CN106300204A - A kind of HVAC power transmission line conductor ice prevention device and combinations thereof - Google Patents

Abstract

The invention discloses an anti-icing device for wires of a high-voltage AC transmission line, which comprises an ice-melting device and a high-pass filter. Install an ice-melting device at one end A of the high-voltage transmission line that needs to be deiced, and install a grounded second high-pass filter at the other end B; the ice-melting device includes an inductor L1, a capacitor C, a capacitor C2, a high-frequency power module, a high-frequency High-frequency transformer T and the first high-pass filter; the high-frequency power module is connected to the high-voltage AC transmission line through the high-frequency transformer T and capacitor C in turn, one end of the inductor L1 is connected to the capacitor C and capacitor C2, and the other end is connected to the grounded first high-pass filter device. The invention realizes non-stop anti-icing of high-voltage AC transmission line conductors, avoiding economic losses caused by power outages; the ice-melting device and the high-pass filter are installed in the substation, and the ice-melting device does not need to be installed at the midpoint of the deicing line with harsh environments, which is very convenient The installation and maintenance costs are greatly reduced, and the reliability and stability are significantly improved.

Description

An anti-icing device for wires of high-voltage AC transmission lines and its combination

technical field

The invention relates to the field of power systems, and relates to a high-voltage AC power line anti-icing technology. Specifically, it relates to an anti-icing device for wires of a high-voltage AC transmission line and a combination thereof.

Background technique

In the rainy and snowy weather in winter, continuous low-temperature rain and snow freezing will cause winter icing of transmission lines. The icing of high-voltage transmission lines in the field is likely to cause various mechanical accidents and electrical accidents. Therefore, how to prevent the icing of high-voltage transmission lines in the field is a major problem in the power system. The mainstream thermal deicing method increases the current or current density in the transmission line, or increases the equivalent resistance of the transmission wire, or increases the current and resistance of the wire at the same time, so that the transmission wire itself heats up, thereby melting the ice on the wire. It mainly includes short-circuit current deicing, high-frequency excitation deicing, DC current deicing, and power flow dispatching deicing. Among them, short-circuit current deicing, DC current deicing, and power flow dispatching deicing require power outages for 4-8 hours per time when deicing transmission lines, which has a great negative impact on the power supply quality and economic benefits of the power system.

The online high-frequency deicing and anti-icing method based on the skin effect can realize online (non-power-off) anti-icing and anti-icing. When high-frequency and high-voltage excitation is applied to the ice-coated wire, it can make the ice become a lossy dielectric and generate heat directly, and it can also cause the skin effect of the wire, so that the current only flows on the surface of the conductor, resulting in greater equivalent resistance loss and heat generation , so as to use the heat generated by the two to de-ice. The existing high-frequency deicing and anti-icing method can only install a high-frequency high-voltage excitation device (high-frequency power supply) at the midpoint of the deicing line, and install a trap filter (high-pass filter) at both ends of the line to control the high-frequency The scope of the frequency current. However, most of the midpoints of the deicing lines are located in remote areas with harsh environments such as forests, mountains, and lakes. The construction cost is very high, and the staff need to travel long distances to enter the station for operation and maintenance. The labor intensity is high, and it may even cause casualties. ; When the midpoint of the line is a lake, etc., the geographical location of the midpoint of the line cannot build a high-frequency power supply.

In addition, the core component of high-frequency power supply - high-frequency inverter switch components are mostly composed of IGBT, MOSFET and other semiconductor power devices connected in series and parallel. These semiconductor switches are expensive, the construction cost of the device is very high, and the cost performance of equipment operation is very low. The above analysis shows that the existing high-frequency deicing and anti-icing methods do not have good engineering application prospects. How to overcome the above problems is a research direction for those skilled in the art.

Contents of the invention

Aiming at the remote installation location of the existing high-frequency deicing and anti-icing devices, the construction and maintenance costs are very high, the labor intensity of the operators is high, the response time period is long, and it may even cause life-threatening problems. The present invention proposes a novel high-frequency power supply anti-icing device based on a semiconductor power device-a reverse switching transistor (Reservely Switched Dynistor, RSD), to solve the above problems.

