JP3298311B2 - Surge protection circuit for servo driver - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a discharge tube type surge absorbing component used for a surge protection circuit of a servo driver having a power circuit portion and a control circuit portion, and a nonlinear resistance element mainly composed of zinc oxide. The present invention relates to a surge protection circuit including a surge absorbing component.

[0002]

2. Description of the Related Art In recent years, demand for servo drivers has been increasing with the development of power electronics technology. In the servo driver, when power is simultaneously supplied to the power circuit unit and the control circuit unit, the motor may rotate several tens of degrees for a moment. As described above, in a case where the rotation of the motor is inconvenient, power is supplied to the control circuit, and after the control voltage is stabilized, power is supplied to the power circuit. When the power is turned off, the power supply must be turned off after turning off the power circuit power first. In addition, when the input power of the power circuit unit and the control circuit unit is cut off at the same time when the servo driver is abnormal, the detector (encoder) power for detecting the rotation position of the motor is not supplied, and the rotation position of the motor is calculated as a relative value. If the detector (encoder) detected by is used, the home position return operation must be performed to recognize the rotational position of the motor when the power is turned on again. Therefore, when the input power of the control circuit unit is cut off and turned on again in the middle of the determined operation pattern, work cannot be started from the cut off operation pattern. To prevent such inconveniences as much as possible, the servo driver is configured such that the input power supply is divided into a power circuit and a control circuit.

A conventional surge protection circuit will be described below. FIG. 2 shows a conventional surge protection circuit. 2 in FIG.
Is a three-phase or single-phase power circuit (main circuit) power supply, 2 is a converter section of the power circuit (main circuit), 3 is an inverse conversion section (inverter section), 4 is a servomotor, and 51 is a power circuit (main circuit). , 6 is a single-phase control circuit power supply, 7 is a converter section of the control circuit, and 8 is a surge protection circuit of the control circuit. Here, the surge protection circuits 51 and 8 are composed of a surge absorbing component of a non-linear resistance element containing zinc oxide as a main component and a surge absorbing component of a discharge tube type. Normally, a surge protection circuit inserts a surge absorbing component of a non-linear resistance element containing zinc oxide as a main component between each line of a power supply, and zinc oxide as a main component between one phase of a power supply and a frame ground (FG). A series of non-linear resistance element surge absorbing components and discharge tube type surge absorbing components are inserted.

Accordingly, it can be understood from the above that a servo driver which requires two systems, a power circuit (main circuit) power supply and a control circuit power supply, requires a surge protection circuit.

[0005]

As described above, a servo driver requiring two systems, a power circuit (main circuit) power supply and a control circuit power supply, requires a zinc oxide between one phase of the power supply and a frame ground (FG). It is necessary to insert a series connection of a surge absorbing component of a non-linear resistance element and a surge absorbing component of a discharge tube type, each of which is mainly composed of: Therefore, since the surge absorbing component of the discharge tube type was attached to each of the power supply for the power circuit and the power supply for the control circuit, the weight of the surge protection circuit in the substrate area of the power section was relatively high.

[0006]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems and provides a power circuit (main circuit) power supply and a control circuit power supply.
When inserting a surge absorbing component of a non-linear resistance element mainly composed of zinc oxide and a surge absorbing component of a discharge tube type between the phase and the frame ground (FG) into the series, the surge absorbing component of the discharge tube type is connected to the power circuit ( It is composed of a surge protection circuit inserted so as to be shared by both power supplies for the main circuit) and the control circuit.

[0007]

According to the structure of the surge protection circuit, the area of the surge protection circuit occupying the substrate area of the power section of the servo driver which requires both the power circuit (main circuit) power supply and the control circuit power supply is reduced. The configuration of the surge protection circuit can be made inexpensive and the size of the servo driver can be reduced.

[0008]

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a surge protection circuit for a servo driver according to the present invention. The basic structure of the surge protection circuit is the same as the conventional surge protection circuit shown in FIG. The difference of the surge protection circuit of the present invention is that, as shown in FIG. 1, zinc oxide is a main component between each phase of the power circuit (main circuit) power supply 1 and the control circuit power supply 6 and the frame ground (FG). When inserting the non-linear resistance element surge absorbing component and the discharge tube type surge absorbing component into the series, the discharge tube type surge absorbing component is connected to both the power supply 1 for the power circuit (main circuit) and the power supply 6 for the control circuit. Is to be shared by Thus, the area of the surge protection circuit occupying the substrate area of the power portion of the servo driver can be reduced, the configuration of the surge protection circuit can be reduced, and the size of the servo driver can be reduced.

[0010]

As described above, in the servo protection circuit of the present invention in a servo driver requiring both power supply (main circuit) power supply and control circuit power supply, the power supply and the frame ground (FG) can be provided. A discharge tube type surge absorbing component used in the surge protection circuit (a series connection of a discharge tube type surge absorbing component with a non-linear resistance element surge absorbing component containing zinc oxide as the main component) and a dual power supply By reducing the area of the surge protection circuit occupying the substrate area of the power section of the servo driver, the configuration of the surge protection circuit can be reduced and the size of the servo driver can be reduced.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a surge protection circuit of a servo driver according to an embodiment of the present invention.

FIG. 2 is a diagram illustrating a surge protection circuit of a conventional servo driver.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Power supply of main circuit (3 phase and single phase) 2 Converter part of main circuit 3 Inverting part 4 Servo motor 5, 51 Surge protection circuit 6 Control circuit power supply 7 Converter part of control circuit 8 Surge protection circuit of control circuit

──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Yoshifumi Funabashi 1006 Kazuma Kadoma, Osaka Prefecture Inside Matsushita Electric Industrial Co., Ltd. (56) References JP-A-5-95632 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H02H 9/04 H02M 7/48 H02P 7/63

Claims (1)

(57) [Claims] 1. A power converter for converting an AC input to a DC output.
Driver with power supply for road and power supply for control circuit
, One phase of the power supply for the power circuit and the control circuit
Between zinc and frame ground (FG)
Surge absorbing component of non-linear resistance element
Connect the surge absorbing parts of Ip to the series and
A surge protection circuit for servo drivers that uses a two-pole discharge tube type surge absorbing component for the road.