JP3600357B2 - Storage capacitor module - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a storage capacitor module having a built-in storage capacitor such as a large-capacity electric double layer capacitor used for a power storage device of an electric vehicle.
[0002]
[Prior art]
Conventionally, as a power storage device for an electric vehicle, a device mainly including a secondary battery (storage battery) such as a lead storage battery or a nickel cadmium battery has been developed. In parallel with the development of the power storage device using the secondary battery, research on using an extremely large-capacity capacitor (power storage device) called an electric double layer capacitor as a power storage device for an electric vehicle has been advanced.
[0003]
As disclosed in Japanese Patent Application Laid-Open No. 60-15138 and US Pat. No. 3,536,963, this electric double layer capacitor combines activated carbon or activated carbon fiber with an aqueous electrolyte or an organic electrolyte. As a result, an extremely large capacitance is realized. Typically, a capacitor with a large capacity of 5F to 10F is realized under the same diameter and three times the thickness of a ten-yen coin, and is commercially available. Such a large-capacity capacitor has already exceeded that of a lead-acid battery or the like in terms of the amount of electricity stored per unit volume and unit weight, and is therefore extremely promising as a power storage device for electric vehicles. This electric double layer capacitor also has the advantage of being extremely economical in that there is no substantial limitation on the number of times of charging and discharging unlike a storage battery.
[0004]
Conventionally, capacitors (capacitors) have been used alone or in combination with circuit elements such as coils and resistors to realize various AC electrical characteristics such as surge absorption, smoothing, filtering, and tuning. The capacitance is at most several hundred μF, and the stored energy is extremely small even if it is a capacitor. Therefore, a capacitor having a super-large capacity of several tens of farads or more, except for very special applications, is generally used for storing DC power and is distinguished from conventional capacitors for realizing small-capacity AC characteristics. can do. Therefore, in this specification, a capacitor having a large capacity of several tens F or more, such as an electric double layer capacitor for storing DC power, is generically referred to as a "capacitor for power storage".
[0005]
In the case of an electric double layer capacitor which is one of such DC storage capacitors, a typical withstand voltage is as low as several volts. Therefore, in order to realize a power storage device for an electric vehicle having a storage amount of several hundred KWH and an output voltage of about 300 volts, several hundred DC storage capacitors are connected in series and parallel as elements.
[0006]
[Problems to be solved by the invention]
When an electric storage device for an electric vehicle is realized using the electric double layer capacitor, hundreds of capacitor modules are connected in series and in parallel in an array. There is a possibility that the function of the entire apparatus is greatly impaired. In addition, a short circuit may occur due to careless contact between capacitor modules during maintenance and inspection work.
Therefore, an object of the present invention is to provide a capacitor module for a power storage device that does not impair the function of the power storage device as a whole even when a part thereof fails, and that hardly causes a short circuit accident or the like during maintenance and inspection work. Is to do.
[0007]
[Means for Solving the Problems]
The storage capacitor module of the present invention selectively stores a storage capacitor cell such as an electric double layer capacitor, a bypass circuit for the storage capacitor cell, and one of the storage capacitor cell and the bypass circuit. A switch connected to the output terminal, and a control signal input terminal to which a control signal for the switch is supplied. By selectively forming a bypass circuit only in the failed capacitor module, It is configured so that the module can be separated from the capacitor array connected in series and parallel.
[0008]
According to this storage capacitor module, during the period when the supply of the control signal to the switch is stopped, the bypass circuit is closed, and the electric double layer capacitor is disconnected from the output terminal, thereby causing a failure. The voltage is not generated not only at the time of occurrence but also during maintenance and inspection work. In addition, by connecting the control signal line for supplying the control signal to the negative terminal of the storage capacitor cell via discharging means such as a resistor or a capacitor, malfunctions due to static electricity or induced noise can be avoided. Is configured.
[0009]
【Example】
FIG. 1 is an equivalent circuit diagram showing a configuration of a capacitor module according to one embodiment of the present invention, and FIG. 2 is a perspective view showing an appearance of the capacitor module. This capacitor module includes an electric double layer capacitor cell C, positive and negative terminals T1 and T2, and a main circuit MP for connecting the electric double layer capacitor cell C between the positive and negative terminals T1 and T2. A bypass circuit BP, a switch SW for selecting one of the bypass circuit BP and the main circuit MP and connecting to the positive terminal T1, a control signal line CL for supplying a control signal for selection to the switch SW, It has a control terminal CNT for receiving a signal from outside the capacitor module.
[0010]
The capacitor module further includes a resistor R for connecting the control signal line CL to the negative terminal of the electric double layer capacitor cell C, and a voltage for externally monitoring the voltage between the terminals of the electric double layer capacitor cell C. Monitor lines m1 and m2, voltage monitor terminals M1 and M2, a thermocouple TH for detecting the temperature of the electric double layer capacitor cell C, and a voltage for externally monitoring the voltage between the terminals of the thermocouple TH. Voltage monitoring terminals M3 and M4 are provided.
[0011]
