JP2003199203A - Protection method for regenerated-energy accumulator and regenerated-energy accumulator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a protection technique for a regenerated-energy accumulator that uses an electric double-layer capacitor for protecting the regenerated- energy accumulator, particularly for a regenerated-energy accumulating means. <P>SOLUTION: The accumulator comprises: an inverter 1 that converts a DC to an AC; a motor load 2 that is driven by the inverter; a DC capacitor 3 that controls the instantaneous ripple of a DC input voltage of the inverter; a DC power source 5; the regenerated-energy accumulating means 6; a DC/DC converter 7 that connects the regenerated-energy accumulating means and the DC input of the inverter; and a conduction ratio control means 8 that controls the conduction ratio of the DC/DC converter. The DC input voltage of the inverter 1 is detected, and, when the detected voltage exceeds a prescribed level, the conduction ratio of the DC/DC converter is changed so as to raise a charge current to the regenerated-energy accumulating means, thus protecting the inverter, DC/DC converter and regenerated-energy accumulating means. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for protecting a regenerative energy storage device and a regenerative energy storage device.

[0002]

2. Description of the Related Art In recent years, electric double layer capacitors (EDL)
C: Electric Double Layer Capacitor) is receiving attention. An electric double layer is a state in which when two different phases such as a solid and a liquid come into contact with each other, positive and negative charges are present at the boundary surface with a molecular level distance. The electric double layer capacitor uses the electric double layer as the function of the dielectric instead of the dielectric of the capacitor.

Its characteristics are: rapid charge / discharge is possible, large output density, no chemical reaction, so little deterioration due to repeated charge / discharge, long life, maintenance-free, charge / discharge The efficiency is high. ・ The amount of stored electricity can be known from the voltage and it is easy to control. ・ The components are pollution-free and there is no risk of material depletion.

Such an electric double layer capacitor can be widely used as a power source or auxiliary power source for electric vehicles, railways, ships, etc., and can be used as a secondary battery for storing regenerative energy.

[0005]

However, although the electric double layer capacitor has such technically excellent characteristics as described above, the conventional technique has been focused on the development of its application, and the technology focused on its protection technique has been paid attention to. Is not known.

In view of such a conventional technical background, the present invention provides a protection technique for a regenerative energy storage device, and more particularly, a protection technique for a regenerative energy storage device using an electric double layer capacitor as a regenerative energy storage means. To aim.

[0007]

According to a first aspect of the present invention, there is provided an inverter for converting direct current into alternating current, a motor load driven by the inverter, and a direct current capacitor for suppressing instantaneous ripple of direct current input voltage of the inverter. , A DC source, a regenerative energy storage means, and a DC / connecting the regenerative energy storage means and the DC input of the inverter.
A method for protecting a regenerative energy storage device comprising a DC converter and a duty ratio control means for controlling the duty ratio of the DC / DC converter, wherein a DC input voltage of the inverter is detected, and the detected voltage is a set level. By exceeding the above condition, the flow rate of the DC / DC converter is changed in the direction of increasing the charging current to the regenerative energy storage means.

According to a second aspect of the present invention, in the protection method for the regenerative energy storage device according to the first aspect, the DC input voltage of the inverter is detected, and when the detected voltage exceeds a set level, the DC / DC converter is protected. It is characterized by increasing the flow rate.

According to a third aspect of the present invention, in the method of protecting a regenerative energy storage device according to the first aspect, the DC / DC converter is a chopper type, the DC input voltage of the inverter is detected, and the detected voltage is set at a set level. When it exceeds the limit, all the switching elements on the side for supplying the charging current to the regenerative energy storage means of the DC / DC converter are turned on.

According to a fourth aspect of the present invention, an inverter for converting direct current into alternating current, a motor load driven by the inverter, a direct current capacitor for suppressing instantaneous ripple of direct current input voltage of the inverter, a direct current source, and a regenerative power source. Energy storage means, a DC / DC converter that connects the regenerative energy storage means and the DC input of the inverter,
From the conduction ratio control means for controlling the conduction ratio of the DC / DC converter, the power switch provided at the output end of the DC source, and the discharge resistance and the discharge resistance switch provided in parallel with the DC capacitor. A method of protecting a regenerative energy storage device comprising: detecting a DC input voltage of the inverter, wherein the detected voltage exceeds a set level,
The DC / DC converter is gate-blocked, the power switch is turned off, and the discharge resistance switch is turned on.

According to a fifth aspect of the present invention, an inverter for converting direct current into alternating current, a motor load driven by the inverter, a direct current capacitor for suppressing instantaneous ripple of the direct current input voltage of the inverter, a direct current source, and regenerative energy storage. Means, a DC / DC converter for connecting the regenerative energy storage means and the DC input of the inverter, and the DC
A duty ratio control means for controlling the duty ratio of the DC / DC converter, a power switch provided at an output end of the DC source,
A method for protecting a regenerative energy storage device comprising a discharge resistance and a discharge resistance switch provided in parallel with the direct current capacitor, and a terminal switch provided at an input / output terminal of the regenerative energy storage means, the direct current of the inverter being An input voltage is detected, and when the detected voltage exceeds a set level, the DC / DC converter is gate-blocked, the power switch is turned off, the terminal switch is turned off, and the discharge resistance switch is turned on. Is characterized by.

