JP2015053826A - Charge control device, charging apparatus, vehicle and charge control method - Google Patents

Abstract

A charging control device, a charging device, a vehicle, and a charging control method capable of suppressing deterioration of the life of a lead battery by performing refresh charging as needed.
A charging control unit 104 performs pulse charging to charge a lead battery 150 by gradually increasing a charging current at the start of charging, and a voltage detection unit 101 determines a voltage value of the lead battery 150 obtained thereby. To detect. The sulfation detection unit 102 detects the presence or absence of sulfation depending on whether or not the IV characteristic indicating the relationship between the current value and the voltage value of the charging current has linearity, and the charging control unit 104 determines whether or not the sulfation is present. Switch between refresh charge and normal charge.
[Selection] Figure 1

Description

  The present invention relates to a charge control device, a charging device, a vehicle, and a charge control method for controlling charging of a lead battery.

  Generally, in a lead battery, poorly soluble sulfation (lead sulfate; PbSO4) is generated due to a decrease in SOC (State Of Charge) and standing. When sulfation occurs, the battery capacity when the lead battery is fully charged decreases.

  For this reason, conventionally, for example, by periodically charging the lead battery once every seven days, sulfation is eliminated, and a decrease in battery capacity when the lead battery is fully charged is avoided ( For example, Patent Document 1).

Japanese Patent No. 4687768

  However, conventionally, since refresh charging is performed regularly regardless of the amount of sulfation, the frequency of refresh charging is more than necessary, and the electrode material is damaged, leading to deterioration of the life of the lead battery. is there.

  An object of the present invention is to provide a charge control device, a charge device, a vehicle, and a charge control method capable of suppressing deterioration of the life of a lead battery by performing refresh charging as necessary.

  A charge control device according to an aspect of the present invention is a charge control device that controls charging of a lead battery, and includes a charging unit that charges the lead battery, and a voltage detection unit that detects a voltage value of the lead battery. A sulfation detection unit for detecting sulfation of the lead battery based on a current-voltage characteristic of a charging current value from the charging unit and a voltage value detected by the voltage detection unit, and depending on the presence or absence of the sulfation The control part which switches whether the said lead battery is refresh-charged is taken.

  The charging device which concerns on 1 aspect of this invention is a charging device which charges a lead battery, Comprising: The charging part which charges the said lead battery, The voltage detection part which detects the voltage value of the said lead battery, The said charging part A sulfation detection unit for detecting sulfation of the lead battery based on a current-voltage characteristic of a charging current value from the voltage value detected by the voltage detection unit, and depending on the presence or absence of the sulfation, the lead battery And a controller that switches whether or not to perform refresh charging.

  A charge control method according to an aspect of the present invention is a charge control method in a charge control device for charging a lead battery, the step of charging the lead battery, the step of detecting a voltage value of the lead battery, Based on the current-voltage characteristics of the charging current value and the detected voltage value, the step of detecting the sulfation of the lead battery and switching whether or not to refresh charge the lead battery according to the presence or absence of the sulfation Steps.

  According to the present invention, it is possible to suppress deterioration of the life of the lead battery by performing refresh charging as necessary.

The block diagram which shows the structure of the charging device which concerns on one embodiment of this invention. The flowchart which shows the charge switching method in embodiment of this invention The figure which shows IV characteristic at the time of pulse charge in embodiment of this invention The figure which shows the variation of the arrangement position of a charge control part

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

(One embodiment)
<Configuration of charge control device>
A configuration of charge control device 100 according to an embodiment of the present invention will be described with reference to FIG.

  The charge control device 100 mainly includes a voltage detection unit 101, a sulfation detection unit 102, a storage unit 103, and a charge control unit 104. The charging control device 100 controls charging of the lead battery 150.

  The voltage detection unit 101 detects the voltage of the lead battery 150 and outputs the detection result to the sulfation detection unit 102.

