Method to ensure electrical safety during routine switching at power facilities
SUBSTANCE: application: in electrical engineering. According to the method during routine switching at power facilities positions of switching devices are indentified, the above positions are transmitted through a radio channel, the Boolean expression is formed for each switching device and power supply is fed to a block lock of the switching device drive at a true value of the Boolean expression. At that data about the position of the functionally related switching devices are accumulated at locations of their drives at local points, data transfer from the local point is made only with a request of the control room, permit for power supply delivery to the block lock is transmitted from the control room through the radio channel, whereat power supply of the block locks is made from in-built self-contained sources.
EFFECT: increasing the operational reliability of the magnetic lock and reducing costs for installation, start-up and commissioning.
The invention relates to methods of providing electrical power plants and substations when carrying out routine switching on the basis of locking actuators switching devices.
The known method electromagnetic lock (1) comprising an automatic alarm from block contacts, a shaft which is pivotally connected through a mechanical element with the drive engaged, the rotation of the rotary element, which causes opening or closing the electric circuit in a switching device, the installation block locks the PA drives the switching devices, the use of a power unit, connected with the contacts and the block-castles in the overall electrical circuit of the cable lines.
The disadvantages of this method electromagnetic lock are:
- the occurrence in the operation of the mismatch position of the rotary element of the switching device to the position of the rotary shaft unit contacts that signal into an electrical block diagram of the position of the switching device, due to the backlash and free moves in the joints of the parts of the drive mechanism and large gaps in the joints of rods;
- unreliable operation because of the large number of moving and fixed block-contacts located on the actuator switching devices�tov and connected by cable lines in General, wiring diagram, especially in outdoor switchgear (ORU), where switching devices are located in the open air;
- the difficulty of maintaining an adequate level of insulation of electrical circuits.
The known method operational lock (2), comprising receiving on cable lines of telemetry signals indicating the position of the switching device, the test, when the need for switching the switching device, a logical arrangement that is implemented in software, and, if according to the logic control is allowed, contact the relay closes and the block lock receives voltage - lock is unlocked. The disadvantages of this method are the complexity of maintaining an adequate level of insulation of electrical circuits as power and telemetry, as well as the emergence in the operation of the mismatch position of the rotary element of the switching device to the position of the rotary shaft unit contacts indicating the position of the switching device.
Closest to the proposed method is a method of electromagnetic lock (3), including the determination of the position of switching devices, transmission on a radio channel situation of the switching device, the formation of the logic circuit block and connect power to the unit to lock the actuator of the switching device when permitted�and from the logic circuit and receiving the radio signal from the block-lock when sticking in it with electromagnetic key.
The disadvantages of this method electromagnetic lock is, first, the continuous transmission of radio signals from the position sensors (two for each switching device). When a certain number of switching devices due to the loaded air in the radio traffic between the sensor and receiver may not function properly. In addition to ensure communication needs continuous power to the transceivers, which puts additional demands on power sources. Secondly, the known method involves external power unit-locks, i.e., the presence of extended supply lines, which may cause a failure of supply due to the insulation of the cord, especially when the ring topology of the power distribution.
The object of the invention is to improve the reliability of operation of the electromagnetic lock and reduce the cost of installation and commissioning by eliminating continuous radio communications between sensors, switching devices and receiving devices, as well as exceptions power lines block locks by using a built-in Autonomous power sources.
This object is achieved in that in the method of providing electrical safety in the production of routine switching at power plants, including the determination of the position of switching devices, per�the country by radio the position of the switching device, the formation of a Boolean expression for each switching device and a power connection unit to lock the actuator of the switching device when the true value of a logical expression, data on the situation of functionally related switching devices accumulate in the locations of their drives in the local points, the data transfer from the local item is performed only upon request from the control center, you can connect power to the unit-the castle passed from the control center via radio, power block locks is carried out by built-in independent sources.