In order to achieve the purpose of the present invention, technical scheme is as follows:

An anti-icing device for wires of high-voltage AC transmission lines, including an ice-melting device and a high-pass filter; the two endpoints of a single AC wire of the AC transmission line that needs to be deiced are A terminal and B terminal respectively, which are called ice melting Section AB; the end point A of the ice-melting section AB that needs to be deiced is equipped with an ice-melting device, and the end point B of the other end is connected to a grounded second high-pass filter; the ice-melting device includes an inductor L1, a capacitor C, a capacitor C2, Isolating switch K, isolating switch K4, isolating switch K5, isolating switch K6, high-frequency power supply, capacitor C3, high-frequency transformer T and the first high-pass filter; the high-frequency power supply passes through the high-frequency transformer T, capacitor C, isolation The switch K and the capacitor C2 are connected to the input point of the A terminal of the ice-melting section AB, one end of the capacitor C2 is connected to one end of the isolation switch K, and the other end of the capacitor C2 is connected to the input point of the A terminal of the ice-melting section AB; One end of the inductance L1 is connected to the common end of the isolating switch K and the capacitor C2, the other end of the inductance L1 is connected to the common end of the isolating switch K4 and the capacitor C3, and one end of the capacitor C3 is connected to the common end of the isolating switch K4 and the inductance L1. The other end of the capacitor C3 is connected to the A-end output point of the ice-melting section AB, one end of the isolating switch K4 is connected to one end of the capacitor C3, and the other end of the isolating switch K4 is connected to one end of the first high-pass filter. The other end of the high-pass filter is grounded; one end of the isolating switch K5 is connected to the common end of the isolating switch K and the capacitor C2, and the other end is connected to the A-end output point of the ice-melting section AB; one end of the second high-pass filter is connected to the isolation One end of the switch K6, the other end of the second high-pass filter is grounded, and the other end of the isolating switch K6 is connected to the B end of the ice-melting section AB.

By adopting this technical scheme: the high-frequency power supply is connected to the high-voltage AC transmission line through the high-frequency transformer T and the resonant capacitor C in sequence, and the high-frequency current is superimposed on the power frequency current to make the effective deicing and anti-icing current of the line wire Reach or exceed the minimum de-icing and anti-icing current, realize the anti-icing of the wires of the high-voltage transmission line, realize non-stop anti-icing, and reduce the economic loss caused by power failure.

Preferably, in the anti-icing device for the wires of the high-voltage AC transmission line: the high-frequency power supply includes an AC power supply P2, an isolating switch K2, a power frequency transformer T1, an isolating switch K1, a thyristor full-bridge rectifier module, an energy storage capacitor C0, a filter Inductor L0, reverse switching transistor full-bridge inverter module, resonant capacitor C1 and inductance L1; the AC power supply P2 is connected to the input end of the power frequency transformer T1 through the isolation switch K2, and the output end of the power frequency transformer T1 is through the isolation switch K1 is connected to the thyristor full-bridge rectifier module, and the thyristor full-bridge rectifier module is connected to the reverse switch transistor full-bridge inverter module through the energy storage circuit formed by the energy storage capacitor C0 and the filter inductor L0, and the reverse switch transistor full-bridge inverter module The output end of the module is connected to a series resonant circuit formed by a resonant capacitor C1 and a resonant inductance L3, and the output end of the series resonant circuit is connected to an input end of a high frequency transformer T.

By adopting this technical scheme: the AC voltage output by the AC power supply P2 is transformed by the power frequency transformer and then output to the thyristor full-bridge rectifier module to be converted into DC power, which is stored in the energy storage circuit composed of the energy storage capacitor C0 and the filter inductor L0, and then It is converted into a high-frequency bipolar square wave by the full-bridge inverter module of the reverse switching transistor (RSD), and connected to the high voltage through the series resonant unit composed of the resonant capacitor C1 and the resonant inductor L3 through the high-frequency transformer T and the resonant capacitor C The AC transmission line outputs high-frequency high-amplitude deicing current.

