JP5822779B2 - Power storage system and charge / discharge control method thereof - Google Patents

Description

  The present invention relates to a household power source for a power storage system used as a power source for driving an electric vehicle and a plug-in hybrid vehicle motor, a quick charger, and a charge / discharge control method in the case of motor regeneration.

  Conventionally, a power regeneration system in which a high-power storage battery and a high-capacity storage battery are connected in parallel has a high-power storage battery responsible for instantaneous charge / discharge, and the high-capacity storage battery takes charge / discharge for a long time. It is known as a technique for preventing and extending the life.

  In addition, as a charging method for the power supply system for driving a hybrid automobile motor, the high-capacity storage battery outputs a fixed output according to fluctuations in power consumption, and the high-capacity storage battery has a constant output. A technique for increasing the life of a storage battery has also been proposed (see, for example, Patent Document 1).

  When a high-power storage battery and a high-capacity storage battery are connected via a DC / DC converter, the high-capacity storage battery can be charged from an external power source, and the high-power storage battery can be charged from motor regeneration. A technique that enables charging from a high-output storage battery to a high-capacity storage battery has also been proposed (see, for example, Patent Document 2).

  Further, when the voltage of the high output storage battery is lowered by driving the motor, the DC / DC converter is set in a boosted state, the high capacity storage battery is charged to the high output storage battery, and the DC / DC converter is set in the boost stop state. A technology that enables charging from a high-output storage battery to a high-capacity storage battery has also been proposed (see, for example, Patent Document 3).

  The bidirectional charging of the high-capacity storage battery and the high-output storage battery described in Patent Document 3 aims to prevent a decrease in output due to a voltage drop of the high-output storage battery during motor driving and a decrease in output of the power storage system at low temperatures. It is said.

Japanese Patent Laying-Open No. 2008-202959 (FIG. 2) JP 2007-335157 A (FIGS. 1 and 11) JP 2006-121874 A (FIG. 1)

Even when a high-power storage battery and a high-capacity storage battery are connected in parallel, the conventional power storage system has a high-capacity storage battery because all the current generated by motor regeneration flows to the high-capacity storage battery when the high-power storage battery is fully charged. There has been a problem that the life of the product becomes shorter.
In addition, when charging from an external power source using a quick charger rather than from a general household power source, a large current flows through the high-capacity storage battery, so that the life of the high-capacity storage battery is similarly reduced.
Furthermore, when it was going to eliminate the lifetime deterioration of the said high capacity | capacitance storage battery, there existed a subject that it had to charge only with a high output storage battery at the time of large current charge.

  The present invention has been made in order to solve the above-described problems, and a power storage system that realizes a long life of a high-capacity storage battery by being configured not to apply a large current to the high-capacity storage battery. And it aims at obtaining the charging / discharging control method.

A power storage system and a charge / discharge control method thereof according to the present invention detect a high-output storage battery and a high-capacity storage battery connected in parallel to an external power source and a motor, and a current that flows through the high-output storage battery attached to the high-output storage battery A current detecting device that performs charging, a DC / DC converter that controls charging / discharging from a motor to a high-capacity storage battery, an AC / DC converter that controls charging from an external power source to a high-power storage battery and a high-capacity storage battery, and an AC / DC converter A voltage detection device that detects the voltage of the external power supply attached, a switch that is connected in series to the high-capacity storage battery and disconnects the high-capacity storage battery from the circuit under predetermined conditions, and the detected values of the voltage detection device and the current detection device A controller that generates an ON / OFF command for the switch as input information. When external charging from parts supply, when the voltage detector detects the above predetermined voltage value, or, when regeneration from the motor, when the current detecting device detects more than a predetermined current value, generates a OFF command for the switch The controller generates an ON command for the switch when the voltage detection device detects less than a predetermined voltage value during external charging from the external power source, and uses both the high-power storage battery and the high-capacity storage battery. The circuit is configured to charge, and when the voltage detection device detects a predetermined voltage value or more, an OFF command for the switch is generated, and the circuit is configured to perform charging only with the high-power storage battery. is there.

