SU938209A1 - Device for checking presence of n-phase rectifying bridge short-circuiting to ground - Google Patents

Description

(54) DEVICE FOR CONTROL OF AVAILABILITY OF KOPOTKOrd CLOSING ON THE EARTH OF A H-PHASE RELATIVE BRIDGE

one

The invention relates to electrical measuring technology and can be used by the OLE to control the presence of a short circuit to the ground rectifier by switching it on.

It is known a device for monitoring the presence of grounding and blocking the switching on of a high voltage source, containing block contacts, kinematically connected with a gas borrowed by a razdashitel knife. Checking the presence of grounding is carried out by electrically and mechanically controlling said block contacts.

A disadvantage of this device is the relatively low reliability of the motor with the presence of movable mechanical links between the auxiliary contacts and the grounding knife. In addition, the device does not control the presence of an electrical contact in the ground circuit.

The closest in technical essence is a device for blocking the on-switch of the rectifier switch.

containing the source of operating current, the fixing body of the presence of operating current, the actuating element of which is included in the circuit of the command to turn on the switch and the element of the driver of the actuator of the operating current to the power source; In addition, the HMeeTCja switch with three contacts, and its opening contact is switched on by the specified element and the earth, and in parallel with it are connected in series the first closing contact of the switch, the organ of fixing the presence of the operational current, the source of the operational current a and the second closure contact switch.

Claims (2)

A disadvantage of this device is the need to use an additional high-voltage alement connected to the operating current source to the rectifier. A switch that disconnects this element from the ground and connects the power source to the operating unit (Ms. "conditionally and reduces the reliability of the device. These deficiencies are especially significant in low-power power supplies, the fashionability and dimensions of which are commensurate with the power and dimensions of the specified element. Purpose of the invention - to simplify and increase the reliability of the device. This goal is achieved by the fact that the device for controlling the presence of a short circuit to earth has a P-phase direct bridge containing a switchgear with interrupting blocking contact, connected between the controlled and and phase rectifying bridge and the AND -phase source of alternating current voltage, the control unit of the operating current, one of the terminals of which is connected to the positive terminal of the operating current source, an additional diode is inserted into it direction as the diodes of the controlled z-phase surge bridge, and the additional diode is connected to one of the terminals of the control current control unit and the anode to the negative terminal ika control current. The drawing shows an aleKIrichesky scheme of the device for controlling a two-phase rectifying bridge. It consists of a controlled rectifier bridge 1, a block 2 of control current current, a source of 3 operating current, a switch 4 with a block contact, an additional diode 5. The dotted line 6-7 shows the circuit of a possible short circuit in the load of the rectifier. The device works as follows. , In the presence of a short circuit on the ground of the switched off rectifying bridge, the operating current circuit closes through the normally closed block contact of switch 4, rectifying bridge I periods, and the circuit of the retracting circuit (para 6–7). As a result, block 2. The control of the operating current signals an inadmissible switch-on of the rectifier. In the absence of a short-circuit to earth, the control current circuit is open, the control unit fails to signal a signal prohibiting the switch-on of the rectifier. When you turn on the rectifier block94, the contact off-hook 4 turns off the source. nick 3 operating current, preventing the flow of rectified current through the control circuit. The rectified current flows through diode 5. Since the direct voltage drop across diode 5 is small, all elements of the control circuit are on a safe low potential, close to the ground potential. The application of this invention allows to simplify the design and increase the reliability of the device for monitoring the presence of grounding (L-phase rectifier, due to the absence of additional alement of connecting the high-voltage circuit to the source of operating current, as well as a switch connecting this element to the common ground terminal. Formula for Control Device the presence of a short circuit to earth and a phase-interrupting bridge - containing a switch with an opening blocking contact connected between monitored m and a phase voltage bridge and an ac voltage source, the control current control unit, one of the conclusions of which is connected to the plc top of the control current source, characterized in that, in order to simplify the construction and increase reliability, An additional diode is introduced in the same direction as the diodes of the monitored and -phase rectifying bridge, with the cathode of the additional diode connected through one of the disconnecting block congdt to one of the outputs of the electrodatrol unit, and the anode to the kin The usable output of the operating current source. Sources of information taken into account in the examination I. Rules of technical operation of power plants and networks. Gosenergoizdat, 1963, § 734. 2. USSR author's certificate N 614494, cl. H 02 H 11 / OO, 1976 (prototype).