JP2009148016A - Common printed circuit board and dc power supply circuit using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a common printed board compatible with both single-phase input and three-phase input and constitutes a desired DC power supply circuit inexpensively. <P>SOLUTION: A motor drive performs power conversion of single-phase input into DC output by means of a two-phase diode bridge 2. A smoothing capacitor 6 is connected to the output of the two-phase diode bridge 2, and a motor current is controlled by switching operation of an inverter section 7 using the DC voltage as a power supply and then controlling a voltage to be applied to a motor 8. A DC power supply circuit 1 is from input terminals R, S, T to the smoothing capacitor 6. The two-phase diode bridge 2 includes a first full-wave rectifier circuit 2a and a second full-wave rectifier circuit 2b. A current interruption fuse 4 is arranged between the input terminal R and the first full-wave rectifier circuit 2a and a current interruption fuse 5 is arranged between the input terminal T and the second full-wave rectifier circuit 2b. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention uses a common printed circuit board for a power supply circuit that converts a single-phase input or a three-phase input into a DC output by interposing at least one current interruption type fuse between a single-phase input and an input of a two-phase diode bridge. Related to the DC power supply circuit.

  Industrial equipment may be used with a single-phase AC power supply or a three-phase AC power supply as an input, and a motor and a motor drive device that are drive sources of the equipment need to support both AC power supplies.

  Therefore, power conversion provided with a discriminating means for judging whether the AC power source as an input is a single-phase input or a three-phase input and an overcurrent change level means for changing the overcurrent level of the overcurrent protection circuit based on the discrimination result An overcurrent protection circuit for a device has been proposed (see, for example, Patent Document 1).

  2. Description of the Related Art In recent years, motor drive devices convert AC input into DC output, switch the inverter unit using a DC voltage connected to a smoothing capacitor as a power source, and control the voltage applied to the motor to control the motor current. In general, an inrush current suppression resistor that suppresses the charging current of the smoothing capacitor and a relay that short-circuits the inrush current suppression resistor after charging are provided on the DC line (for example, FIG. 3 of Patent Document 2). reference).

An overcurrent protection means is provided between one of the AC power supply terminals and one of the diode bridge input terminals in order to provide a highly safe power supply protection circuit that can cut off the AC power supply when the smoothing capacitor fails in the short mode. And what was provided with the relay connected to the both ends of an overcurrent protection means is proposed (for example, refer FIG. 1, FIG. 2 of patent document 2).
JP 60-134722 A JP 2007-236107 A

  Usually, a three-phase input DC power supply circuit can also handle a single-phase input. For this reason, even if it is a case where it uses by a single phase input, it is necessary to provide two current interruption type fuses. Further, depending on the connection method of the input terminals, a current interrupting fuse may be interposed on one or both phases.

  Since the two-phase diode bridge used for general household appliances is used in large quantities, it can be obtained at low cost. Current-blocking fuses are expensive compared to inexpensive two-phase diode bridges. If a new printed circuit board for single-phase input is installed, the cost increase due to current-blocking fuses can be eliminated, but the printed circuit board can be shared. It is not possible to increase the cost and to manage the printed circuit board. In addition, the use of two two-phase diode bridges can be configured at a lower cost than the use of a three-phase diode bridge.

  SUMMARY OF THE INVENTION The present invention solves the above-described conventional problems, and an object of the present invention is to provide a common printed circuit board that can cope with both a single-phase input and a three-phase input and that can configure a desired DC power supply circuit at low cost.

In order to solve the above-mentioned problem, the common printed circuit board according to claim 1 is a power supply circuit for converting a single-phase input or a three-phase input into a DC output by interposing at least one fuse between a single-phase input and a two-phase diode bridge. In order to connect the first two-phase diode bridge incorporating the first and second full-wave rectifier circuits and the two fuses, the input terminal R and the input of the first full-wave rectifier circuit ( The first fuse is disposed between the middle point) and the second fuse is disposed between the input terminal T and the input (middle point) of the second full-wave rectifier circuit. In order to connect the input terminal S to the second two-phase diode bridge incorporating the full-wave rectifier circuit, a pattern for connecting the input terminal S and the input (middle point) of the fourth full-wave rectifier circuit is provided. First full wave rectification Characterized in that a pattern for connecting the input (the midpoint) of the input and the third full-wave rectifying circuit of the road is disposed.

  According to a second aspect of the present invention, there is provided a DC power supply circuit according to the first aspect, a two-phase diode bridge incorporating the first and second full-wave rectifier circuits, and the first and second current interrupting fuses. A first current interrupting fuse is disposed between the input terminal R and the input of the first full-wave rectifier circuit, and a second current interrupting fuse is provided between the input terminal T and the input of the second full-wave rectifier circuit. Is arranged.