  According to the present invention, in the case of rapid charging, charging is performed only with a high-power storage battery, so that the charging time can be shortened. In addition, rapid charging / discharging is not performed in a high-capacity storage battery, thereby extending the life. Can be realized.

It is a block diagram which shows the charge control circuit structure of the electrical storage system which concerns on Embodiment 1 of this invention. It is a flowchart which shows the charge control operation at the time of charging from the external power supply with respect to the electrical storage system which concerns on Embodiment 1 of this invention. It is a flowchart which shows the charging / discharging control operation | movement at the time of charging / discharging with respect to the electrical storage system which concerns on Embodiment 1 of this invention by the power running / regenerative operation of a motor. It is explanatory drawing which shows the capacity | capacitance maintenance factor (effect) of the electrical storage system which concerns on Embodiment 1 of this invention. It is explanatory drawing which shows the charge time (effect) of the electrical storage system which concerns on Embodiment 1 of this invention.

Embodiment 1 FIG.
Embodiment 1 of the present invention will be described below with reference to the drawings.
1 is a block diagram showing a charge control circuit configuration of a power storage system according to Embodiment 1 of the present invention.
In FIG. 1, a motor 2 is connected to a power storage system 1 via an inverter 3, and an AC external power supply 4 is connected to the power storage system 1.

  The inverter 3 controls charging / discharging between the power storage system 1 and the motor 2. When the motor 2 is driven, the motor 3 is electrically connected between the power storage system 1 and the motor 2. While driving, charging / discharging is advanced between the electrical storage system 1 and the motor 2. On the other hand, when the motor 2 is stopped, the power storage system 1 and the motor 2 are insulated.

  The power storage system 1 includes a high-output storage battery 5p and a high-capacity storage battery 5c connected in parallel, a bidirectional DC / DC converter 6 inserted between the high-output storage battery 5p and the high-capacity storage battery 5c, and a high-capacity storage battery 5c. Are connected in series to each other and switch ON / OFF, an AC / DC converter 8 inserted between the external power supply 4 and the high-capacity storage battery 5c, and a voltage detection device 9 connected to the AC / DC converter 8. And a current detection device 10 connected to the high-output storage battery 5p, and a controller 11 that generates a switching command for the switch 7 in accordance with each detection value from the voltage detection device 9 and the current detection device 10.

The high output storage battery 5p is composed of a storage battery having a small internal resistance, and has a configuration capable of charging and discharging a large current.
Here, a lithium ion secondary battery is used as the high-power storage battery 5p, hard carbon (non-graphitizable carbon) is used as the negative electrode material, and lithium transition metal oxide (LiNi1 / 3Mn1 /) is used as the positive electrode material. 3Co1 / 3O2 and LiMn2O4) are used.

  Moreover, in the cell structure of the high-output storage battery 5p, the positive and negative electrodes are thinned in order to improve the output characteristics. The voltage of the high-power storage battery 5p is preferably in the range of 350 to 400 [V].

The high-capacity storage battery 5c is weak against large current charging / discharging, but has a configuration that has a large storage capacity and can be used for a long time.
Here, a lithium ion secondary battery is used as the high-capacity storage battery 5c, graphite (graphite) is used as the negative electrode material, and lithium transition metal oxides (LiCoO2, LiNiO2) are used as the positive electrode material. Yes.

In the cell structure of the high-capacity storage battery 5c, the positive and negative electrodes are thickened in order to improve the storage capacity. The voltage of the high-capacity storage battery 5c is a voltage that can be boosted by the DC / DC converter 6, and can be freely set within a range of 50 to 300 [V].
The external power source 4 includes a 100 [V] power source for general households, a 200 [V] power source, and a quick charger for electric vehicles.

The AC / DC converter 8 receives the voltage Vo of the external power source 4 and applies the boosted voltage to the high capacity storage battery 5c.
The DC / DC converter 6 further boosts the voltage boosted by the AC / DC converter 8 and applies it to the high-power storage battery 5p.

