JP2008086175A - Charge/discharge device for battery or electric double-layer capacitor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce the number of required circuit components in a charge/discharge device for executing a charge/discharge test of a battery or an electric double-layer capacitor, and also, to simplify control of the charge/discharge device while facilitating protection of the device from an excessive discharge current. <P>SOLUTION: A PWM converter 11 has a bi-directional power conversion function. An inversion-type step-up/step-down chopper circuit 14 charges a battery 13 from the PWM converter 11 side by turning off a switch S1 after turning it on. The circuit discharges from the battery 13 to the PWM converter 11 side by turning off a switch S2 after turning it on. A charge/discharge voltage and a charge/discharge current are adjusted with each conduction ratio of the switches S1, S2. The charge/discharge device includes a configuration in which a commutator is used instead of the PWM converter and a resistance-type discharge circuit is provided in parallel with the commutator. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a charge / discharge device for performing tests such as charge / discharge characteristics and life evaluation of a battery or an electric double layer capacitor, and more particularly to a device for controlling a charge / discharge current by a chopper operation of a semiconductor switch.

  FIG. 3 shows a main circuit configuration of the regenerative charge / discharge device (see, for example, Patent Document 1). The PWM converter 1 is a bidirectional power converter having a forward conversion function for obtaining voltage-controlled DC power from the AC power supply AC and an inverse conversion function for regenerating DC power to the AC power supply AC. The smoothing capacitor 2 smoothes the DC output for the forward conversion operation of the PWM converter 1 and becomes a DC power source for the reverse conversion operation. Note that the PWM converter 1 may be configured in two units in which a forward converter and an inverse converter (inverter) are connected in parallel. The four-quadrant chopper circuit (bridge-type reversible chopper circuit) 3 has a configuration in which four arms are bridge-connected by a basic arm 3A and a control arm 3B, and among the arms, the arms at diagonal positions are complementary arms. Become. Each of the arms 3A and 3B has a configuration in which semiconductor switches S1 to S4 and diodes D1 to D4 are connected in antiparallel to the semiconductor switches S1 to S4, respectively. A DC reactor 4 and a battery (electric double layer capacitor, capacitor, etc.) 5 to be tested are connected between the connection points of the upper and lower arms of the arms 3A and 3B.

  In this configuration, when the battery 5 is discharged, the switches S2 and S3 are turned on so that a discharge current flows to the battery 5 through the DC reactor 4 and then the switch S3 is turned off to turn off the switch S2 and the diode. A discharge current due to the circulating current is caused to flow through the path D4, and then the switch S2 is turned off to cause the circulating current to flow as a discharge current to the DC power source via the paths of the diodes D1 and D4.

Further, when charging the battery 5, by turning on the switches S1 and S4, a charging current is caused to flow from the DC power source to the battery 5, and thereafter, by turning off the switch S1, a circulating current is caused to flow through the path of the switch S4 and the diode D2. Thereafter, the switch S4 is turned off to allow the circulating current to flow as a discharge current to the DC power source through the diodes D2 and D3.
JP 2001-16798 A

  Since the conventional charging / discharging device employs a four-quadrant chopper circuit, it requires four semiconductor switches S1 to S4, and further uses the PWM converter 1 for the DC power supply. Becomes complicated and expensive.

  In addition, a rectifier may be used in place of the PWM converter 1 and the discharge test of the battery 5 may be provided with a discharge circuit of a series connection configuration of a discharge resistor and a semiconductor switch in the DC power supply. A circuit state in which an excessive current flows in the discharge circuit when the discharge current is large is expected, and a circuit for protecting the discharge circuit and the semiconductor switches S1 to S4 and the diodes D1 to D4 from the excessive current is also required. In addition, a circuit breaker having a large DC breaking capacity is also required when the function of interrupting the discharge is provided for the generation of an excessive current.

  An object of the present invention is to provide a charging / discharging device for a battery or an electric double layer capacitor that can reduce the number of necessary circuit components and simplify the control thereof, and can easily protect against excessive discharge current. .

  The present invention for solving the above-described problems is characterized by the following configuration.

