Reversing transmission of direct current through superconductive cable line

FIELD: electricity.

SUBSTANCE: terminal converting substations (1) and (2) with control systems (3) and (4) are coupled by double-wire superconductive cable line (5). At the line ends there are direct voltage sensors (6) and (7). In the direct-current transmission circuit there is introduced unit (8) for comparing their readings and bidirectional switches (9) and (10) switched on between ends of the line (5) at substations (1) and (2). The unit (8) is coupled with galvanic isolation by its inputs to outputs of sensors (6) and (7), and by its output to inputs of control systems (3) and (4) of substations (1) and (2) and to control inputs of bidirectional switches (9) and (10).

EFFECT: reducing risk of damage for high-temperature superconductive cable line operating as a part of reversing direct current transmission system when high-temperature superconductive cable is out of superconductive state.

1 dwg

 

Area of technology

The invention relates to Converter equipment and can be used in the power industry.

The level of technology

Known circuits of the DC transmission (APT), including cable lines DC [1, 2, 3]. As a prototype the selected diagram PPT, the application of which to the underwater sea cable described in [4].

The prototype contains terminal Converter stations control systems associated two-wire cable line equipped with sensors and DC voltage at its ends. In the control system includes sets of protections, including protection of the terminal equipment of substations from voltage surges. However, in the case of superconducting cable based on high-temperature superconductivity (HTS cable), which is characterized, on the one hand, the inadmissibility of any periods of heating wires regardless of the cause (deterioration of cooling or increasing the current), and on the other, the high price, the prototype does not provide protection of HTS cable for violation of its operating mode.

Summary of the invention

The technical result of the invention - reducing the risk of damage to the HTS cable line, which runs within the PPT reversible, in case of HTSC cable from the superconducting state.

Reverse IPT with�keeps EOL Converter station control systems, associated two-wire superconducting cable line equipped with sensors and DC voltage at its ends.

In the diagram PPT reversible with superconducting cable entered the block of comparison of sensors and bi-directional switches between the ends of the lines at the substations, wherein the comparison unit is connected with galvanic isolation the inputs to the outputs of the sensors, and output - to the inputs of the control systems of each of the substations and to the control inputs of the bidirectional switches.

This allows us to obtain the above technical result.

The implementation of the invention

Summary of the invention explains the scheme shown in the drawing.

The figure shows a terminal Converter stations 1 and 2 control systems 3 and 4. Substation 1 and 2 are connected two-wire superconducting cable line 5. At its ends installed sensors 6 and 7 DC voltage. In the scheme the company entered block 8 comparison of their testimony, and bidirectional switches 9 and 10 are connected between the ends of the line 5 at the substations 1 and 2. Block 8 is connected with galvanic isolation the inputs to the outputs of the sensors 6 and 7, and output - to the inputs of control systems 3 and 4 substations 1 and 2 and to the control inputs of the bidirectional switches 9 and 10.

The inventive device operates as follows.

One of the substations 1 or 2 conversion�izes its voltage AC to DC, which is passed via line 5 to the other substation. Sensors 6 and 7 control the voltage at the ends of the two-wire line 5 (between points a and b on the side of the substation 1 and between points c and d from the substation 2). In the operating mode line 5 is in the superconducting state and the values of the voltages measured by the sensors 6 and 7 are almost identical (the voltage difference is determined by the losses in transition cable boxes).

Thus the bidirectional switches 9 and 10 are not included and do not affect the operation of the device.

The appearance of a potential difference ΔU=U1-U2where U1- the voltage at one end of the line 5, a U2- the voltage at its second end, means output line 5 of the superconducting state. The reason for this may be as the excess of temperature of the cable core in excess of 78 K - top temperature of existence of superconductivity and excess current density, above which there can be superconductivity. In both cases, due to the voltage drop on the veins of the cable there is a potential difference, the module where|ΔU|=|U1U2|>0.

Unit 8 compares the readings of the sensors 6 and 7 in accordance with the expression |ΔU|=|U1U2|>δwhere δ is a non-zero threshold (setpoint), is triggered and emits a corresponding signal. This signal acts on the control system 3 and 4, which remove the control pulses from the transducers of the two substations, and includes switches 9 and 10.

The need to turn the switches 9 and 10 due to the fact that after the removal of control pulse transformers of the substations 1 and 2 not instantly cease to issue and currents. The inclusion of the switches 9 and 10 simultaneously with the issuance of the systems 3 and 4 signals for withdrawal of the control pulses of the transducers avoids the occurrence of these currents on HTS cable line. Switches 9 and 10 can be, for example, high voltage bidirectional thyristor valves, which, joining, enclose current from the substations 1 and 2.