  The DC / DC converter 6 is a step-up / step-down means. During powering operation of the motor 2, the voltage of the high-capacity storage battery 5c is received and applied to the motor 2 via the inverter 3 after boosting the voltage. During the regenerative operation of 2, the voltage obtained from the motor 2 and the inverter 3 by regeneration is stepped down and applied to the high-capacity storage battery 5c.

The voltage detection device 9 detects the voltage Vo of the external power supply 4 via the AC / DC converter 8 and inputs the detected voltage value to the controller 11.
The current detection device 10 detects the current flowing through the high-power storage battery 5 p and inputs the detected current value to the controller 11.

The controller 11 controls ON / OFF of the switch 7 based on the voltage value and the current value input from the voltage detection device 9 and the current detection device 10.
The switch 7 performs ON / OFF switching of the high-capacity storage battery 5c in response to a command signal from the controller 11.

  That is, when the switch 7 is ON, the high-power storage battery 5p and the high-capacity storage battery 5c are charged. When the switch 7 is OFF, the high-capacity storage battery 5c is disconnected from the circuit. Only the battery is charged.

Next, a control operation during charging from the external power supply 4 to the power storage system 1 will be described with reference to FIG. 2 together with FIG.
FIG. 2 is a flowchart showing a charging control operation when charging the power storage system 1 according to the first embodiment of the present invention from the external power supply 4, and mainly shows the processing operation of the controller 11.

  In FIG. 2, first, the voltage detection device 9 attached to the AC / DC converter 8 detects the voltage Vo of the external power supply 4 and inputs the detected value of the voltage Vo to the controller 11 (step S101).

  The controller 11 determines whether or not the voltage Vo of the external power supply 4 is equal to or higher than 300 [V] (determination reference voltage) (step S102), and if it is determined that Vo ≧ 300 [V] (that is, YES). Then, the switch 7 is turned OFF (step S103), and charging is performed only with the high-power storage battery 5p.

  On the other hand, if it is determined in step S102 that Vo <300 [V] (that is, NO), the controller 11 turns on the switch 7 (step S104), and both the high-power storage battery 5p and the high-capacity storage battery 5c are used. Try to charge.

The reason why the determination reference voltage is set to 300 [V] in step S102 is as follows.
There are two types of charging from the external power source 4; charging from a general household power source with a long charging time and charging from a quick charger. When charging from a general household power source Is charged from the single layer 100 [V] and the single layer 200 [V], and the maximum voltage is about 285 [V] (= 200 [V] × √2).

  On the other hand, when charging from a rapid charging / discharging device with a short charging time, charging is performed at a high voltage of 400 [V] or higher. In such a case (Vo ≧ 300 [V]), a high capacity is obtained. A reference voltage for turning off the switch 7 is set so that the quick charge to the storage battery 5c is not performed.

Finally, it is determined whether or not charging is completed (step S105). If it is determined that charging is completed (that is, YES), the charging process of the power storage system 1 illustrated in FIG.
On the other hand, if it is determined that charging has not been completed (that is, NO), the process returns to step S101, and the charge control process is repeatedly executed (S105).

Next, a control operation during charging / discharging from the motor 2 to the power storage system 1 will be described with reference to FIG. 3 together with FIG. 1.
FIG. 3 is a flowchart showing a charge / discharge control operation when the power storage system 1 according to the first embodiment of the present invention is charged / discharged by the power running / regenerative operation of the motor 2, and mainly shows the processing operation of the controller 11. ing.

In FIG. 3, first, the current detection device 10 attached to the high-power storage battery 5p detects the current Ip flowing through the high-power storage battery 5p, and inputs the detected value of the current Ip to the controller 11 (step S201).
The current Ip flowing through the high-power storage battery 5p indicates whether the power storage system 1 is in a charged state or a discharged state (whether the motor 2 is in a regenerative operation or a power running operation).

  Based on the current Ip (described later), the controller 11 determines whether or not the power storage system 1 is in a charged state (step S202). If it is determined that it is in a discharged state (that is, NO), the switch 7 is turned on. (Step S203), the power running operation of the motor 2 is performed by the power sources of both the high-output storage battery 5p and the high-capacity storage battery 5c.

