JP2001275258A - Solar battery system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To supply necessary power to a compressor irrespective of generated power of a solar battery depending on the quantity of solar radiation, and reduce the running cost of a commercial power. SOLUTION: This battery system is provided with the solar battery 1 and the commercial power source 3, and operates a compressor 2 by supplying the commercial power equivalent to insufficient part of generated power of the solar battery. That is, the generated power of the solar battery and power which has passed an AC/DC converting circuit 10 from the commercial power are supplied to an inverter 6, and the compressor is operated by AC output of the inverter. An output voltage of the inverter is set as a value lower than the peak voltage when the compressor is operated only by the generated power of the solar battery in the case of a clear sky. When the generated power of the solar battery decreases, power supply from the AC/DC converting circuit, i.e., the commercial power increases. A controller 9 switches over cleaning operation and reverse cleaning operation, and supplies large power to the compressor in the case of reverse cleaning.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solar cell system using a solar cell and a commercial power supply in combination, and more particularly, to a water quality for effectively operating the power generated by the solar cell and reducing the running cost of the commercial power supply to perform a compressor operation. It relates to a purification device.

[0002]

2. Description of the Related Art In recent years, water purification devices have been actively used in factories, water and sewage facilities, rivers, and the like due to increasing concerns about environmental problems. The water purification device is driven by a pump, but usually uses a solar cell to operate the compressor for energy saving. For example, Japanese Patent Application Laid-Open No. H08-118041 discloses a water purification device that operates a compressor according to the power generated by a solar cell.

[0003]

However, in the prior art as described above, the compressor cannot be operated on a cloudy day or a rainy day with a small amount of solar radiation because the solar cell cannot be used. Therefore, the operation time is limited, and the necessary operation cannot be secured when necessary. Incidentally, there is a method of switching between a solar cell and a commercial power supply in order to secure operation when necessary. However, in such an alternative switching method, for example, when switching to a commercial power supply when the amount of power generation is small, such as when it is cloudy, the power generated by the solar cell is not used at all and the energy of the solar cell is wasted. At the same time, commercial power is wasted. Also,
In order to use the solar cell effectively even in cloudy weather, if the power supply from the solar cell is set lower and switched to commercial power, when the water purification device is backwashed,
The compressor cannot supply the required power. That is, at the time of the backwashing, the backwashing effect becomes insufficient with the same amount of air as during the purification operation. Therefore, it is necessary to operate the compressor with large electric power. However, such a large electric power cannot be supplied from the solar cell when it is cloudy.

The present invention has been made in view of such circumstances, and an object of the present invention is to always generate electric power required by a compressor regardless of the amount of generated power of a solar cell depending on the amount of solar radiation. An object of the present invention is to provide a solar cell system provided with a power supply system capable of supplying power and reducing the running cost of a commercial power supply.

[0005]

In order to solve the above-mentioned problems, a solar cell system according to the present invention is a solar cell system in which a solar cell and a commercial power supply or a storage battery are used to operate a compressor. The compressor is operated by supplying electric power from a commercial power supply to the extent that the electric power is insufficient. In other words, if a commercial power supply can be used for the shortage of the power generated by the solar cell, a necessary operation amount can always be secured. Further, in order not to waste the power generated by the solar cell, an AC / DC conversion circuit is provided at the output stage of the commercial power supply, so that the solar cell and the commercial power supply can be used together. further,
To make sure you get the power you need when you need it,
A function of arbitrarily changing the voltage value is provided in the output voltage setting portion of the AC / DC conversion circuit.

In this manner, when a large amount of air is required at the time of back washing, the maximum power can be supplied from the AC / DC conversion circuit, and when the water temperature is low, the power supplied from the commercial power supply can be reduced to a low level. To lower the running cost and raise the supply level if you want to concentrate on driving.

