JPH0385469A - Method of diagnosing fault of coil current supply circuit for linear motor - Google Patents

Abstract

PURPOSE:To always diagnose trouble during the operation of a circuit by passing a current supply cable itself or only the earth wire thereof through a through type current transformer to take balance so that no large output appears in the current transformer and throwing off the balance at the time of the trouble of the cable. CONSTITUTION:A pair of current supply terminal 3 and a pair of current supply cables 7 are respectively connected to a coil 1 for a linear motor having a semiconductive outer shield 2 and each of the cables 7 consists of a cable conduc tor 4, an insulator 5 and a metal shielding sheath 6. All of them are collectively inserted in a through type current transformer CT 8. The sheath 6 is earthed on the side of the coil 1 by an earth wire 9. The supply current of the coil 1 is cancelled by input/output and does not appear in the CT 8 but, when the cable 7 generates dielectric breakdown at the part below the CT 8, a current flows in the sheath 6 to flow to the earth line 9 and is caught by the CT 8 to become the output thereof. This output is detected to be transmitted to make it possible to detect a fault during the operation of a circuit.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a failure diagnosis system for linear motor coils.

[Prior Art and Problems to be Solved by the Invention] Conventionally, no practical examples of failure diagnosis for energizing circuits of linear motor coils have been published.

In underground capacitor systems, there are examples of faults being detected by inserting a through-type current transformer into the cross-bonded grounding wire.
The same method cannot be used to detect accidents in a current-carrying circuit connected to a linear motor coil that has only a semi-conductive external shield.

An object of the present invention is to invent a system that allows fault diagnosis of a coil energizing circuit for a linear motor to be carried out at all times during operation, and to make the system useful for maintenance of the coil system of a linear motor car.

[Means for Solving the Problems] In this invention, in order to diagnose the failure of the current-carrying circuit of the coil for a linear motor, a through-type transformer is used to cancel the influence of the pulse-like and large-amplitude coil current flow. Flushware (
CT). They are divided into two cases.

One is a case in which the current-carrying cable itself is passed through the feed-through current transformer, and the other is a case in which only the current-carrying cable grounding wire is passed through the feed-through current transformer.

In both of these, a feedthrough current transformer (C
The balance is maintained so that a large output does not appear on T), and in the event of a cable failure, the balance is disrupted and an accident can be detected.

Embodiments] The present invention will be described in detail below based on the drawings. 1st
The figure is a side view showing the configuration of a failure detection circuit when a current-carrying cable is passed through a feedthrough current transformer (CT). The linear motor coil 1 has a semi-conductive external shield i2, and the power supply terminals (input/output terminals) 3, 3 are connected to the current-carrying cables 7 and 7.
are connected to each other. A pair of current-carrying cables 7.7 are connected to cable conductors 4. Insulator 5. Each of them is composed of a metal shielding sheath 6. Then, these are bundled together and inserted into a through-type current transformer (CT) 8. The metal shielding sheath 6 of the current-carrying cable 7.7 is grounded by a grounding wire 9 at a portion closer to the linear morph coil 1 than the through-type current transformer.

The current flowing through the linear motor coil 1 is canceled between the input and output and does not appear in the feedthrough current transformer 8, but in FIG.
) 8, current will flow into the metal sheath 6 and into the ground wire 9. This current is caught by the feedthrough current transformer 8 and becomes the output of the feedthrough current transformer 8.

By detecting and transmitting this output, failure detection can be performed.

Also, even if both energizing cables 7.7 fail at the same time,
The current flowing through each metal shielding sheath 6 is in the same direction and can therefore be detected. At this time, the output of the through-type current transformer 8 becomes larger than the failure of the negative current-carrying cables 7.