  On the other hand, if it is determined in step S202 that the power storage system 1 is in a charged state (that is, YES), the controller 11 continues to have a current Ic (calculated value described later) flowing through the high-capacity storage battery 5c equal to or greater than a specified value. It is determined whether or not (step S204).

  If it is determined in step S204 that Ic ≧ specified value (that is, YES), the switch 7 is turned off (step S205), and only the high-power storage battery 5p is charged.

  On the other hand, if it is determined in step S204 that Ic <specified value (that is, NO), the switch 7 is turned on (step S206), and charging is performed with the power sources of both the high-power storage battery 5p and the high-capacity storage battery 5c. To.

Finally, following steps S203, S205, and S206, it is determined whether or not the current Ic flowing through the high-capacity storage battery 5c is 0 (step S207), and if it is determined that Ic = 0 (that is, YES) The charging / discharging process of FIG. 3 is complete | finished.
On the other hand, if it is determined that Ic ≠ 0 (that is, NO), the process returns to step S201, and the charge / discharge control process is repeatedly executed.

  When charging the power storage system 1 from the motor 2 (when regenerating the motor 2), the voltage to the high-capacity storage battery 5c can be set to 50 to 300 [V] by the step-down function of the DC / DC converter 6. Therefore, various control methods can be applied depending on the configuration of the power storage system 1.

Next, a charge / discharge simulation test for the high-power storage battery 5p and the high-capacity storage battery 5c will be described with a specific example.
Here, a lithium ion battery having a rated capacity of 50 [Ah] (nominal voltage 3.6 [V], internal resistance 1 [mΩ]) is used as the high-capacity storage battery 5c, and a rated capacity 5 [Ah] is used as the high-power storage battery 5p. ] (Nominal voltage 3.6 [V], internal resistance 0.1 [mΩ]) lithium ion battery is used.

  Since the voltage range of the high-capacity storage battery 5c can be arbitrarily set in the range of 50 to 300 [V], it is set to 200 [V] as an example here. That is, 56 cells of the high capacity storage battery 5c are connected in series.

  On the other hand, the voltage range of the high-power storage battery 5p can be arbitrarily set in the range of 350 to 400 [V], and is set to 350 [V] as an example here. That is, 98 cells are connected in series to the high-output storage battery 5p.

  When charging from the external power source 4, as described above (steps S102 to S104 in FIG. 2), when Vo <300 [V], the switch 7 is turned on to turn on both the high-power storage battery 5p and the high-capacity storage battery 5c. On the other hand, charging is performed. When Vo ≧ 300 [V], the switch 7 is turned off.

  Further, during the power running operation of the motor 2, as described above (step S203 in FIG. 3), the switch 7 is turned on to supply power from both the high output storage battery 5p and the high capacity storage battery 5c, and during the regenerative operation of the motor 2. Detects the current Ip flowing through the high-power storage battery 5p and calculates the current Ic flowing through the high-capacity storage battery 5c as described above (steps S201 and S204 in FIG. 3).

  The current Ic (maximum current) that flows into the high-capacity storage battery 5c during the regenerative operation of the motor 2 uses the internal resistance Rp of the high-power storage battery 5p, the internal resistance Rc of the high-capacity storage battery 5c, and the regenerative current Im of the motor 2. Is expressed as the following equation (1).

  In addition, when calculated from the JC08 mode (fuel consumption measurement method) which is an automobile travel pattern, since the maximum value of the regenerative current Im of the motor 2 is 60 [A], this value is set as the maximum regenerative current of the motor 2.

In the case of the above configuration, the current Ip (maximum regenerative current) flowing through the high-capacity storage battery 5c is 9 [A] as shown in the equation (1).
The condition when the current Ic flowing through the high-capacity storage battery 5c is less than 0.1 [C] (5 [A]) at the charge rate is the conversion formula of Formula (1) (the formula for obtaining the regenerative current Im of the motor 2). ) And the current Ip flowing through the high-power storage battery 5p, it is expressed as the following formula (2).

