MXPA96001020A - Device for supervision of paths of opening and closing signals in poten switches - Google Patents

Abstract

Electronic device for monitoring the correct state of an electrical circuit, which remains inactive most of the time, but which is important to know when it has failed, to take corrective measures. Its main application will be in the power switches to monitor the continuity over the paths in which the currents that energize the opening (trip) and closing coils should circulate, this supervision will not affect the normal operation of the circuit breaker. The device is composed of two sections, the first one is permanently connected to the opening control circuit of the circuit breaker. The second section is the main module with electronic components that perform the supervision function, which when inserted in its base is interspersed in the control circuit to perform its function and will generate a signal, closing dry contacts, when it detects a malfunction of the interrupt control circuit

Description

DEVICE FOR SUPERVISION OF PATHS OF SIGNALS OF OPENING AND CLOSURE OF SWITCHES OF POWER.

INVENTOR ING. MELITON ANGELES MARTÍNEZ.

MEXICAN NATIONALITY.

DOMICILIO AYOCUAN No. 123, COL. NETZAHUALCÓYOTL OAXACA DE JUÁREZ OAX., MEXICO. C.P. 68140.

R F C AEMM 530401 C68 DEVICE FOR SUPERVISION OF COILS OF CLOSURE OR OPENING OF POWER SWITCHES.

DESCRIPTION: The importance represented by the correct operation of a Power Switch in the processes of Generation, Transmission and Distribution of Electric Power, with operating voltages from 13.8 KV. up to 400 KV., either under normal operating conditions, but especially in cases of system failures, it is necessary to supervise the conditions of the firing scheme (opening and closing) associated with the switch that includes: * The coil Shooting. * The closing COIL. * The Control Cables. * The connections on the tablets. * The internal wiring of the Switch. * The internal blocking elements of the switch. The interruption in the trajectory of the trip circuit including the aforementioned components, represents an abnormal condition that will impede the operation of the circuit breaker at the most critical moment and the impossibility of operating a power breaker can be very costly for companies that they have them in service. In order to prevent and avoid these abnormal, dangerous, costly conditions and increase the reliability of the switches, the device object of this request was developed. The device is composed of two sections, a fixed module (1) and a plug-in module (2), as shown in figure 1; where the main elements of the device are shown. Connection board (3) 11-pin base (4) 8-pin base (5) Auxiliary relay (6) Metal box of the base module (1) contained in metal modules to work in areas with electric and / or magnetic fields High intensity. This version allows to supervise two trip coils and a closing coil, for application in monopolar or tripolar operation switches and that by means of a small rearrangement in the electronic components allows us to supervise three trip coils in monopolar operation switches; and it is designed to be installed in the control cabinet of the switch itself, or in the control panels in the control room. Figure 2 shows the base module, which is composed of: A terminal board of 12 terminals (3). A base of 11 terminals to plug in the second module (4). Cables to connect the different components. A metal box in which these components are contained (1). An 8-pin base for the auxiliary relay (5) Auxiliary relay for dry contacts (6). Fuse holder for fuse type glass encapsulation (10) Figure 2a shows the front of the metal case of the fixed module. Figure 2b shows the side view of the fixed module. Figure 3 shows the front view of the plug-in module. Figure 3 a shows a side view of the plug-in module. Figure 4 shows the electronic circuit for the supervision of two trip coils and one closing coil. Figure 4a shows the electronic circuit for the supervision of three trip coils. The electronic board contains elements such as rectifier diodes, light emitting diodes, zener diodes, capacitors, resistors, optical couplers and surge protection based on MOV, and 11 leg connector arranged in a circular way to plug (4).

The supervision is carried out by detecting a small current that circulates through the coil which produces a voltage drop and which is detected by the elements that remain in series with it. Zl allows to determine a voltage drop for this circuit. Ll signals the circulation of a minimum current of 2 milliamperes for this circuit. OT1 activates its output transistor to drive when it detects the same current. All the capacitors perform the function of absorbing the surges that could be induced in the circuit and avoiding damage to the components in parallel. The resistors in series with the optocouplers limit the circuit current to less than 5 milliamperes, so as not to trigger a shot through them. The arrangement of two resistors in series, separately and their dissipation power minimize the possibility of accidental firing due to component damage. The outputs of the optical couplers are connected in series to obtain a "and" gate that allows to energize the relay BR1 through the transistor TI when the supervised coils are correct, but a fault in any of them will cause the de-energization of the relay BR1 , which will also be activated by the lack of potential in the supervised circuit. In closed switch conditions, the trip circuit must be permanently ready to open, therefore there must be continuity in the trip path, which will cause the activation of the optical couplers, consequently activating TI and BR1 to keep their contacts open. output, but if any of the trip paths fails, the optical coupler of that phase will be deactivated deactivating TI and BR1, when de-energized BR1 will close its contacts to announce the failure presented in the supervised circuit. The output contacts of BR1 are completely isolated and can be connected to any annunciator, alarm box, supervisory control, programmable controller, etc. The device can be manufactured for different operating voltages simply by varying the values of the resistors in series with the optical couplers to maintain the same current values through them.

The device has a minimum current consumption of less than 20 milliamps, which represents a consumption of 2.5 watts at 125 volts, consequently eliminating overheating due to dissipation. It works as a low voltage relay (27), detecting the loss of potential. It can operate at room temperature from -10 to 70 ° C since its components are wide range. It is capable of detecting continuity in the trip trajectories including a wide range of impedance in the trip coil from 10 ohms up to 10,000 ohms. Immune to induced interference due to its design in a fully shielded module. Totally safe against unwanted trips caused by component failure, since it has very high impedance components in the supervision path, limiting the current to less than 5 milliamps per phase and with an optical coupling, between the supervision components and the of logic, whose insulation value reaches 7,500 VAC peak. The module can be removed at any time without interrupting the firing path. All the diodes are polarized directly, which decreases the possibility of damage in them also counting with a capacitive damping. It has signaling diodes (LEDs) that allow personnel to quickly locate the fault, (if the fault is internal or external and in which circuit it is located). Almost zero maintenance, in case of damage, the plug-in module is easily replaceable. The best mode for the development of the devices is based on the manufacture of the metallic modules through a company that produces industrial cabinets; the printed circuit cards, for the electronic part, through a manufacturer of printed electronic cards and finally the assembly of the components in the modules, the card and the necessary electrical wiring, by means of screws and tin solder applied with soldering iron .

Claims (4)

1. CLAIMS.
2. Having sufficiently described my invention, I consider as a novelty and therefore claim as my exclusive property, what is contained in the following clauses: 1 - Metal box containing the components of the base module, consisting of a board of connections for the signals of inputs and outputs, a circular base with 11 terminals for plugging, which serves as an interface to connect the plug-in module claimed in clause 3, and a base of 8 terminals for dry contact relay. 2 - Arrangement of the components in the box of claim 1, to make it operable, when inserting the module of claim 3.
3. 3 - Metal box for plug-in module containing the card with the printed circuit and the electronic components and the connector for plug.
4. 4 - Electrical and electronic circuit contained in the modules of claims 1 and 3 and that together allow the detection of a current of magnitude less than 5 milliamperes, than by electronic components such as resistors, light emitting diodes, optical couplers, capacitors , and transistor, the continuity in an electrical circuit is determined, a logical comparison is made to provide an output signal through contacts activated by a dry contact relay. In testimony of which I sign the month of March of 1996.