Thus regardless of the direction of DC transmission (from substation 1 to substation 2 or back), which took place in the time of the accident, a cable line 5 is de-energized almost instantly and regardless of the current phase of the converted voltage AC power.

The use of galvanic junctions for the connection unit 8 � remote from the blocks, placed at substations 1 and 2, provides for the immunity of these compounds.

As can be seen from the above, the invention reduces the risk of damage to the HTS cable line when the output from the superconducting state regardless of the cause of such withdrawal.

Sources of information

1. Vassilisios G. Agelidis, Nicolas Flourentzou. Recent Advances in High-Voltage Direct-Current Power Transmission Systems // ABB AB Corporate Research SE-721 78 Vasteras.

2. J. P. Kjergaard and others. The new Storebaelt HVDC project for interconnecting the eastern and western Denmark. // CIGRE 2008, B4-104.

3. Ronstrom L. and others. The Estlink HVDC Light Transmission Systems // CIGRE Regional Meeting, 2007, Tallinn, Estonia.

4. Jochen Kreusel. Line DC transmission for the world's largest offshore wind power plant, / / ABB review, No. 4, 2008, pp. 40-43.

Reversible DC transmission containing terminal Converter stations control systems associated two-wire superconducting cable line, sensors DC voltage at its ends and a unit for comparing the sensor readings, while between the ends of the lines at the substations included bidirectional switches, the unit of comparison is connected with galvanic isolation the inputs to the outputs of the sensors, and output - to the inputs of the control systems of the substations and to the control inputs of the bidirectional switches.



 

Same patents:

FIELD: electricity.

SUBSTANCE: use: in the field of electric engineering. The device comprises input and output buses and switching elements, which are made in the form of a group of primary ones, according to the number of energy generation channels, providing for their connection to a power supply bus in accordance with the specified conditions, and in the form of a group of secondary ones, in accordance with the number of loads, providing for their connection to the power supply bus in accordance with information on the procedure of connection, realised in the introduced control device, which is connected with the help of a multiplex information bus to all switching elements, at the same time the switching element based on a semiconductor electronic key comprises sensors of current and voltage, sensors of environmental parameters, connected to a microcontroller, interacting via an information multiplex bus with a control device, which makes it possible to perform diagnostics and switching of energy generation and consumption channels in accordance with information on reference values of currents, voltages and parameters (for instance, temperature of the electronic key) of environment stored in the memory of the microcontroller.

EFFECT: expansion of functional capabilities.

2 dwg

FIELD: electricity.

SUBSTANCE: application: in the field of electrical engineering. The system contains at least one segment (1) of electric mains, a bank of capacitors (2), at least one voltage converter (3) connected between the bank of capacitors (2) and the segment (1) of electric mains, a regulator (4) with input (5) and at least one output (6). The voltage converter (3) is reversible and has a control input (7) connected to the output (6) of the regulator (4), to which input (5) voltage of the bank of capacitors (2) is supplied, moreover the voltage converter (3) is made so that against a signal at the control input (7) it can change parameters of its volt-ampere curve at outputs from the side of the segment (1) of electric mains, and the regulator (4) is designed to maintain voltage of the bank of capacitors (2) within the set range in static mode of the electric mains and at dynamic disturbance in the electric mains not to change the signal at its output (6).

EFFECT: increasing usage efficiency of the bank of capacitors in order to amplify pulse power of the electric mains.

8 cl, 3 dwg

FIELD: electricity.

SUBSTANCE: system comprises transformer substations and cables, which are installed on a group of wells, the total capacity of which is not more than three average capacities of wells at the water conduit branch with total number of wells in the branch exceeding 12.

EFFECT: increased reliability of system operation and reduced network of cables.

1 dwg

FIELD: electricity.

SUBSTANCE: power supply system comprises an inverter (1), connected with the first end (2a, 2b, 2c) of each winding (3a, 3b, 3c) in three phases of the engine, and a contactor (9) of disconnection, arranged at least on two of the specified phases between the inverter and the specified first end of the appropriate winding, at the same time the second ends (5a, 5b, 5c) of three windings are connected to the common point (6). The system also comprises an organ (11) of disconnection of a neutral line, arranged at least in two phases between the common point and the specified second end of the appropriate winding.

EFFECT: higher accuracy and reliability.

4 cl, 2 dwg

FIELD: electricity.