  As apparent from the equation (2), the controller 11 controls the switch 7 to be ON when Ic <5 [A], that is, Ip ≦ 28 [A], and Ic ≧ 5 [A], , Ip> 28 [A], it can be seen that the switch 7 is controlled to be OFF.

  Note that the detected value of the current Ip corresponding to the ON / OFF command of the switch 7 needs to be changed according to the rated capacity of the high-capacity storage battery 5c.

  Moreover, in the said simulation test, although the reference value used as ON / OFF instruction | command of the switch 7 was set to 0.1 [C] with the charge rate of the high capacity storage battery 5c, the charge rate depends on the performance of the high capacity storage battery 5c. It can be set arbitrarily depending on the situation.

Next, the effects of the first embodiment of the present invention will be described with reference to FIGS. 4 and 5.
4 and 5 show the effect of improving the life and the effect of shortening the charging time according to Embodiment 1 of the present invention. FIG. 4 is an explanatory diagram showing the capacity retention rate (effect) of the power storage system 1, and FIG. It is explanatory drawing which shows 1 charge time (effect).

4 and 5, the alternate long and short dash line indicates the capacity maintenance rate and the charging time when only the high-capacity storage battery 5c is used, and the solid line indicates that both the high-output storage battery 5p and the high-capacity storage battery 5c are used. The capacity maintenance rate and the charging time of the power storage system 1 are shown.
4 and 5, the capacity maintenance rate and the charging time (one-dot chain line) when the test is performed only with the high-capacity storage battery 5c are shown as comparative examples for clarifying the effect.

  In FIG. 4, according to the comparative example (one-dot chain line), large current charging is performed only on the high-capacity storage battery 5 c during charging by regeneration of the external power supply 4 and the motor 2. The rate decline is large.

  On the other hand, according to Embodiment 1 (solid line) of the present invention, when charging by regeneration of the external power source 4 and the motor 2, in the case of large current charging, charging is performed only with the high output storage battery 5p, and in the case of low current charging. Since charging is performed with both power sources of the high-power storage battery 5p and the high-capacity storage battery 5c, the decrease in the capacity maintenance rate after charging is small.

Moreover, according to Embodiment 1 of this invention, the capacity | capacitance deterioration of the high capacity | capacitance storage battery 5c can be suppressed, and the lifetime improvement of the electrical storage system 1 is attained.
In addition, as shown by the solid line in FIG. 5, rapid charging is possible as compared with the case of charging only the high-capacity storage battery 5c (one-dot chain line). Furthermore, when the external power supply 4 is charged from a quick charger, charging is performed only with the high-power storage battery 5p, thereby enabling further rapid charging as compared with the comparative example (one-dot chain line).

  As described above, power storage system 1 according to Embodiment 1 (FIGS. 1 to 5) of the present invention includes high-power storage battery 5p and high-capacity storage battery 5c connected in parallel to external power supply 4 and motor 2. From the current detection device 10 that detects the current Ip that is attached to the high-output storage battery 5p and flows through the high-output storage battery 5p, the DC / DC converter 6 that controls charging / discharging from the motor 2 to the high-capacity storage battery 5c, and the external power supply 4 AC / DC converter 8 that controls charging to high-output storage battery 5p and high-capacity storage battery 5c, voltage detection device 9 that is attached to AC / DC converter 8 and detects voltage Vo of external power supply 4, and high-capacity storage battery 5c Is connected in series to the switch 7 for disconnecting the high-capacity storage battery 5c from the circuit under predetermined conditions, and the detection values of the voltage detection device 9 and the current detection device 10 are input. As broadcast, and a controller 11 for generating an ON / OFF command for the switch 7, the.

  When the voltage detection device 9 detects a predetermined voltage value or more during external charging from the external power source 4 or when the current detection device 10 detects a predetermined current value or more during regeneration from the motor 2 Generates an OFF command for the switch 7.

  That is, the controller 11 generates an ON command for the switch 7 when the voltage detection device 9 detects less than a predetermined voltage value during external charging from the external power supply 4, and the high output storage battery 5p and the high capacity storage battery. The circuit is configured to perform charging with both storage batteries 5c, and when the voltage detection device 9 detects a predetermined voltage value or more, it generates an OFF command for the switch 7 and charges only with the high-output storage battery 5p. Configure the circuit to do so.