Implementation of data collection on the situation of switching devices directly from the control object allows you to implement the scheme exchange master - slave, where the master performs a control level and local level - driven. This scheme allows sufficient to reduce to a minimum all radiomen, thus significantly reducing the probability of failure of the radio. In addition, this exchange scheme makes it easy to implement the diagnosis of the communication channel, use a multi-exchange principle. Such measures can significantly improve the reliability of functioning of system of locks.
The use of independent power supplies with regular monitoring of their charge allows about�to seem from power lines, this significantly reduces not only the cost of installation and commissioning, but eliminates the probability of failures of power systems due to violations of the wire insulation and, thus, increases the reliability of the whole system.
Fig. 1 shows the block diagram for implementing the method. Marked: l1o, l1Binductive position sensors of the first switching device "off" and "on" respectively; l2O, l2B- lNo, lNB- similarly for other switching devices; 21, 22...2N- block locks drives the first switching device, second etc; 3 - the controller of the switching device 4 - radio transceiver (transceiver controller; 5 - self-contained power source; 6 - radio-frequency transceiver of the control point, 7 - logical device lock; 8 - workstation operating personnel.
The method is implemented as follows. For each switching device according to the operational scheme of the facility is composed of a Boolean expression to enable operations to enable and disable, which are stored in a database hosted in the memory of workstation 8 operational staff. The operands of a logical expression are the position of the respective switching device. Operational staff creates the form p�of clucene workstation 8, which staff member is transmitted to the device 7 logical lock. Device 7 sequentially slip switches retrieves from the database switching devices of a logical expression for the switching device to be off (included). According to the Boolean expression (logical diagram) device 7 requests via the transceivers 4, 6 controller 3 switching devices of the switching units of the logical framework, i.e. on the state of their induction sensors 1. If the logical expression is true, the device 7 permits the controller 3 to connect power to the unit lock 2. Operational staff with solenoid key releases the actuator and carries out switching. The next line in the form of switching is handled similarly, but on the condition that the previous switching device has tripped (on). Power to all nodes of a locking system, in addition to Supervisory level, activates the auxiliary power source 5. The battery level of the source 5 is controlled by periodically polling the device 7 logical lock controller 3, which measures the voltage at the battery source 5.
Sources of information
1. Operating instructions operational safety interlocks in RA�camshaft devices high voltage. Service excellence and information. M: Southeners, 1979, p. 9-38.
2. Operational lock-based KP "Iset". Ekaterinburg: NTK Interface, 2010, pp. 4-7.
3. Description of the invention to the patent of Russian Federation №2274918, IPC CL. NN 9/28, from 22.06.2004.
Method of ensuring electrical safety in the production of routine switching at power plants, including the determination of the position of switching devices, transmission on a radio channel situation of the switching device, forming a Boolean expression for each switching device and a power connection unit to lock the actuator of the switching device when the true value of a logical expression, characterized in that the position information is functionally related switching devices accumulate in the locations of their drives in the local points, the data transfer from the local item is performed only upon request from the control center, you can connect power to the unit-the castle passed from the control center via radio, power block-locks is carried out by built-in independent sources.
SUBSTANCE: switch comprises selector to select winding tap to be reswitched and load switch with at least one tap of current circuit and at least two auxiliary current taps; in each of them in load switch operating both with vacuum circuit breakers and switching cells, besides selector contacts, there are auxiliary switches connected in series with them and the respective winding tap, and in stationary mode the above auxiliary switches perform complete galvanic interruption of vacuum circuit breakers.
EFFECT: providing required dielectric strength to the load switch without increase in dimensions of vacuum circuit breakers.
5 cl, 3 dwg
SUBSTANCE: tap changer with semiconductor switching elements is intended for uninterrupted changing between winding taps of a step transformer; it is made as a hybrid switch comprising fixed mechanical contact fingers and opposed contacts installed at a movable contact bracket. Semiconductor switchover units are intended for load transfer, they are switched by means of contacts at the contact bracket when load is transferred in a specified switching sequence.
EFFECT: development of the tap changer featured by the simple design and high operational reliability, which can be used for switching of different step transformers without forced special-purpose matching to the transformer.
