JPS62141922A - Protector for thyristor converter - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] This invention relates to a protection device for a thyristor converter.

[Conventional technology]

FIG. 2 is a block circuit diagram of a conventional thyristor converter mining device shown in, for example, Japanese Patent Publication No. 52-98920. 3 is DC motor material (DCM)
etc. to the load 4.

5 is an ACCT (current transformer), 6 is a current sensor, 7 is a voltage sensor, 8 is a current controller, 9 is a voltage controller,
10 is a gate pulse generator, and 11 is a gate cutoff circuit.

Next, the operation will be explained. First, the current sensor 6
It receives the output of CT5 and outputs a current feedback signal IF. The current controller 8 compares the current reference signal Is with the current feedback signal IF and amplifies the deviation;
Zero-order voltage controller 9 that outputs voltage reference signal VS
is the voltage feedback signal V which is the output of the voltage sensor 7
F and the voltage reference signal VS are compared and amplified to obtain a phase signal ps.
□Output. A gate pulse generator 10 receives the phase signal PS and generates a gate pulse GP to control the phase of the thyristor converter 1. The gate cutoff circuit 11 uses a current feedback signal IF and a gate cutoff current reference IGP.
When the condition of IF>IGPS is satisfied, a gate pulse cutoff signal GPS is outputted, and the gate pulse generator 10 stops the gate pulse GP by this gate pulse cutoff signal GPS.

[Problem that the invention seeks to solve]

Since the conventional protection device for a thyristor converter is configured as described above, there is no protection against the temperature rise of the thyristor element in the thyristor converter 1, and if the cooling function of the thyristor element stops or becomes insufficient. However, there were problems such as damage to the device, such as destruction of the device.

This invention was made in order to solve the above-mentioned problems, and a heat-sensitive element is installed as a means of protecting the element against abnormal temperature rise of the thyristor converter. The purpose of this invention is to obtain a protection device for a thyristor converter that controls the gate pulse that is the output of the thyristor converter.

[Means for Solving the Problems] A protection device for a thyristor converter according to the present invention includes a heat-sensitive element attached to a cooling fin for cooling a thyristor converter that converts an AC input into a DC input, The abnormal temperature rise of the thyristor element is detected by comparing the output of the thyristor element with a temperature reference value, and the gate pulse supply to the thyristor element is stopped.

[For production]

To protect the thyristor converter in this invention, a heat sensitive element is attached to the cooling fin, and when the abnormal temperature sensing signal from the heat sensitive element exceeds a predetermined value, a gate cutoff signal is output to immediately stop the operation of the thyristor converter. .

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. In FIG. 1, the same parts as in FIG. 2 are indicated by the same reference numerals. In FIG. A temperature sensor 11A that receives an output and obtains an electrical signal such as voltage is a gate cutoff circuit that compares the output signal TF of the temperature sensor 13 with a temperature setting reference signal TS, and when TF > TS, a gate cutoff signal GPS is generated. is generated, and the output gate pulse GP of the gate pulse generator 10 is stopped.

Next, the operation will be explained. First, thyristor converter 1
Protection against an abnormal temperature rise of the thyristor elements inside the device is done as follows. As the temperature of the thyristor element increases, the characteristics of the heat sensitive element 12 attached to its cooling fin change. In other words, when the heat-sensitive element 12 is a PTC positive temperature coefficient thermistor, the resistance value increases. This characteristic change of the heat sensitive element 12 is converted into a voltage level temperature signal TF by the temperature sensor 13, and is inputted to one terminal of the gate cutoff circuit 11A. Since the temperature setting reference signal TS is input to the other terminal of the gate cutoff circuit 11A, the gate cutoff circuit 1
At 1A, the two forces are compared, and if the thyristor element cooling fin temperature TF exceeds the set reference temperature TS, a gate cutoff signal GPs is generated. As a result, the outputs from the gate pulse generator 10 (-)), (-), and (-) GP are stopped, and the Cyrisk converter 1 stops energizing to protect the Cyrisk element.

In addition, although the above embodiment shows a protection control system that stops the gate pulse to the thyristor element when the temperature of the thyristor element cooling fin in the thyristor converter 1 rises abnormally, the protection control system is not used as a normal stop signal for the thyristor converter. It's okay.

Furthermore, it may be used as a cutoff signal for a switch that cuts off the AC or DC side main circuit of the thyristor converter.

〔Effect of the invention〕

As described above, according to the present invention, the circuit is configured to detect an abnormal temperature rise in the thyristor of the thyristor converter using a heat-sensitive element and stop the energization of the thyristor element, thereby providing a highly reliable protection device for the thyristor converter. There is an effect that can be obtained.

[Brief explanation of drawings]

FIG. 1 is a circuit configuration diagram of a protection device for a thyristor converter according to an embodiment of the present invention, and FIG. 2 is a circuit configuration diagram showing an example of a conventional protection device for a thyristor converter. In the figure, 1 is a thyristor converter, 12 is a heat-sensitive element,
13 is a temperature sensor, 11A is a gate cutoff circuit, 10
is a gate pulse generator. Patent Applicant Mitsubishi Electric Co., Ltd. Agent Patent Attorney 1) Hiroshi Sawa (2 others) Figure 1 11A:ff'-)-L Yayo'rDOZI Figure 2 Procedural Amendment (Voluntary) 1. Indication of the case Patent Application No. 60-280527 2.
Invention 0 Title: Protection device for thyristor converter 3, Representative of the person making the correction: Moriya Shiki 5, Detailed description of the invention in the specification to be amended! 131.3.2 Ended 6. The statement of contents of the amendment is amended as follows.

Claims (1)

[Claims] In a thyristor converter that performs power conversion using a thyristor element, a heat sensitive element attached to a cooling fin that cools the thyristor element is compared with an output signal of the heat sensitive element and a temperature reference value, and the output signal of the heat sensitive element is determined. 1. A protection device for a thyristor converter, comprising: a gate cutoff circuit that stops supplying a gate pulse signal to the thyristor element when a predetermined temperature reference value is exceeded.