Another preferred solution is: the high-frequency power supply includes a DC power supply, an energy storage capacitor C0, a reverse switching transistor full-bridge inverter module, a resonant capacitor C1 and an inductor L1; the energy storage capacitor C0 is connected in parallel to the output terminal of the DC power supply, The DC power supply is sequentially connected to the industrial frequency transformer T1 through the reverse switching transistor full-bridge inverter module and the series resonant circuit formed by the resonant capacitor C1 and the resonant inductance L3.

By adopting this technical solution: the DC power output by the DC power supply is converted into a high-frequency bipolar square wave by the reverse switching transistor (RSD) full-bridge inverter module, and then passes through the high-frequency transformer after being resonant in series with the resonant capacitor C1 and the resonant inductor L3 T and resonance capacitor C are connected to the high-voltage AC transmission line.

More preferably, most of the high-frequency current output by the high-frequency power supply returns to the ground terminal of the transformer T through the ice-melting section AB, the isolation switch K6 and the first high-pass filter. Further preferably, the line resistance R of the line in the AB section is R≤0.1L1 compared with the impedance of the inductor L1.

In this way: the capacitor C2 and the line inductance of the AB section form a series resonant circuit, which reduces the equivalent non-resistive high-frequency impedance L0 of the AB section to approximately equal to 0. When the impedance of the line resistance R of the AB section is much smaller than L1, Most of the high-frequency current returns to the ground terminal of the transformer T through the AB section wire, the isolation switch K6, the first high-pass filter and the ground terminal, and the wire heats up, thereby removing the ice application on the wire and avoiding the impact of the high-frequency current on the deicing circuit. outside the influence of the power line.

The beneficial effect that the present invention has:

Compared with the prior art, the high-frequency power supply of the present invention can be directly installed in the transmission and transformation substation without being installed at the midpoint of the transmission line, which greatly reduces the installation difficulty, construction cost and maintenance cost of the deicing and anti-icing device. At the same time, the working Personnel do not need to travel long distances to the midpoint of the line for operation and maintenance, which significantly reduces labor costs and realizes quick response to dispatching instructions; the high-frequency power supply uses RSD as a power switch to output high-frequency and high-power currents, and high-frequency power supplies based on IGBTs and MOSFETs Compared with the high-frequency power supply, the cost of the high-frequency power supply of the present invention is significantly reduced, while the reliability and stability of the power system are significantly increased.

Description of drawings

Fig. 1 is the schematic diagram of principle of the present invention, wherein A-B section is the deicing section of high-voltage alternating current transmission line;

Fig. 2 is the structural representation of embodiment 1 of the present invention;

Fig. 3 is a schematic diagram of an internal structure of the high-frequency power supply module in Fig. 2;

FIG. 4 is a schematic diagram of another internal structure of the high-frequency power module in FIG. 2 .

detailed description

The present invention will be further described below in conjunction with the examples, but the protection scope of the present invention is not limited only to the examples.

Embodiment 1 of the present invention as shown in Figure 1-4:

An anti-icing device for wires of high-voltage AC transmission lines, including an ice-melting device and a high-pass filter; the two endpoints of a single AC wire of the AC transmission line that needs to be deiced are A terminal and B terminal respectively, which are called ice melting Section AB; the end point A of the ice-melting section AB that needs to be deiced is equipped with an ice-melting device, and the end point B of the other end is connected to a grounded second high-pass filter; the ice-melting device includes an inductor L1, a capacitor C, a capacitor C2, Isolating switch K, isolating switch K4, isolating switch K5, isolating switch K6, high-frequency power supply, capacitor C3, high-frequency transformer T and the first high-pass filter; the high-frequency power supply passes through the high-frequency transformer T, capacitor C, isolation The switch K and the capacitor C2 are connected to the input point of the A terminal of the ice-melting section AB, one end of the capacitor C2 is connected to one end of the isolation switch K, and the other end of the capacitor C2 is connected to the input point of the A terminal of the ice-melting section AB; One end of the inductance L1 is connected to the common end of the isolating switch K and the capacitor C2, the other end of the inductance L1 is connected to the common end of the isolating switch K4 and the capacitor C3, and one end of the capacitor C3 is connected to the common end of the isolating switch K4 and the inductance L1. The other end of the capacitor C3 is connected to the A-end output point of the ice-melting section AB, one end of the isolating switch K4 is connected to one end of the capacitor C3, and the other end of the isolating switch K4 is connected to one end of the first high-pass filter. The other end of the high-pass filter is grounded; one end of the isolating switch K5 is connected to the common end of the isolating switch K and the capacitor C2, and the other end is connected to the A-end output point of the ice-melting section AB; one end of the second high-pass filter is connected to the isolation One end of the switch K6, the other end of the second high-pass filter is grounded, and the other end of the isolating switch K6 is connected to the B end of the ice-melting section AB.

