JPH10254558A - Power unit and power system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate the need for a large type as a breaker even if the number of connected power units increases and to evade a momentary stop due to a large rush current of other equipment connected to an AC power source by controlling the operation timing of a switch means which supplies and cuts off AC electric power to a power circuit. SOLUTION: When a power switch is turned on, a 1st power unit 101 has the zero-cross input part ZIN of its zero-cross output circuit 18 supplied with AC power through a power line. Then, when the output waveform of the AC power crosses zero, the zero-cross output circuit 18 sends a zero-cross output from its zero-cross output part ZOUT to the zero-cross input part ZIN of a 2nd power unit 102 and also sends this zero-cross output to a switch circuit 16. Consequently, a bidirectional thyristor 20 of the switch circuit 16 turns on and its AC power source output is supplied to the power circuit 14. Consequently, the power circuit 14 rises from the zero of the output waveform of the AC power.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power supply device provided with a power supply circuit for converting an AC power supply to a DC power supply and supplying it to a load, and a power supply system using the same.

[0002]

2. Description of the Related Art Referring to FIG. 11, a plurality of power supply devices 101, 102, 103,... Are connected in parallel between power supply lines of an AC power supply 2 via a breaker 41 and a power supply switch 61. Power supply units 101, 102, 1
.., A load (not shown) is connected, and another device 104 is also connected between the power supply lines via a breaker 42 and a power switch 42. Each of these power supply devices 101, 102, 103,... Has a full-wave rectifier circuit 10 for full-wave rectification of an AC power supply and a smoothing capacitor 12 for smoothing the output of the full-wave rectifier circuit 10.

[0003]

Power supplies 101, 102, 103,... Having a configuration as shown in FIG. 11 are connected in parallel between the power supply lines of the AC power supply 2 so that the output waveform of the AC power supply 2 becomes high. When the power switch 41 is turned on at time t0 in FIG. 12A, for example, the breaker 41 is not charged until the smoothing capacitor 12 of each of the power supply devices 101, 102, 103,. A large inrush current as shown in FIG. Such an inrush current becomes very large as the number of power supply devices increases, and thus there is a problem that a large breaker 41 is required. Further, in the other devices 104 connected to the AC power supply 2, there is also a problem that such an extremely large rush current may cause inconvenience such as an instantaneous stop.

[0004]

According to the first aspect of the present invention, there is provided a power supply apparatus for converting an AC power supply into a DC power supply and supplying the DC power to a load, and a power supply circuit inserted into an input side of the power supply circuit and connected to the power supply circuit. The above-mentioned object is attained by a configuration having switch means for performing an operation of shutting off the supply of AC power and control means for controlling the operation timing of the switch means.

In the power supply apparatus according to claim 2, the control means outputs a predetermined zero-cross output when the AC output waveform crosses zero.
And an input unit to which the output waveform is given, and an output unit to output the zero-cross output, and a zero-cross output unit that outputs a zero-cross output to the switch unit to operate the switch unit. The above problem is solved by the configuration.

According to a third aspect of the present invention, a plurality of the power supply units according to the first or second aspect are connected in parallel to an AC power supply, and an input of a zero-cross output means of an arbitrary power supply unit. Unit is connected to the power supply line of the AC power supply, and the output units of the zero-cross output means of each power supply device including the arbitrary power supply unit are individually connected to the input units of the respective zero-cross output means. The above-described problem is solved as a characteristic power supply system.

According to a fourth aspect of the present invention, the control unit is a delay unit for delaying the operation timing of the switch unit. Has been resolved.

In a power supply system according to a fifth aspect of the present invention, a plurality of the power supply units according to the fourth aspect are connected in parallel to an AC power supply, and each of the power supply units is switched by a delay means of each of the power supply units. The above-described problem is solved as a power supply system characterized in that the means operates at different operation timings.

[0009]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIGS. 1 to 4 relate to a power supply device and a power supply system using the same according to an embodiment of the present invention.
1 is a circuit diagram showing a power supply system using a plurality of power supply devices according to an embodiment of the present invention, and FIG. 2 is an internal circuit diagram of the power supply device shown in FIG.

