SU1432659A1 - Device for protecting power-diode converter - Google Patents

Abstract

The invention relates to electrical engineering. The aim of the invention is to simplify the device for protecting the converter and extending its functionality. The valve Converter 1 through the network reactor 2 is connected to the AC network. Valve conductivity sensor 3 and current sensor 4 through element 5 and delay element 6 are connected to the blocking input of valve converter 1. At an interruption of phase or breakdown of the valve, at the inputs of element 5, two signals of logical zero appear at the moments when there is no current in the load. At the same time, the output signal of the element 5 through the delay element 6 is fed to the blocking input of the valve converter 1. The goal is achieved by reducing the number of circuit elements and providing an additional possibility of monitoring the operability of the converter valves. 2 Il. (L

Description

connected to the pre-JQ blocking inputs. Time delay value, counted35

40

Former 1, the output of which is connected to the load (electric motor) 7.

The Converter operates as follows.

A reverse VP 1, consisting of two sets of thyristors, is controlled according to the principle of separate control and feeds the load 7. The conductivity sensor 3 monitors the operation of the thyristors, the output of which has a logical signal 1 in the absence of valves turned on or O in the presence of valves turned on. In this case, the signal O prohibits the switching of sets of thyristors. Monitoring the current value of the VP 1 is implemented using the current sensor 4. When the output signal of sensor 4 is exceeded by the set value in VP 1, the overcurrent protection trigger is activated and the operation of VP 1 is inhibited.

In the absence of damages in VP 1, the signals at the outputs of sensors 3 and 4 have opposite values — 1 and O (Fig. 2), and the output signals Uj, and coincidence element 5 and element 6 of delay time are early 1.

50

55

element 6 depends on the sensitivity of the conduction sensor 3 and is 0.2-1 ms.

Claims (1)

Invention Formula A device for protection of a valve converter, equipped with three blocking inputs, containing a valve conductivity sensor, functioning as a function of the voltage on monitored valves, and a converter input current sensor, whose outputs are intended for connection, respectively, to the first and second blocking inputs of the converter, and a time delay element characterized in that, in order to simplify and extend the functionality, a coincidence element is introduced, the inputs of which are connected to the outputs d tchikov valves and input current conduction verters transformations, and an output connected to the input of delay element whose output is intended for connection to a third input of the blocking converter. Time delay counting This element 6 depends on the sensitivity of the conductivity sensor 3 and is 0.2-1 ms. Invention Formula A device for protecting a valve converter equipped with three blocking inputs, containing a valve conductivity sensor, operating as a function of the voltage on monitored valves, and a converter input current sensor, whose outputs are intended for connection, respectively, to the first and second blocking inputs of the converter, and the element delay time, characterized in that, in order to simplify and extend the functionality, an element of coincidence is introduced, the inputs of which are connected to the outputs tchikov valves and transducer input current conduction, and an output connected to the input of delay element whose output is intended for connection to a third input of the blocking converter. r Editor N.Lazarenko Compiled by V.Shirokov Tehred M. Didyk Order 5455/49 Circulation 651 VIIIPI State Committee of the USSR on affairs of inventions and discoveries 113035, Maskva, Zh-35, Raushsk nab., 4/5 Figg Proofreader I. Muska Subscription