Wherein, the high-frequency power supply includes an AC power supply P2, an isolation switch K2, a power frequency transformer T1, an isolation switch K1, a thyristor full-bridge rectifier module, an energy storage capacitor C0, a filter inductor L0, and a reverse switching transistor full-bridge inverter module, Resonant capacitor C1 and inductance L1; the AC power supply P2 is connected to the input end of the power frequency transformer T1 through the isolation switch K2, and the output end of the power frequency transformer T1 is connected to the thyristor full-bridge rectifier module through the isolation switch K1, and the thyristor full bridge The rectifier module is connected to the reverse switching transistor full-bridge inverter module through the energy storage circuit formed by the energy storage capacitor C0 and the filter inductor L0, and the output terminal of the reverse switching transistor full-bridge inverter module is connected to the resonant capacitor C1 and the resonant inductor L3 to form a A series resonant circuit, the output end of the series resonant circuit is connected to the input end of the high frequency transformer T.

The high-frequency power supply can also be composed of a DC power supply, an energy storage capacitor C0, a reverse switching transistor full-bridge inverter module, a resonant capacitor C1 and a resonant inductor L3. Wherein, the energy storage capacitor C0 is connected in parallel to the output end of the DC power supply, and the DC power supply is sequentially connected to the high-frequency transformer T through the reverse switching transistor full-bridge inverter module and the series resonant circuit composed of the resonant capacitor C1 and the resonant inductor L3 input terminal.

In the figure: Section A-B is the line that needs to be deiced.

In practice, its working process is as follows: when the high-voltage AC transmission line is working normally and deicing is not needed, the isolating switch K5 is closed, the isolating switch K6, the isolating switch K, and the isolating switch K4 are all turned off, and the deicing device is removed from the power transmission system. Isolation, de-icer not working. When the AB section of the line needs to be deiced, K5 is disconnected, K, K6, and K4 are all closed, the high-frequency power supply outputs a high-frequency current through the high-frequency transformer T, and the capacitor C2 forms a series resonant circuit with the line inductance of the AB section, and the AB section The equivalent non-resistive high-frequency impedance L0 is reduced to approximately equal to 0, and the impedance of the AB section is basically only the line resistive impedance R. When the impedance of the line resistance R of the AB section is much smaller than L1, most of the high-frequency current The high-frequency deicing current of the line wires of the AB section is formed through the line wires of the AB section. In general, the ratio of R and L1 is R≤0.1L1, and this ratio value is a suggested optimal value, but in actual application, the ratio value should be designed according to the actual effect, not limited to this value. Inductors L1 and C3 resonate in series, and the total power frequency impedance of the two is close to or equal to 0, reducing or eliminating the influence of L1 on the power frequency line.

Finally, it should be noted that: the above embodiments are only used to illustrate the present invention and are not intended to limit the technical solutions described in the present invention. Therefore, although the specification has described the present invention in detail with reference to the above-mentioned various embodiments, the skilled artisan Those of ordinary skill in the art should understand that the present invention can still be modified or equivalently replaced, and all technical solutions and improvements that do not depart from the spirit and scope of the present invention should be included in the claims of the present invention.

