplied to the indoor wiring 8), the backflow prevention diode 22 is turned OFF, The amount of power passing through the backflow prevention diode 22 is zero. In this case, electric power is supplied only from the power factor correction rectifier circuit 6.

  According to the third embodiment, the backflow prevention diode 22 and the diode 28 have the same function as that of the power switch 7 or the power switch 67 described above, and are distributed according to the amount of generated power from the distributed power source 1. It is switched whether DC power is supplied from the mold power source 1 or DC power is supplied from the power factor correction rectifier circuit 6. However, in this state, there is no function for delaying the switching timing. Therefore, the power factor correction circuit control unit 30 is provided with a timer function, and once the supply of power from the distributed power source 1 starts, the supply of DC power from the power factor correction rectifier circuit 6 does not start until after a predetermined time. It can also be done. In any case, the synchronous generator of the power station that supplies power to the AC power system 4 or other power equipment connected to the AC power system 4 has a system disturbance, increased loss due to voltage waveform distortion, and other voltage waveforms. There is no adverse effect of malfunction due to distortion.

(Another embodiment of distributed power supply)
A part of various modifications of the first to third embodiments described above will be described below. In the above-described first embodiment, the backflow prevention diode 22 is used to prevent the backflow of current to the distributed power source 1, but the current transformer CT or the current detection resistor is not used without using the backflow prevention diode 22. (Neither of which is shown) is used to monitor the input / output current to / from the distributed power supply 1, and the input / output current signal corresponding to the input / output current is used instead of the distributed power supply voltage information Svg. When the signal detects a backflow current from the capacitor 3 to the distributed power source 1, the power switch 7 can also be controlled to turn off the N-channel MOS-FET 41.

  Further, the power switch 7 has been described as a switch of 1 circuit 2 contacts (Sw1, Sw2, Swc) or 1 circuit 1 contact (Sw1, Swc). However, in the switch of 1 circuit 2 contacts, the contact Sw1 or the contact Sw2 It is good also as what the contact point Swc does not contact any of these. In this case, all DC power from the power output terminal 10 is output from the battery 3, and even when the power generation amount from the distributed power source 1 is small, the power factor correction rectifier circuit 6 does not necessarily take power. As a result, the load on the AC power system 4 can be reduced.

  Further, in the first to third embodiments described above, the power generated from the distributed power source 1 is supplied to the battery 3 and the indoor wiring 8 via the backflow prevention diode 22 without being processed. When an electric double layer capacitor is used as the capacitor 3, the voltage supplied to the indoor wiring 8 may not be determined. Further, when the generated voltage from the distributed power source 1 is lower than around 200 V, which is the specified voltage of the indoor wiring 8, the generated power from the distributed power source 1 is not used at all. In order to avoid such a situation, it is desirable to place a DC-DC converter unit (not shown) between the power generation unit 21 of the distributed power source 1 and the battery 3. By adopting such a configuration, the output voltage of the DC-DC converter unit can be set to an arbitrary value, so that the output voltage from the distributed power source 1 can always be set to a voltage around 200V. By adopting such a configuration, the generated power from the distributed power source 1 can be used effectively, and the voltage supplied from the indoor wiring 8 is set to a predetermined voltage even when the battery 3 is an electric double layer capacitor. Can do.

  In addition, a step-up type switching regulator is used as the power factor correction rectifier circuit 6, but when the specified voltage in the indoor wiring 8 is made lower than the peak voltage value of the AC voltage VAC from the AC power system 4, a step is used. A power factor improving rectifier circuit can be configured by a down type switching regulator (not shown). Furthermore, an inductance having a sufficient power factor improvement effect for 50 Hz is inserted on the AC input side, and the power factor is improved by reducing the inrush current near the voltage peak of the capacitor input type rectifier circuit. Also good.

  Further, in the configuration as shown in FIG. 9, the distributed power supply 80 and the distributed power supply 91 constituting the distributed power distribution system 81 are provided with the above-described DC-DC converter, and the charging current flowing through the capacitor 3 The distributed power supply output voltage Vgo (see FIG. 2) may be controlled by the signal Ssb so that the signal Sib corresponding to the signal Sb is detected and the charging current becomes a predetermined value. Further, the signal Sib corresponding to the charging current flowing through the battery 3 is detected, and the rectifier circuit output voltage Vro of the power factor correction rectifier circuit 86 is determined by the signal Scd so that the charging current becomes a predetermined value (see FIG. 3). May be controlled. In this way, a stable charging current can be supplied to the storage battery 3 such as a lead storage battery, the voltage Vb of the storage battery can be stabilized, and a stable voltage can be supplied to the indoor wiring 8.

  Furthermore, the signal Spb corresponding to the specific gravity of the electrolyte of the lead storage battery or the value of the DC voltage Vb of the battery 3 is detected to estimate the accumulated power amount, and the distributed power source 91 is determined according to the estimated accumulated power amount. The distributed power supply output voltage Vgo may be controlled by the signal Scb, or the rectifier circuit output voltage Vro of the power factor correction rectifier circuit 86 may be controlled by the signal Scd. The signal Scb and the signal Scd are output from the control unit with communication function 82 shown in FIG.