That is, in the solar cell system according to the first aspect of the present invention, in a solar cell system in which a compressor is operated by using a solar cell and a commercial power supply or a storage battery together, the voltage value of the commercial power supply or the storage battery is arbitrary. A voltage control means for setting the value of the voltage, a drive voltage generation means for generating a drive voltage for the compressor using the output voltages of the solar cell and the voltage control means, and a voltage set by the voltage control means for the voltage value of the solar cell. When the voltage is lower than the voltage, the voltage value of the solar cell is provided with a voltage replenishing unit that replenishes the voltage value set by the voltage control unit. And the compressor is operated.

According to a second aspect of the present invention, in the solar cell system according to the first aspect, the compressor uses the drive voltage generated by the drive voltage generation means based on the voltage value set by the voltage control means. When operated, when the voltage value of the solar cell is lower than the voltage value set by the voltage control means, the voltage replenishing means replenishes the voltage value of the solar cell,
A desired drive voltage is supplied to the compressor from the drive voltage generation means.

According to a third aspect of the present invention, in the solar cell system according to the first or second aspect, the voltage value set by the voltage control means is controlled by the compressor using only the power generated by the solar cell in fine weather. Is set to a value lower than the peak voltage at the time of operation.

According to a fourth aspect of the present invention, in the solar cell system according to any one of the first to third aspects, the voltage control means may be configured so that the compressor performs a purification operation and a backwash operation. And the drive voltage is set to a desired voltage value in accordance with each operation state. Further, in the solar cell system according to the fifth aspect, in the solar cell system according to the fourth aspect, the voltage control means may include a higher voltage when the compressor is performing the backwash operation than when performing the purification operation. It is characterized in that it is set to a value.

According to a sixth aspect of the present invention, in the solar cell system of the fourth or fifth aspect, the voltage control means detects an operating state of the compressor and changes a resistance value of the voltage control circuit. It is characterized in that the drive voltage of the compressor is set to a desired voltage value by making it variable. According to a seventh aspect of the present invention, in the solar cell system according to any one of the first to third aspects, the voltage control means detects an air temperature or a water temperature, and is driven when the compressor is performing a purification operation. It is characterized in that the voltage is controlled to a desired voltage value according to the air temperature or the water temperature.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the solar cell system according to the present invention will be described in detail with reference to the drawings.
FIG. 1 is a diagram showing a water purification apparatus which is an embodiment of a solar cell system using both a solar cell and a commercial power supply according to the present invention. This water purification device comprises a solar cell 1, a compressor 2, a commercial power supply 3, a diode 4, and a capacitor 5.
, Inverter 6, three-way valve 7, filter cartridge 8
, A controller 9 and an AC / DC conversion circuit 10. That is, this water purification device has two power supplies, the solar cell 1 and the commercial power supply 3, and when the compressor 2 is operated, the commercial power supply 3 is supplied by the shortage of the power generated by the solar cell 1 and the compressor 2 is supplied. It is configured to drive.

The power generated by the solar cell 1 is charged in the capacitor 5 through the diode 4. In addition, the inverter 6
Switches the DC voltage of the capacitor 5 to output a rectangular alternating current. Therefore, the peak value of the AC voltage is equal to the DC voltage of the capacitor 5. Inverter 6
The compressor 2 operates the load compressor 2 according to the input voltage. Further, the compressor 2 supplies air to the air lift pump of the filter cartridge 8 through the three-way valve 7 to supply water to the filter cartridge 8. The controller 9 switches between the cleaning operation and the backwashing operation by a timer or the like, and performs the backwashing by switching the three-way valve 7 and supplying air to the backwash nozzle during the backwashing.

One electric power system includes a solar cell 1, a diode 4, an inverter 6, and a compressor 2. The compressor 2 operates according to the amount of power generated by the solar cell 1. The output of the solar cell 1 and the output of the AC / DC converter 10 are combined at the input of the inverter 6. Therefore, another power system has a configuration including the commercial power supply 3, the AC / DC converter 10, the inverter 6, and the compressor 2. AC / DC
The converter 10 uses a commercial power supply 3 as a power supply, and its output voltage is set to a value lower than the peak voltage when the load (that is, the compressor 2) is operated only by the power generated by the solar cell in fine weather.

