Charge/discharge control method, charge/discharge controller, and power generation system with charge/discharge controller

• US 5,751,133 A
• Filed: 03/26/1996
• Issued: 05/12/1998
• Est. Priority Date: 03/29/1995
• Status: Expired due to Fees

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Sato, Hiroshi, Takehara, Nobuyoshi, Fukae, Kimitoshi
• Primary Examiner(s): TSO, EDWARD H
• Application Number:
  US08/622,584
• Time in Patent Office: 777 Days
• Field of Search: 320/2, 320/5, 320/12, 320/13, 320/14, 320/21, 320/28, 320/30, 320/39, 320/61, 136/DIG. 2
• US Class Current: 320/101
• CPC Class Codes: H01M 10/465 with solar battery as charging system
• CPC Class Codes: H02J 7/35 with light sensitive cells
• CPC Class Codes: Y02E 10/56 Power conversion systems, e.g. maximum power point trackers
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

In a charge/discharge control system for a charging the output of a storage battery from a solar cell, the output voltage of the storage battery connected to a node between the solar cell output and a load is detected. If the detected voltage is less than a first setting value, discharge from the storage battery to the load is inhibited. The discharge inhibition is released in response to a discharge inhibition release command after the storage battery voltage increases to a second setting value.

Claims

1. A power generation system comprising a solar cell and a load connected through a first wiring, and a storage battery connected through a second wiring to a node on said first wiring between said solar cell and said load, wherein:

a first setting value preliminary set for preventing a state of discharging from said storage battery, and a second setting value preliminary set at a value greater than the first setting value for releasing the prevention of the discharging from the discharging prevention state of said storage battery are designated; and

control means for controlling a connecting state of said first wiring, so that, starting a power supply by the discharging from said storage battery to said load thereby reducing a voltage of said storage battery according to a power consumption of said load, when the voltage of said storage battery reaches the first setting value, said control means sets at a disconnecting state said first wiring between said node and said load thereby preventing the discharging from said storage battery; and

so that, charging said storage battery with an output from said solar cell, when the voltage of said storage battery reaches the second setting value, said control means changes the disconnecting state of said first wiring into the connecting state thereby releasing the state of preventing the discharging from said storage battery to said load to supply the power from said storage battery to said load.

2. A power generation system comprising a solar cell and a load connected through a first wiring, and a storage battery connected through a second wiring to a node on said first wiring between said solar cell and said load, wherein:

a first setting value preliminary set for preventing a state of discharging from said storage battery, a second setting value preliminary set at a value greater than the first setting value for releasing the prevention of the discharging from the discharging prevention state of said storage battery, and a third setting value preliminary set for preventing an excessively charged state of said storage battery are designated; and

control means for controlling a connecting state of said first wiring, so that, starting a power supply by the discharging from said storage battery to said load thereby reducing a voltage of said storage battery according to a power consumption of said load, when the voltage of said storage battery reaches the first setting value, said control means sets at a disconnecting state said first wiring between said node and said load thereby preventing the discharging from said storage battery;

so that, charging said storage battery with an output from said solar cell, when the voltage of said storage battery reaches the second setting value, said control means changes the disconnecting state of said first wiring into the connecting state thereby releasing the state of preventing the discharging from said storage battery to said load to supply the power from said storage battery to said load; and

so that, when the voltage of said storage battery charged with the output from said solar cell reaches the third setting value, said control means sets at a disconnecting state the first wiring between said node and said solar cell.