JP3186312B2 - Electric vehicle regeneration system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a regeneration system for an electric vehicle that regenerates rotational energy of an electric motor provided in the electric vehicle.

[0002]

2. Description of the Related Art As a regenerative system for an electric vehicle that regenerates rotational energy of an electric motor provided in an electric vehicle, an electric double-layer capacitor having a large charge density is conventionally connected in parallel to a battery, and the battery and the battery are connected during power running. There is known a method in which a motor is driven by a voltage obtained by an electric double-layer capacitor, the rotational energy of the motor is converted into a voltage during regeneration, and the voltage is returned to the battery and the electric double-layer capacitor.

In this case, the electric double-layer capacitor is composed of an organic electrolyte for storing electricity, a high-capacity activated carbon electrode, a separator, etc., has a capacity of about 100 to 470 Farads, and has a rapid charge of 100 amperes or more. What can discharge is used.

[0004]

In such a regenerative system for an electric vehicle, an electric double-layer capacitor is connected in parallel to a battery. Therefore, when an electric motor is driven, an electric double-layer capacitor is required. Since the voltage of the capacitor does not become lower than the voltage of the battery, the electric energy stored in the electric double-layer capacitor cannot be fully utilized, and there is a problem that the effect of extending the cruising distance of the electric vehicle is small.

In view of the above circumstances, the present invention is capable of effectively storing a voltage obtained by a regenerative operation of a motor in a capacitor, and effectively extracting and using electric energy stored in the capacitor. An object of the present invention is to provide a regenerative system for an electric vehicle that can greatly extend the cruising distance of the electric vehicle.

[0006]

In order to achieve the above object, the present invention has a rechargeable battery, which drives a motor by electric energy stored in the battery at the time of power running, and the motor at the time of regeneration. electrical energy but that the regeneration system of an electric vehicle to be recovered through the mechanical energy into electrical energy, obtained by the regenerative operation
Large capacitors used for energy storage,
Check whether the electric vehicle is in regenerative operation or non-regenerative operation
A regenerative operation detecting means for outputting the regenerative operation;
A charging circuit for charging this electric energy obtained by regenerative operation of the motor when detecting an operation by supplying to the capacitor, the regenerative operation detecting means non-regenerative operation
Until preset when the condition is satisfied when it is detected, with discharging the capacitor, and a boosting circuit which boosts the voltage obtained by the discharge operation for driving the charge or the electric motor of the battery, It is characterized by having.

[0007]

In the above configuration, during the regenerative operation, the electric energy obtained by regenerating the electric motor by the charging circuit is obtained.
There it is charged is supplied to the large-capacity capacitor, non
During the regenerative operation , the capacitor is discharged until the condition set in advance by the booster circuit is satisfied, and the voltage obtained by this discharging operation is boosted to charge the battery or drive the electric motor. It is.

[0008]

FIG. 1 is a block diagram showing an electric motor drive system to which an embodiment of an electric vehicle regenerative system according to the present invention is applied.

The motor drive system shown in FIG. 1 includes a power supply circuit 2, a control circuit 3, a booster circuit 4, and a power circuit 5
And a charging circuit 6 and an electric double-layer capacitor 7, depending on the opening degree of the accelerator pedal 8, during power running operation,
It is determined whether the vehicle is in the non-powered operation.
And the voltage obtained by the voltage of the electric double-layer capacitor 7 is converted into an AC voltage by the power circuit 5 to drive the motor 9, and at the time of regenerative operation, the rotational energy of the motor 9 is recovered and the voltage is recovered. Is stored in the electric double layer capacitor 7 by the charging circuit 6.

The power supply circuit 2 includes a large-capacity battery 10 connected in series. The power supply circuit 2 generates a voltage having a preset value and supplies the generated voltage to the power circuit 5 via the booster circuit 4.