According to a sixth aspect of the present invention, an inverter for converting direct current into alternating current, a motor load driven by the inverter, a direct current capacitor for suppressing instantaneous ripple of the direct current input voltage of the inverter, a direct current source, and regenerative energy storage. Means, a DC / DC converter that connects the regenerative energy storage means and the DC input of the inverter, a brake resistance and a brake resistance switch that are provided in parallel with the DC capacitor, and a conduction ratio of the brake resistance switch. A method for protecting a regenerative energy storage device comprising a switch conduction ratio control means for controlling, wherein a DC input voltage of the inverter is detected, and when the detected voltage exceeds a set level, the brake resistance switch is activated. The rate is controlled so that the DC input voltage decreases.

According to a seventh aspect of the present invention, an inverter for converting direct current into alternating current, a motor load driven by the inverter, a direct current capacitor for suppressing instantaneous ripple of the direct current input voltage of the inverter, a direct current source, and regenerative energy storage. Means, a DC / DC converter that connects the regenerative energy storage means and the DC input of the inverter, and the D
A conduction ratio control means for controlling the conduction ratio of the C / DC converter, a brake resistance and a brake resistance switch provided in parallel with the DC capacitor, and a switch conduction ratio for controlling the conduction ratio of the brake resistance switch. A method for protecting a regenerative energy storage device comprising a control means, wherein a DC input voltage of the inverter is detected, and when the detected voltage exceeds a set level, the conduction ratio of the brake resistance switch is changed to the DC input voltage. Is controlled so as to decrease, and the DC / DC converter is gate-blocked.

The invention of claim 8 is the invention of claims 1, 2, 4-7.
The method of protecting a regenerative energy storage device according to
The C / DC converter is a chopper type converter.

The invention of claim 9 relates to claim 1, 2, 4-7.
The method for protecting a regenerative energy storage device according to any one of 1 to 3, wherein the DC / DC converter is a high frequency insulation type converter.

According to a tenth aspect of the present invention, in the method for protecting the regenerative energy storage device according to the first to ninth aspects, a capacitor is provided between the terminals of the regenerative energy storage means.

The invention of claim 11 is the method for protecting a regenerative energy storage device according to claims 1 to 10, wherein the regenerative energy storage means is a secondary battery.

According to a twelfth aspect of the present invention, in the method for protecting the regenerative energy storage device according to the first to tenth aspects, the regenerative energy storage means is an electric double layer capacitor.

A regenerative energy storage device according to a thirteenth aspect of the present invention includes an inverter for converting direct current into alternating current, a motor load driven by the inverter, and a direct current capacitor for suppressing instantaneous ripple of direct current input voltage of the inverter. A DC source for supplying DC power to the inverter, a regenerative energy storage means, a DC / DC converter connecting the regenerative energy storage means and a DC input of the inverter, and voltage detection for detecting a DC input voltage of the inverter. And a detection rate of the voltage detector exceeds a set level, the conduction rate of the DC / DC converter is controlled so as to change the conduction rate of the DC / DC converter in a direction of increasing the charging current to the regenerative energy storage means. And a control means.

According to a fourteenth aspect of the present invention, in the regenerative energy storage device according to the thirteenth aspect, the conduction ratio control means is configured to detect the DC / DC by the detected voltage of the DC input voltage of the inverter exceeding a set level. It is characterized in that control is performed to increase the flow rate of the converter.

According to a fifteenth aspect of the present invention, in the regenerative energy storage device according to the thirteenth aspect, the DC / DC converter is a chopper type, and the conduction ratio control means sets a detection voltage of a DC input voltage of the inverter. When the voltage exceeds the level, control is performed to turn on all the switching elements on the side for supplying the charging current to the regenerative energy storage means of the DC / DC converter.

According to a sixteenth aspect of the present invention, there is provided a regenerative energy storage device including an inverter for converting direct current into alternating current, a motor load driven by the inverter, and a direct current capacitor for suppressing instantaneous ripple of direct current input voltage of the inverter. A DC source for supplying DC power to the inverter, a regenerative energy storage means, a DC / DC converter connecting the regenerative energy storage means and a DC input of the inverter, and a power supply provided at an output end of the DC source. A switch, a discharge resistance and a discharge resistance switch provided in parallel with the DC capacitor, a voltage detector for detecting a DC input voltage of the inverter, and a detection voltage of the voltage detector exceeding a set level, Gate block the DC / DC converter, turn off the power switch, and discharge the discharge resistor. In which a control means for turning on the switch.

According to a seventeenth aspect of the present invention, in the regenerative energy storage device, an inverter for converting direct current into alternating current, a motor load driven by the inverter, a direct current capacitor for suppressing instantaneous ripple of the direct current input voltage of the inverter, and the inverter. A direct current source for supplying direct current power, a regenerative energy storage means, a DC / DC converter connecting the regenerative energy storage means and the direct current input of the inverter, and a power switch provided at the output end of the direct current source. ,
A discharge resistance and a discharge resistance switch provided in parallel with the DC capacitor, a terminal switch provided at an input / output terminal of the regenerative energy storage means, a voltage detector for detecting a DC input voltage of the inverter, and the voltage. When the detection voltage of the detector exceeds the set level, the DC
And a control means for gate-blocking the / DC converter, turning off the power switch, turning off the terminal switch, and turning on the discharge resistance switch.