4 cl, 7 dwg
SUBSTANCE: invention relates to the method of detecting of malfunction of the vacuum breaker in a live tap changer in which the tap changer contains a housing filled with oil, a diverter switch comprising a mobile contact (MC, RC) and, at least, one vacuum breaker (MVI, RVI) designed with a possibility of interruption of the current passing through the mobile contact of the diverter switch. The method includes the repeating stages during which the content of hydrogen in oil is determined and the existence of malfunction of the vacuum breaker (MVI, RVI) is identified on the basis of measurement of the content of hydrogen in oil.
EFFECT: decrease of risk of false identification of malfunction with an immediate emergency shutdown of the transformer.
11 cl, 9 dwg
FIELD: machine building.
SUBSTANCE: invention refers to a drive mechanism. A drive mechanism for a medium voltage fuse switch comprises a base plate (10) and a front plate (11) which form an inner space enveloping a working shaft and a driving shaft set coaxially along the first longitudinal axis, the driving shaft is functionally coupled with a kinematic circuit of the medium voltage fuse switch, the working shaft (20) is fitted by a head connected to an operating handle for manual actuation of the working shaft, a spring unit consisting of two spiral springs having the first end functionally coupled with the working shaft, a clamping unit consisting of two clamping tabs set on the driving shaft, the first (61) and the second (62) unclamping units to unclamp the driving shaft and provide for its rotation. The first unclamping unit (61) provides for the rotation of the driving shaft in the direction opposite to the second unclamping unit (62).
EFFECT: reduced manufacturing, mounting and operational costs.
11 cl, 8 dwg
SUBSTANCE: invention is related to an on-load tap charger with semiconductor switching elements for uninterrupted switching between fixed contacts of the tap charger which are connected electrically to the tapped winding of the tapped transformer. Each of the fixed contacts of the tap charger can be connected to the device for charging either directly or through interconnected semiconductor switching elements. According to the invention the tap charger has separated and fixed tapping contacts for electric insulation of the semiconductor switching elements from the transformer winding during the static mode of operation.
EFFECT: excluding high load of switching elements and guaranteeing electrical separation of the tap charger from the transformer winding in the static mode of operation.
9 cl, 3 dwg
SUBSTANCE: tap changer for a transformer comprises a cylinder and a shaft which is rotatably arranged inside the cylinder. The cylinder is provided with fixed contacts and the shaft is provided with a contact circuit facing the cylinder and including mechanical contacts, wherein the mechanical contacts are adapted to selectively mate with the fixed contacts of the cylinder upon rotation of the shaft. The contact circuit also includes at least two measuring points for measuring the characteristics of the contact circuit. The tap changer comprises at least one measuring contact device, which is electrically connected to the respective measuring points in the contact circuit. The measuring contact device is placed inside the shaft.
EFFECT: wider field of use of the tap changer and the measurement method by facilitating access to measuring points of the tap changer.
14 cl, 8 dwg
SUBSTANCE: invention relates to a manual drive for stepwise control of a step transformer winding tap changer with a locking device, without power consumption. Besides, there is a master shaft, on which per one change there are several manual rotations implemented. There is also a control mechanism, which converts these rotations exactly into one rotation of a geared wheel per one change. The locking mechanism comprises a rotary inner key and a latch rotating around the axis of rotation and a stop, which corresponds to the stop slot of the master shaft, and a stop cam, which corresponds to the slot of the geared wheel of the control mechanism. Due to actuation of the inner key, the latch rotates from the locked position so that the stop and the stop cam are disengaged from the appropriate slots.
EFFECT: higher reliability of protection in respect to undeliberate or deliberate incorrect usage of a manual drive.
7 cl, 10 dwg
SUBSTANCE: invention is designed for changing taps in power transformers. A modified diverter switch comprises mechanical and electric interface, compatible with a switch body, main and intermediate contacts, a holder of current-limiting resistance comprising an interface coupled with the body of the available tap changer for provision of modification of the diverter switch, besides, multiple modules of current-limiting resistances may be connected together. The diverter switch may comprise a vacuum switch and may be installed in a body of the available tap changer.