(1) A charge / discharge device for performing a charge / discharge test of a battery or an electric double layer capacitor,
Bidirectional power converter capable of forward conversion to obtain DC power from an AC power supply and reverse conversion to regenerate power from the DC power supply to the AC power supply,
A semiconductor switch and a pair of arms composed of diodes connected in reverse parallel to the semiconductor switch, and a direct current reactor, provided between the bidirectional power converter and the battery or electric double layer capacitor, and a chopper of the semiconductor switch An inverting buck-boost chopper circuit that performs charge control and discharge control between the AC power source and the battery or the electric double layer capacitor through the power converter by operation;
It is provided with.

(2) A charge / discharge device for performing a charge / discharge test of a battery or an electric double layer capacitor,
A rectifier that obtains DC power from an AC power supply;
A discharge circuit provided on the output side of the rectifier in a series connection of a semiconductor switch and a discharge resistor;
A semiconductor switch and a pair of arms composed of diodes connected in reverse parallel to the semiconductor switch, and a direct current reactor, provided between the bidirectional power converter and the battery or electric double layer capacitor, and a chopper of the semiconductor switch Inverting step-up / step-down chopper that performs charging control between the AC power source and the battery or the electric double layer capacitor through the rectifier by operation and discharging control between the discharge circuit and the battery or the electric double layer capacitor. Circuit,
It is provided with.

  As described above, according to the present invention, charge control from an AC power supply to a battery or an electric double layer capacitor and discharge control from a battery or electric double layer capacitor to an AC power supply or discharge circuit are performed by an inverting buck-boost chopper circuit. As a result, the required number of circuit components can be reduced and control thereof can be simplified, and protection from excessive discharge current can be facilitated.

(Embodiment 1)
FIG. 1 is a main circuit configuration diagram of a charging / discharging device showing the present embodiment. As in FIG. 3, the PWM converter 11 has a forward conversion function and an inverse conversion function, and constitutes a DC power source in combination with the smoothing capacitor 12. An inverting step-up / step-down chopper circuit 14 is provided between a battery (or electric double layer capacitor) 13 serving as a device under test and a DC power source of the PWM converter 11.

  The inverting step-up / down chopper circuit 14 includes semiconductor switches S1 and S2, a series connection circuit of a pair of arms in which diodes D1 and D2 are connected in antiparallel, and a connection point between both arms and a reference potential. The DC reactor L is connected.

  The connection polarity of the semiconductor switches S1 and S2 is the direction in which forward current flows from the P pole of the DC power source to the battery 13. The battery 13 has a negative electrode (−) terminal connected to the arm output terminal side of the chopper circuit 14 and a positive electrode (+) terminal connected to the reference potential side.

  In this configuration, when the battery 13 is charged, the semiconductor switch S1 is turned on while the semiconductor switch S2 is turned off, so that the semiconductor switch S1 → DC reactor L → N pole is changed from the P pole of the DC power supply of the PWM converter 11. A short circuit current is passed through the path. After that, by turning off the semiconductor switch S1 within a time when the DC reactor L is not saturated, a circulating current is passed from the DC reactor L to the battery 13 through the path of the battery 13 to the diode D2, and stored in the DC reactor L. The battery 13 is charged with electric energy.

  In such a charging operation, a charging current is passed through the battery 13 by the switching operation (on / off repetition) of the semiconductor switch S1, and the charging voltage and current at the time of charging are the ON / OFF ratio (conductivity) of the semiconductor switch S1. And can be adjusted by controlling the output voltage of the PWM converter 11.

  Next, when the battery 13 is discharged, the semiconductor switch S2 is turned on while the semiconductor switch S1 is turned off, so that a short-circuit current flows from the battery 13 through the path of the DC reactor L → the semiconductor switch S2. Thereafter, by turning off the semiconductor switch S2 within a time period when the DC reactor L is not saturated, a circulating current is caused to flow from the DC reactor L through the diode D1 → PWM converter 11 and the electric energy stored in the DC reactor L is reduced. Regenerate to AC power supply AC side.

  In such a discharge operation, a discharge current is caused to flow from the battery 13 by the switching operation (on / off repetition) of the semiconductor switch S2, and the discharge voltage and current at the time of discharge are the on / off ratio (conductivity) of the semiconductor switch S2. And can be adjusted by controlling the output voltage of the PWM converter 11.