According to another aspect of the present invention, there is provided a regenerative energy storage device including an inverter for converting direct current into alternating current, a motor load driven by the inverter, a direct current capacitor for suppressing instantaneous ripple of the direct current input voltage of the inverter, and the inverter. A DC source for supplying DC power to the regenerative energy storage means, a regenerative energy storage means, a DC / DC converter connecting the regenerative energy storage means to the DC input of the inverter, and a brake resistor and a brake provided in parallel with the DC capacitor. A resistance switch, a voltage detector for detecting a DC input voltage of the inverter, and a detection voltage of the voltage detector exceeding a set level, whereby the DC input voltage lowers the conduction ratio of the brake resistance switch. And a switch conduction ratio control means for controlling the direction.

According to a nineteenth aspect of the present invention, in the regenerative energy storage device, an inverter for converting direct current into alternating current, a motor load driven by the inverter, a direct current capacitor for suppressing instantaneous ripple of the direct current input voltage of the inverter, and the inverter. A DC source for supplying DC power to the regenerative energy storage means, a regenerative energy storage means, a DC / DC converter connecting the regenerative energy storage means to the DC input of the inverter, and a brake resistor and a brake provided in parallel with the DC capacitor. A resistance switch, a voltage detector for detecting a DC input voltage of the inverter, and a detection voltage of the voltage detector exceeding a set level, whereby the DC input voltage lowers the conduction ratio of the brake resistance switch. Control means for controlling the direction and controlling the gate of the DC / DC converter. It includes those were.

The invention of claim 20 is the invention of claims 13, 14,
In the regenerative energy storage device of 16 to 19, the D
The C / DC converter is a chopper type converter.

The invention of claim 21 relates to claim 13, 14,
In the regenerative energy storage device of 16 to 19, the D
The C / DC converter is a high frequency isolated converter.

According to a twenty-second aspect of the present invention, in the regenerative energy storage device according to the thirteenth to twenty-first aspects, a capacitor is provided between the terminals of the regenerative energy storage means.

A twenty-third aspect of the present invention is the regenerative energy storage device according to the thirteenth to the twenty-second aspects, wherein the regenerative energy storage means is a secondary battery.

The invention of claim 24 is the regenerative energy storage device according to claims 13 to 22, wherein the regenerative energy storage means is an electric double layer capacitor.

[0031]

BEST MODE FOR CARRYING OUT THE INVENTION The regenerative energy storage device of the present invention is used to store DC power generated by a power generator or to store regenerative energy of a load, and is particularly useful for railways, electric vehicles, elevators and ships. It can be used as a DC power source, auxiliary power source, regenerative power storage device, etc.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 shows a circuit configuration of a regenerative energy storage device according to a first embodiment of the present invention. The regenerative energy storage device of the present embodiment includes an inverter 1 that converts direct current into alternating current, a motor load 2 that is driven by this inverter 1, a direct current capacitor 3 that suppresses instantaneous ripple of the direct current input voltage of the inverter 1. The reactor 4, the DC source 5 for supplying DC power to the inverter 1, the regenerative energy storage means 6, the DC / DC converter 7 connecting the regenerative energy storage means 6 and the DC input of the inverter 1, and the inverter 1. A voltage detector 8 for detecting a DC input voltage, a current detector 9 for detecting a current flowing through a connection line between the regenerative energy storage means 6 and the DC / DC converter 7, and a conduction ratio of the DC / DC converter 7 are controlled. The flow rate controller 10 is configured.

The regenerative energy storage means 6 may be a lead storage battery, a lithium ion storage battery or other secondary battery as shown in FIG. 12, and an electric double layer capacitor as shown in FIG. Can be used. However, especially when an electric double layer capacitor is used, the protection control described later is particularly effective due to its electrical characteristics.

Further, as shown in FIG. 14, a capacitor 11 is provided between the terminals of the regenerative energy storage means 6, and a DC / DC converter 7 is connected between these terminals,
The followability of the regenerative energy storage means 6 side with respect to the charge / discharge operation of the DC / DC converter 7 operating at high frequency can be compensated.

The DC / DC converter 7 includes a charging side switching element Q1 and a diode D as shown in FIG.
1. A chopper type converter including a discharge side switching element Q2, a diode D2, a reactor L and a capacitor C can be adopted, or a general high frequency insulation type converter can be used.

Next, the operation of the regenerative energy storage device of the first embodiment having the above configuration will be described. Normally, after removing the ripple component of the DC power of the DC source 5 by the reactor 4 and the DC capacitor 3, the DC power is input to the DC input terminal of the inverter 1, and the DC
Alternating current is converted into alternating current power having a predetermined frequency and a predetermined voltage and supplied to the motor load 2.

When the direct current source 5 is cut off or its voltage drops, the regenerative energy storage means 6 is used as a direct current source, and the direct current of the inverter 1 is converted to direct current of a predetermined voltage by the DC / DC converter 7. It is supplied to the input terminal, converted into DC-AC by the inverter 1, converted into AC power having a predetermined frequency and a predetermined voltage, and supplied to the motor load 2.

On the other hand, when regenerative electric power is generated in the motor load 2, the inverter 1 acts as a converter,
The AC power of the motor load 2 is AC-DC inversely converted and output to the DC end side. As a result, if the DC input voltage of the inverter 1 detected by the voltage detector 8 rises, DC / D
The C converter 7 converts DC power into DC / DC, and stores the regenerative current in the regenerative energy storage means 6.