FIG. 2 is a diagram showing a compressor operating voltage with respect to a change in the amount of solar radiation. That is, the horizontal axis indicates time, and the vertical axis indicates compressor operating voltage, and shows how the compressor operating voltage changes during the day. Note that the curve a in the figure is the voltage of the solar cell 1. Now, when the output voltage of the AC / DC conversion circuit is set to E, the generated voltage of the solar cell 1 becomes AC
/ DC conversion circuit 10 is higher than the output voltage (time T
In 3), no power is supplied from the AC / DC conversion circuit 10, and the operation is performed only by the generated power of the solar cell 1. Such time T3 is, for example, a sunny day. Therefore, the voltage supplied from the solar cell 1 to the compressor 2 changes at a peak around noon. When there is no power generated by the solar cell 1 (time T1, T5), AC /
The compressor operating voltage is maintained at E by power supply using only the power of the DC conversion circuit 10. Such times T1 and T5 are, for example, nighttime or rainy weather.

Next, when the power generated by the solar cell 1 alone is insufficient (time T2, T4), the solar cell 1 and A
Electric power is supplied from both of the C / DC conversion circuits 10, and the AC / DC conversion circuit 10
More electric power is supplied, and the compressor operating voltage is maintained at E. That is, in the figure, the portion S1 is the supply power from the solar cell 1, and the portion S2 is the supply power from the AC / DC conversion circuit 10. Such times T1 and T5 are, for example, in the morning, afternoon, or cloudy. still,
Since the solar cell 1 has current source characteristics and the output voltage is dependent on the load, the voltage of the solar cell 1 has the same value as the output voltage of the AC / DC conversion circuit 10 regardless of the power generated by the solar cell 1. Become.

If the setting of the output voltage of the AC / DC conversion circuit 10 is too high, the usage efficiency of the solar cell 1 is greatly reduced. It is desirable to set a value lower than the peak voltage when the load (compressor 2) is operated only by the generated power of 1. However, if the output voltage of the AC / DC conversion circuit 10 is set too low, the power supplied to the compressor 2 during backwashing becomes insufficient and the amount of air becomes insufficient. Since a large amount of air is required at the time of back washing, the electric power supplied to the compressor 2 is increased.

Therefore, according to the present invention, the AC /
A device for changing the output voltage of the DC conversion circuit 10 to a voltage higher than that during the purification operation has been devised. FIG. 3 is an internal configuration diagram of an AC / DC conversion circuit applied to the solar cell system of the present invention. The AC / DC conversion circuit 10 includes a rectifier circuit 11, a coil 12, a transistor 13, and a diode 1.
4, a capacitor 15 and a control circuit 16. When an AC voltage is input from the commercial power supply 1, it is converted into a DC voltage by the rectifier circuit 11, and the DC voltage is further converted to the coil 12, the switching element 13, and the diode 1.
4 is converted to a set voltage by a DC chopper circuit. The switching element 13 is turned on by the control circuit 16.
It is driven N / OFF and outputs a PWM waveform.

FIG. 4 is a block diagram of a control circuit for driving and controlling the AC / DC conversion circuit of FIG. This control circuit 16
Is composed of an operational amplifier 17, a comparator 18, a transistor 19, and resistors R1, R2, and R3. That is, the feedback voltage of the output of the AC / DC conversion circuit is divided by the resistors R1, R2 and R3, and the operational amplifier 17 compares the divided voltage with the reference voltage to perform differential amplification. The output voltage of the operational amplifier 17 is input to the converter 18 and compared with a triangular wave to generate a PWM signal.

Such a general PWM control circuit is provided, and the transistor 19 is operated by a reverse cleaning command from the controller 9. The emitter and the collector of the transistor 19 are connected to both ends of R2, and when a reverse cleaning command is received from the controller 9, the transistor 19 is turned on,
R2 is short-circuited. Then, the feedback voltage input to the operational amplifier 17 decreases, and as a result, the output voltage is controlled to increase. As a result, the operating voltage of the compressor 2 at the time of backwashing increases, and a compressor or the like dedicated to backwashing becomes unnecessary.

