JPH10271871A - Motor driving device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the power from a solar battery and a battery, and, at the same time, to quickly charge the battery by controlling the number of revolutions per unit time of a motor which is driven with the electric power form the solar battery and/or battery to a prescribed value. SOLUTION: A PWM(pulse width modulation circuit) 16 always detects the number of revolutions per unit time of a motor 15 and, at the same time, controls the number of revolutions of the motor 15 to a prescribed value or its vicinity by chopping the direct current supplied to the motor 15 from a solar battery 12 or a battery 14 in a pulse and controlling the on-duty ratio of the pulse width of the pulse so that the detected number of revolutions (rotating speed) of the motor 15 may become a fixed value (speed). Therefore, the power consumption of the motor 15 is also nearly fixed to a prescribed value. Therefore, when the electric power generated from the solar battery 12 exceeds the nearly fixed power consumption of the motor 15, the excessive electric power is not used for increasing the number of revolutions of the motor 15, and so forth, but for charging the battery 14. Therefore, the charging time of the battery 14 can be shortened.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a motor driving device using a solar cell as a power source.

[0002]

FIG. 3 shows a conventional motor driving apparatus 1 of this kind.
This is an example of an electronic circuit diagram, in which a storage battery 4 is connected in parallel to a solar cell 2 via a backflow prevention diode 3, and the potential Vs of the solar cell 2 is higher than the potential Vc of the storage battery 4 (V
When s> Vc), DC power is supplied from the solar cell 2 to the DC motor 6 for driving the fan 5 and the like, and the motor 6 is driven.

When the power generated by the solar cell 2 is larger than the power consumption of the motor 6, the surplus power is charged to the storage battery 4. When the potential Vs of the solar cell 2 is lower than the potential Vc of the storage battery 4 (Vs <Vc), the electric power of the storage battery 4 is supplied to the motor 6 to drive the motor 6.

[0004] Other examples of this type of conventional drive motor device are described in Japanese Patent Application Laid-Open No. 8-98572 (hereinafter referred to as "prior art 2") and Japanese Patent Application Laid-Open No. 60-7499.
No. 5 (hereinafter referred to as prior art 3).

[0005]

However, in the conventional drive motor device 1 shown in FIG.
Cannot supply a constant voltage to the motor 6.

Therefore, when the motor 6 is driven by the solar cell 2, most of the power of the solar cell 2 is
It is supplied to and consumed. That is, the solar cell 2
Most of the surplus electric power of the storage battery 4 is consumed to increase the number of rotations of the motor 6 per unit time, that is, to increase the capacity of the fan 5 driven by the motor 6 such as the amount of air blown and the static pressure.
The amount of power used to store power is reduced. For this reason, there is a problem that the charging time of the storage battery 4 becomes long.

Further, even when the motor 6 is driven by the storage battery 4, most of the power when the storage battery 4 is fully charged is consumed for increasing the performance of the motor 6 or the fan 5, and the power consumption of the storage battery 4 is fast. There are issues.

In the prior art 2, the electric charge is exclusively stored in the electric charge accumulating means in the initial stage of starting the motor, and when the electric charge is sufficient, the motor is driven by the electric charge accumulating means and the solar cell. This does not disclose any means for solving the above problems.

The prior art 3 converts DC from a solar cell into AC by an inverter and supplies the AC to a motor, and does not disclose means for solving the above-mentioned problem.

Accordingly, the present invention has been made in view of such circumstances, and an object of the present invention is to provide a motor drive device capable of reducing power consumption from a solar cell and a storage battery and storing the storage battery quickly. Is to do.

[0011]

According to a first aspect of the present invention, there is provided a motor driving device comprising: a solar cell; a storage battery connected in parallel to the solar cell to store power from the solar cell; and at least one of the solar cell and the storage battery And a speed control means for controlling the number of revolutions of the motor per unit time to a predetermined value.

According to the present invention, the number of revolutions of the motor per unit time (hereinafter simply referred to as the number of revolutions) is controlled by the speed control means to be substantially constant at a predetermined value, so that the power consumption of the motor is also substantially constant. Become. For this reason, when the amount of power generated by the solar cell exceeds the power consumption of the motor, the surplus power is used for power storage of the storage battery without being consumed for increasing the performance of the motor. Therefore, the storage battery can be quickly stored, and the size and weight of the solar cell can be reduced.