The DC / DC converter 7 turns on / off the switching element in the direction of charging the regenerative energy storage means 6 (referred to as “forward direction”) by the conduction ratio control section 10 and in the direction of discharging from the switching element 6 ( It controls the on / off conduction ratios of the switching elements in the "negative direction"), and regenerates the regenerative current applied to the output side terminal (the right side terminal in FIG. 1) of the DC / DC converter 7. The period during which the energy storage means 6 is charged, and also the input terminal of the converter 7 (the terminal on the regenerative energy storage means 6 side)
The period of time during which the regenerative energy storage means 6 applied to the output terminal outputs current from the output terminal side is controlled. And
This flow rate control is performed by the regenerative energy storage means 6 and DC /
This is performed based on the detection value of the current detector 9 that detects the current flowing through the connection line with the DC converter 7.

The method of controlling the current flow rate is based on the method which has been conventionally carried out when the regenerative energy storage means 1 is a secondary battery. Further, in the present specification, “gate block” refers to completely stopping the operation of the DC / DC converter 7. Further, "all ON" of the switching elements in the chopper type converter means a state in which all the switching elements that flow a current in the charging direction with respect to the regenerative energy storage means 6 are turned on and all the switching elements that flow a current in the discharging direction are all turned off. .

In the present embodiment, the flow rate control unit 10 further has a function as shown in the timing chart of FIG.
The voltage across the DC capacitor 3, that is, the DC input voltage of the inverter 1 is monitored by the voltage detector 8, and when a voltage exceeding a preset level R1 determined by an experiment occurs, the DC / DC converter 7 The control is performed to increase the conduction ratio, the charging current regenerated in the regenerative energy storage unit 6 is increased, and the protection control for suppressing the rise of the DC input voltage of the inverter 1 is performed.

As a result, in the regenerative energy storage device and the protection method therefor of the first embodiment, if the regenerative energy becomes large and the DC input voltage of the inverter 1 becomes high enough to exceed the set level R1, DC / DC is set. By controlling the conduction ratio of the converter 7 in the direction of increasing the charging current regenerated in the regenerative energy storage means 6 through the converter 7, it is possible to suppress the occurrence of overvoltage on the DC input side of the inverter 1, The DC / DC converter 7 is protected. In particular, the regenerative energy storage means 6
When the electric double layer capacitor is adopted in the above, its characteristic allows quick absorption of regenerative energy and effective suppression of the DC input voltage.

Next, a regenerative energy storage device according to a second embodiment of the present invention will be described with reference to FIGS. 1 and 3. The circuit configuration of the regenerative energy storage device according to the second embodiment is similar to that of the first embodiment, and is the one shown in FIG. The characteristic of the second embodiment is the protection operation.

That is, the conduction ratio control unit 10 monitors the voltage detected by the voltage detector 8, and when it reaches a predetermined set level R2 determined by an experiment in advance, the conduction ratio control unit 10 controls the DC voltage. By turning on all the conduction ratios of the / DC converter 7, a large amount of current is made to flow to the regenerative energy storage means, the DC input voltage of the inverter 1 is rapidly lowered, and an overvoltage is generated at the DC input side of the inverter 1. To protect the inverter 1 and the DC / DC converter 7. In particular, when the electric double layer capacitor is adopted as the regenerative energy storage means 6, the regenerative energy can be absorbed quickly due to its characteristics, and therefore the overvoltage of the DC input voltage can be effectively prevented.

The protection methods of the first embodiment and the second embodiment are combined to increase the conduction ratio of the DC / DC converter 7 when the DC input voltage of the inverter 1 reaches the set level R1. The DC / DC is controlled when the DC input voltage reaches the set level R2 (> R1).
It is also possible to adopt a two-stage protection method in which all the converters 7 are turned on to rapidly reduce the DC input voltage.

Next, a regenerative energy storage device according to a third embodiment of the present invention will be described with reference to FIGS. 4 and 5. The feature of the third embodiment is that, in addition to the circuit configuration of the first embodiment shown in FIG. 1, a power switch 12 and a DC capacitor 3 are connected in parallel to the output terminal of the DC source 5. Discharge resistance 13 and discharge resistance switch 1 provided
4 and a switch control unit 15 for controlling on / off of the discharge resistance switch 14 according to the detection voltage of the voltage detector 8.

Next, the operation of the regenerative energy storage device of the third embodiment will be described. The normal operation of the regenerative energy storage device of the third embodiment is the same as that of the first embodiment, but the protective operation is performed as follows.

The conduction ratio control unit 10 monitors the voltage detected by the voltage detector 8, and when the conduction ratio control unit 10 reaches a predetermined set level R3 determined by an experiment in advance, the conduction ratio control unit 1
By 0, the DC / DC converter 7 is gate-blocked and stopped to prevent regenerative energy from flowing to the regenerative energy storage means. Along with this, the switch control unit 1
5 also monitors the detection voltage of the voltage detector 8, and when the set level R3 is reached, the power switch 12 is turned off,
By turning on the discharge resistance switch 14, a direct current is consumed by the discharge resistance 13.

As a result, in the regenerative energy storage device of the third embodiment, the DC input voltage of the inverter 1 is rapidly lowered to the voltage of the regenerative energy storage means 6 to protect the inverter 1 and the DC / DC converter 7 from overvoltage. It is also possible to prevent the excessive regenerative current from flowing into the regenerative energy storage means 6. In particular,
When the electric double layer capacitor is adopted as the regenerative energy storage means 6, it is effective in protecting the regenerative energy storage means 1 having a fast response.