Figure 2 shows a failure detection circuit when the energizing cable 7 is not passed through the feedthrough current transformer 8, but instead the grounding wire 9 is passed through the feedthrough current transformer 8. The other end of the linear motor coil 1 is connected to the adjacent linear motor coil 1a by a current-carrying cable 7a, and the other end of the linear motor coil 1a is connected to the adjacent linear motor coil 1 by a current-carrying cable 7b. Coil 1
b are sequentially connected in series. Also, cable 7.
Only one end of the metal sheaths 7a, 7b, 7c, . . . is grounded by a grounding wire 9. And energized cables 7.7a, 7
b, 7c, . . . make the linear motor coil 1.
When power is applied to la, lb, ..., the linear motor coils la, lb.

・Connection cables 7.7a, 7b on both sides.

A voltage is applied between the conductor 7c, . Therefore, in this case, the left and right connection cables 7.7a or 7b, 7.
One of the grounding wires 9 of c, .

In FIG. 2, it is possible to detect a failure in only one cable, but it is difficult to detect a failure in both cables at the same time. When the linear motor coil has a metallic external shield, if this shield is connected to the metal sheath on either side of the connecting cable, the current will be output to the through-type current transformer even in the event of a coil failure.

In addition, linear motor coil 1. la, lb.

・If there is a distance between them, connect the connecting cables 7.7a and 7.
b, ... becomes longer, and if one end is grounded, a high voltage may be induced at the ungrounded far end of the sheath.
It is necessary to install an arrester 11 to suppress the generated voltage. However, since the current-carrying cable of the current-carrying circuit of the linear motor coil is not very long, it is generally considered that an arrester is not necessary.If it is necessary to ground both ends of the 0-carrying cable, it is necessary to prevent the sheath circulating current from flowing. Consideration must be taken, such as placing a high resistance in the ground and grounding it.

[Effects of the Invention] As explained above, according to the method for diagnosing a fault in a coil energizing circuit for a linear motor according to the present invention, it becomes the first system capable of diagnosing a fault in a coil energizing circuit for a linear motor. In particular, the later method of inserting the grounding wire into the feedthrough current transformer can be applied even after the linear motor coil has been installed, and it is very economical as it allows the use of a feedthrough current transformer with a small core. .

(2) According to the fault diagnosis method of the present invention, since the system can be constantly diagnosed during operation, maintenance of the linear motor car coil energizing circuit system can be completely unmanned.

■By combining this application by the same applicant with the method for diagnosing linear motor coils filed on the same day, it is possible to unattended maintenance of the entire ground coil system of a ground linear motor car.

It is also a great feature that the detection circuit 9 judgment circuit can be used in common with the through-type current transformer for diagnosing the linear motor coil and the through-type current transformer for diagnosing the energizing circuit.

[Brief explanation of drawings]

FIGS. 1 and 2 are diagrams showing detection devices of the energizing cable penetration method and the cable grounding wire penetration method to which the fault diagnosis method for a coil energization circuit for a linear motor of the present invention is applied. 1, la, lb... Linear motor coil 2... Semi-conductive external shield 3... Power supply terminal 4... Cable conductor 5... Cable insulator 6... Cable metal shield Sheaths 7, 7a, 7b, 7c... Current-carrying cable 8... Penetration type current transformer (CT) 9... Grounding wire O... Grounding bus bar 1... Arrester

Claims (3)

[Claims] (1) When grounding one end of a metal-shielded connection cable that supplies power to a linear motor coil, energize by passing two adjacent cables or the grounding wires of the cables together into a through-type current transformer. A method for diagnosing a fault in a coil energizing circuit for a linear motor, which detects a fault by determining the output generated in the feedthrough current transformer at the time of a circuit fault. (2) Pass the two cables that feed the linear motor coil together into a feed-through current transformer, and ground the two cables on the linear motor coil side of the feed-through current transformer. A method for diagnosing a fault in a coil energizing circuit for a linear motor according to claim (1). (3) Energizing the coil for a linear motor according to claim (1), wherein the grounding wires of the two cables that feed power to the coil for the linear motor are reversed in direction and are passed through the through-type current transformer all at once. Circuit fault diagnosis method.