However, the AC / DC conversion circuit 10
By using a boost converter as shown in FIG. 5, the operating voltage of the compressor 2 during backwashing can be automatically increased. FIG. 6 is a circuit diagram of a general boost converter. That is, in the boost converter, the PWM control circuit 21 performs control by feeding back the input voltage Vi, the output voltage Vo, and the load current Io. That is, the input voltage Vi is detected by the divided voltage of the resistors R1 and R2, the output voltage Vo is detected by the divided voltage of the resistors R3 and R4, and the negative overcurrent Io is detected by the resistor R5. Then, a PWM pulse is generated to control the switching of the transistor Q.

At the time of backwashing, the load on the compressor 2 becomes heavy, so that the overload current Io is increased so that the duty width of the PWM is increased, and the output voltage is increased. Also,
At the time of normal purification operation, the load becomes lighter, so that the negative overcurrent Io is reduced and the duty width of PWM is controlled to be narrower, so that the output voltage is reduced. In this way, the output voltage is automatically controlled to a desired value according to the purifying operation and the backwashing operation.

By the operation described above, even if the amount of solar radiation decreases, the required compressor operating voltage is always maintained, so that the purification operation can be continued at a certain level or more. Further, unlike the case where the solar battery and the commercial power supply are switched in accordance with the level of solar radiation, the operation is continued and the power generated by the solar battery can be used even when the solar radiation is small, so that it is efficient. Moreover, it can be realized with a very simple circuit configuration. In addition, by increasing the set voltage of the DC power supply at the time of backwashing, it is not necessary to prepare a pump or power supply for backwashing, and the water purification apparatus is simple and inexpensive.

Next, a water purification apparatus as another embodiment of the solar cell system of the present invention will be described. That is,
Generally, in lakes and rivers, the necessity of purification is high when the water temperature is high because the water is heavily contaminated, and the necessity of purification is low when the water temperature is low because the water is less contaminated. Therefore, when the necessity of purification in winter is low, a temperature sensor is provided to automatically reduce the operation amount of the compressor, and the operation amount of the compressor is controlled according to the water temperature.

FIG. 5 is another block diagram of a control circuit for driving and controlling the AC / DC conversion circuit of FIG. That is, FIG.
2 shows a state in which a temperature sensor is connected to the control circuit 16 shown in FIG. The operation of changing the division ratio of the feedback voltage by the resistors R1, R2, and R3 is the same as that in the case of FIG. In this embodiment, the temperature sensor 20 is internally turned on / off by a water temperature. When the water temperature is lower than a set value of the temperature sensor 20, the switch is turned off, and when the water temperature is higher than the set value, the switch is turned off. Is ON
Becomes Therefore, when the water temperature is lower than the set value,
When the switch of the temperature sensor 20 is turned off, the feedback voltage input to the operational amplifier 17 increases, and the output voltage of the AC / DC conversion circuit 10 has a low value.

On the other hand, when the water temperature is higher than the set value, the switch is turned on, the resistor R2 is short-circuited, and the feedback voltage input to the operational amplifier 17 is reduced, and
The output voltage of the C / DC conversion circuit 10 rises. In addition, using a thermistor instead of the temperature sensor 20 and the resistor R2,
It goes without saying that the same result as described above can be obtained even if the feedback voltage is changed by the thermistor resistance that changes with temperature.

As an effect of this embodiment, by changing the operation voltage setting according to the temperature, the operation amount of the compressor can be automatically increased when the necessity of purification is high in summer or the like. In addition, the operation level is changed according to the water temperature instead of operating at a constant set voltage regardless of the water temperature throughout the year, thereby further contributing to energy saving.