The control circuit 3 has a variable resistor and determines the amount of depression of the accelerator pedal 8 by an electric signal (opening detection signal).
And a regenerative operation instruction signal (“1” signal) or a non-regenerative operation instruction signal (“0” signal) based on the opening detection signal output from the accelerator opening sensor 11. A regenerative operation detection / comparison circuit 12 for generating a non-regenerative operation instruction signal when the amount of depression of the accelerator pedal 8 is greater than a preset amount (when the accelerator pedal 8 is depressed greatly). Is supplied to the booster circuit 4, and when the depression amount of the accelerator pedal 8 is equal to or less than a preset amount (when the accelerator pedal 8 is returned), this is detected to generate a regeneration operation instruction signal, This is supplied to the charging circuit 6.

As shown in FIG. 2, the booster circuit 4 has a voltage detection circuit 13 for taking in the voltage of the battery 10 and generating a voltage detection signal, and a voltage detection signal output from the voltage detection circuit 13 is preset. When the value is lower than the value (set value), the comparator 14 generates a discharge permission signal (“1” signal), and otherwise generates a discharge inhibition signal (“0” signal) and the control circuit 3 outputs the signal. An inverter circuit 15 that inverts the non-regenerative operation instruction signal (“0” signal) to generate a discharge instruction signal (“1” signal); a discharge instruction signal output from the inverter circuit 15; Circuit 1 that generates a drive instruction signal (“1” signal) when a discharge permission signal is output from
6 is provided.

The boosting circuit 4 further includes a square wave generating circuit 17 for generating a square wave signal when the driving instruction signal is output from the AND gate circuit 16, and a square wave signal output from the square wave generating circuit 17. When the driving signal is output, a driving circuit 18 generates an on / off driving signal, when the driving signal is output from the driving circuit 18, a semiconductor switch 19 that is turned on / off, and the semiconductor switch 19 is turned on. The electric double layer capacitor 7 is discharged, magnetic energy is stored, and the semiconductor switch 1 is turned off.
9 when the back electromotive voltage is generated by the coil 20 while preventing the voltage of the battery 10 from flowing to the electric double layer capacitor 7 while the coil 20 generating the back electromotive voltage by the stored magnetic energy. , And a diode 21 for passing this.

The booster circuit 4 includes a battery 10
Is constantly checked whether the voltage value is higher than a preset voltage value (set voltage value), and when the voltage value of the battery 10 is lower than the set voltage value, the non-regenerative operation instruction signal is sent from the control circuit 3. Is output, the electric double-layer capacitor 7 is discharged, and the voltage obtained by this discharging operation is boosted to supply a voltage to the power circuit 5 and the battery 10, and the voltage value of the battery 10 becomes the set voltage value. When the above is reached, the power circuit 5 and the battery 1
The voltage supply operation for 0 is stopped.

The power circuit 5 has a voltage stabilizing capacitor 22 for receiving and stabilizing the voltage output from the battery 10 and the booster circuit 4 of the power circuit 2, and is stabilized by the capacitor 22. A switching circuit 23 for converting the applied voltage into an alternating current of a plurality of phases to perform a power running operation of the motor 9 and a regenerative operation, and when a drive signal is output from a drive control circuit (not shown). , A voltage stabilized by the capacitor 22 is taken in, a plurality of phases of alternating current are generated, and the motor 9 is rotated. When a regenerative signal is output from the drive control circuit, the rotational energy of the motor 9 is converted into electric energy. And supplies it to the battery 10 and the charging circuit 6 of the power supply circuit 2.

As shown in FIG. 3, the charging circuit 6 compares the voltage value of the electric double layer capacitor 7 with the voltage value of the battery 10, and calculates the difference between the voltage value of the battery 10 and the voltage value of the electric double layer capacitor 7. Is greater than a preset value (set voltage difference), an intermittent charge instruction signal (“1” signal)
In other cases, the comparison circuit 24 generates a continuous charge instruction signal (“0” signal). When the comparison circuit 24 outputs a continuous charge instruction signal (“0” signal), Charge waveform signal (continuous "1" signal)
, A square wave generating circuit 26 for generating a square wave signal of a preset cycle, and an output from the square wave generating circuit 26 when the intermittent charging instruction signal is output from the comparing circuit 24. And an AND gate circuit 27 for passing a square wave signal to be transmitted.