Further, electric power at the time of full charge of the storage battery is also used for driving the motor at a constant rotation speed, and is not consumed for further increasing the capacity, so that the consumption capacity of the storage battery can be reduced. . Therefore, the size and weight of the storage battery can be reduced.

According to a second aspect of the present invention, there is provided a motor driving apparatus, wherein the speed control means controls an on-duty ratio of a pulse width of pulsed electric power supplied to the motor in accordance with the number of rotations per unit time of the motor. It is characterized by being.

According to the present invention, since the motor speed control means is a pulse width modulation circuit (PWM chopper),
Even if the input given to the PWM chopper from at least one of the solar battery and the storage battery fluctuates, the rotation speed of the motor can always be controlled to be constant.

According to a third aspect of the present invention, the motor driving device compares the potential of the solar battery with the potential of the storage battery, and connects the solar battery and the storage battery in series when the potential of the solar battery and the potential of the storage battery reach a predetermined ratio. Connection switching means;

Note that the control of the connection switching means does not necessarily require detection of the potential of the solar cell and the potential of the storage battery. It is only necessary that the connection be switched.

According to the present invention, when the amount of power generated by the solar cell is insufficient due to an insufficient amount of sunlight received or the like, when the potential of the solar cell and the potential of the storage battery reach a predetermined ratio, for example, When the potential is smaller than the storage battery potential, the connection between the solar battery and the storage battery is switched to the series connection by the connection switching means. For this reason, a high potential, which is obtained by adding the storage battery potential to the solar battery potential, is applied to the motor, so that the motor is driven without waiting for the solar battery potential or the storage battery potential to rise to the potential required to start the motor. In addition to being able to start, the power consumption of the storage battery can be reduced.

Conversely, when the solar cell potential is greater than the storage battery potential because the amount of power generated by the solar cell is sufficient,
Since the solar cell and the storage battery remain connected in parallel, only the high potential of the solar cell is applied to the motor.

In addition, since the rotation speed of the motor is constant and the power consumption is constant, the surplus power of the solar cell is used for power storage of the storage battery. Therefore, the storage time of the storage battery can be shortened.

According to a fourth aspect of the present invention, in the motor drive device, the connection switching means includes a power-on switching means for switching the solar battery and the storage battery to a series connection when the power is supplied to the motor.

According to the present invention, when the power is turned on, the power generation amount of the solar cell is insufficient, or the power storage amount of the storage battery is insufficient, or both of them. The switching means switches the connection between the solar cell and the storage battery to a series connection.

For this reason, since the potential obtained by adding the storage battery potential to the solar battery potential is applied to the motor, the motor can be started immediately without waiting for the solar battery potential and the storage battery potential to rise sufficiently. .

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. In these figures, the same or corresponding parts are denoted by the same reference characters.

FIG. 1 is an electronic circuit diagram of a motor drive device 11 according to a first embodiment of the present invention. In this figure, the motor drive device 11 is connected to a solar battery 12 and a storage battery 14 via a backflow prevention diode 13. , And a DC motor 15 for driving the fan 15a are connected in parallel to each other.
5 is a PWM (pulse width modulation circuit) which is a speed control means.
16 are inserted in series.

The fan 15a is used, for example, for ventilation or ventilation, and the number of revolutions per unit time may be a predetermined value and may be constant. do not do.

The PWM 16 constantly detects the number of rotations of the motor 15 per unit time, choppers the DC supplied from the solar battery 12 or the storage battery 14 to the motor 15 in a pulse shape, and controls the on-duty of the pulse width of the pulse. By controlling the ratio so that the detected rotation speed (speed) of the motor 15 becomes a constant number (speed), the rotation speed of the motor 15 is controlled to be substantially constant at a predetermined value. For this reason, the power consumption of the motor 15 is also substantially constant at a predetermined value.

Therefore, when the amount of power generated by the solar cell 12 exceeds a substantially constant power consumption of the motor 15, the surplus power is not consumed for increasing the capacity of the storage battery 14, such as increasing the rotation speed of the motor 15. Used for power storage. Therefore, the storage of the storage battery 14 can be accelerated.

When the potential of the solar cell 12 has not yet risen sufficiently, electric power is supplied to the motor 15 when the storage battery 14 is fully charged. The motor 15 is operated at a substantially constant speed. Since the power consumption is almost constant,
The electric power of the storage battery 14 is not consumed for increasing the performance of the motor 15. Therefore, the power consumption of the storage battery 14 can be reduced.