  In addition, in order to charge the battery 3 using the relatively inexpensive midnight power for the average use of the generated power in the power station that supplies power to the AC power system 4, the power switches of the various aspects described above are used. Thus, for example, the DC power from the power factor correction rectifier circuit may be controlled to be conducted at a predetermined time at midnight.

  Furthermore, the control unit with communication function 82 informs the power plant that supplies power to the AC power system 4 of the status of each distributed power distribution system as a demand forecast, and manages the generated power at the power plant. It may be made possible. The demand forecast to inform the power plant is a power generation forecast amount based on the power consumption amount of the load connected to the indoor wiring 8, the power supply amount from the distributed power source 91, the nature of the distributed power source 91 (for example, tomorrow's wind power) , Hours of sunshine, etc.), power supplied from the power factor correction rectifier circuit 86, the amount of power stored in the current battery 3, and the like.

1 is a configuration diagram of a distributed power distribution system according to a first embodiment. FIG. It is a block diagram of the distributed power supply of embodiment. It is a block diagram of the power factor improvement rectifier circuit of embodiment. It is a figure explaining the principle of operation of the power factor improvement rectifier circuit of an embodiment. It is a block diagram of the power switch of the embodiment. It is a flowchart of operation | movement of the distributed power distribution system of 1st Embodiment. It is a block diagram of the distributed power distribution system of 2nd Embodiment. It is a block diagram of the distributed power distribution system of 3rd Embodiment. It is a block diagram of the distributed power distribution system of other embodiment. It is a figure explaining background art.

Explanation of symbols

1, 91 Distributed type power source, 2 Power source control unit, 3 Power storage, 4 AC power system, 5 Circuit breaker, 6, 86 Power factor improving rectifier circuit, 7, 67 Power switch, 8 Indoor wiring, 10 Power output terminal, 11 Illumination 13 refrigerator, 14 washing machine, 21 power generation unit, 22 backflow prevention diode, 25 full-wave rectifier circuit, 26 inductor, 27 switch element, 28 diode, 29 capacitor, 30 power factor improvement circuit control unit, 31 current transformer for instrument , 33 voltage divider, 34 voltage divider, 43 inverter, 50, 60, 70, 80 distributed power supply, 51, 61, 71, 81 distributed power distribution system, 82 control unit with communication function

Claims (5)

A power factor improving rectifier circuit that improves the power factor of the AC power from the AC power system, converts it into DC power, and outputs it;
A distributed power source that generates its own power and outputs DC power;
A power switch for selecting DC power from the power factor improving rectifier circuit or DC power from the distributed power source;
A capacitor connected in parallel to the output side of the power switch and wiring for supplying power to the load;
A communication function for the AC power system,
The power switch is
When the voltage generated from the distributed power source is equal to or higher than a predetermined voltage for a first predetermined time or more, the direct current power from the distributed power source is selected instead of the direct current power from the power factor correction rectifier circuit and the battery And controlled to supply the wiring,
When the voltage generated by the distributed power source is less than the predetermined voltage over a second predetermined time, the DC power from the power factor improving rectifier circuit is selected instead of the DC power from the distributed power source, and Controlled to supply the capacitor and the wiring,
By the communication function, based on the second predetermined time, to notify the start time of power consumption from the scheduled AC power system,
Distributed power distribution system. The distributed power distribution system according to claim 1, wherein the power switch is controlled to select DC power from the power factor correction rectifier circuit at a predetermined time. A power factor improving rectifier circuit that improves the power factor of the AC power from the AC power system, converts it into DC power, and outputs it;
A distributed power source that generates its own power and outputs DC power;
A power switch for selecting DC power from the power factor improving rectifier circuit or DC power from the distributed power source;
A capacitor and a power output terminal connected in parallel to the output side of the power switch;
A communication function for the AC power system,
The power switch is
When the voltage generated from the distributed power source is equal to or higher than a predetermined voltage for a first predetermined time or more, the direct current power from the distributed power source is selected instead of the direct current power from the power factor correction rectifier circuit and the battery And controlled to supply to the power output terminal,
When the voltage generated by the distributed power source is less than the predetermined voltage over a second predetermined time, the DC power from the power factor improving rectifier circuit is selected instead of the DC power from the distributed power source, and Controlled to supply a capacitor and the power output terminal,
By the communication function, based on the second predetermined time, to notify the start time of power consumption from the scheduled AC power system,
Distributed power supply. The power switch has a first MOS-FET having one end connected to the power factor improving rectifier circuit and a second MOS-FET having one end connected to the distributed power source, The distributed power distribution system according to claim 1 or 2, wherein the other end and the other end of the second MOS-FET are connected to each other . The power switch has a first MOS-FET having one end connected to the power factor improving rectifier circuit and a second MOS-FET having one end connected to the distributed power source, 4. The distributed power supply device according to claim 3, wherein the other end and the other end of the second MOS-FET are connected to each other .

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