JPS5911926B2 - constant voltage power supply - Google Patents

Description

[Detailed description of the invention] The present invention relates to improvements in constant voltage power supplies.

Generally, a constant voltage power supply circuit is constructed as shown in FIG.

That is, FIG. 1 shows a constant voltage power supply circuit equipped with means for keeping the output voltage constant, and is equipped with a pulse width control circuit 12 that controls the output pulse from the pulse generation circuit 11.
The switching operation is performed using pulses whose pulse width is controlled by a transformer, which is transmitted to the secondary side by a transformer, rectified by a diode, and passed through a smoothing circuit to obtain a constant output at the load. Note that the part that performs switching operation, the part that includes a transformer, a diode, and a smoothing circuit is referred to as a ringing choke converter 13. However, in the constant voltage power supply device configured in this way, it is not possible to obtain a large current output, and the current output in this device is approximately 15 OA at most, depending on the ratings of the components.

Therefore, in view of the above-mentioned points, the present invention provides a constant voltage power supply device 0 that can obtain a large current output and reduce the ripple included in the DC output voltage.

That is, the present invention is a constant voltage power supply device in which a plurality of inverters including switching elements are connected in parallel, and pulses are applied to each switching element while sequentially changing the phase.

・5 An embodiment of the present invention will be described below with reference to FIGS. 2 and 4. Figure 2 shows the pulse generation circuit 2 similar to Figure 1.
1. A constant voltage power supply device including a pulse width control circuit 22 and a plurality of ringing choke converters 23 connected in parallel. Specifically explained foo and pulse generation circuit 2
1 has a diode 21a and a thyristor 21b connected in series, a resistor 21c) a capacitor 21d, a coil 21e and a thyristor 21f connected in series, and a resistor 21g and a capacitor 21 connected in series. The connected ones are connected in parallel. The pulse generating circuit 21 connected in this way has a three-phase AC 20
0V is applied. From the pulse circuit, Figure 4a
-D, phase-shifted pulses are soft-started 24 only at startup, and are sent to the ringing choke converters 231, 2 through the pulse width control circuit 22.
32, 233, and 234. Specifically, the pulse whose pulse width is controlled by the pulse width control circuit 22 is
The high frequency gate turn-off thyristor GT of the ringing choke converter 23 is connected to the ringing choke converter 23 via the gate circuit 25 respectively.
It is applied to the gate of the switching element 26 made of O.

Note that the pulse width control circuit 22 is controlled by a signal from an error amplifier 28 to maintain a constant voltage. By applying this pulse, each GTO is sequentially turned on. Note that a resistor 23a and a capacitor 23b connected in series are connected in parallel with this GTO 26. In this way, the GTO is operated, and the transformer 23c
and transmits the signal to the secondary side through six shot diodes 23d.
A smoothing circuit is formed by capacitors 23e and 23f and a coil 23g, and an output is provided to a load 27.

In the device constructed in this manner, four-phase clock pulses are sent by the pulse generator 21 to the switching element 26 via the pulse width control circuit 22.

The ripple frequency of the final output is four times the fundamental frequency, or 4.5, as shown in FIG.

Furthermore, an output current of 600A, which is four times that of 150A, can be obtained. As explained above, it is possible to reduce the amount of ripple compared to the conventional filter, thereby making it possible to downsize the filter.

In addition, such a device has the advantage that the ringing chain converter 23 can be selectively selected when the load is light, and the converter can be operated according to the load. Note that the configuration of the above embodiment is not limited to that shown in FIG.
Any configuration shown in the figure may be used.

Note that the number of converters is not limited to four, and for example, about six or eight converters may be provided.

[Brief explanation of the drawing]

Fig. 1 is a block diagram of a conventional constant voltage power supply device, Fig. 2 is a block diagram of an embodiment of the present invention, Fig. 3 is a circuit diagram specifically showing Fig. 2, and Figs. 4 a to d. 5 is a pulse waveform in which a pulse whose pulse width is controlled is applied from a pulse generator to a switching element, and FIG. 5 is a waveform of an output ripple frequency. 21... Pulse generator, 22... Pulse width control circuit, 23... Ringing chain converter, 26... Switching element.

Claims (1)

[Claims] 1. In a constant voltage power supply device comprising a pulse generation circuit, a pulse width control circuit that controls output pulses from the generation circuit, and a plurality of converters having switching elements operated by the control circuit, the plurality of A constant voltage power supply device characterized in that a pulse width control circuit applies a pulse whose phase is temporally changed to each switching element of the converter.