EFFECT: invention provides for simple tuning of a diverter switch to user requirements for various use and possibility to modify an on-load tap changer.
6 cl, 10 dwg
SUBSTANCE: in several horizontal planes around rotating switching axis on insulating frame, fixed contacts are located. These contacts contain upper and lower contact fingers which are released and closed by electroconductive bus as moving switching contact.
EFFECT: design simplification, functionality enhancement and increase in durability.
9 cl, 8 dwg
SUBSTANCE: compartment (2) of the electric motor within the on-load tap changer comprises an electric motor module and a control module (12). The module of the electric motor comprises an electric motor (6), a reducer (7) and a position sensor (9), besides, the control module (12) is made with the possibility to control an output shaft (3), which goes out from the compartment (2) of the electric motor, by means of power supply to the electric motor (6) via a direct connection to put the output shaft (3) in motion via a reducer (7), besides, the position sensor (9) is made with the possibility to register motion and positions of the output shaft (3) and to transfer information about such to the control module (12). The compartment (2) of the electric motor in the working condition is tightly closed with the electric motor module and the control module (12), arranged inside such tightly closed volume.
EFFECT: reduced time for production deployment, increased flexibility for making changes into the order at the later stages of its completion, increased convenience of service, reduced cost of the electric motor for the on-load tap changer.
7 cl, 2 dwg
FIELD: electrical engineering.
SUBSTANCE: proposed mechanical switching contact designed for double-pole change-over has holder made of insulating material that accommodates fixed contacts alternately coming in contact with contact holder; the latter, in its turn, mounts on its loose end turning lever carrying on its end respective conducting contact member. Mechanical switching contact is made in the form of modular structural unit that can be arbitrarily assembled. It has minimal quantity of structural components for double-pole switching and can be easily built in load switch without additional adjustment and matching.
EFFECT: simplified design, reduced space requirement.
4 cl, 4 dwg
FIELD: electrical engineering.
SUBSTANCE: step switch comprises accurate selector of transformer winding taps and if required preliminary selector designed for selection winding tap for switch without power consumption, as well as power switch of winding taps. At least one three-phased torque drive is provided in connection with transmission devices of various performances. Torque drive functions in different ways for certain structural assemblies.
EFFECT: design simplification due to reduction of part count, advanced compactness, high operation dynamics enabling stick-slip motion and improved performance.
16 cl, 20 dwg
SUBSTANCE: device contains two electric branches, some ends of which are connected between each other, and the others - to corresponding contacts of plug. Every branch includes indicator element, which is serially connected to limiting resistor. Indicator elements are arranged in the form of light diodes that are connected back-to-back. Earthing contact is taken out from the middle point of electric circuit that connects both branches.
EFFECT: simplification of device; higher reliability.
SUBSTANCE: invention relates to shunt resistance circuit breaker with control element and electrical circuit. The electrical circuit includes the main branch line (1) and resistible branch line (2) being connected in parallel with the main branch line (1). Each branch line contains contact (11, 21) and vacuum circuit breaker (12, 22). Resistible branch line (2) includes also a resistor (30). The main contact of rotary selector is always actuated before resistible contact (21). In accordance with the invention the control element is implemented so that it turns the main contact (11) in the same rotational direction during controlling operations. The invention also considers the related control method for shunt resistance circuit breaker and use of the circuit breaker.
EFFECT: provision of simple control function ensuring main contact actuation before resistible contact.
28 cl, 14 dwg
SUBSTANCE: tap switch (10, 20) designed for electric transformers includes drive mechanism and frame containing at least two elongated pins (11) to which there attached is a number of fixed male contacts located perpendicular in a row thus forming a whole entity. Besides switch consists of a system of moving contacts (14) operating based on friction, which slide along fixed contacts (12) owing to impact of worm (23). In end part of insulating tube (27) a nut thread is made or attached coaxially to worm (23) and outside it so that system of moving contacts (14) is fixed by means of shaped holder (28) in end part of insulating tube (27) opposite nut thread. Thus, nut thread is located in position different from the position of system of moving contacts (14) in relation to total length of switch (10, 20), thus providing use of moving contacts (14) without restrictions of sizes of tube (27) and/or worm (23).