  The sulfation detection unit 102 detects the presence or absence of sulfation based on the detection result output from the voltage detection unit 101 and the current instruction value to the charging unit 105 output from the charge control unit 104 described later, and stores the detection result. Output to the unit 103. Details of the sulfation detection unit 102 will be described later.

  The storage unit 103 stores the detection result of the presence or absence of sulfation input from the sulfation detection unit 102.

  The charging control unit 104 reads out the detection result of the presence or absence of sulfation from the storage unit 103, and performs switching control between the normal charging and the refresh charging for the charging unit 105 based on the read detection result. Note that a charge switching method will be described later. Further, the charging control unit 104 instructs the charging unit 105 to perform pulse charging at the start of charging. Here, the pulse charge refers to a charge that increases the current every time a pulse current having a certain time width is sent. At this time, the current instruction value is also instructed to the charging unit 105 so as to increase the current value every time a pulse is transmitted, and this current instruction value is output to the sulfation detection unit 102.

<Configuration of charging device>
The structure of the charging device 140 in one embodiment of the present invention will be described with reference to FIG.

  The charging device 140 mainly includes the charging control device 100, the charging unit 105, and the charging connector 106. Note that the configuration of the charging control apparatus 100 has been described above, and will be omitted.

  The charging unit 105 performs normal charging or refresh charging of the lead battery 150 by accumulating electric power supplied from a power source (not shown) via the charging connector 106 in the lead battery 150 according to the control of the charging control unit 104. When performing the refresh charge, the charging unit 105 increases the charging current or the charging voltage as compared with the normal charging to eliminate the sulfation.

  The charging connector 106 is connected to a power source (not shown).

  Note that the voltage detection unit 101, the sulfation detection unit 102, the charging control unit 104, and the charging unit 105 may be housed in one housing to form the charging device 140, or may be housed in separate housings. Thus, the charging device 140 may be configured.

  The load 160 is operated by electric power stored in the lead battery 150.

  The charging device 140 having the above configuration is, for example, a vehicle (not shown) that travels with electric power such as a HEV (Hybrid Electric Vehicle), a PEV (Plug-in Electric Vehicle), or an EV (Electric Vehicle) together with the lead battery 150 and the load 160. Can be installed.

<Charging switching method>
A charge switching method according to the embodiment of the present invention will be described with reference to FIG.

  First, the charging control unit 104 starts charging with the charging connector 106 connected to a power source (not shown) as a trigger (step ST301).

  Charging control section 104 instructs charging section 105 to perform pulse charging, and charging section 105 performs pulse charging (step ST302).

  The voltage detection unit 101 detects the voltage value of the lead battery 150 for each pulse in pulse charging (step ST303), and the sulfation detection unit 102 detects the voltage value detected by the voltage detection unit 101 and the pulse charging from the charging control unit 104. IV characteristics are calculated based on the current instruction value (step ST304).

  The sulfation detection unit 102 determines the presence or absence of sulfation based on the linearity of the IV characteristic (step ST305).

  If it is determined that sulfation has occurred (step ST305: YES), refresh charging is performed under the control of the charging control unit 104 (step ST306), and the process ends.

  On the other hand, when it is determined that sulfation has not occurred (step ST305: NO), normal charging is performed under the control of the charging control unit 104 (step ST307), and the process is terminated.

  As described above, the charging control unit 104 determines the presence / absence of sulfation based on the linearity of the IV characteristic during pulse charging, and switches between refresh charging and normal charging according to the presence / absence of sulfation.

<IV characteristics during pulse charging>
The IV characteristics at the time of pulse charging in the embodiment of the present invention will be described with reference to FIG. FIG. 3 (a) shows the IV characteristic when the sulfation is low, and FIG. 3 (b) shows the IV characteristic when the sulfation is high. In FIG. 3, the horizontal axis is current I and the vertical axis is voltage V. Here, for example, it is assumed that the voltage value of the voltage detection unit 101 is plotted when the current instruction value of the charging control unit 104 is set to 0A, 1.5A, 3A, and 6A.

