RU2729200C1 - Combined glaze ice melting system and load curve smoothing using energy accumulators based on storage batteries and high-power supercapacitors contained in autonomous power plant assembly - Google Patents

Abstract

FIELD: electric power engineering.SUBSTANCE: plant comprises a three-phase bridge converter on fully controlled semiconductor gates, shunted by mutually connected diodes, first three-pole switch and series-connected three-phase throttle, in parallel to first three-pole circuit breaker connected alternating current generator with series-connected second three-pole switch for load supply, n units of storage batteries and/or high-power supercapacitors (hereinafter - units) have the possibility of parallel and serial connection to a group of accumulators, first double-pole switch by contacts connects a group of accumulators with emitter and commutator outputs of converter valves, parallel connection of units to group of accumulators is carried out using n double-pole switches, serial connection of units to group of accumulators is carried out using n single-pole switches, one output of group of accumulators is connected by means of first contact of third three-pole switch with wire of overhead line, second output of group of accumulators is connected by means of second contact of three-pole switch with first output of converter, third contact of three-pole switch closes ground with second output of converter. In the first case, the units used to smooth load graphs are closed by the first switch open in the second case and closed by the remaining n double-pole circuit breakers forming a group of accumulators consisting of parallel connected units, open in the second case. In the second case, which is intended for glaze ice melting, group of accumulators is closed by the third three-pole switch, open in the first case, and closed by n single-pole switches, which form series connection of blocks, open in the first case, one output of the group of accumulators is connected "plus" to the wire of the overhead line, and the second output of the group of accumulators "minus" with the first output of the converter, where the second output of the converter is connected to ground, at that melting ice with direct current is carried out according to the circuit "wire - ground".EFFECT: possibility of melting glaze ice over long distances by means of high-power energy accumulators contained in gas piston units in autonomous power supply systems on overhead lines with voltage 0_4 kV, 6–10 kV, that is without purchase of additional equipment.1 cl, 1 dwg

Description

The invention relates to the field of electrical engineering and can be used in autonomous power supply systems already equipped with energy storage units (NE), which are equipped with gas piston plants (GPU), and requiring smoothing the load schedule and melting ice on overhead power lines.

- Slovak Republic. - 2019, pp. 488-493.). Применение НЭ в комплекте с ГПУ позволяют предотвратить провалы частоты переменного тока при возмущающих воздействиях нагрузки, обеспечить поддержание требуемого уровня остаточного напряжения при коротких замыканиях в сети (см. Bakhteev K., Fedotov A. and Misbakhov R. The Improving quality of power supply to industrial consumers using high-power energy storage / 2018 IEEE 59th International Scientific Conference on Power and Electrical Engineering of Riga Technical University (RTUCON), Riga, Latvia, 2018, pp. 1-5.), выравнять график нагрузки, снизить потери энергии в электросетях (см. Брагин А.А. Алгоритм формирования графиков электрических нагрузок предприятия с применением аккумуляторных батарей в качестве потребителей-регуляторов мощности / Диссертация канд.тех.наук. - СПб. - 2013.). Разработка подхода к рациональному использованию НЭ с учетом исходного переменного графика нагрузки позволит существенно снизить не только затраты на потребление электроэнергии предприятием, но и затраты при ее производстве.Unlike large power systems, autonomous power systems located in remote areas have a significantly lower regulation potential due to changes in the power of generating facilities and intersystem flows. Isolated power systems are characterized by a very limited number of generating facilities and consumer groups. GPUs are increasingly used as an autonomous source of main and backup power supply. In the course of research, it was determined that it is most rational to use electrochemical storage devices in autonomous systems for GPUs running on associated gas to reduce the cost of purchasing fuel, since it is energy storage devices (EEs) that ensure the operability of installations under load surges (see Bakhteev K., Fedotov A. , Chernova N., Misbakhov R. Methodological Approaches to the Choice of Energy Storage and Optimization of Their Parameters to Improve the Electric Power Quality in Various Types of Electric Power Systems / Proceedings of the 10th International Scientific Symposium on Electrical Power Engineering ELEKTROENERGETIKA 2019. -

- Slovak Republic. - 2019, pp. 488-493.). The use of NEs in a set with a GPU allows to prevent AC frequency dips during disturbing load influences, to ensure the maintenance of the required level of residual voltage during short circuits in the network (see Bakhteev K., Fedotov A. and Misbakhov R. The Improving quality of power supply to industrial consumers using high-power energy storage / 2018 IEEE 59th International Scientific Conference on Power and Electrical Engineering of Riga Technical University (RTUCON), Riga, Latvia, 2018, pp. 1-5.), equalize the load schedule, reduce energy losses in power grids (see Bragin A.A.Algorithm for the formation of graphs of electrical loads of the enterprise with the use of batteries as consumers-power regulators / Dissertation of Candidate of Technical Sciences - SPb. - 2013.). The development of an approach to the rational use of electric power, taking into account the initial variable load schedule, will significantly reduce not only the costs of electricity consumption by the enterprise, but also the costs of its production.