EFFECT: simplifying the design, increasing functionality, reliability and strength, and improving manufacturability.
7 cl, 3 dwg
FIELD: electric engineering.
SUBSTANCE: switch is closed on top with head that comprises head flange, in which driving shaft leading outside is installed. At this head flange there might be an available upper transmission step is arranged, or by means of compatible flange, a flywheel drive is installed without necessity in additional various units, in particular special head of switch.
EFFECT: provision of possibility to implement actuation of insulated switching shaft only with one head of switch, independently on type of drive.
2 cl, 4 dwg
FIELD: electrical engineering.
SUBSTANCE: invention relates to power accumulator for step switch operated at load with lengthwise-travel winding slides and lengthwise-travel jumping slides which, when unlocked, repeat the motion of winding slides and convert their translation into rotation of output shaft that actuates loaded step switch. Said jumping slides accommodate two guided rollers arranged in particular-geometry link. Note here that during first part of every stroke of jumping slides only one roller in guided in said link with geometrical tangenting (jointing), while, during second part of stroke, second roller moving free is guided in said link with geometric tangenting, while roller guided previously in said link moves free. Finally, during third part of stroke, roller moves again with geometrical tangenting in said link.
EFFECT: possibility to vary torque at output shaft and to produce high torque that allows reliable reach of final position and repeated interlocking of power accumulator.
5 cl, 4 dwg
SUBSTANCE: invention relates to mechanical switching contact with insulating holder (1), where fixed contacts (4, 5, 6) are arranged. Besides lever (2) with rotary lever (22) is installed on insulating holder (1) with the possibility of rotation. Additionally another rotary body (3) of contact is installed on insulating substrate (1) with parallel contact fingers (9, 10), which accordingly embrace connected fixed contacts (4, 5, 6) on both sides.
EFFECT: invention provides for reliable switching at high currents, and switching with absence of vibrations and electric arc.
3 cl, 8 dwg
SUBSTANCE: device for transmission of rotational movement includes movement conversion unit that includes intermediate element (3) connected with rotation axis (3a) with the possibility of rotating round it, mechanical energy accumulating unit (5) in a form of spring device, unit of stretchable/compressible spring connected with solid clamp and movable clamp and means of transmitting mechanical energy accumulated in spring device to driven element (2) via drive shaft (2a). Note that intermediate element (3) contains cam drive roller interacting with energy accumulating unit (5). Movable clamp is equipped with rolling element that contacts with drive roller periphery. Movable clamp can be performed with the possibility of moving in radial direction parallel to plane of drive roller. Method of transmission of rotational movement to element includes transmission of mechanical energy accumulated in spring device to drive shaft. Application of proposed device for rotational movement transmission is performed with the possibility of winding switch contacts' control under load in transformer or stabiliser.
EFFECT: improvement of rotational movement transmission use.
15 cl, 6 dwg
SUBSTANCE: high-voltage semiconducting switching device consists of selected by leakage current series connected unpackaged semiconducting elements that are centred and isolated by side surface with the help of fluoroplastic rings, housing, clamping system and current-carrying electrodes. The housing is made of isolating material with high mechanical and electrical strength. At both housing ends there are rigidly fixed metal flanges that are included in clamping system with threaded holes. At bolting of switching device cover to housing flanges with the help of clamping system elements located inside the cover there created is necessary compressive force of semiconducting devices and its transmission through the housing to semiconducting devices. Note that at the same time there performed is pressurisation of inner volume of switching unit housing by O-rings located between flanges and current-carrying electrodes.
EFFECT: increase of specific switching power of high-voltage semiconducting switching device current at simultaneous improvement of its switching characteristics.
5 cl, 1 dwg