JPH1032937A - Ac-dc converter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an AC-DC converter that is suitable for charging a large capacity battery being mounted to a large-sized battery type vehicle. SOLUTION: In a charging circuit for connecting an AC power supply 1 and a battery 5 via a rectification element being connected in a bridge form, the rectification element is connected via the terminal of the above AC power supply 1 and a choke coil 3 for boosting, a switching element is connected in parallel to each of rectification elements being connected in a bridge form, and at the same time a comparator 15 is provided to turn on either upper or lower switching element with a charge voltage detection signal, a charge current detection signal, and a pulse signal from a triangular wave oscillator 14 as input.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an AC battery suitable for charging a large capacity battery mounted on a large battery powered vehicle.
-It relates to a DC converter.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 7, a rectifying circuit formed by connecting rectifying elements in a bridge and a smoothing circuit are connected to form a primary DC power supply.

[0003]

As described above, conventionally, a rectifying circuit in which rectifying elements are connected in a bridge shape and a smoothing circuit are connected to form a primary DC power supply. Due to the influence, the current waveform on the primary side has a problem that the waveform is distorted as shown in FIG.

[0004]

According to the present invention, there is provided a charging circuit for connecting an AC power supply to a battery via a rectifying element connected in a bridge-like manner, wherein the rectifying element is connected via a terminal of the AC power supply and a boost choke coil. And a switching element connected in parallel to each of the rectifying elements connected in a bridge-like manner, and a charging voltage detection signal, a charging current detection signal, and a pulse signal from a triangular wave oscillator as inputs. According to the present invention, there is provided a configuration including a comparator for turning on an element, and the above-described problem is solved.

[0005]

The principle operation of the present invention will be described. When the switching element SW1 is turned on, as shown in FIGS. 1, 2 and 3, an input power supply (which is originally an AC power supply, A description will be given of a DC power supply for simplicity.) A current flows from VB1 through boosting choke coil L and switching element SW1, and induced energy is accumulated in boosting choke coil L. When the switching element SW1 enters a non-conducting state in a state where the boosted choke coil L stores the induced energy, as shown in FIG. 2, the induced energy stored in the booster choke coil L becomes the input power supply VB1. And the current flows through the rectifying element D1 to charge the battery B. As shown in FIG. 3, the waveform according to the present principle can charge the battery B having a higher voltage than the input power supply VB1 by repeating this operation.

The principle operation of the present invention will be described in the case of an AC power supply as an input power supply. As shown in FIGS. 4 and 5, VB1 is an input power supply and 18 is an input power supply.
Is composed of a rectifier circuit composed of four rectifiers connected in a bridge and a battery B, and the switching element SW is connected only to the upper and lower two rectifiers D2 and D3 of the rectifier circuit 18.
2. When SW3 is individually connected and AC voltage is applied,
Input waveform as shown in FIG.
When the chopper signal is applied alternately to SW2 and SW3, the input voltage waveform applied to the battery B shown in FIG. 5 is obtained.

[0007]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.
FIG. 6 is a circuit diagram of one embodiment of the present invention. 1 is a three-phase AC power supply, 2 is an AC filter, 3 is a choke coil, 4 is a rectifier with a chopping function, 5 is a main power source from a battery, and a three-phase AC power supply 1, an AC filter 2, a choke coil 3, and a chopping coil. The rectifier with function 4 and the battery 5 are connected in series. The rectifier 4 with a chopping function connects three rectifiers D1 to D6 to the bridge at the upper stage and three rectifiers D1 to D6 at the lower stage, and all of these six rectifiers D1 to D6 individually switch the switching elements UP, VP, and W.
P, UN, VN and WN are connected and choke coil 3
Is connected to the three-phase AC power supply 1 via the
Is also connected. Note that resistors R1 and R2 for obtaining a voltage value are connected to a stage preceding the battery 5.