FIG. 2 is an electronic circuit diagram of a motor driving device 21 according to a second embodiment of the present invention. The motor driving device 21 is a motor driving device 11 according to the first embodiment.
Another feature is that a connection switching device 22 is provided.

The connection switching device 22 includes a first normally open contact 23a of a solenoid valve inserted in series on the cathode side of the storage battery 14 and a series circuit 24 for directly connecting the cathode side of the storage battery 14 to the anode side of the solar cell 12 in series. And the third normally open contact 23c of the solenoid valve inserted in series on the anode side of the solar cell 12 and the solar cell 12 and the storage battery 14 respectively. , And compares the potential Vs of the solar cell 12 with the potential Vc of the storage battery 14.
Of the normally open contacts 23a, 23b, 23c. In FIG. 2, reference numeral 26 denotes a power switch for turning on the power.

The control means 25 is composed of, for example, a microprocessor or the like. After the power switch 26 is turned on (ON), the potential Vs of the solar cell 12 and the potential Vc of the storage battery 14 are compared. Sometimes the first
While the third normally open contacts 23a and 23c are closed to switch the solar cell 12 and the storage battery 14 in parallel connection, when the solar cell potential Vs <the storage battery potential Vc, the second normally open contact 23b
Only the solar cell 12 and the storage battery 14 are switched to a series connection by closing only.

Therefore, when the power switch 26 is turned on, the control means 25 compares the potential Vs of the solar cell 12 with the potential Vc of the storage battery 14, and when the solar cell potential Vs ≧ the storage battery potential Vc, the control means 25 The first and third normally open contacts 23a and 23c are closed.

For this reason, since the solar cell 12 and the storage battery 14 are connected in parallel, a DC voltage having a solar cell potential Vs higher than the storage battery potential Vc is applied to the PWM 16.

The PWM 16 converts the direct current input thereto into pulses, and controls the on-duty ratio of the pulse width so that the number of revolutions of the motor 15 is substantially constant at a predetermined value, and supplies power to the motor 15. . As a result, the motor 15 is always operated at a predetermined rotation speed and substantially constant. For this reason, the power consumption of the motor 15 is always substantially constant at a predetermined value.

Therefore, when the amount of power generated by the solar cell 12 exceeds the substantially constant power consumption of the motor 15, the surplus power is not consumed for increasing the performance of the motor 15 or the fan 15a, but the power storage of the storage battery 14 is performed. Therefore, the storage battery 14 can be fully charged quickly.

On the other hand, the solar cell potential Vs <the storage battery potential Vc
In this case, the control means 25 closes only the second normally open contact 23b.

For this reason, since the solar battery 12 and the storage battery 14 are switched to the series connection, a high potential obtained by adding the storage battery potential Vc to the solar battery potential Vs is applied to the motor 15 via the PWM 16 and the motor 15 Drives almost constant.

Therefore, even when the solar cell potential Vs or the storage battery potential Vc has not risen to the potential required to start the motor 15, the motor 15 can be started and the power consumption of the storage battery 14 can be reduced. Can be done.

When the power switch 26 is turned on, the control means 25 controls the solar cell potential Vs and the storage battery potential Vc.
Regardless of the above, a configuration may be adopted in which only the second normally open contact 23b is closed to switch the solar cell 12 and the storage battery 14 to a series connection.

According to this, when the power switch 26 is turned on, the solar cell potential Vs or the storage battery potential Vc
Even when the potential has not risen sufficiently to the potential required to start the motor 5, the motor 15 can be easily started because the potential obtained by adding the storage battery potential Vc to the solar battery potential Vs can be applied to the motor 15. Can be done.

Further, the PWM 16 in each of the above embodiments is used.
May be replaced with a constant voltage power supply such as a DC-DC converter. The DC-DC converter converts the direct current of which the voltage from the solar battery 12 and the storage battery 14 fluctuates to a direct current whose voltage is constant at a predetermined value and supplies the direct current to the motor 15, thereby reducing the number of rotations and power consumption of the motor 15. May be configured to be substantially constant.

Further, the DC motor 15 in each of the above embodiments may be replaced by an AC motor (not shown) such as an induction motor. In this case, the PWM 6 is replaced by an inverter, and the inverter is used to control the AC motor. It is necessary to control the rotation speed to be substantially constant at a predetermined value.

