JP5055810B2 - Solar cell power control device - Google Patents

Description

  The present invention relates to a power control device for a solar cell that uses a solar cell as a power source and controls a voltage supplied from the solar cell.

  Conventionally, electrical components in a vehicle are driven by a voltage acquired from a solar cell. For example, in Patent Document 1, in an electronic device provided in a vehicle including a storage battery and a solar battery, when it is detected that the power supply voltage of the storage battery is not normal, the power supply from the solar battery to the electronic device is cut. A technique for preventing electronic devices from being destroyed by solar cell output is described.

JP-A-5-244732

  However, in the technique described in Patent Document 1, when the voltage of the solar cell is gradually increased at the time of startup, the voltage of the electronic device may be unstable and the electronic device may be in an abnormal state. Therefore, after that, even if the supply voltage from the solar battery is stabilized, there is a case where the control for charging the storage battery is not normally executed.

  The present invention has been made to solve the above problems, and provides a power control device for a solar cell that can be reliably activated without being affected by the voltage supplied from the solar cell. The purpose is to do.

In one aspect of the present invention, a solar cell power control device that controls a voltage supplied from the solar cell using a solar cell as a power source, the solar cell power control device continuously powering for a certain period of time. The power supply control device is of a type in which the power supply is turned off when the rise of the power supply is not performed, and determines whether or not the voltage supplied from the solar cell has dropped once after exceeding a predetermined value at startup. A voltage drop determination unit; and a power supply reset unit that continues to maintain the power supply reset for a predetermined time when the voltage drop determination unit determines that the voltage has dropped after exceeding a predetermined value. The power reset means continues to maintain the power reset state for the predetermined time when the voltage supplied from the solar cell is less than the predetermined voltage after the predetermined time elapses. , When the voltage supplied from the solar cell after the elapse of the predetermined time is a predetermined voltage or more, further comprising a power source activating means for starting the power supply.

The above-described power control device for a solar cell is suitably used for controlling a voltage supplied from the solar cell using the solar cell as a power source. The solar battery power control device is a power control device of a type that is in a power-off state if the power supply is not raised for a certain period of time. The voltage drop determination means determines whether or not the voltage supplied from the solar cell has dropped after once exceeding a predetermined value at startup. Specifically, the voltage drop determination means determines whether or not the voltage supply of the solar cell is unstable. The power supply reset means continues to maintain the power supply reset for a predetermined time when the voltage drop determination means determines that the voltage has dropped after exceeding a predetermined value. That is, the power resetting means performs control to cut off such voltage supply when the solar cell supplies an unstable voltage. Thereby, the power supply control device of the solar cell can be appropriately activated without being affected by the supply voltage of the solar cell. In other words, the power control device for the solar cell can be reliably activated by suppressing the power-off state and the difficulty of returning.
Further, the power reset means keeps the power supply reset again for a predetermined time when the voltage supplied from the solar cell is less than the predetermined voltage after the predetermined time elapses. In this case, the power control device for the solar cell continues to reset the power until the supply voltage of the solar cell is stabilized.
Furthermore, the power supply activation means activates the power supply when the voltage supplied from the solar cell is equal to or higher than the predetermined voltage after a predetermined time has elapsed. Thereby, the power supply control device of the solar cell can be surely activated when the supply voltage of the solar cell is stabilized.

  Preferably, the power supply starting means further includes a charge control means for starting charging the storage battery after the power supply is started. Thereby, the power supply control apparatus of a solar cell can perform charge to a storage battery appropriately.

  Preferred embodiments of the present invention will be described below with reference to the drawings.

[System configuration]
First, the structure of the solar cell charging system which concerns on embodiment of this invention is demonstrated.

  FIG. 1 is a schematic configuration diagram illustrating a solar battery charging system according to the present embodiment. The solar cell charging system 10 mainly includes a solar cell panel 1, a charge control ECU (Electric Control Unit) 2, and a storage battery 3. The solar battery charging system 10 is mounted on, for example, a vehicle.

  The solar cell panel 1 is made of amorphous silicon having a photoelectric conversion function. The voltage generated by the solar cell panel 1 is supplied to the charging control ECU 2 as indicated by an arrow S1.