Another important technical problem aimed at improving the reliability of power supply to consumers is the melting of ice on overhead power lines, which allows you to prevent dangerous mechanical overload and eliminate the dance of wires. Both alternating and direct current can be used to heat the wires. The use of alternating current does not require significant costs, since melting is carried out directly from the existing network, and is possible only at relatively short lengths of heated lines, the required melting currents and voltages. For lines with wires of considerable length, direct current melting is advantageous. For direct current melting, a variety of converters are used, also made on semiconductor power key elements. However, they are used for their intended purpose for a relatively short time and only during periods of ice formation. In this regard, it is advisable to combine the functions of smoothing the load curves and melting ice in one device, high-power NEs, which are part of an autonomous power plant, in order to save capital costs due to a reduction in the total volume of separately installed equipment.

Known combined installations for compensating reactive power and melting ice, made on the basis of a three-phase bridge converter (two or three-level) on fully controlled power semiconductor devices - IGBT or lockable thyristors (see RF Patent No. 2505903 dated January 27, 2014).

The disadvantage of this installation is that ice melting is carried out over short distances.

The objective of the invention is to develop a combined system for melting ice and smoothing load curves using energy storage devices based on storage batteries and high-power supercapacitors, which are part of an autonomous power plant, where the disadvantages of the prototype are eliminated.

The technical result is the ability to melt ice over long distances using high-power NEs, which are part of the GPU in autonomous power supply systems on overhead lines with a voltage of 0.4 kV, 6-10 kV, i.e. without buying additional equipment.

The technical result is achieved by the fact that a combined system for melting ice and smoothing load curves using energy storage devices based on storage batteries and high-power supercapacitors, which are part of an autonomous power plant, containing a three-phase bridge converter on fully controllable semiconductor valves shunted by oppositely connected diodes, the first three-pole a circuit breaker and a series-connected three-phase choke, an alternator is connected in parallel to the first three-pole switch, with a second three-pole switch connected in series to power the load, n-blocks of storage batteries and / or high-power supercapacitors (hereinafter referred to as blocks) have the possibility of parallel and series connection in a group drives, the first two-pole switch with contacts connects a group of drives with the emitter and collector terminals of the converter valves, in parallel blocks are connected to the storage group using n-two-pole switches, the series connection of blocks to the storage group is carried out using n-single-pole switches, one output of the storage group is connected through the first contact of the third three-pole switch with an overhead line wire, the second output of the storage group is connected through the second contact of the three-pole switch with the first output of the converter, the third contact of the three-pole switch closes the ground with the second output of the converter, in the first case, the blocks used to smooth out the load curves are closed by the first switch, opened in the second case, and closed by the remaining n-two-pole switches that form a group of storage units, consisting of parallel-connected blocks, open in the second case, which is intended for melting ice, the storage group is closed by the third three-pole switch, open in the first case and closed n - single-pole switches that form a series connection of blocks, open in the first case, one output of the storage group is connected by "plus" to the overhead line wire, and the second output of the storage group is connected by "minus" to the first output of the converter, where the second output of the converter is connected to ground, when In this case, the melting of ice with direct current is carried out according to the "wire-ground" scheme.

The daily load schedule of the electrical complex of the enterprise has a great influence on energy efficiency, in the case of its equalization, the specific fuel consumption for electricity generation decreases, the blocks in normal mode are designed to accumulate electricity from the network during a period of low demand and return it to the network or to the load during a high demand, and when melting ice, the blocks are connected in series to the storage group to increase the voltage supplied to the wire and operate according to the ice melting scheme using the "wire-ground" working ground.

The drawing shows a diagram of a combined system for melting ice and smoothing load curves using NE based on storage batteries and high-power supercapacitors, which are part of an autonomous power plant.

The numbers in the drawing indicate:

1-3 - series-connected fully controlled semiconductor switches - IGBT-transistors, shunted by counter-connected diodes;

4 - alternator;

5 - the first three-pole switch;

6 - three-phase choke;

7 - two-pole switch;

8 - blocks of storage batteries or high-power supercapacitors with the possibility of parallel or serial connection to the storage group;

8.1.1-8.1.N - blocks of storage batteries or high-power supercapacitors from 1 to N;

8.2.1-8.2.N - single-pole switches used for serial connection of blocks;

8.3.1-8.3.N - double-pole switches used for parallel connection of blocks;

9 - the second three-pole switch;

10 - diagram of melting ice "wire-ground";

11 - the third three-pole switch.

