Complex diagnostic of all types of high-voltage circuit breakers. New PKV/M17 instrument

SKB (Special Design Bureau) of Electric Instrument Engineering LLC (SKB EP) has been developing and manufacturing diagnostic equipment for monitoring the technical condition of high-voltage circuit breakers and transformers for more than 26 years. The line of equipment produced today for diagnostics of high-voltage circuit breakers is well-known in the instrumentation and control market. It consists of three instruments: PKV/M7, PKV/U3.1 and PKV/U3.0 for measuring speed and time parameters of high-voltage circuit breakers, as well as recording the cross-arm movement charts. In addition, due to the use of advanced technologies, our instruments can be used for circuit breakers made in the Soviet Union, Russia, and foreign countries, regardless of their type and voltage class.

Despite the fact that these instruments cover a fairly large number of needs of power engineering specialists, the energy industry is actively developing and increasing requirements to the diagnostic equipment, thus providing a basis for building new measurement systems. SKB EP specialists are actively working in this direction, constantly upgrading and improving the existing range of devices, so a new instrument for monitoring high-voltage circuit breakers, PKV/M17, is planned for release in the next year.

PKV/M17 is designed for comprehensive diagnostics of oil, vacuum, SF6 and air circuit breakers with a voltage from 6 to 750 kV made in the Soviet Union, Russia, and foreign countries (ABB, ALSTOM, AREVA, SIEMENS, etc.) in accordance with the requirements of RD 34.45-51.300-97 and manufacturers' instructions.

In comparison with its predecessors, the PKV/M17 boasts even more extended measurement ranges of time intervals (up to 200 s), speed (up to 50 m/s) and travel (up to 900 mm), which cover the monitoring needs for all existing circuit breakers. In addition, the device has a number of very significant and distinctive features:

Measurement of speed and travel parameters on 3 poles at the same time (simultaneous connection of 3 travel transducers is possible). This is due to the fact that when performing measurements with a single movement transducer, the travel parameters for each phase have to be measured by moving it from one phase to another. At the same time, three CO (Close-Open) operations are required. However, if you use three transducers at the same time, such a measurement can be performed faster, since only one CO operation is required.

The device is supplied with incremental (discrete) transducers, DP12 (linear) and DP21 (angular), which do not require tweaking or adjustment of conversion factor and are characterized by accuracy and ease of operation. In addition, the device supports other set of movement transducers: rheostat and laser triangulation types.

Measurement of the time performance of high-voltage circuit breakers simultaneously on 3 poles with up to 2 breaks per pole or on 1 pole with up to 6 breaks.

Recording of switching time for contacts with per-insertion resistors (PIR). This type of monitoring is necessary because these contacts are used to reduce voltage surges and prevent insulation damage that occurs due to a transient process, for example, when opening a high-voltage circuit breaker on a long line.

Measurement of electric current using built-in current sensors or external clamp meters to assess the condition of the drive of a high-voltage circuit breaker, control current circuits, etc. In addition, compared with previous models, the number of clamp meter channels in PKV/M17 is increased (4 pcs.) for measurements on circuit breakers with separate drives.

Configuring simple (O, C) and complex cycles (OC, CO, OCO, OCO-C, OCO-CO) for switches with a maximum current of up to 35A for DC or AC drives thanks to the built-in control panel (switch).

Control of vacuum circuit breakers (BB/TEL, etc.) became possible due to the fact that the built-in switch of the instrument was modified. Now it can work either in the mode of supplying voltage to the CLOSE/OPEN electromagnets or as a dry contact to control the BB/TEL circuit breakers.

PKV/M17 has a built-in microohmmeter for measuring the contact resistance in high-voltage circuit breakers in the range of 1 μΩ to 0.1 Ω at a current of 10A, which is sufficient for evaluative rapid diagnostic. In addition, the measurement is carried out on the pole cables, which eliminates additional equipment, and also reduces the number of ascents/descents to the circuit breaker for reconnecting the clips of the test cables.

For the first time among Russian-made devices, PKV/M17 can test a high-voltage circuit breaker in the "First trip" mode. This mode allows you to perform a rapid analysis of the circuit breaker condition when high voltage is removed. In addition, "First trip" makes it possible to determine the actual characteristics of the equipment after its long stay in the closed position.

It is often necessary to check the circuit breakers by closing them not by the drive, but, for example, using a jack. To do this, the PKV/M17 instrument provides a "Ruler/ Protractor/Multimeter" mode that facilitates the adjustment of the circuit breaker. The device displays the value of the circuit breaker travel (or the angle of shaft rotation) and the state of the contacts (closed/open) in real time.

In addition to innovations, PKV/M17 has retained all the best characteristics and parameters tested and approved by experts, including automatic calculations of technical parameters of high-voltage circuit breakers (time difference, chatter duration, delay duration, rebound, overshoot, average speeds on various travel sections, etc.) and a unique method of analyzing charts, which allows early detection of defects in the mechanisms of high-voltage circuit breakers.

According to the developed method, incipient or existing faults of a high-voltage circuit breaker (increased backlash, spring weakening, increased friction, damper failure, etc.) have characteristic traits and features on the charts, which can be used to unambiguously determine the state of its elements. Even minimal experience in interpretation of charts allows you to identify the circuit breaker components that require intervention of repair personnel before the repair begins, and avoid subjecting the healthy mechanisms to unnecessary (and often harmful) disassembly, thereby reducing the repair time and saving money of the company. Moreover, working with charts will become even easier and more convenient thanks to a large (7”) high-brightness color touch screen.

The method of diagnosing hidden defects of circuit breakers has repeatedly received positive feedback from such companies as FGC UES PJSC, Rosseti PJSC, ROSATOM State Corporation, Oboronenergo OJSC, ZETO LLC, Elektroapparat OJSC IBC, Vostoknefteprovod LLC, Russian Railways OJSC, Hydroelectromontazh OJSC, UETM JSC and many others.

In addition, the integrated approach to the monitored parameters of high-voltage circuit breakers implemented in PKV/M17 will reduce the time for monitoring circuit breakers, as well as identify faults at an early stage through the analysis of digital data and movement charts, thereby significantly extending the service life of switching equipment.

PKV/M17 is able to meet almost any requirements that arise during operation, as well as at the stage of production and testing of new high-voltage switching equipment. At the moment, the device is undergoing testing and trial operation for adding it to the State Register of Measuring Equipment.

If you are interested in PKV/M17 or you want to learn more about other PKV instruments for monitoring high-voltage circuit breakers, please contact our managers by phone +7 (812) 500-25-48 or by e-mail skb@skbep.com Official website of the company: www.skbep.com

The manufacturer reserves the right to make changes to the specifications of the manufactured equipment without prior notice to the buyer. Please check with our managers before placing your order.