Next, a regenerative energy storage device according to a fourth embodiment of the present invention will be described with reference to FIGS. 6 and 7. The feature of the fourth embodiment is that, in addition to the circuit configuration of the third embodiment shown in FIG. 4, a terminal switch 16 is further provided at the terminal of the regenerative energy storage means 6, and the switch control unit 15 is provided. There is a point that the on / off control is performed by. In the block diagram of FIG. 6, components common to those of the circuit components of FIG. 4 are designated by the same reference numerals.

The normal operation of the regenerative energy storage device of the above-mentioned fourth embodiment is the same as that of the first embodiment. The protection operation when the DC input voltage of the inverter 1 exceeds the set level R4 is as follows.

As in the third embodiment, the conduction ratio control section 10 monitors the voltage detected by the voltage detector 8 and has a predetermined set level R4 (this set level is determined by experiment) in advance. R4 can be set equal to R3, but when it reaches the appropriate value determined by the experiment), the DC / DC converter 7 is gate-blocked by the conduction ratio controller 10. It is stopped so that regenerative energy does not flow to the regenerative energy storage means.

At the same time, the switch control unit 15 also monitors the detection voltage of the voltage detector 8, and when the set level R3 is reached, the power switch 12 is turned off and the discharge resistance switch 14 is turned on. The current is consumed by the discharge resistor 13, and the terminal switch 16 of the regenerative energy storage means 6 is turned off.

As a result, in the regenerative energy storage device of the fourth embodiment, the DC input voltage of the inverter 1 is rapidly lowered to the voltage of the regenerative energy storage means 6 to protect the inverter 1 and the DC / DC converter 7 from overvoltage. It is also possible to prevent the excessive regenerative current from flowing into the regenerative energy storage means 6. In particular,
When the electric double layer capacitor is adopted as the regenerative energy storage means 6, it is effective in protecting the regenerative energy storage means 1 having a fast response.

Next, a regenerative energy storage device according to a fifth embodiment of the present invention will be described with reference to FIGS. 8 and 9. The regenerative energy storage device of the present embodiment includes an inverter 1 that converts direct current into alternating current, a motor load 2 that is driven by this inverter 1, a direct current capacitor 3 that suppresses instantaneous ripple of the direct current input voltage of the inverter 1. The reactor 4, the DC source 5 for supplying DC power to the inverter 1, the regenerative energy storage means 6, the DC / DC converter 7 connecting the regenerative energy storage means 6 and the DC input of the inverter 1, and the inverter 1. A voltage detector 8 for detecting a DC input voltage, a current detector 9 for detecting a current flowing between the regenerative energy storage means 6 and the DC / DC converter 7, and a DC based on the detected current of the current detector 9. The flow rate controller 10 controls the flow rate of the / DC converter 7.

The regenerative energy storage device of this embodiment further includes a brake resistor 17 and a brake resistor switch (SLD) 18 which are provided in parallel with the DC capacitor 3.
A switch conduction ratio control unit 19 that controls the conduction ratio of the brake resistance switch 18 according to the detection voltage of the voltage detector 8 is provided.

Next, the operation of the regenerative energy storage device of the fifth embodiment having the above structure will be described. The normal operation of this embodiment is similar to that of the first embodiment shown in FIG. The characteristic of the present embodiment is also in the protection operation, and it operates as follows.

The switch conduction ratio control section 19 uses the inverter 1
When the DC input voltage of the brake resistance is monitored and the appropriate set level R5 determined by the experiment is exceeded, the conduction ratio of the brake resistance switch 18 is increased from zero to increase the brake resistance 1
7 consumes the capacitor current and lowers the DC input voltage.

As a result, in the regenerative energy storage device of the fifth embodiment, even if the regenerative energy is generated in the motor load 2 and the DC input voltage of the inverter 1 rises, the set level R5 is exceeded. If so, the regenerative energy is consumed by the brake resistor 17, the inverter 1 and the DC / DC converter 7 can be protected from an overvoltage, and an excessive regenerative current can be suppressed from flowing into the regenerative energy storage means 6. . In particular, when an electric double layer capacitor is used for the regenerative energy storage means 6, it is effective for protecting the regenerative energy storage means 1 having a fast response.

Next, a regenerative energy storage device according to a sixth embodiment of the present invention will be described with reference to FIGS. 10 and 11. The feature of the sixth embodiment is that the duty ratio controller 10 for the DC / DC converter 7 also monitors the detection voltage of the voltage detector 8 in comparison with the fifth embodiment shown in FIG. If the detected voltage exceeds the set level R6, the switch duty ratio controller 19 increases the brake resistance switch 18 from zero, and the duty ratio controller 10 gate-blocks the DC / DC converter 7. There is a point to do so. Incidentally. Figure 1
In the circuit configuration of 0, components common to the circuit components in the circuit shown in FIG. 8 are designated by the same reference numerals.

As a result, in the regenerative energy storage device of the sixth embodiment, when the DC input voltage of the inverter 1 exceeds the set level R6, the DC / DC converter 7 is gate-blocked and the brake resistance switch 18 is turned on. By increasing the flow rate from zero and causing the regenerative current to be consumed by the brake resistor 17, the DC input voltage is prevented from becoming an overvoltage, the inverter 1 and the DC / DC converter 7 are protected, and the regenerative energy storage means 6 is provided. It is also possible to prevent an excessive regenerative current from flowing into. In particular, when an electric double layer capacitor is used for the regenerative energy storage means 6, it is effective for protecting the regenerative energy storage means 1 having a fast response.