Claims (6)

1. a HVAC power transmission line conductor ice prevention device, it is characterised in that: include deicing device and high pass filter；Institute Two end points of the single exchange wire stating the transmission line of alternation current needing deicing are respectively side a and b, referred to as ice-melt section AB； The terminal A end needing ice-melt section AB of deicing installs deicing device, and the terminal B end of the other end connects the second high-pass filtering of ground connection Device；Described deicing device includes inductance L1, electric capacity C, electric capacity C2, disconnecting switch K, disconnecting switch K4, disconnecting switch K5, keeps apart Close K6, high frequency electric source, electric capacity C3, high frequency transformer T and the first high pass filter；Described high frequency electric source passes sequentially through high frequency transformation Device T, electric capacity C, disconnecting switch K and electric capacity C2 access the input point of the A end of ice-melt section AB, and one end of described electric capacity C2 connects isolation One end of switch K, the other end of described electric capacity C2 connects the input point of the A end of ice-melt section AB；Described inductance L1 one end connect every Leaving pass K and the common port of electric capacity C2, the described inductance L1 other end connects disconnecting switch K4 and the common port of electric capacity C3, described electricity The one end holding C3 connects disconnecting switch K4 and the common port of inductance L1, and the other end of described electric capacity C3 connects the A end of ice-melt section AB Output point, one end of described disconnecting switch K4 connects one end of electric capacity C3, and it is high that the other end of described disconnecting switch K4 connects first One end of bandpass filter, the other end ground connection of described first high pass filter；One end of described disconnecting switch K5 connects and keeps apart Closing K and the common port of electric capacity C2, the other end connects the A end output point of ice-melt section AB；One end of described second high pass filter is even Connecing one end of disconnecting switch K6, the other end ground connection of described second high pass filter, the other end of described disconnecting switch K6 connects The B end of ice-melt section AB.

2. a kind of HVAC power transmission line conductor ice prevention device, it is characterised in that: described high frequency electric source Including alternating current power supply P2, disconnecting switch K2, Industrial Frequency Transformer T1, disconnecting switch K1, IGCT full-bridge rectification module, storage capacitor C0, filter inductance L0, reverse switch transistor full-bridge inverting module, resonant capacitance C1 and resonant inductance L3；Described alternating current power supply P2 connects the input of Industrial Frequency Transformer T1 through disconnecting switch K2, the outfan of described Industrial Frequency Transformer T1 connects through disconnecting switch K1 Connect IGCT full-bridge rectification module, the energy storage that described IGCT full-bridge rectification module is constituted through storage capacitor C0, filter inductance L0 Circuit connects reverse switch transistor full-bridge inverting module, and the outfan of described reverse switch transistor full-bridge inverting module connects The series resonant circuit that resonant capacitance C1 and resonant inductance L3 is constituted, the outfan of described series resonant circuit connects high frequency transformation The input of device T.

3. a kind of HVAC power transmission line conductor ice prevention device, it is characterised in that: described high frequency electric source Including DC source, storage capacitor C0, reverse switch transistor full-bridge inverting module, resonant capacitance C1 and resonant inductance L3；Storage The outfan of DC source can be parallel to by electric capacity C0, described DC source sequentially through reverse switch transistor full-bridge inverting module and The series resonant circuit being made up of resonant capacitance C1 and resonant inductance L3 is connected to the input of high frequency transformer T.

4. a kind of high-voltage AC transmission line conductor ice prevention device, it is characterised in that: described electric capacity C2 is with high The line inductance composition series resonant circuit of pressure transmission line AB section, high frequency electric passes through the outfan of high frequency transformer T, electric capacity C, disconnecting switch K, electric capacity C2, ice-melt section AB, disconnecting switch K6, the second high pass filter return to the earth terminal of transformator T.

5. a kind of HVAC power transmission line conductor ice prevention device, it is characterised in that: described inductance L1's Resistance value should be greater than the resistance R of AB section circuit, circuit resistance R of the impedance of described inductance L1 and AB section circuit preferably than Value is R≤0.1L1；Electric capacity C2 and AB section line inductance L0 forms series resonant circuit, reduces the non-resistive high frequency of equivalence of AB section Impedance Z 0, the preferred ratio of the non-resistive high-frequency resistance Z0 of equivalence of described AB section and circuit resistance R of AB section circuit be Z0≤ 0.5R。

6. a HVAC power transmission line conductor ice prevention device combination, it is characterised in that: by three sets as claim 1-5 is appointed The HVAC power transmission line conductor ice prevention device described in a claim of anticipating combines, and constitutes three-phase AC line and prevents Ice.