The proposed combined installation for smoothing load curves and melting ice is made on the basis of a bridge converter containing three arms 1-3 on series-connected fully controlled semiconductor switches - IGBT transistors, shunted by oppositely connected diodes. On the alternating current side, an alternator 4 is connected with a series-connected three-pole switch 11 to supply the load, and a three-phase choke 6 is connected in parallel to the generator through a three-pole switch 5. A battery pack and high-power supercapacitors 8 are connected to the converter's DC output.

According to the first installation option in the mode of smoothing the load curves, the blocks of storage batteries and supercapacitors 8.1.1-8.1.N are connected by the contacts of the first two-pole switch 7, with the emitter (collector) terminals of the converter valves, open in the mode of melting ice, the blocks of storage batteries and supercapacitors are connected in parallel two-pole switches 8.3.1-8.3.N into the storage group, open in the ice melting mode.

According to the second option, in the ice melting mode, the accumulator batteries and supercapacitors units 8.1.1-8.1.N are connected in series with single-pole switches 8.2.1-8.2.N to increase the voltage supplied to the wire, open in the mode of smoothing the load curves, one output of the storage group 8 " plus "is connected by means of the first contact of the second three-pole switch 9 with the overhead line wire, the second output of the storage group is connected by the second contact of the three-pole switch with the first output of the converter, the third contact of the three-pole switch closes the ground with the second output of the converter, the three-pole switch is open in smoothing mode load graphs, while melting ice with direct current is carried out according to the "wire-ground" scheme.

The installation works as follows:

In the mode of smoothing the load curves, the generator 4 operates on the load, the switch 11 is in the closed state, and the battery units 8 work to maintain a uniform load curve, they are connected by the first two-pole switch 7. The units are connected in parallel by the two-pole switches 8.31-8.3.N with emitter and collector terminals valves of reversible AC / DC converters, consisting of modules on IGBT transistors 1-3, through a three-pole switch 5 and a three-phase choke 6, which is used as an output filter for a given voltage ripple factor, a group of storage devices give the stored energy to the network. Fuel economy in the electrical complex can be ensured if the load schedule is significantly uneven. Then, during the hours of minimum load, the energy storage units 8 are charged, and during the hours of maximum load they give their energy to the network. The development of an approach to the rational use of energy storage units, taking into account the initial variable load schedule, will significantly reduce not only the costs of electricity consumption by the enterprise, but also the costs of its production. The development of an approach to the rational use of energy storage units, taking into account the initial variable load schedule, will significantly reduce not only the costs of electricity consumption by the enterprise, but also the costs of its production.

In the ice melting mode, the alternator 4 is disconnected from the load using switch 11 and starts to work on ice melting, two-pole switch 7 and two-pole switches 8.3.1-8.3.N open, three-pole switch 9 and single-pole switches 8.2.1-8.2.N are closed, forming a series connection of blocks, thereby increasing the voltage supplied to the wire and ice begins to melt according to the wire-to-ground scheme 10, where the ground is used as a return wire. Therefore, direct current melting of wires of high-voltage lines using land is beneficial both from a technical point of view (the possibility of melting high-voltage lines with a length of 100 km or more), and from an economic point of view (reducing the melting time and the number of melting cycles).

Claims (1)

Combined system of ice melting and smoothing of load curves using energy storage devices based on storage batteries and high-power supercapacitors, which are part of an autonomous power plant, containing a three-phase bridge converter on fully controlled semiconductor valves shunted by counter-connected diodes, the first three-pole switch and a three-phase choke connected in series , characterized in that an alternator with a second three-pole switch connected in series to power the load is connected in parallel to the first three-pole switch, n battery packs and / or high-power supercapacitors (hereinafter referred to as blocks) have the possibility of parallel and serial connection to a group of storage devices, the first two-pole the switch with contacts connects the storage group with the emitter and collector outputs of the converter valves, the parallel connection of the blocks in the group storage devices are carried out using n double-pole switches, the series connection of blocks into a storage group is carried out using n single-pole switches, one output of the storage group is connected through the first contact of the third three-pole switch with an overhead line wire, the second output of the storage group is connected through the second contact of the three-pole switch with the first output converter, the third contact of the three-pole switch closes the ground with the second output of the converter, in the first case, the blocks used to smooth out the load curves are closed by the first switch, opened in the second case, and closed by the remaining n two-pole switches, forming a group of storage units consisting of parallel-connected blocks, open in the second case, which is intended for melting ice, the storage group is closed by the third three-pole switch, open in the first case, and closed by n single-pole switches by the devices forming a series connection of the blocks, which are open in the first case, one output of the storage group is connected by a "plus" to the overhead line wire, and the second output of the storage group is connected by a "minus" to the first output of the converter, where the second output of the converter is connected to the ground, while melting ice direct current is carried out according to the "wire-ground" scheme.

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