Further, the charging circuit 6 includes the inverter circuit 2
5 outputs the continuous charging waveform signal when the continuous charging waveform signal is output, and outputs the AND gate circuit 2 when the continuous charging waveform signal is not output.
When the regenerative operation instruction signal is output from the control circuit 3 and the continuous charging waveform signal is output from the OR gate circuit 28, the gate-on signal is continuously output. If a square-wave signal is output from the OR gate circuit 28 and a gate-on signal is intermittently generated, the drive circuit 29 generates a gate-on signal intermittently. While preventing the voltage of the semiconductor switch 30 that passes the voltage output from the power circuit 5 and the voltage of the electric double-layer capacitor 7 from returning to the power circuit 5,
A diode 31 that allows a voltage output from the semiconductor switch 30 to pass therethrough.

When the regenerative operation instruction signal is output from the control circuit 3, if the difference between the voltage value of the battery 10 and the voltage value of the electric double layer capacitor 7 is larger than the set voltage difference, the charging circuit 6 The voltage obtained by the regenerative operation of the circuit 5 is taken in and supplied to the electric double layer capacitor 7 to charge it while the voltage is intermittent, and the voltage of the battery 10 and the voltage of the electric double layer capacitor 7 are also charged. Is smaller than the set voltage difference,
The voltage obtained by the regenerative operation of the power circuit 5 is taken in, and this voltage is continuously supplied to the electric double layer capacitor 7 to charge it.

The electric double-layer capacitor 7 is composed of an organic electrolyte for storing electricity, a high-capacity activated carbon electrode, a separator, etc., thereby having a capacity of about 100 to 470 Farads and capable of rapid charging and discharging of 100 amps or more. It has become.

The battery is charged by the voltage output from the charging circuit 6 and discharged by the boosting circuit 4.

Next, the regenerative operation and the non-regenerative operation of this embodiment will be sequentially described with reference to the waveform diagrams shown in FIGS.

<< Regeneration Operation >> First, a square wave signal is continuously generated by the square wave generation circuit 26 of the charging circuit 6 as shown in FIG.

In parallel with this operation, the voltage value of the electric double-layer capacitor 7 and the voltage value of the battery 10 are constantly compared by the comparison circuit 24 of the charging circuit 6, and FIG.
When the difference between the voltage value of the battery 10 and the voltage value of the electric double layer capacitor 7 is larger than a preset value (set voltage difference) as shown in FIG. 4A, an intermittent charge instruction is issued as shown in FIG. A signal is generated, and a square wave signal is output from the AND gate circuit 27 as shown in FIG.
As shown in (f), this square wave signal is supplied to the OR gate circuit 28.
And is supplied to the drive circuit 29.

In this state, the accelerator pedal 8 that has been depressed is returned, and the output voltage of the accelerator opening sensor 11 increases. When the output voltage exceeds a preset value, this is detected by the regenerative operation detection comparison circuit 12. FIG. 4
As shown in (h), a regenerative operation instruction signal is generated and supplied to the drive circuit 29 of the charging circuit 6.

As a result, the driving circuit 29 shown in FIG.
As shown in (g), an intermittent gate-on signal is generated, the semiconductor switch 30 is turned on / off intermittently, and the voltage recovered by the regenerative operation of the power circuit 5 is switched, as shown in FIG. This passes through the diode 31 and the voltage is supplied to the electric double layer capacitor 7, which is charged.

In this case, since the voltage output from the charging circuit 6 is intermittent, the value of the current output from the charging circuit 6 is limited to a predetermined value or less. The destruction of the electric double-layer capacitor 7 due to the excessive charging is prevented.

At this time, the battery 10 of the power supply circuit 2 is slightly charged by the voltage output from the power circuit 5.