[0062]

As described above, according to the present invention, the protection of the regenerative energy storage device, particularly in the regenerative energy storage device using the electric double layer capacitor as the regenerative energy storage means, the inverter, the DC / DC converter and the regenerative power storage device. The energy storage means can be reliably protected.

In particular, according to the protection method of the regenerative energy storage device of the inventions of claims 1 and 2 and the regenerative energy storage device of the inventions of claims 13 and 14, the regenerative energy becomes large and the DC input voltage of the inverter is set. If it becomes high enough to exceed, the converter's conduction ratio is controlled in such a direction as to increase the charging current regenerated by the regenerative energy storage means through the DC / DC converter, so that overvoltage is prevented from occurring on the DC input side of the inverter. It is possible to suppress and protect the inverter and the DC / DC converter. In particular, when an electric double layer capacitor is used as the regenerative energy storage means, the regenerative energy can be absorbed quickly due to its characteristics, and the DC input voltage can be effectively suppressed.

According to the method for protecting the regenerative energy storage device of the third aspect of the invention and the regenerative energy storage device of the fifteenth aspect of the invention, when the DC input voltage of the inverter reaches the set level, the DC / DC converter is activated. Since all the flow rate is turned on, a large amount of current is supplied to the regenerative energy storage means, the DC input voltage of the inverter is rapidly lowered, and overvoltage can be prevented from occurring on the DC input side of the inverter. The DC / DC converter can be protected. In particular, when an electric double layer capacitor is used as the regenerative energy storage means, the regenerative energy can be absorbed quickly due to its characteristics, so that the overvoltage of the DC input voltage can be effectively prevented.

According to the protection method of the regenerative energy storage device of the invention of claims 4 and 5 and the regenerative energy storage device of the invention of claims 16 and 17, the DC input voltage of the inverter is rapidly increased to the voltage of the regenerative energy storage means. It is possible to reduce the voltage, protect the inverter and the DC / DC converter from overvoltage, and prevent an excessive regenerative current from flowing into the regenerative energy storage means. In particular, when an electric double layer capacitor is used as the regenerative energy storage means, it is effective for protecting the regenerative energy storage means having a fast response.

According to the method of protecting the regenerative energy storage device of the sixth aspect of the invention and the regenerative energy storage device of the eighteenth aspect of the invention, regenerative energy is generated in the motor load and the DC input voltage of the inverter rises. Even if the set level is exceeded, the regenerative energy is consumed by the brake resistance, the inverter and the DC / DC converter can be protected from overvoltage, and an excessive regenerative current is suppressed from flowing into the regenerative energy storage means. You can also do it. In particular, when an electric double layer capacitor is used as the regenerative energy storage means, it is effective for protecting the regenerative energy storage means having a fast response.

According to the protection method of the regenerative energy storage device of the invention of claim 7 and the regenerative energy storage device of the invention of claim 19, when the DC input voltage of the inverter exceeds the set level, the DC / DC converter is gate-blocked. In addition, since the duty ratio of the brake resistance switch is increased from zero to cause the regenerative current to be consumed by the brake resistance, the DC input voltage is prevented from becoming an overvoltage, and the inverter and D
It is also possible to protect the C / DC converter and prevent an excessive regenerative current from flowing into the regenerative energy storage means. In particular, when an electric double layer capacitor is used as the regenerative energy storage means, it is effective for protecting the regenerative energy storage means having a fast response.

According to the regenerative energy storage device protection method of the tenth aspect of the invention and the regenerative energy storage device of the twenty-second aspect of the invention, since a capacitor is provided between the output terminals of the regenerative energy storage means, a DC operating at high frequency is provided. / DC
This capacitor can be buffered between the converter and the charging / discharging operation of the regenerative energy storage means.

[Brief description of drawings]

FIG. 1 is a circuit block diagram of a regenerative energy storage device according to a first embodiment of the present invention.

FIG. 2 is a timing chart of a protection operation of the regenerative energy storage device according to the first embodiment of the present invention.

FIG. 3 is a timing chart of a protection operation of the regenerative energy storage device according to the second embodiment of the present invention.

FIG. 4 is a circuit block diagram of a regenerative energy storage device according to a third embodiment of the present invention.

FIG. 5 is a timing chart of a protection operation of the regenerative energy storage device according to the third embodiment of the present invention.

FIG. 6 is a circuit block diagram of a regenerative energy storage device according to a fourth embodiment of the present invention.

FIG. 7 is a timing chart of a protection operation of the regenerative energy storage device according to the fourth embodiment of the present invention.

FIG. 8 is a circuit block diagram of an energy storage device according to a fifth embodiment of the present invention.

FIG. 9 is a timing chart of a protection operation of the energy storage device according to the fifth embodiment of the present invention.

FIG. 10 is a circuit block diagram of a regenerative energy storage device according to a sixth embodiment of the present invention.

FIG. 11 is a timing chart of a protection operation of the regenerative energy storage device according to the sixth embodiment of the present invention.

FIG. 12 is a circuit diagram of a secondary battery as a regenerative energy storage means in the present invention.

FIG. 13 is a circuit diagram of an electric double layer capacitor as a regenerative energy storage means in the present invention.