  Further, the controller 11 generates an ON command for the switch 7 when the current detection device 10 detects less than a predetermined current value during regeneration from the motor 2, and the high-power storage battery 5p and the high-capacity storage battery 5c The circuit is configured to perform charging by both storage batteries, and when the current detection device 10 detects a predetermined current value or more, an OFF command for the switch 7 is generated so that charging is performed only by the high-power storage battery 5p. Configure the circuit.

  The high-output storage battery 5p and the high-capacity storage battery 5c are made of lithium ion batteries. The voltage of the high-output storage battery 5p is set within a range of 350 to 450 [V], and the voltage of the high-capacity storage battery 5c is 50 to 300 [ V].

  Furthermore, the charge / discharge control method of power storage system 1 according to Embodiment 1 (FIGS. 1 to 5) of the present invention is a high-power storage battery 5p and a high-capacity storage battery connected in parallel to external power supply 4 and motor 2. 5c, a current detection device 10 for detecting the current Ip flowing through the high-power storage battery 5p, a voltage detection device 9 for detecting the voltage Vo of the external power supply 4, a switch 7 connected in series to the high-capacity storage battery 5c, and voltage detection A controller 11 that performs ON / OFF control of the switch 7 based on the detection values of the device 9 and the current detection device 10 is used.

  The charging / discharging control method for the power storage system 1 according to Embodiment 1 of the present invention includes a step (S101) of detecting the voltage Vo of the external power supply 4 by the voltage detection device 9 during external charging from the external power supply 4, and voltage detection. The step of comparing the value with a predetermined voltage value (S102), and when the detected voltage value indicates less than the predetermined voltage value, the switch 7 is turned on to charge both the high-power storage battery 5p and the high-capacity storage battery 5c by the storage battery. A step of performing (S104), and a step (S103) of performing charging with only the high-power storage battery 5p by controlling the switch 7 to be OFF when the detected voltage value is equal to or higher than a predetermined voltage value.

  Further, at the time of regeneration from the motor 2, a step (S201) of detecting the current Ip of the high-power storage battery 5p by the current detection device 10, a step (S204) of comparing the current detection value with a predetermined current value, and the current detection value When the current value is less than the predetermined current value, when the switch 7 is ON-controlled and charging is performed by both the high-power storage battery 5p and the high-capacity storage battery 5c (S206), and the current detection value indicates the predetermined current value or more And a step (S205) in which the switch 7 is controlled to be OFF and charging is performed only by the high-power storage battery 5p.

Thus, at the time of external charging, the voltage Vo is detected by the voltage detection device 9 connected to the AC / DC converter 8, and in the case of a quick charger with a high voltage detection value, only the high-output storage battery 5p is charged to detect the voltage. In the case of a general household power supply with a low value, both batteries are charged.
Further, during regenerative charging, the current detection device 10 connected to the high output storage battery 5p detects the current generated from the motor 2, and when the current detection value is large, only the high output storage battery 5p is charged and the current detection value is small. If so, charge both batteries.

  According to Embodiment 1 of the present invention, in power storage system 1 using high-output storage battery 5p and high-capacity storage battery 5c, voltage Vo of external power supply 4 during external charging and high-output storage battery 5p during motor regenerative charging When a storage battery that can be charged is selected according to the current Ip, and the detected value indicates a predetermined value or more, the high-capacity storage battery 5c is disconnected from the circuit to suppress deterioration associated with charging / discharging of the high-capacity storage battery 5c. Thus, the life of the power storage system 1 can be extended.

  That is, by disconnecting the high-capacity storage battery 5c, it is possible to prevent deterioration of the high-capacity storage battery 5c at the time of quick charging from the external power source 4 (high output voltage quick charger) or due to a large current supply from the motor 2. At the time of charging from the power supply 4 (rapid charger), further rapid charging can be enabled by charging only with the high-power storage battery 5p.