  According to a third aspect of the present invention, in addition to the second aspect, the DC power supply circuit includes a second two-phase diode bridge that incorporates the third and fourth full-wave rectifier circuits, and an input of the first full-wave rectifier circuit. (Middle point) and the input (middle point) of the third full-wave rectifier circuit are connected.

  A DC power supply circuit according to a fourth aspect includes the shared printed circuit board according to the first aspect, a two-phase diode bridge incorporating the third and fourth full-wave rectifier circuits, and a first current interrupting fuse, A first current interruption type fuse is disposed between the input terminal R and the input (middle point) of the third full-wave rectifier circuit, and the input terminal S and the input (middle point) of the fourth full-wave rectifier circuit are connected. ing.

  According to the shared printed circuit board of the first aspect, it is possible to deal with single-phase input and three-phase input with one type of printed circuit board, and a desired DC power supply circuit can be provided at low cost.

  According to the DC power supply circuit of the second aspect, compared to the conventional connection method in which current interrupting fuses are inserted on both sides of the three-phase input DC power supply circuit, only one two-phase diode bridge is required and the cost is low. Can be configured.

  According to the DC power supply circuit of the third aspect, compared to the conventional three-phase input DC power supply circuit, the input power supply R phase is configured to be connected to the first and third full-wave rectifier circuits. Reliability is improved.

  According to the DC power supply circuit of the fourth aspect, a single-phase input DC power supply circuit in which a current interrupting fuse is inserted on one side can be obtained at low cost without using a printed circuit board dedicated to single-phase input.

  Therefore, a desired DC power supply circuit can be provided at low cost for a single-phase input or a three-phase input with one type of printed circuit board.

In order to connect the first two-phase diode bridge incorporating the first and second full-wave rectifier circuits and the two fuses, the first fuse is input between the input terminal R and the input of the first full-wave rectifier circuit. A second two-phase diode bridge including a third fuse and a fourth full-wave rectifier circuit, each having a second fuse disposed between the terminal T and the input of the second full-wave rectifier circuit; In order to connect the input terminal S, a pattern for connecting the input terminal S and the input of the fourth full-wave rectifier circuit is provided, and the input of the first full-wave rectifier circuit and the input of the third full-wave rectifier circuit are arranged. It is a common printed circuit board provided with a pattern for connecting inputs. Hereinafter, embodiments will be described with reference to the drawings.
(Embodiment 1)
Embodiment 1 describes a DC power supply circuit in which current interrupting fuses are provided in both input phases of a single-phase AC power supply.

  FIG. 1 is a block circuit diagram of a main part of a motor driving apparatus using a DC power supply circuit of the present invention. In FIG. 1, the motor drive device includes three input terminals R, S, and T so that it can be connected to both an input single-phase AC power source and a later-described three-phase AC power source. 2 is a two-phase diode bridge, and 4 and 5 are current interrupting fuses. 6 is a smoothing capacitor, 7 is an inverter, and 8 is a motor. For the wiring pattern of the common printed circuit board, it is assumed that the wiring in the circuit diagram is substituted.

  The motor driving apparatus according to the first embodiment converts a single-phase input into a DC output by a two-phase diode bridge 2. A smoothing capacitor 6 is connected to the output of the two-phase diode bridge 2, and the inverter unit 7 is switched using this DC voltage as a power source to control the voltage applied to the motor 8 to control the motor current. The DC power supply circuit 1 is from the input terminals R, S, T to the smoothing capacitor 6.

  The two-phase diode bridge 2 includes a first full-wave rectifier circuit 2a and a second full-wave rectifier circuit 2b, and is connected between the input terminal R and the input (middle point) of the first full-wave rectifier circuit 2a. In addition, a current interruption type fuse 4 is disposed, and a current interruption type fuse 5 is arranged between the input terminal T and the input (middle point) of the second full-wave rectification circuit 2b.

With this configuration, in the single-phase input DC power supply circuit according to the first embodiment, two current interrupting fuses are interposed between the input terminal R and the input terminal T and the two-phase diode bridge. Compared with a conventional three-phase input DC power supply circuit (when a three-phase diode bridge is used), the DC power supply circuit can be configured at a low cost because it can be configured with one two-phase diode bridge. (Embodiment 2)
The motor drive apparatus according to the second embodiment is a DC power supply circuit in which a two-phase diode bridge 3 is added to the first embodiment in order to cope with three-phase input, and differences will be mainly described. FIG. 2 is a block circuit diagram of the main part of a motor driving apparatus using the DC power supply circuit of the present invention.