  The charge control ECU 2 is a microcomputer composed of various drive circuits and is driven using a voltage supplied from the solar cell panel 1 as a power source. Further, the charging control ECU 2 controls the supplied voltage so as to be appropriately activated by the voltage supplied from the solar cell panel 1. Further, the charging control ECU 2 performs control for charging the storage battery 3 with the voltage supplied from the solar battery panel 1 as indicated by an arrow S2. Thus, charge control ECU2 operate | moves as a power supply control apparatus of the solar cell in this invention. Specifically, the charge control ECU 2 functions as a voltage drop determination unit, a power supply reset unit, a power supply activation unit, and a charge control unit.

  The storage battery 3 is constituted by a lead storage battery or the like, and charges a voltage supplied via the charge control ECU 2. The voltage charged by the storage battery 3 is used to drive electrical components in the vehicle. When the solar battery charging system 10 is mounted on a hybrid vehicle, the voltage stored by the storage battery 3 can be used when the vehicle is electrically assisted.

[Control Method Performed by Charge Control ECU]
Next, a control method performed by the charge control ECU 2 according to the present embodiment will be described.

  In the present embodiment, the charging control ECU 2 determines whether or not the voltage supplied from the solar cell panel 1 has dropped after once exceeding a predetermined voltage at the time of activation (hereinafter referred to as supply of such a solar cell panel 1). The voltage is also simply referred to as “unstable voltage”.) When it is determined that the unstable voltage is supplied, control is performed to forcibly reset the power supply of the charging control ECU 2 for a predetermined time. This is because the voltage in the charging control ECU 2 becomes unstable when the voltage of the solar battery panel 1 is gradually increased when the charging control ECU 2 is started up, and the charging control ECU 2 may be in an abnormal state. Because there is sex. Specifically, due to its characteristics, the charging control ECU 2 enters a power-off state if the power supply is not raised continuously for a certain period of time. In such a power-off state, the charge control ECU 2 cannot be restored unless it is forcibly reset.

  Therefore, in the present embodiment, when an unstable voltage is supplied from the solar cell panel 1, the power supply of the charge control ECU 2 is forcibly reset for a predetermined time, thereby causing a problem from such a solar cell panel 1. Performs control to shut off the stable voltage supply. Specifically, the power supply of the charge control ECU 2 is continuously reset until the supply voltage of the solar battery panel 1 is stabilized, and when the supply voltage is stabilized, the charge control ECU 2 is activated. Thereby, since it can suppress that charge control ECU2 will be in an abnormal state and will be in a power-off state, charge control ECU2 can be started appropriately.

  FIG. 2 is a diagram for explaining a problem that may occur when the charging control ECU 2 does not perform the control according to the present embodiment. That is, a problem that may occur in a general charge control ECU will be described.

  FIG. 2 shows time on the horizontal axis and voltage on the vertical axis. Here, a solid line A1 indicates a generated voltage of the solar cell panel 1 (hereinafter referred to as “solar voltage”), and a broken line A2 indicates a voltage supplied to the charging control ECU 2 (hereinafter referred to as “ECU voltage”). Is shown. Furthermore, the time t10 has shown the time when the solar cell panel 1 started electric power generation. For example, the time when sunlight starts to enter the solar cell panel 1 is shown.

  As shown in FIG. 2, it can be seen that the solar voltage rises slowly from time t11 until the voltage rises and falls repeatedly during the period from time t11 to time t13. After that, the solar light voltage is substantially constant after time t13 without decreasing the voltage. For example, when the weather changes from cloudy to sunny, a solar voltage as shown in FIG. 2 is obtained.

  On the other hand, the ECU voltage is substantially “0 (V)” until time t11, and it can be seen that the voltage increases near time t11. This is because the solar voltage exceeds a predetermined voltage (for example, 11 (V)). The ECU voltage is found to increase and decrease so as to follow the sunlight voltage during the period from time t11 to time t12. For example, the ECU voltage drops to 4 to 5 (V). Next, it is understood that the ECU voltage drops to “0 (V)” at time t12, and the state of “0 (V)” continues after time t12. This indicates that the charging control ECU is in a power-off state (voltage is “0 (V)”). This is because during the period from time t11 to time t12, the voltage supplied to the charge control ECU is in an unstable state, and the power supply in the charge control ECU is not continuously raised for a certain period of time. When the power is turned off as described above, the charge control ECU cannot be restored unless it is forcibly reset.

  In order to suppress the occurrence of the problems as described above, the charging control ECU 2 according to the present embodiment performs the following control.