  Further, by inserting the DC / DC converter 6 between the high-output storage battery 5p and the high-capacity storage battery 5c, the voltage of the high-capacity storage battery 5c can be freely set, and the cell configuration of the high-capacity storage battery 5c can be freely set. Can be designed to.

  Therefore, as shown in FIG. 1, a power storage system 1 having a configuration in which a high-power storage battery 5p and a high-capacity storage battery 5c having different capacity values and resistance values in the power storage system 1 are connected in parallel via a DC / DC converter 6 When applied to an electric vehicle or a plug-in hybrid vehicle, it is possible to prevent a reduction in the life of the power storage system 1 due to rapid charging.

  1 power storage system, 2 motor, 3 inverter, 4 external power supply, 5p high power storage battery, 5c high capacity storage battery, 6 DC / DC converter, 7 switch, 8 AC / DC converter, 9 voltage detection device, 10 current detection device, 11 Controller, Ip Current flowing through the high-power storage battery, Vo external power supply voltage.

Claims (4)

A high-power storage battery and a high-capacity storage battery connected in parallel to an external power source and a motor;
A current detection device that is attached to the high-power storage battery and detects a current flowing through the high-power storage battery;
A DC / DC converter that controls charging and discharging from the motor to the high-capacity storage battery;
An AC / DC converter that controls charging from the external power source to the high-power storage battery and the high-capacity storage battery;
A voltage detection device attached to the AC / DC converter for detecting the voltage of the external power source;
A switch connected in series to the high-capacity storage battery to disconnect the high-capacity storage battery from the circuit under a predetermined condition;
A controller for generating an ON / OFF command for the switch, using detection values of the voltage detection device and the current detection device as input information,
The controller is
When the voltage detection device detects a predetermined voltage value or more during external charging from the external power source, or when the current detection device detects a predetermined current value or more during regeneration from the motor, the switch to generate the OFF command for,
The controller is
During external charging from the external power source,
When the voltage detection device detects less than the predetermined voltage value, the circuit is configured to generate an ON command for the switch and perform charging by both the high-power storage battery and the high-capacity storage battery. ,
An electrical storage system comprising: a circuit configured to generate an OFF command for the switch and perform charging only by the high-power storage battery when the voltage detection device detects the predetermined voltage value or more . The controller is
During regeneration from the motor,
When the current detection device detects less than the predetermined current value, a circuit is configured to generate an ON command for the switch and perform charging by both the high-power storage battery and the high-capacity storage battery. ,
When the current detecting device detects more than the predetermined current value, according to claim 1 which generates an OFF command for said switch, characterized by a circuit to perform charging by only the high-output battery power storage system according to. The high-power storage battery and the high-capacity storage battery are composed of lithium ion batteries,
The voltage of the high power storage battery is set within a range of 350 to 450 [V],
The power storage system according to claim 1 or 2 , wherein the voltage of the high-capacity storage battery is set in a range of 50 to 300 [V]. A high-power storage battery and a high-capacity storage battery connected in parallel to an external power source and a motor;
A current detection device for detecting a current flowing through the high-power storage battery;
A voltage detection device for detecting the voltage of the external power supply;
A switch connected in series to the high-capacity storage battery;
A controller that controls ON / OFF of the switch based on each detection value of the voltage detection device and the current detection device;
A charge / discharge control method for a power storage system using
During external charging from the external power source,
Detecting the voltage of the external power supply by the voltage detection device;
Comparing the voltage detection value with a predetermined voltage value;
When the detected voltage value is less than the predetermined voltage value, the switch is turned on to charge the storage battery of both the high-power storage battery and the high-capacity storage battery; and
When the voltage detection value indicates a predetermined voltage value or more, the switch is turned off and charged only by the high-power storage battery, and
During regeneration from the motor,
Detecting the current of the high-power storage battery by the current detection device;
Comparing the current detection value with a predetermined current value;
When the detected current value is less than the predetermined current value, the switch is turned on to charge the battery by both the high-power storage battery and the high-capacity storage battery;
When the detected current value is equal to or greater than the predetermined current value, the switch is turned off to charge only with the high-power storage battery;
A charge / discharge control method for a power storage system, comprising:

Images