  As can be seen from FIG. 3A, when the sulfation is small, the IV characteristic connecting the plots has a high linearity and is almost a straight line. On the other hand, as can be seen from FIG. 3B, when the sulfation is large, the IV characteristic has low linearity and a plot deviating from the straight line appears.

  As a method for determining linearity, for example, a straight line is obtained from each plot by the least square method or the like, and if the degree of divergence between the obtained straight line and the plot is within a predetermined range, the linearity is high and outside the predetermined range. If there is, it can be determined that the linearity is low. Note that the linearity determination method is not limited to this, and other existing methods may be used.

  Thus, since the linearity of the IV characteristic differs depending on the number of sulfations, the sulfation detection unit 102 can detect the presence or absence of sulfation based on the IV characteristics.

<Effect of Embodiment>
Thus, according to the present embodiment, the charge current is increased stepwise to charge the lead battery 150, and the voltage value of the lead battery 150 obtained thereby and the current value at that time are The presence or absence of sulfation is detected based on whether or not the IV characteristic indicating the relationship has linearity. As a result, refresh charging is performed when sulfation is occurring, and normal charging is performed when sulfation is not occurring, so that deterioration of the life of the lead battery can be suppressed.

  In this embodiment, pulse charging is defined as charging that increases the current value every time a pulse having a certain time width is sent, but the current value is decreased every time a pulse having a certain time width is sent. It is good also as charge.

  Moreover, although this Embodiment demonstrated the case where the charge control part 104 was included in the charge control apparatus 100, this invention is not restricted to this. For example, the charging control unit 104 may be included in the charging unit 105 or may be included in an electronic control unit (ECU) provided in the lead battery 150 as illustrated in FIG. Furthermore, as shown in FIG. 4B, the ECU may be included in an ECU that controls an AC / DC converter outside the vehicle. As described above, the charging control unit 104 may be provided anywhere as long as the function is realized.

  In the present embodiment, the number and time of refresh charging may be controlled according to the degree of divergence between the straight line used for determining the linearity and the plot.

  The charging control device, the charging device, the vehicle, and the charging control method according to the present invention are suitable for controlling the charging of the lead battery.

DESCRIPTION OF SYMBOLS 100 Charge control apparatus 101 Voltage detection part 102 Sulfation detection part 103 Memory | storage part 104 Charge control part 105 Charging part 106 Charging connector 140 Charging apparatus 150 Lead battery 160 Load

Claims (6)

A charge control device for controlling charge of a lead battery,
A charging unit for charging the lead battery;
A voltage detector for detecting a voltage value of the lead battery;
A sulfation detection unit that detects sulfation of the lead battery based on a current-voltage characteristic of a charging current value from the charging unit and a voltage value detected by the voltage detection unit;
A control unit that switches whether to refresh charge the lead battery according to the presence or absence of the sulfation,
A charge control device comprising: The charging unit performs pulse charging to increase the charging current each time a pulse current having a certain time width is sent at the start of charging.
The charge control device according to claim 1. The sulfation detection unit detects the sulfation based on a degree of linearity of the current-voltage characteristics.
The charge control device according to claim 1. A charging device for charging a lead battery,
A charging unit for charging the lead battery;
A voltage detector for detecting a voltage value of the lead battery;
A sulfation detection unit that detects sulfation of the lead battery based on a current-voltage characteristic of a charging current value from the charging unit and a voltage value detected by the voltage detection unit;
A control unit that switches whether to refresh charge the lead battery according to the presence or absence of the sulfation,
A charging device comprising: The lead battery;
A charging device according to claim 4;
Vehicle with. A charge control method in a charge control device for charging a lead battery,
Charging the lead battery;
Detecting a voltage value of the lead battery;
Detecting the sulfation of the lead battery based on the current-voltage characteristics of the charging current value and the detected voltage value;
Switching whether or not to refresh charge the lead battery according to the presence or absence of the sulfation;
A charge control method comprising:

Images