  FIG. 3 is a diagram for explaining a control method performed by the charge control ECU 2 according to the present embodiment. FIG. 3 also shows time on the horizontal axis and voltage on the vertical axis. Further, the solid line B1 indicates the sunlight voltage, and the broken line B2 indicates the ECU voltage. Furthermore, the time t20 has shown the time when the solar cell panel 1 started electric power generation.

  As shown in FIG. 3, it can be seen that the solar voltage rises slowly until time t21, and the voltage rises and falls repeatedly during the period from time t21 to time t23. And the solar light voltage is a substantially constant voltage, without the voltage falling after time t23.

  On the other hand, the ECU voltage is generally “0 (V)” until time t21, and it can be seen that the voltage increases near time t21. This is because the solar voltage exceeds a predetermined voltage (for example, 11 (V)). Thereafter, at time t22, the ECU voltage is found to be “0 (V)”. In the period T from time t22 to time t24, the ECU voltage is maintained at “0 (V)”. This is because the charging control ECU 2 determines that the voltage supplied from the solar cell panel 1 has dropped once it exceeds a predetermined voltage at the time of startup, and executes control to reset the power supply to “0 (V)”. Because. More specifically, the charging control ECU 2 resets the power source to “0 (V)” for a predetermined time (corresponding to the period T) after the voltage supplied from the solar cell panel 1 is reduced, and the solar cell panel 1 The control that keeps shutting off the voltage supplied from is executed.

  And charge control ECU2 determines whether a power supply may be turned on by performing determination with respect to solar voltage at the time t24 after predetermined time progress. Specifically, the charging control ECU 2 determines whether or not the sunlight voltage is equal to or higher than a predetermined voltage. In this case, since it is determined that the sunlight voltage is equal to or higher than the predetermined voltage, the charging control ECU 2 turns on the power. At this time, since the sunlight voltage is stable, there is almost no possibility that the charging control ECU 2 becomes in an abnormal state and the power is turned off. And charge control ECU2 starts the charge control to the storage battery 3, after turning ON a power supply. If the solar voltage is less than the predetermined voltage after the predetermined time has elapsed, the charging control ECU 2 executes control for cutting off the solar voltage for a predetermined time without turning on the power.

  As the charge control ECU 2 performs control in this way, the charge control ECU 2 can be appropriately activated without being affected by the supply voltage of the solar cell panel 1. In other words, the charge control ECU 2 can be reliably started by suppressing the power-off state and the difficulty of returning. Therefore, the charging control ECU 2 can appropriately start charging the storage battery 3.

[Charge control processing]
Next, the charge control process according to the present embodiment will be described. In this process, the charging control ECU 2 performs a process for appropriately starting with the voltage supplied from the solar battery panel 1 and a process for charging the storage battery 3 with the voltage supplied from the solar battery panel 1. Do.

  FIG. 4 is a flowchart showing the charging control process. This process is executed by the charge control ECU 2.

  First, in step S101, the charging control ECU 2 determines whether or not the supply voltage from the solar battery panel 1 is 11 (V) or more. That is, the charge control ECU 2 determines whether or not the supply control ECU 2 can be activated by determining whether or not the supply voltage is equal to or higher than a predetermined voltage. If the supply voltage is 11 (V) or higher (step S101; Yes), the process proceeds to step S102. In this case, the charging control ECU 2 turns on the power (step S102). Then, the process proceeds to step S103. On the other hand, when the supply voltage is less than 11 (V) (step S101; No), the process returns to step S101. That is, the determination in step S101 is repeatedly executed until the supply voltage becomes 11 (V) or higher.

  In step S103, the charging control ECU 2 determines whether or not the supply voltage is less than 11 (V). Here, the charging control ECU 2 determines whether or not the supply voltage has dropped to less than 11 (V) after the power is turned on (that is, after the supply voltage once becomes 11 (V) or more). is doing. That is, the charging control ECU 2 determines whether or not the supply voltage of the solar battery panel 1 is unstable.

  If the supply voltage is less than 11 (V) (step S103; Yes), the process proceeds to step S104. In this case, since there is a high possibility that the supply voltage of the solar battery panel 1 is unstable, the charging control ECU 2 executes processes of steps S104 to S106 described later. On the other hand, when the supply voltage is 11 (V) or more (step S103; No), the process proceeds to step S108. In this case, since the possibility that the supply voltage of the solar battery panel 1 is unstable is low, the charging control ECU 2 starts charging the storage battery 3 (step S108). Then, the process exits the flow.