In a power supply system using a plurality of power supply devices according to the present embodiment, as shown in FIG.
, A plurality of power supplies 101, 102, 102 between power supply lines 81, 82 via a breaker 4 and a power switch 6.
Are connected in parallel. These power supply devices 10
Each of AC input units IN1 and IN2 connected between the power supply lines 81 and 82 of the AC power supply 2, and DC output units OUT1 and OUT2 connected to the load, as shown in FIG. , A zero-cross input section ZIN and a zero-cross output section ZOUT, and a full-wave rectifier circuit 10 for converting AC into DC and supplying the DC to a load.
And a power supply circuit 14 having, for example, a switching power supply configuration having a smoothing capacitor 12, and a switch circuit 16 as a switch means for switching on or off to switch off the supply of the AC power supply 2 to the power supply circuit 14.
And a zero-cross output circuit 18 as control means for controlling the operation timing of the switch circuit 16. Then, the switch circuit 16 is connected to the AC input sections IN1, I2
While being inserted between N2 and the power supply circuit 14,
A bidirectional thyristor 20 having an input / output unit connected to a power supply line 81 is provided therein. The bidirectional thyristor 20 is adapted to conduct in response to a zero-cross output from the zero-cross output circuit 18 to its gate. . The zero-cross output circuit 18 outputs a zero-cross output to the zero-cross output part ZOUT and the switch circuit 16 when the AC output waveform applied to the zero-cross input part ZIN crosses zero, respectively, as shown in FIG. In the power supply device, the zero-cross input portion ZIN of the first power supply device 101 is connected to one power supply line 81. The zero cross output ZOUT of the first power supply 101 is connected to the zero cross input ZIN of the second power supply 102. Second power supply 102
Is connected to the zero-cross input ZIN of the third power supply device 103. Thus, each of the power supply devices 101, 102, 103,.
Are connected to the AC power supply 2 in parallel,
First power supply 101 selected as an arbitrary power supply
Of the zero-cross output circuit 18 is connected to one power line 81 of the AC power supply 2, and each of the power devices 101, including the first power device 101,
, 102, 103,... Have their zero-cross output sections ZOUT individually connected to the zero-cross input sections ZIN of the power supplies 101, 102, 103,.

The operation will be described with reference to FIGS.

(First power supply device 101) Power switch 6
Is turned on at time t0, the first power supply device 101 outputs the zero-cross output circuit 1 as shown in FIG.
The AC power supply 2 is supplied to the zero-cross input section ZIN 8 through a power supply line 81. Then, when the output waveform of the AC power supply 2 zero-crosses at time t1, the zero-crossing output circuit 18 applies the zero-crossing from the zero-crossing output part ZOUT to the zero-crossing input part ZIN of the second power supply device 102 as shown in FIG. The output is output and the zero-cross output is output to the switch circuit 16. As a result, the bidirectional thyristor 20 of the switch circuit 16 conducts, and the output of the AC power supply 2 is supplied to the power supply circuit 14. As a result, the power supply circuit 14 rises from zero in the output waveform of the AC power supply 2.

(Second power supply device 102) In the second power supply device 102, at time t1, the zero cross output from the zero cross output portion ZOUT of the first power supply device 101 is supplied to the zero cross input portion ZIN. Since the output zero-crosses at time t2, the zero-crossing output circuit 18 outputs the signal from the zero-crossing output ZOUT to the zero-crossing input ZIN of the third power supply 103 as shown in FIG.
And outputs the zero-cross output to the switch circuit 16. As a result, the bidirectional thyristor 20 of the switch circuit 16 conducts, and the output of the AC power supply 2 is supplied to the power supply circuit 14. As a result, the power supply circuit 14 rises from zero in the output waveform of the AC power supply 2.

(Third power supply device 103) In the third power supply device 103, at time t2, a zero cross from the zero cross output portion ZOUT of the second power supply device 102 is supplied to the zero cross input portion ZIN. Crosses zero at time t3, the zero-cross output circuit 1
8 outputs a zero-cross output as shown in FIG. 3D from the zero-cross output part ZOUT to a zero-cross input part ZIN of the next power supply device 103 (not shown), and outputs the zero-cross output to the switch circuit 16. .
Thereby, the bidirectional thyristor 20 of the switch circuit 16
Is conducted, and the output of the AC power supply 2 is supplied to the power supply circuit 14. As a result, the power supply circuit 14 rises from zero in the output waveform of the AC power supply 2.

As described above, in the system using each of the power supply devices 101, 102, 103,... In the present embodiment, the output that has been full-wave rectified by the full-wave rectification circuit 10 from each power supply circuit 14. When charged by the smoothing capacitor 12, the AC power supply 2 shown in FIG.
The full-wave rectified output rises from zero, so that the inrush current in this charging is small as shown in FIG. 4 (b), and since these inrush currents occur differently in time, the conventional power supply Apparatus 101, 102, 1
There is no problem that a large inrush current flows to the breaker 4 when the devices 03,... Rise at the same time, so that a large breaker 4 is required, and other devices are momentarily stopped.