FIG. 14 is a circuit diagram in which a capacitor is provided between the output terminals of the regenerative energy storage means in the present invention.

FIG. 15 is a circuit diagram of a chopper type DC / DC converter as a DC / DC converter in the present invention.

[Explanation of symbols]

1 inverter 2 motor load 3 DC capacitor 4 reactor 5 DC source 6 Regenerative energy storage means 7 DC / DC converter 8 voltage detector 9 Current detector 10 Flow rate control unit 11 capacitors 12 power switch 13 Discharge resistance 14 Discharge resistance switch 15 Switch control unit 16 terminal switch 17 Brake resistance 18 Brake resistance switch 19 Switch conduction ratio controller

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Kazuaki Yuki             No. 1 Toshiba-cho, Fuchu-shi, Tokyo Toshiba Corporation             Fuchu Office F-term (reference) 5G003 AA07 BA02 CA11 CC02 DA07                       DA15 FA06 GB03 GB06                 5H115 PA08 PA11 PC02 PC06 PG01                       PG04 PG10 PI11 PI16 PI29                       PO02 PO06 PO17 PU08 PV02                       PV09 QE10 QI03 QI12 SE04                       SE06 TI05 TO13 TR03 TU05

Claims (24)

[Claims] 1. An inverter for converting direct current into alternating current, a motor load driven by the inverter, a direct current capacitor for suppressing instantaneous ripple of a direct current input voltage of the inverter, a direct current source, and regenerative energy storage means. A method of protecting a regenerative energy storage device comprising a DC / DC converter connecting the regenerative energy storage means and a DC input of the inverter, and a duty ratio control means for controlling the duty ratio of the DC / DC converter. Then, the DC input voltage of the inverter is detected, and when the detected voltage exceeds a set level, the duty factor of the DC / DC converter is changed to increase the charging current to the regenerative energy storage means. A method for protecting a regenerative energy storage device characterized. 2. The DC input voltage of the inverter is detected, and when the detected voltage exceeds a set level, the D
The method for protecting a regenerative energy storage device according to claim 1, wherein the conduction ratio of the C / DC converter is increased. 3. The DC / DC converter is a chopper type, and detects a DC input voltage of the inverter, and when the detected voltage exceeds a set level, a charging current for a regenerative energy storage unit of the DC / DC converter. The method for protecting a regenerative energy storage device according to claim 1, wherein all the switching elements on the side of flowing the current are turned on. 4. An inverter for converting direct current into alternating current, a motor load driven by the inverter, a direct current capacitor for suppressing instantaneous ripple of a direct current input voltage of the inverter, a direct current source, and regenerative energy storage means. The DC / DC converter that connects the regenerative energy storage means and the DC input of the inverter, the duty ratio control means that controls the duty ratio of the DC / DC converter, and the output terminal of the DC source are provided. A method of protecting a regenerative energy storage device comprising a power switch and a discharge resistance and a discharge resistance switch provided in parallel with the DC capacitor, wherein the DC input voltage of the inverter is detected, and the detected voltage exceeds a set level. As a result, the DC / DC converter is gate-blocked, the power switch is turned off, and the discharge is performed. Protection method for regenerative energy storage device, characterized in that on the anti switch. 5. An inverter for converting direct current into alternating current, a motor load driven by the inverter, a direct current capacitor for suppressing instantaneous ripple of the inverter direct current input voltage, a direct current source, a regenerative energy storage means, and the regenerative power source. A DC / DC converter connecting the energy storage means and the DC input of the inverter, a duty ratio control means for controlling the duty ratio of the DC / DC converter, and a power switch provided at the output end of the DC source. A discharge resistance and a discharge resistance switch provided in parallel with the DC capacitor,
A method of protecting a regenerative energy storage device comprising a terminal switch provided at an input / output terminal of the regenerative energy storage means, wherein a DC input voltage of the inverter is detected, and the detected voltage exceeds a set level, A method of protecting a regenerative energy storage device, characterized in that the DC / DC converter is gate-blocked, the power switch is turned off, the terminal switch is turned off, and the discharge resistance switch is turned on. 6. An inverter for converting direct current into alternating current, a motor load driven by the inverter, a direct current capacitor for suppressing instantaneous ripple of an inverter direct current input voltage, a direct current source, a regenerative energy storage means, and the regenerative power source. A DC / DC converter that connects the energy storage means and the DC input of the inverter, a brake resistance and a brake resistance switch that are provided in parallel with the DC capacitor, and a switch flow that controls the flow rate of the brake resistance switch. A method of protecting a regenerative energy storage device comprising a rate control means, wherein a DC input voltage of the inverter is detected, and when the detected voltage exceeds a set level, the conduction ratio of the brake resistance switch is set to the DC input. Protection of regenerative energy storage device characterized by controlling in the direction of decreasing voltage Law. 7. An inverter for converting direct current into alternating current, a motor load driven by the inverter, a direct current capacitor for suppressing instantaneous ripple of an inverter direct current input voltage, a direct current source, a regenerative energy storage means, and the regenerative power source. A DC / DC converter connecting the energy storage means and the DC input of the inverter, a duty ratio control means for controlling the duty ratio of the DC / DC converter, a brake resistor provided in parallel with the DC capacitor, and A method for protecting a regenerative energy storage device comprising a brake resistance switch and a switch conduction ratio control means for controlling a conduction ratio of the brake resistance switch, wherein a DC input voltage of the inverter is detected and a detection voltage is set. When the level exceeds the level, the DC input voltage decreases the conduction ratio of the brake resistance switch. Controlling the direction, the protection method of the regenerative energy storage device, which comprises a gate blocking the DC / DC converter. 8. The DC / DC converter is a chopper type converter, wherein the DC / DC converter is a chopper type converter.