The switching elements UP, VP, WP, UN, VN and WN
A description will be given of the entire contents of the switching control circuit for controlling the switching. The switching control circuit 6 is a three-phase insulating transformer, 7 is an automatic voltage regulator, 8 is a current limit regulator, 9 is a U-phase multiplier, 10 is a W-phase multiplier, and 11 is a U-phase multiplier.
Phase controller, 12 is W-phase controller, 13 is-(U-phase + W-phase)
The control unit 14 includes a triangular wave generating unit, and the comparator 15 includes a comparator. The automatic voltage adjusting unit 7 receives a voltage value obtained by a resistor R2 connected in parallel with the preceding stage of the battery 5.
The current value obtained by the current sensor for the battery 5 is input to the current limit adjusting unit 8. The input of the three-phase AC power supply 1 is applied to the U-phase multiplying means 9 and the W-phase multiplying means 10 via the three-phase insulating transformer 6, and the output from the automatic voltage adjusting means 7 is also applied to each of them. You. A signal obtained by superimposing the U-phase current value of the three-phase AC power supply 1 on the output from the U-phase multiplying means 9 is applied to the U-phase control unit 11, and the W-phase multiplying means 10 is A signal obtained by superimposing the U-phase current value of the three-phase AC power supply 1 on the output from the power supply is applied. The outputs of the U-phase control unit 11 and the W-phase control unit 12 are applied to respective terminals of the comparator 15, and are also applied to the-(U-phase + W-phase) control unit 13, and-(U-phase + W-phase). ) The control unit 13 is applied to the corresponding terminal of the comparator 15. The input side of the comparator 15 includes the U-phase control unit 11 and the W-phase control unit 12
And the output from the-(U-phase + W-phase) control unit 13 and a triangular wave generation circuit 14 corresponding to each input.
Of the switching elements UP and V connected to the choke coil 3 from the comparator 15.
Signals for individually controlling the timing of P, WP, UN, VN and WN are output.

[0009]

As described above, the present invention relates to a charging circuit for connecting an AC power supply to a battery through a rectifying element connected in a bridge-like manner, and to a charging circuit via one terminal of the AC power supply and a boost choke coil. The switching elements are connected in parallel to the individual rectifying elements on either side of the rectifying elements connected in a bridge-like manner, and the charging voltage detection signal, the charging current detection signal, and the output from the triangular wave oscillator. When the switching element SW1A is turned on as a circuit configuration in which a comparator for turning on one of the switching elements with a pulse signal as an input is connected to the switching element, as shown in FIG. A current flows through the switching element SW1, and induced energy is stored in the choke coil 3. It is. In a state where the induced energy is stored in the choke coil 3, the switching element SW
When the battery 1 is turned off, the induced energy stored in the choke coil 3 is added to the voltage of the battery B, as shown in FIG. Since the battery is configured to be charged, the current waveform is almost equal to the voltage waveform in a simple circuit, and a remarkable effect is obtained in that a disturbance caused by a harmonic can be minimized.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a state in which induced energy is stored in a choke coil.

FIG. 2 is a diagram illustrating a state in which induced energy is released to a choke coil.

FIG. 3 shows a charging circuit diagram connected to an AC power supply.

FIG. 4 shows a waveform diagram of the charging circuit diagram of FIG.

FIG. 5 shows a charging circuit diagram according to another embodiment of the present invention.

FIG. 6 shows a waveform diagram in FIG.

FIG. 7 shows a conventional circuit diagram.

FIG. 8 shows a waveform diagram of a conventional circuit.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 AC power supply 2 AC filter 3 Choke coil 4 Rectifier with chopping function 5 Battery 6 Three-phase insulating transformer 7 Automatic voltage adjustment means 8 Current limit adjustment means 9 U-phase multiplication means 10 W-phase multiplication means 11 U-phase control unit 12 W-phase Control unit 13-(U-phase + W-phase) control unit 14 Triangular wave generation circuit 15 Comparator

Claims (1)

[Claims] 1. A charging circuit for connecting an AC power supply and a battery via a rectifying element connected in a bridge-like manner, wherein the charging circuit is connected to a rectifying element via a terminal of the AC power supply and a boost choke coil. A switching element is connected in parallel to each connected rectifier element, and a charging voltage detection signal, a charging current detection signal, and a pulse signal from a triangular wave oscillator are input and a comparator is provided to turn on one of the upper and lower switching elements. AC-DC converter.