In the above-described embodiment, the switch circuit 16 is located on the front side of the power supply circuit 14.
The switch circuit 16 may be arranged between the full-wave rectifier circuit 10 and the smoothing capacitor 12 as shown by.

In the above-described embodiment, the switch circuit 16 is constituted by the bidirectional thyristor 20, but is not limited to this, and a relay or other switch element may be used.

In the above-described embodiment, the switch-on and switch-off operations of the switch circuit 16 are performed by the zero-cross output from the zero-cross output circuit 18. However, as shown in FIG. It may be done. That is, each of the power supply devices 101, 102, 10
Are provided with delay circuits 22, and the timings of the switch-on and switch-off operations of the switch circuit 16 by the respective delay circuits 22 are made different, so that the inrush currents are simultaneously applied to the respective power supply devices 101, 102, 103,. May be prevented from flowing. In this case, the delay circuit 22 is arranged before the switch circuit 16, but the delay circuit 22 and the switch circuit 16 are arranged between the full-wave rectifier circuit 10 and the smoothing capacitor 12, as shown in FIG. No problem. The delay circuit 22 may be configured such that a delay time can be set by changing the resistance value of the variable resistor using a variable resistor by, for example, charging and discharging a capacitor and a resistor.
The oscillation frequency of this oscillation circuit can be varied with a variable resistor,
The delay time may be set by switching a switch, or the delay time may be set by a commercially available timer.

As described above, each power supply 10
, 1, 102, 103,..., The first delay time in the delay circuit 22 of the first power supply 101 is 1
0 ms, the second delay time in the delay circuit 22 in the second power supply device 102 is 20 ms, and the third delay time in the delay circuit 22 in the third power supply device 103 is 30
ms, when the AC power supply 2 turns on the power switch 6 at time t0 as shown in FIG.
Since the inrush current flowing through each of the breakers 01, 102, 103,... Is different, the inrush current flowing through the breaker 4 is small and does not flow at the same time as shown in FIG.

The power supply units 101, 102, 103,... In the above-described embodiment are controlled by the power supply units in order to control the power supply in any sequence. 101, 102,
9, a timer circuit 26 and a timer switch 28 which is turned on / off by the output of the timer circuit 26 are provided on the output side of the power supply circuit 14, for example, as shown in FIG. , The timer switch 28 can be turned off by the output from the timer circuit 26 at the arrival of the timer set time, so that the load 24 can be started in accordance with the sequence and the power supplies 101, 102, and 10 can be activated.
.. Are activated at the same time, it is possible to prevent a large inrush current from flowing through the breaker 4. The timer circuit 26 includes, for example, a power supply circuit 14 as shown in FIG.
, A series circuit inserted in parallel between the resistor R1 and the variable resistor VR, a capacitor C1 connected in parallel to the variable resistor VR, a transistor TR, and a relay coil RL to form a timer circuit 26. A timer switch 28 is constituted by a relay contact SW, and the charging speed of the capacitor C1 is adjusted by a variable resistor VR to obtain a timer set time.
When the voltage between both ends of the capacitor C1 reaches a predetermined value, that is, when the timer set time has come, the transistor TR is turned on to energize the relay coil RL to turn on the relay contact SW serving as the timer switch 28.

[0022]

As described above, according to the present invention, the following effects can be obtained.

According to the first aspect of the present invention, a power supply circuit for converting an AC power supply to a DC power supply and supplying the load to a load, and an operation for cutting off the supply of the AC power supply to the power supply circuit inserted into the input side thereof. Since the power supply device has a switch means for performing the operation and a control means for controlling the operation timing of the switch means, in a power supply system using a plurality of the power supply means, the smoothing capacitor in the power supply circuit in each power supply device is charged. It is possible to prevent excessive inrush current from flowing to the breaker connected to the power supply line of the power supply source.As a result, even if the number of connected power supply units increases, a large breaker is required. In addition, other devices connected to the AC power supply of each of these power supply devices are prevented from causing instantaneous power failure or the like due to a large inrush current as in the related art.