That is, while the inverter always detects the rotation speed of the AC motor, the inverter supplies DC from the solar battery 12 or the storage battery 14 such that the rotation speed is substantially constant at a predetermined value.
The power is converted into an AC having a predetermined frequency and supplied to an AC motor. Thus, the rotation speed of the AC motor is substantially constant at the predetermined value, so that the power consumption of the AC motor can be constant at the predetermined value, similarly to the DC motor 15 described above.

[0045]

As described above, according to the first aspect of the present invention, the number of rotations of the motor per unit time (hereinafter simply referred to as the number of rotations) is controlled by the speed control means so as to be substantially constant at a predetermined value. In addition, the power consumption of the motor is also substantially constant. For this reason, surplus power in which the amount of power generated by the solar cell exceeds the power consumption of the motor is used for power storage of the storage battery without being consumed for increasing the performance of the motor. Therefore, the storage battery can be quickly stored, and the size and weight of the solar cell can be reduced.

Further, the electric power at the time of full charge of the storage battery is used for the operation of the motor at a constant rotation speed, and is not consumed for further increasing the capacity, so that the consumption capacity of the storage battery can be reduced. . Therefore, the size and weight of the storage battery can be reduced.

According to the motor driving device of the second aspect, since the motor speed control means is a pulse width modulation circuit (PWM chopper), the input supplied to the PWM chopper from at least one of the solar battery and the storage battery varies. Also, the rotation speed of the motor can always be controlled to be constant.

According to the motor driving device of the third aspect, since the power generation amount of the solar cell is insufficient due to insufficient light receiving amount of sunlight, etc., when the solar cell potential <the storage battery potential,
The connection switching means switches the connection between the solar cell and the storage battery to a series connection. For this reason, a high potential, which is obtained by adding the storage battery potential to the solar battery potential, is applied to the motor, so that the motor is driven without waiting for the solar battery potential or the storage battery potential to rise to the potential required to start the motor. In addition to being able to start, the power consumption of the storage battery can be reduced.

Conversely, when the solar cell potential ≥ the storage battery potential because the amount of power generated by the solar cell is sufficient,
Since the solar cell and the storage battery remain connected in parallel, only the high potential of the solar cell is applied to the motor.

In addition, since the number of rotations of the motor is constant and the power consumption is constant, the surplus power of the solar cell is used for power storage of the storage battery. Therefore, the storage time of the storage battery can be shortened.

According to the motor driving device of the fourth aspect, when the power is turned on, the power generation amount of the solar cell is insufficient, or the storage amount of the storage battery is insufficient, or both. At that time, the connection between the solar battery and the storage battery is switched to the serial connection by the connection switching means.

For this reason, since the potential obtained by adding the storage battery potential to the solar battery potential is applied to the motor, the motor can be started immediately without waiting for the solar battery potential and the storage battery potential to rise sufficiently. .

[Brief description of the drawings]

FIG. 1 is an electronic circuit diagram of a motor drive device according to a first embodiment of the present invention.

FIG. 2 is an electronic circuit diagram of a motor drive device according to a second embodiment of the present invention.

FIG. 3 is an electronic circuit diagram of a conventional motor driving device.

[Explanation of symbols]

 11, 21 Motor drive device 12 Solar cell 14 Storage battery 15 Motor 16 PWM (speed control means) 22 Connection switching device 23a, 23b, 23c First, second, third normally open contact 25 Control means

Claims (4)

[Claims] 1. A solar cell; a storage battery connected in parallel to the solar cell to store power from the solar cell; a motor driven by power from at least one of the solar cell and the storage battery; And a speed control means for controlling the number of rotations per unit time to a predetermined value at a constant value. 2. The apparatus according to claim 1, wherein the speed control means is a pulse width modulation circuit for controlling an on-duty ratio of a pulse width of pulsed electric power applied to the motor in accordance with the number of rotations per unit time of the motor. The motor drive device according to claim 1. 3. A connection switching means for comparing the potential of the solar battery with the potential of the storage battery, and switching the solar battery and the storage battery to a serial connection when the potential of the solar battery and the potential of the storage battery have a predetermined ratio. The motor drive device according to claim 1, wherein the motor drive device is provided. 4. The connection switching means according to claim 1, further comprising: a power-on switching means for switching the solar battery and the storage battery to a serial connection when the power is supplied to the motor. A motor drive according to one of the preceding claims.