As shown in FIG. 3, a specific example of the switch SW shown in FIG. 1 includes high-power field effect transistors FET1 and FET2 and an inverter INV. When a certain level of positive voltage appears on the control signal line CL, the FET1 is turned on and the FET2 is turned off, and the main circuit MP is connected to the positive terminal T1 through the FET1. When a certain level of the positive voltage disappears from the control signal line CL, the FET1 is turned off, the FET2 is turned on, and the bypass circuit BP is connected to the positive terminal T1 through the FET2.
[0012]
The control terminal CNT is kept at zero voltage during the maintenance and inspection work of the electric storage device for an electric vehicle in which a number of the capacitor modules shown in FIGS. 1 and 2 are connected in series and parallel. As a result, the bypass circuit BP is connected between the positive and negative terminals T1 and T2 through the switch SW, and no terminal voltage of the electric double layer capacitor cell C appears between the positive and negative terminals. When the maintenance / inspection work of the electric storage device for an electric vehicle is completed, a constant level positive voltage is supplied from a not-shown electronic control unit (ECU) to the control terminal CNT of each capacitor module. Accordingly, in each capacitor module, the main circuit MP is connected to the positive terminal T1 through the switch SW instead of the bypass circuit BP, and the voltage between the terminals of the electric double layer capacitor cell C is connected between the positive and negative terminals T1 and T2. Appears.
[0013]
During operation of each capacitor module, the terminal voltage and the temperature of the electric double layer capacitor cell C are monitored by an electronic control unit (not shown) through monitor terminals (M1, M2) and (M3, M4). When the electronic control unit determines that an abnormality has occurred in any one of the capacitor modules based on the monitored terminal voltage and operating temperature of each capacitor module, the electronic control unit connects the control terminal CNT of the capacitor module via an external control signal line to the control terminal CNT. To make the constant level of positive voltage being supplied zero.
[0014]
Accordingly, in the capacitor module, the bypass circuit BP is connected to the positive terminal T1 through the switch SW instead of the main circuit MP, and the bypass circuit BP bypasses between the positive and negative terminals T1 and T2. As a result, the capacitor module determined to be faulty is disconnected from the capacitor array in which a number of capacitor modules are connected in series / parallel to constitute a power storage device for an electric vehicle.
[0015]
In order to prevent an unintended positive voltage from appearing at the control terminal CNT due to the generation of static electricity or induced noise, the switch SW is operated, and the control signal line CL and the electric double layer capacitor cell C are used. A resistor R is connected to the main electric circuit MP connected to the negative terminal of the resistor R. The positive voltage appearing on the control signal line CL for a short time due to static electricity, induced noise, or the like is discharged onto the main electric circuit MP through the resistor R and disappears. The same purpose can be achieved by connecting a capacitor having a capacitance of about several tens of μF between the control signal line CL and the main electric circuit MP instead of the resistor.
[0016]
【The invention's effect】
As described in detail above, the capacitor module of the present invention is provided with a bypass circuit and a switch inside the module, and a bypass circuit for a storage capacitor cell such as an electric double layer capacitor cell by a control signal from the outside. In this configuration, only the failed capacitor module can be selectively separated from the capacitor array in which a large number of capacitor modules are connected in series / parallel in order to constitute a power storage device for an electric vehicle. Thus, it is possible to avoid adverse effects on the entire power storage device.
[0017]
In addition, the electric double-layer capacitor cell is disconnected from the output terminal during the period when the control signal is not supplied, such as during maintenance and inspection work of the electric storage device for the electric vehicle , not only when a failure occurs, but also during the work. Short circuit accidents can be effectively prevented. Furthermore, since the control signal line is also connected to the negative terminal of the storage capacitor cell via discharging means such as a resistor or a capacitor, malfunctions due to static electricity, induced noise, and the like are effectively avoided.
[Brief description of the drawings]
FIG. 1 is an equivalent circuit diagram showing a configuration of a capacitor module according to one embodiment of the present invention.
FIG. 2 is a perspective view showing the appearance of the capacitor module of the embodiment.
FIG. 3 is a circuit diagram showing an example of a specific configuration of a switch SW of FIG. 1;
[Explanation of symbols]
C Electric double layer capacitor cell (storage capacitor cell)
T1, T2 Positive / negative terminal MP Main circuit BP Bypass circuit SW Switch CNT Control terminals M1 to M4 Monitor terminals FET1, FET2 Field effect transistor INV Inverter

Claims (3)

An electric double layer capacitor cell, a bypass circuit for disconnecting the electric double layer capacitor cell from the output terminal, a switch for opening and closing the bypass circuit, and a control signal for opening and closing the bypass circuit for the switch. A storage capacitor module having a control signal line
The switch disconnects the electric double layer capacitor cell from the output terminal by closing the bypass circuit during a period in which the supply of the control signal is stopped ;
The power storage capacitor module, wherein the control signal line is also connected to a negative terminal of the power storage capacitor cell via discharging means . In claim 1,
A voltage monitor terminal for monitoring a terminal voltage of the electric double-layer capacitor cell; when an abnormality is determined based on the monitored terminal voltage, supply of the control signal is stopped and the bypass circuit A power storage capacitor module, characterized by being closed . In any one of claims 1 or 2,
A temperature monitor terminal for monitoring the temperature of the electric double layer capacitor cell, and when it is determined that an abnormality has occurred based on the monitored cell temperature, the supply of the control signal is stopped and the bypass circuit is disconnected. A storage capacitor module that is closed .

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