JPH08289472A - Power supply controller - Google Patents

Abstract

PURPOSE: To feed a plurality of circuit in parallel with a rectified and smoothed current by connecting a plurality of switching regulators and inverters in parallel and providing a common active filter on the primary. CONSTITUTION: A switching regulator 2 is connected in parallel with a plurality of inverters 3, 4 requiring rectification and smoothing and a common active filter 5 is provided on the primary. Current from an AC power supply 1 is rectified and smoothed through the active filter 5 and only specified frequency components are passed. Since only one active filter 5 is required, overall size is reduced along with the cost.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power supply control device having a plurality of circuits requiring rectification and smoothing, and more particularly to a device suitable for application to a power supply control device such as a vending machine.

[0002]

2. Description of the Related Art For example, in a vending machine, an AC
In order to rectify and smooth the current from the power source and supply it to various control circuits, for example, a configuration as shown in FIG. 3 is adopted. In FIG. 3, 101 is an AC power source (for example, 100
V AC power supply), and the AC power supply 101 includes a switching regulator 102, inverters 103, 1
04 are connected in parallel. The switching regulator 102 and the inverters 103, 104 have rectification / smoothing circuits 105, 106, 107 incorporated therein or on their primary sides, and rectified / smoothed DC voltage (for example, on the secondary side). DC140V) can be supplied.

The rectifying / smoothing circuit is, for example, as shown in FIG. 4, a bridge circuit 108 of elements and an electrolytic capacitor 10.
9 and a rectified and smoothed direct current is provided in the switching regulator 102 and the inverter 1.
It is used as a primary side current of 03 and 104. The DC voltage controlled by the switching regulator 102 and the inverters 103 and 104 is used as a power supply voltage for various control circuits.

On the other hand, an active filter (active)
The pass filter is being used in various devices as a frequency selective circuit that allows electric power in a specific frequency band to pass and blocks electric power in other frequencies. In particular, when the regulation of harmonic current is about to be established in recent years, it is attracting attention as a powerful filter capable of blocking the harmonic current.

Since this active filter also has functions of rectification and smoothing, the switching regulator 102, the inverters 103, 1 of the circuit shown in FIG.
If each is provided on the primary side of 04, the rectification and smoothing circuits 105, 106 and 107 are not required.

[0006]

However, when the active filters are provided for the switching regulators 102 and the inverters 103 and 104 as described above, the number of active filters to be installed increases, the circuit board becomes large and the cost is high. There is a problem that it will become something.

The object of the present invention is to pay attention to the excellent function of the active filter concerning the countermeasure against harmonics, the rectification and the smoothing function, and make the most efficient use thereof to have the desired rectification and smoothing function, and An object of the present invention is to provide a power supply control device that can comply with harmonic current regulation and can be implemented at low cost.

[0008]

A power supply control device of the present invention which meets the above object is a power supply control device having a plurality of circuits which require rectification and smoothing, and an active filter common to the primary side of the plurality of circuits. It is characterized by being provided.

The power supply control device according to the present invention is suitable for application to, for example, an automatic vending machine. That is, the vending machine according to the present invention is a vending machine including a power supply control device having a plurality of circuits that require rectification and smoothing, and a common active filter is provided on the primary side of the plurality of circuits. It consists of features.

[0010]

In such a power supply control device, a plurality of circuits that require rectification and smoothing, that is, the above-mentioned switching regulators and inverters are provided in parallel, and a common active filter is provided on the primary side thereof. The current rectified and smoothed by the active filter is
It is supplied to the plurality of circuits. Since only one active filter is required, the overall circuit configuration can be simplified and the cost can be reduced.

Moreover, since the active filter passes only the current in the specific frequency band as described above, the harmonic current having an integral multiple of the fundamental frequency can be easily and accurately cut, and the harmonic current regulation can be ensured. Can be dealt with.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the power supply control device of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram of a power supply control device according to an embodiment of the present invention.
In the figure, 1 indicates an AC power supply (for example, 100 V AC power supply), and 2 indicates a switching regulator including, for example, a DC-DC converter. In this embodiment, a plurality of inverters 3 and 4 that require rectification and smoothing are provided in parallel with the switching regulator 2. The current (voltage) controlled by each switching regulator 2 and inverters 3 and 4 is supplied to each control circuit in, for example, an automatic vending machine (not shown).

A common active filter 5 is provided on the primary side of the switching regulator 2, the inverters 3 and 4, which require rectification and smoothing. Therefore, the current from the AC power supply 1 is rectified and smoothed by the active filter 5, and then supplied in parallel to the switching regulators 2 and the inverters 3 and 4.

Further, since the active filter 5 passes only the current in the specific frequency band, the harmonic current having a frequency which is an integral multiple of the predetermined fundamental frequency is
It is surely cut.

By using the active filters 5 in common as described above, the number of the active filters 5 is only one, and the circuit configuration of the entire power supply control device can be made extremely simple as compared with the case where a plurality of active filters 5 are provided. Therefore, it is possible to reduce the size and cost of the entire device.

Further, since the harmonic current can be cut off reliably and efficiently on the primary side of each circuit, it is possible to easily and surely comply with the regulation of the harmonic current.

FIG. 2 shows a modification of the circuit configuration shown in FIG. That is, the active filter 11 is
It is built in a switching regulator 13 having a DC-DC converter 12, and the switching regulator 13 itself has a function of an active filter. The output from the circuit of the active filter 11 portion of the switching regulator 13 is provided to the inverter 1 arranged in parallel with the switching regulator 13.
4, 15, etc. are supplied to other circuits that require rectification and smoothing.

As described above, even if an active filter is incorporated in any circuit that requires rectification and smoothing and the rectified and smoothed current is supplied from that to another circuit or device, the active filter is also used. Can be standardized.

Even with such a structure, basically the same operation and effect as those shown in FIG. 1 can be obtained.

Although the vending machine has been illustrated as a device to which the power supply control device according to the present invention can be applied, the device is not limited to this, and a device including a power supply control device having a plurality of circuits that require rectification and smoothing. If so, the present invention can be applied to basically any device.

[0021]

As described above, according to the power supply control device of the present invention, a common active filter is provided on the primary side of a plurality of circuits that require rectification and smoothing.
It is possible to efficiently perform desired rectification and smoothing with a single active filter, and it is possible to configure the entire power supply control device in a small size and at low cost.

Further, due to the function originally possessed by the active filter, it is possible to easily and surely deal with the regulation of harmonic current.

[Brief description of drawings]

FIG. 1 is a block diagram of a power supply control device according to an embodiment of the present invention.

FIG. 2 is a block diagram of a power supply control device according to a modification of FIG.

FIG. 3 is a block diagram showing an example of a conventional power supply control device.

FIG. 4 is a circuit diagram showing an example of a rectifying / smoothing circuit.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 AC power supply 2, 13 Switching regulator 3, 4, 14, 15 Inverter 5, 11 Active filter 12 DC-DC converter

Claims (2)

[Claims] 1. A power supply control device having a plurality of circuits requiring rectification and smoothing, wherein a common active filter is provided on a primary side of the plurality of circuits. 2. A vending machine provided with a power supply control device having a plurality of circuits requiring rectification and smoothing, wherein a common active filter is provided on the primary side of the plurality of circuits. .