7. The method for protecting the regenerative energy storage device according to any of 7. 9. The DC / DC converter is a high frequency isolated converter.
7. The method for protecting the regenerative energy storage device according to any one of to 7. 10. The method for protecting a regenerative energy storage device according to claim 1, wherein a capacitor is provided between the terminals of the regenerative energy storage means. 11. The method for protecting a regenerative energy storage device according to claim 1, wherein the regenerative energy storage means is a secondary battery. 12. The regenerative energy storage means is an electric double layer capacitor.
0. The method for protecting the regenerative energy storage device according to 0. 13. An inverter for converting direct current into alternating current, a motor load driven by the inverter, a direct current capacitor for suppressing instantaneous ripple of a direct current input voltage of the inverter, and a direct current source for supplying direct current power to the inverter. A regenerative energy storage means, a DC / DC converter that connects the regenerative energy storage means and a DC input of the inverter, a voltage detector that detects a DC input voltage of the inverter, and a detection voltage of the voltage detector. Exceeds a set level, the regenerative energy storage means for controlling to change the flow rate of the DC / DC converter in a direction to increase the charging current to the regenerative energy storage means. apparatus. 14. The conduction ratio control means controls to increase the conduction ratio of the DC / DC converter when the detection voltage of the DC input voltage of the inverter exceeds a set level. The regenerative energy storage device according to claim 13. 15. The DC / DC converter is of a chopper type, and the duty ratio control means is configured to detect the DC input voltage of the inverter when the detected voltage exceeds a preset level.
14. The regenerative energy storage device according to claim 13, wherein all of the switching elements on the side for supplying the charging current to the regenerative energy storage means of the / DC converter are turned on. 16. An inverter for converting direct current to alternating current, a motor load driven by the inverter, a direct current capacitor for suppressing instantaneous ripple of direct current input voltage of the inverter, and a direct current source for supplying direct current power to the inverter. A regenerative energy storage means, a DC / DC converter that connects the regenerative energy storage means and the DC input of the inverter, a power switch provided at the output end of the DC source, and a DC capacitor provided in parallel with the DC capacitor. A discharge resistance and a discharge resistance switch, a voltage detector for detecting a DC input voltage of the inverter, and a detection voltage of the voltage detector exceeding a set level, thereby gate-blocking the DC / DC converter,
A regenerative energy storage device comprising: control means for turning off the power switch and turning on the discharge resistance switch. 17. An inverter for converting direct current into alternating current, a motor load driven by the inverter, a direct current capacitor for suppressing instantaneous ripple of an inverter direct current input voltage, and a direct current source for supplying direct current power to the inverter. A regenerative energy storage means, a DC / DC converter that connects the regenerative energy storage means and a DC input of the inverter, a power switch provided at an output end of the DC source, and a DC capacitor provided in parallel. A discharge resistance and a discharge resistance switch, a terminal switch provided at the input / output terminal of the regenerative energy storage means, a voltage detector for detecting a DC input voltage of the inverter, and a detection voltage of the voltage detector having a set level. By exceeding the above, the DC / DC converter is gate-blocked,
A regenerative energy storage device comprising: control means for turning off the power switch, turning off the terminal switch, and turning on the discharge resistance switch. 18. An inverter for converting DC into AC, a motor load driven by the inverter, a DC capacitor for suppressing instantaneous ripple of an inverter DC input voltage, and a DC source for supplying DC power to the inverter. Regenerative energy storage means, a DC / DC converter that connects the regenerative energy storage means and the DC input of the inverter, a brake resistor and a brake resistance switch that are provided in parallel with the DC capacitor, and a DC input voltage of the inverter. And a switch conduction ratio control means for controlling the conduction ratio of the brake resistance switch in a direction in which the DC input voltage decreases in response to the detection voltage of the voltage detector exceeding a set level. And a regenerative energy storage device comprising. 19. An inverter for converting DC into AC, a motor load driven by the inverter, a DC capacitor for suppressing instantaneous ripple of an inverter DC input voltage, and a DC source for supplying DC power to the inverter. Regenerative energy storage means, a DC / DC converter that connects the regenerative energy storage means and the DC input of the inverter, a brake resistor and a brake resistance switch that are provided in parallel with the DC capacitor, and a DC input voltage of the inverter. And a voltage detector that detects a voltage, and controls the conduction ratio of the brake resistance switch in the direction in which the DC input voltage decreases due to the detection voltage of the voltage detector exceeding a set level, and the DC / DC converter A regenerative energy storage device comprising a gate blocking control means. 20. The DC / DC converter is a chopper type converter.
4. The regenerative energy storage device according to any one of 4 and 16 to 19. 21. The DC / DC converter is a high frequency isolated converter.
4. The regenerative energy storage device according to any one of 4 and 16 to 19. 22. A capacitor is provided between the terminals of the regenerative energy storage means.
1. The regenerative energy storage device according to any one of 1. 23. The regenerative energy storage device according to claim 13, wherein the regenerative energy storage means is a secondary battery. 24. The regenerative energy storage means is an electric double layer capacitor.
22. The regenerative energy storage device according to any one of 22.