  According to the present embodiment, the required number of arms formed of semiconductor switches and antiparallel diodes can be reduced by half compared to the configuration of FIG. In addition, the control circuit of the semiconductor switch can be simplified. Furthermore, the semiconductor switches S1. Since the charge / discharge current can be adjusted by the continuity of S2, charge / discharge control by the PWM converter is unnecessary, and the control device is simplified.

  In this embodiment, the PWM converter can obtain the same operation and effect as a bidirectional power converter having a parallel connection configuration of a forward converter and an inverse converter.

(Embodiment 2)
FIG. 2 is a main circuit configuration diagram of the charging / discharging device showing the present embodiment. 1 is different from FIG. 1 in that a rectifier 15 and a resistive discharge circuit 16 are provided in place of the PWM converter 11.

  The rectifier 15 has only a rectifying function for converting AC power of the AC power source AC into DC power, and constitutes a DC power source in combination with the smoothing capacitor 12. A semiconductor switch SW1 is provided between the rectifier 15 and the AC power supply AC, and the circuit between them can be interrupted. The resistance type discharge circuit 16 has a discharge resistor R and a semiconductor switch SW2 connected in series, and is provided in parallel with a DC power source.

  In this configuration, the battery 13 is charged when the semiconductor switch SW1 is turned on and the SW2 is turned off, the semiconductor switch S2 is turned off, and the semiconductor switch S1 is switched to obtain the same charging operation as in FIG. .

  When the battery 13 is discharged, the semiconductor switch SW1 is turned off, the switch SW2 is turned on, the semiconductor switch S1 is turned off, and the semiconductor switch S2 is turned on, so that the battery 13 is connected to the DC reactor L → the semiconductor switch S2. Apply short circuit current. Thereafter, by turning off the semiconductor switch S2 within a time period when the DC reactor L is not saturated, a circulating current flows from the DC reactor L through the path of the diode D1, the switch SW2, and the discharge resistance R, and the DC reactor L is stored. Electric energy is discharged as heat by the discharge resistor R.

  In this discharge operation, the discharge voltage and the discharge current can be adjusted by the semiconductor switch S2, and even when the charging energy of the battery 13 is large, an excessive current does not flow to the discharge circuit, and the semiconductor switches SW2, S1 and the diode D1 can be protected from overcurrent.

  According to the present embodiment, in addition to the effects of the first embodiment, an expensive PWM converter becomes unnecessary.

The main circuit block diagram which shows Embodiment 1 of this invention. The main circuit block diagram which shows Embodiment 2 of this invention. The main circuit block diagram of the conventional regenerative charging / discharging apparatus.

Explanation of symbols

1,11 PWM converter 2,12 Smoothing capacitor 5,13 Battery (or electric double layer capacitor)
14 Inverting Buck-Boost Chopper 15 Rectifier 16 Resistive Discharge Circuit

Claims (2)

A charge / discharge device for performing a charge / discharge test of a battery or an electric double layer capacitor,
Bidirectional power converter capable of forward conversion to obtain DC power from an AC power supply and reverse conversion to regenerate power from the DC power supply to the AC power supply,
A semiconductor switch and a pair of arms composed of diodes connected in reverse parallel to the semiconductor switch, and a direct current reactor, provided between the bidirectional power converter and the battery or electric double layer capacitor, and a chopper of the semiconductor switch An inverting buck-boost chopper circuit that performs charge control and discharge control between the AC power source and the battery or the electric double layer capacitor through the power converter by operation;
A battery or an electric double layer capacitor charging / discharging device comprising: A charge / discharge device for performing a charge / discharge test of a battery or an electric double layer capacitor,
A rectifier that obtains DC power from an AC power supply;
A discharge circuit provided on the output side of the rectifier in a series connection of a semiconductor switch and a discharge resistor;
A semiconductor switch and a pair of arms composed of diodes connected in reverse parallel to the semiconductor switch, and a direct current reactor, provided between the bidirectional power converter and the battery or electric double layer capacitor, and a chopper of the semiconductor switch Inverting step-up / step-down chopper that performs charging control between the AC power source and the battery or the electric double layer capacitor through the rectifier by operation and discharging control between the discharge circuit and the battery or the electric double layer capacitor. Circuit,
A battery or an electric double layer capacitor charging / discharging device comprising:

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