Thereafter, the charging of the electric double layer capacitor 7 proceeds, and the difference between the voltage value of the electric double layer capacitor 7 and the voltage value of the battery 10 becomes equal to or less than a preset value. When this is detected by the circuit 24 and the generation of the intermittent charge instruction signal is stopped, and the generation of the continuous charge instruction signal is started, a continuous charge waveform signal is generated by the inverter circuit 25, which is driven through the OR gate. The signal is supplied to a circuit 29.

As a result, a continuous gate-on signal is generated by the drive circuit 29, and the semiconductor switch 30 is continuously turned on. As a result, the voltage recovered by the regenerative operation of the power circuit 5 is brought into a continuous passing state (through state), which is supplied to the electric double layer capacitor 7 via the diode 31, and this electric double layer capacitor 7 is continuously turned on. Charged.

In this case, since the voltage of the electric double layer capacitor 7 has risen to some extent, even if the voltage output from the charging circuit 6 is intermittent,
Will not be destroyed.

Thereafter, if the voltage value of the electric double layer capacitor 7 becomes higher than the voltage value obtained by the regenerative operation of the power circuit 5, the diode 31 is reverse-biased and the electric double layer capacitor 7 is charged. At the same time, the current is prevented from flowing back from the electric double layer capacitor 7 to the power circuit 5.

<< Non-regenerative operation >> Further, the voltage of the battery 10 of the power supply circuit 2 is taken in by the voltage detection circuit 13 of the booster circuit 4, and a voltage detection signal indicating the value of this voltage is obtained as shown in FIG. Generated and the comparison circuit 14
It is determined whether or not the value of the voltage detection signal is equal to or greater than a preset value (set voltage value).
When the voltage of the battery 10 is high and the voltage detection signal is equal to or higher than the set voltage value as shown in FIG.
As shown in (d), a discharge permission signal is generated and supplied to the AND gate circuit 16.

In this state, the accelerator pedal 8 is depressed and the electric motor 9 enters a power running state. In response to this, the value of the opening detection signal output from the accelerator opening sensor 11 increases and this is set in advance. 5 (e.g., at time t1), this is detected by the regenerative operation detection / comparison circuit 12 to generate a non-regenerative operation instruction signal as shown in FIG. 5 and is inverted by the inverter circuit 15 as shown in FIG. 5E, and supplied to the AND gate circuit 16 as a discharge instruction signal.

As a result, the drive instruction signal is generated by the AND gate circuit 16 as shown in FIG.
A square wave signal is output from the square wave generation circuit 17 as shown in FIG.
A drive signal is output from 8 and the semiconductor switch 19 is turned on / off.

Thus, when the semiconductor switch 19 is turned on, the diode 21 prevents the current from flowing from the battery 10 to the semiconductor switch 19, and the electric current flows through the coil 20 as shown in FIG. 2
The electric charge of the multilayer capacitor 7 is discharged, and the discharge stores magnetic energy in the coil 20.

When the semiconductor switch 19 is turned off, a back electromotive voltage is generated by the magnetic energy stored in the coil 20, and this is supplied to the battery 10 via the diode 21. As shown in FIG. 5, the discharge current of the battery 10 is reduced, and the voltage is supplied to the power circuit 5 to be used as a power source for the power running operation.

Thereafter, the switching operation of the semiconductor switch 19 described above is repeated, and the voltage of the electric double layer capacitor 7 is boosted by the coil 20 and the diode 21 so that the discharge current of the battery 10 is reduced. The electric motor 9 is driven by converting the electric current into a phase alternating current.

In this case, if the time from time t1 to time t2 is the powering operation period of the electric motor 9, the voltage generated by the booster circuit 4 is consumed by the power circuit 5, so that the voltage of the battery 10 does not increase. Then, a current flows in the discharge direction.

Thereafter, when the electric motor 9 enters the coasting operation state (for example, at time t2), the voltage generated by the booster circuit 4 is no longer consumed by the power circuit 5, and charging of the battery 10 is started. Voltage gradually rises.

When the voltage of the battery 10 rises to a preset value, the comparison circuit 14 monitoring the voltage detection signal output from the voltage detection circuit 13
As a result, a discharge prohibition signal is output as shown in FIG.