According to the second aspect of the present invention, the control means outputs a predetermined zero-cross output when the AC output waveform crosses zero, and the input section to which the output waveform is provided; An output section for outputting a zero-cross output, and a zero-cross output means for outputting a zero-cross output to the switch means to operate the switch means, wherein the power supply device according to claim 1, Since the respective power supply devices can be started sequentially and reliably every half cycle of the output waveform of the AC power supply, it is possible to prevent the rush current from flowing to the breaker all at once.

According to a third aspect of the present invention, a plurality of the power supply units according to the first or second aspect are connected in parallel to an AC power supply, and the input section of the zero-cross output means of any power supply unit is connected to the AC power supply. The power supply is connected to a power supply line of the power supply, and the output of the zero cross output means of each power supply including the arbitrary power supply is individually connected to the input of each zero cross output means. Since this is a power supply system, an excessive rush current can be prevented from flowing to the breaker connected to the power supply line of the power supply source.As a result, even if the number of connected power supply units increases, a large breaker can be used. It is no longer necessary, and other devices connected to the AC power supply of each of these power supply units may experience momentary power failure due to a large inrush current as before. DOO is a system to be avoided.

According to a fourth aspect of the present invention, the control unit is a delay unit for delaying the operation timing of the switch unit. Can be started arbitrarily and at a certain timing, so that the rush current described above can be prevented from flowing all at once into the breaker, and the start timing can be changed, so that it is convenient to start the load according to the sequence.

According to a fifth aspect of the present invention, a plurality of the power supply units according to the fourth aspect are connected in parallel to an AC power supply, and each of the power supply units has a different switching unit depending on the delay unit. Since the power supply system is characterized by operating at the operation timing, it is possible to prevent the inrush current from flowing to the breaker at the same time by being able to start each power supply device arbitrarily and at a certain timing, and Since the start timing can be changed, this is a convenient system for starting loads according to a sequence.

[Brief description of the drawings]

FIG. 1 is a circuit diagram of a power supply system using a power supply device according to an embodiment of the present invention.

FIG. 2 is an internal circuit diagram of the power supply device shown in FIG.

FIG. 3 is a timing chart for explaining the operation of the zero-cross output circuit in FIG. 2;

FIG. 4 is a waveform diagram showing an output waveform of an AC power supply and a waveform of an AC current.

FIG. 5 is a circuit diagram of a power supply device according to another embodiment of the present invention.

FIG. 6 is a circuit diagram of a power supply device according to still another embodiment of the present invention.

FIG. 7 is a circuit diagram of a power supply device according to still another embodiment of the present invention.

8 is a timing chart for explaining the operation of the power supply device of FIG. 7;

FIG. 9 is a circuit diagram of a power supply device according to still another embodiment of the present invention.

FIG. 10 is a specific circuit diagram of FIG. 9;

FIG. 11 is a circuit diagram of a power supply system using a conventional power supply device.

FIG. 12 is a timing chart for explaining the operation of FIG. 11;

[Explanation of symbols]

 2 AC power supply 4 Breaker 6 Power switch 81, 82 Power line 101, 102, 103 Power supply 14 Power circuit 16 Switch circuit 18 Zero cross output circuit 20 Bidirectional thyristor IN1, IN2 AC input section OUT1, OUT2 DC output section ZIN Zero cross input section ZOUT Zero cross output section

Claims (5)

[Claims] 1. A power supply circuit for converting an AC power supply into a DC power supply and supplying the load to a load, and a switch inserted into an input side of the power supply circuit for interrupting the supply of the AC power to the power supply circuit.
A power supply unit having control means for controlling operation timing of the switch means. 2. An input unit to which a predetermined zero-cross output is output when an AC output waveform crosses zero, and an output unit to which the output waveform is given, and an output unit that outputs the zero-cross output. And having
2. The power supply device according to claim 1, wherein the power supply unit is a zero-cross output unit that outputs a zero-cross output to the switch unit to operate the switch unit. 3. A plurality of power supplies according to claim 1 or 2 are connected in parallel to an AC power supply, and an input section of a zero-cross output means of any power supply is connected to a power supply line of the AC power supply. A power supply system, wherein the output units of the zero-cross output means of each power supply device including the arbitrary power supply device are individually connected to the input units of the respective zero-cross output means. 4. The power supply device according to claim 1, wherein said control means is a delay means for delaying an operation timing of said switch means. 5. A power supply device according to claim 4, wherein a plurality of the power supply devices are connected in parallel to an AC power supply, and each switch means operates at a different operation timing by a delay means of each of the power supply apparatuses. Characteristic power supply system.