  In FIG. 2, two two-phase diode bridges are used to support three-phase input. For this reason, the two-phase diode bridge 3 having the same configuration as the two-phase diode bridge 2 is used. The two-phase diode bridge 3 includes a first full-wave rectifier circuit 3a and a second full-wave rectifier circuit 3b, and as shown in FIG. The input (middle point) of the full-wave rectifier circuit 3b is connected. This enables full-wave rectification of all three phases (R, S, T).

  Although only one two-phase diode bridge is used in the first embodiment, it cannot be explained. However, the shared printed circuit board according to the present invention is characterized by the two-phase diode bridge 3 and the wiring of the input terminal. is there. The shared printed circuit board of the present invention is a point that connects the input of the first full-wave rectifier circuit 3 a of the two-phase diode bridge 3 and the input of the first full-wave rectifier circuit 2 a of the two-phase diode bridge 2. With this wiring, the DC power supply circuit 1 of the first embodiment and the DC power supply circuit 11 of the second embodiment can be configured with one type of common printed circuit board.

According to the DC power supply circuit 11 of the second embodiment, the input R phase is connected to the two full-wave rectifier circuits, and the current is divided, so that the failure probability is low and the three-phase input with high reliability. Can be obtained.
(Embodiment 3)
The third embodiment is a DC power supply circuit in which a current interrupting fuse is provided in one input phase of a single-phase AC power supply. Conventionally, a dedicated printed circuit board has been required. By using the shared printed circuit board of the present invention, the current interrupting fuse 4 is interposed only on one phase side of the single-phase input.

  In this case, the two-phase diode bridge 2 and the current interrupting fuse 5 may be removed from the second embodiment, resulting in the DC power supply circuit 12 shown in FIG. Thus, an inexpensive single-phase input DC power supply circuit can be provided without newly installing a dedicated printed circuit board.

  As described above, by using the common printed circuit board of the present invention, it is possible to cope with a three-phase input and two types of single-phase inputs, and to provide a desired DC power supply circuit and a motor drive device using the same at low cost. Can do.

  The shared printed circuit board of the present invention is most suitable for a power circuit board of industrial equipment that uses an AC power supply as an input, and is also useful for a motor drive device having a power conversion circuit.

1 is a block diagram of a principal part of a motor drive device using a DC power supply circuit according to Embodiment 1 of the present invention. Main part block circuit diagram of motor drive device using DC power supply circuit in Embodiment 2 of the present invention Main part block circuit diagram of motor drive device using DC power supply circuit in Embodiment 3 of the present invention

Explanation of symbols

1, 11, 12 DC power supply circuit 2, 3 Two-phase diode bridge 2a, 2b, 3a, 3b Full-wave rectifier circuit 4, 5 Current interruption type fuse 6 Smoothing capacitor 7 Inverter section 8 Motor

Claims (4)

In a common printed circuit board for a power supply circuit that converts a single-phase input or a three-phase input into a DC output by interposing at least one fuse between a single-phase input and a two-phase diode bridge,
In order to connect the first two-phase diode bridge having the first and second full-wave rectifier circuits and the two fuses, the first terminal is connected between the input terminal R and the input (middle point) of the first full-wave rectifier circuit. A pattern is arranged so that a fuse can be installed between the input terminal T and the input (middle point) of the second full-wave rectifier circuit, respectively.
In order to connect the second two-phase diode bridge incorporating the third and fourth full-wave rectifier circuits and the input terminal S, the input terminal S and the input (middle point) of the fourth full-wave rectifier circuit are connected. A common printed circuit board comprising a pattern and a pattern connecting an input of the first full-wave rectifier circuit and an input (middle point) of the third full-wave rectifier circuit. The shared printed circuit board according to claim 1;
A two-phase diode bridge incorporating first and second full-wave rectifier circuits;
Comprising first and second current interrupting fuses;
A first current interruption type fuse is disposed between the input terminal R and the input (middle point) of the first full-wave rectifier circuit, and the second current-carrying fuse is connected between the input terminal T and the input (middle point) of the second full-wave rectifier circuit. A DC power supply circuit comprising a two-current interruption type fuse. And a second two-phase diode bridge incorporating the third and fourth full-wave rectifier circuits,
3. The DC power supply circuit according to claim 2, wherein an input (middle point) of the first full-wave rectifier circuit and an input (middle point) of the third full-wave rectifier circuit are connected. The shared printed circuit board according to claim 1;
A two-phase diode bridge incorporating third and fourth full-wave rectifier circuits;
A first current interrupting fuse;
A first current interrupting fuse is disposed between the input terminal R and the input (middle point) of the third full-wave rectifier circuit, and the input terminal S and the input (middle point) of the fourth full-wave rectifier circuit are connected. DC power supply circuit characterized by that.