As a result, the drive instruction signal is no longer output from the AND gate circuit 16 and the semiconductor switch 1
9 is stopped, and the charging operation of the battery 10 is stopped.

At this time, the electric double-layer capacitor 7
Is lower than the value of the voltage input to the charging circuit 6, but since the semiconductor switch 19 of the charging circuit 6 is in the off state, the current from the charging circuit 6 to the electric double-layer capacitor 7 side. Does not flow.

As described above, in this embodiment, it is determined whether the vehicle is in the power running operation or the non-power running operation in accordance with the opening degree of the accelerator pedal 8, and in the power running operation, the voltage and electric power obtained by the power supply circuit 2 are determined. The voltage obtained by the voltage of the multilayer capacitor 7 is converted into an AC voltage by the power circuit 5 to drive the motor 9, and at the time of regenerative operation, the rotational energy of the motor 9 is recovered to generate a voltage, which is then charged to a charging circuit. 6, the voltage obtained by the regenerative operation of the electric motor 9 is stored in the electric double-layer capacitor 7.
The electric energy stored in the electric double-layer capacitor 7 can be effectively stored in the electric double-layer capacitor 7, and the electric energy stored in the electric double-layer capacitor 7 can be effectively extracted and used, thereby greatly extending the cruising distance of the electric vehicle. Can be.

Further, in the above-described embodiment, the electric double-layer capacitor 7 is used as a capacitor for storing the electric energy obtained by the regenerative operation. Any type of capacitor may be used as long as it is possible.

In the above-described embodiment, the voltage of the electric double layer capacitor 7 is boosted by using the inductance type booster circuit 4 using the coil 20, the semiconductor switch 19, and the diode 21.
The electric double-layer capacitor 7 is formed by using another type of booster circuit, for example, a diode pump type booster circuit constituted by a capacitor and a semiconductor switch, a diode, or the like.
May be increased.

[0046]

As described above, according to the present invention, the electric energy obtained by the regenerative operation of the electric motor can be effectively stored in the capacitor, and the electric energy stored in the capacitor can be effectively stored. The electric vehicle can be used for a long time, and the range of the electric vehicle can be greatly extended.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating an example of a motor drive system to which an embodiment of an electric vehicle regeneration system according to the present invention is applied.

FIG. 2 is a block diagram showing a detailed circuit configuration example of the booster circuit shown in FIG.

FIG. 3 is a block diagram showing a detailed circuit configuration example of the charging circuit shown in FIG. 1;

FIG. 4 is a waveform diagram showing an example of a regenerative operation of the electric motor drive system shown in FIG.

5 is a waveform chart showing an example of a non-regenerative operation of the electric motor drive system shown in FIG.

[Explanation of symbols]

 2 Power supply circuit 3 Control circuit 4 Boost circuit 5 Power circuit 6 Charging circuit 7 Electric double layer capacitor 8 Accelerator pedal 9 Motor 10 Battery 11 Accelerator opening sensor 12 Regenerative operation detection comparison circuit 19 Semiconductor switch 20 Coil 21 Diode

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B60L 11/18 B60L 7/16 H01G 9/155 H02J 1/00 306

Claims (1)

(57) [Claims] Have 1. A charging freely battery, at the time of power running, the drives the electric motor by the electric energy stored in the battery, at the time of regeneration, the electric motor in the regeneration system of an electric vehicle to be recovered through the electrical energy mechanical energy A large capacitor used to store the electric energy obtained by regenerative operation and whether the electric vehicle is in regenerative operation or non-regenerative operation
A regenerative operation detecting means for output, the charging circuit regenerative operation detecting means for charging this electric energy obtained by regenerative operation of the motor when it detects the regenerative operation is supplied to the capacitor, the regenerative When the operation detecting means detects the non-regenerative operation , the capacitor is discharged until a preset condition is satisfied, and the voltage obtained by the discharging operation is boosted to charge the battery or charge the electric motor. A regenerative method for an electric vehicle, comprising: a booster circuit for driving;