[0028]

As described above, according to the solar cell system of the present invention, the operation during purification can be continued at a certain level or more even if the amount of solar radiation decreases. Also, unlike when switching between solar cells and commercial power in accordance with the level of solar radiation, the operation is continuous and the power generated by the solar cells can be used even when the amount of solar radiation is small. Become a target. Moreover, it can be realized with a very simple circuit configuration. Further, even when power cannot be supplied from a commercial power supply due to a disaster or the like, operation using only solar cells is also possible. Further, by increasing the set voltage of the DC power supply at the time of backwashing, it is not necessary to prepare a pump or power supply for backwashing, and the whole water purification apparatus becomes simple and inexpensive. In addition, by changing the operation voltage setting according to the temperature, the operation amount can be automatically increased when the necessity of purification is high in summer or the like, and the setting voltage is lowered when the necessity of purification is low in winter or the like. Setting can contribute to energy saving.

[Brief description of the drawings]

FIG. 1 is a diagram showing an embodiment of a solar cell system using a solar cell and a commercial power supply in combination in the present invention.

FIG. 2 is a diagram showing a compressor operating voltage with respect to a change in the amount of solar radiation;

FIG. 3 shows an AC applied to the solar cell system of the present invention.
FIG. 3 is an internal configuration diagram of a / DC conversion circuit.

FIG. 4 is a configuration diagram of a control circuit that drives and controls the AC / DC conversion circuit of FIG. 3;

FIG. 5 is another configuration diagram of a control circuit that drives and controls the AC / DC conversion circuit of FIG. 3;

FIG. 6 is a circuit diagram of a general boost converter.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Solar cell 2 Compressor 3 Commercial power supply 4, 14 Diode 5, 15 Capacitor 6 Inverter 7 Three-way valve 8 Filter cartridge 9 Controller 10 AC / DC conversion circuit 11 Rectifier circuit 12 Coil 13, 19 Transistor 16 Control circuit 17 Operational amplifier 18 Comparator 20 Temperature sensor 21 PWM control circuit

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H02J 7/35 H01L 31/04 K F term (Reference) 5F051 BA05 BA17 JA18 KA03 5G003 AA06 BA01 DA04 DA15 DA18 GB03 GB06 5G066 HA15 HB06 5H030 AS01 BB01 BB07 BB21 DD20 FF22 FF41

Claims (7)

[Claims] 1. A solar cell system that operates a compressor using a solar cell and a commercial power supply or a storage battery in combination, comprising: a voltage control unit configured to set a voltage value of the commercial power supply or the storage battery to an arbitrary value; A drive voltage generation unit that generates a drive voltage for the compressor by using both the output voltage of the solar cell and the voltage control unit, and when a voltage value of the solar cell is lower than a voltage value set by the voltage control unit, Voltage supplementing means for supplementing the voltage value of the solar cell to the voltage value set by the voltage control means, by supplying power from the commercial power supply or the electric storage device by an insufficient amount of power generated by the solar cell. And a solar cell system configured to operate the compressor. 2. The compressor is operated by a drive voltage generated by the drive voltage generation means based on a voltage value set by the voltage control means, and a voltage value of the solar cell is set by the voltage control means. 2. The solar cell according to claim 1, wherein when the voltage is lower than the voltage value, the voltage replenishing means replenishes the voltage value of the solar cell, and supplies a desired driving voltage to the compressor from the driving voltage generating means. 3. Battery system. 3. The voltage value set by the voltage control means is:
3. The solar cell system according to claim 1, wherein the value is set to a value lower than a peak voltage when the compressor is operated only by the power generated by the solar cell in fine weather. 4. The voltage control means recognizes that the compressor is performing a purification operation and a backwash operation,
The solar cell system according to any one of claims 1 to 3, wherein the drive voltage is set to a desired voltage value according to each operation state. 5. The voltage control device according to claim 4, wherein the voltage control means sets a higher voltage value when the compressor is performing the backwashing operation than when performing the purification operation. Solar cell system. 6. The voltage control means sets a drive voltage of the compressor to a desired voltage value by detecting an operation state of the compressor and changing a resistance value of a voltage control circuit. The solar cell system according to claim 4 or 5, wherein 7. The voltage control means detects an air temperature or a water temperature, and controls a driving voltage when the compressor is performing a purifying operation to a desired voltage value according to the air temperature or the water temperature. The solar cell system according to claim 1.