  In step S104, the charging control ECU 2 resets the power supply to “0 (V)”. In other words, the charging control ECU 2 starts control for cutting off the voltage supplied from the solar cell panel 1. This is because the charging control ECU 2 is prevented from being in an abnormal state and being in a power-off state by shutting off the supply of unstable voltage from the solar cell panel 1. Then, the process proceeds to step S105.

  In step S105, the charging control ECU 2 stands by until a predetermined time elapses. Specifically, the charging control ECU 2 continues to execute control for resetting the power source to “0 (V)” for a predetermined time. That is, the process of step S105 is performed to secure time for resetting the power supply to “0 (V)”. Then, when the predetermined time has elapsed, the process proceeds to step S106.

  In step S106, the charging control ECU 2 determines whether or not the supply voltage is 11 (V) or higher. That is, the charge control ECU 2 determines whether or not the supply voltage of the solar battery panel 1 has become stable. If the supply voltage is 11 (V) or higher (step S106; Yes), the process proceeds to step S107. In this case, since the supply voltage of the solar cell panel 1 is in a stable state, the charging control ECU 2 turns on the power (step S107). Then, the process proceeds to step S108, and the charging control ECU 2 starts charging control for the storage battery 3.

  On the other hand, when the supply voltage is less than 11 (V) (step S106; No), the process returns to step S104, and the charge control ECU 2 resets the power supply to “0 (V)” again. And a process progresses to step S105 and charge control ECU2 continues the state which reset the power supply for the predetermined time. Next, the process proceeds to step S106, and the charging control ECU 2 determines whether or not the supply voltage is 11 (V) or more. In this way, by repeating the processes of steps S104 to S106, the process waits until the supply voltage of the solar cell panel 1 becomes stable with the power supply maintained in reset.

  Thus, according to the charge control process according to the present embodiment, the charge control ECU 2 can be appropriately activated without being affected by the supply voltage of the solar cell panel 1. That is, it is possible to suppress the charging control ECU 2 from being in a power-off state and difficult to return, and to be reliably started. Therefore, the charging control ECU 2 can appropriately execute the charging of the storage battery 3.

  In addition, although the embodiment which applies the power supply control apparatus of a solar cell to a vehicle was shown above, it is not limited to this. In another example, instead of being applied to a vehicle, a power control device for a solar cell can be applied to a house or the like.

  Moreover, although the power supply control apparatus (charge control ECU2) of a solar cell showed the embodiment which performs control which charges the voltage supplied from a solar cell to a storage battery in the above, it is not limited to this. In another example, the power control device of the solar cell performs control for driving various electrical components using the voltage supplied from the solar cell, instead of performing control to charge the voltage supplied from the solar cell. It can be carried out.

It is the schematic which shows schematic structure of the solar cell charging system which concerns on this embodiment of this invention. It is a figure for demonstrating the case where charge control ECU will be in a power-off state. It is a figure for demonstrating the control method which charge control ECU which concerns on this embodiment performs. It is a flowchart which shows the charge control process which concerns on this embodiment.

Explanation of symbols

1 Solar Panel 2 Charge Control ECU
3 Storage battery 10 Solar battery charging system

Claims (2)

A solar cell power control device for controlling a voltage supplied from the solar cell using a solar cell as a power source,
The power control device of the solar cell is a type of power control device that is in a power-off state if the power supply is not continuously raised for a certain period of time,
At the time of start-up, a voltage drop determination means for determining whether or not the voltage supplied from the solar cell has once decreased after a predetermined value;
A power reset means that continues to maintain the power reset for a predetermined time when the voltage drop determination means determines that the voltage has once dropped after exceeding a predetermined value ; and
The power reset means, when the voltage supplied from the solar cell after the predetermined time elapses is less than a predetermined voltage, continues to maintain the power reset again for the predetermined time;
A power control device for a solar cell, further comprising: a power start unit that starts the power when a voltage supplied from the solar cell is equal to or higher than a predetermined voltage after the predetermined time has elapsed . The solar cell power supply control device according to claim 1 , further comprising charge control means for starting charging of the storage battery after the power supply start means starts the power supply.

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