SUBSTANCE: combined device (10) for control of power transmission between two centres (42, 46) of DC network and supply of AC motor (13) comprises unit (19) of two three-phase inverters, every of which includes three switching elements connected to specified motor (13), at the same time motor (13) comprises three stator windings connected to two three-phase inverters. Device also comprises module (23) of control of specified unit (19), providing for possibility of controlled power transmission based on DC, stabilisation of DC voltage at one of two specified centres as the other one disconnects and motor (13) control.

EFFECT: reduced risks of instability and provision of quality and transmission of power both in normal and emergency mode.

4 cl, 7 dwg

FIELD: engines and pumps.

SUBSTANCE: proposed device comprises engine electric supply circuit independent of aircraft onboard electric circuit and circuits of excitation, control or servo control of engine electrical hardware elements. Note here that engine electric supply circuit comprises: first bus 24 to distribute DC or AC voltages for circuits of excitation, control or servo control of engine electrical hardware first elements, second bus 30 to distribute DC or AC voltages for circuits of excitation, control or servo control of engine electrical hardware other elements that required higher electric power compared with that consumed by aforesaid first elements, and third bus that incorporates communication line to receive power from electric power source and connected with said first and second buses for electric power supply.

EFFECT: expanded operating performances and higher reliability.

11 cl, 9 dwg

FIELD: electrical engineering.

SUBSTANCE: invention relates to electrified railway power supply systems. Proposed substation comprises converter transformer (1), rectifier-inverter unit (2), power storage capacitor bank (4) and reactor (5). Aforesaid power storage capacitor bank (4) has its one end connected to positive terminal via primary contactor (7) and stabiliser or limiter (3). Its other end is connected with generic point of reactor (5) and rail (9). Current stabiliser or limiter (3) is connected to shunting contactor (6). One leadout of discharge contactor (8) is connected to generic point of reactor (5) and rail (9), the other one being connected to generic point of current stabiliser or (3) and primary contactor (7). Discharge contactor (8) is interlocked with primary contactor (7).

EFFECT: higher voltage stability, higher reliability, reduced losses.

1 dwg

FIELD: electricity.

SUBSTANCE: application: for field instrument powering. Electronic unit of field instrument contains current stabiliser with current flowing in it under action of supply voltage provided by external current source, internal operating-analysing circuit for field instrument control and internal feed circuit. Feed circuit comprises voltage regulator through which at least temporarily the first partial feed current flows and which provides electronic unit of field instrument with the first internal useful voltage which is essentially constantly adjusted and is kept on preset level, and the second voltage regulator over which at least temporarily the second partial feed current flows which provides electronic unit of field instrument with the second useful voltage varying within preset range, and voltage stabiliser through which at least temporarily the third partial feed current flows and which serves for adjusting and keeping internal input voltage on preset level. In operating-analysing circuit at least temporarily both the first useful current under action of the first useful voltage and the second useful current under action of the second useful voltage flows.

EFFECT: increase in efficiency factor of field instrument with power consumption optimization.

41 cl, 13 dwg

FIELD: electricity.

SUBSTANCE: system contains a power unit, connected to its output lines of the switchboards of circuits of the feed circuits of instruments and the control unit of the switchboards, the additional switchboards, connected to the output lines of the power unit, which through the first and second resistors with identical ratings are connected with the first input of the control-measuring equipment and on the case ("ground") of the article, and through the third and fourth resistors with identical ratings - with the second input of control-measuring equipment, the simulator of insulation resistance of the inputs is connected to the outputs of additional switchboards, and by a common point is connected to the case ("ground") of the article, thus the simulator is executed in the form of additional resistors whose first outputs are connected to its inputs, and the second outputs are connected to its common point.

EFFECT: increase in the operational reliability of the distribution system of electric power by guaranteeing of reliable control of insulation resistance of the system and the equipment fed by it.

2 cl, 2 dwg

FIELD: electricity.

SUBSTANCE: electric power distribution system includes power supply unit, hardware power supply circuit switches connected to power supply unit buses, hardware power supply circuit switch control unit and resistors which have equal nominal values in pairs. Output buses of power supply unit are connected with item housing ("grounding") via the first pair of additional resistors, with hardware power supply circuits also linked with item housing ("grounding") via the other pairs of additional resistors.

EFFECT: improvement of system serviceability by static electricity charges removal and voltage removal at switches.

1 dwg

FIELD: electrical energy transmission to stationary and mobile users.

SUBSTANCE: proposed method makes use of ac voltage generator and includes voltage transfer from generator to low-voltage winding of Tesla coil; connection of one of high-voltage winding leads of this transformer to one of output terminals of electrical equipment being fed (load) and setting of resonant oscillations in electric circuit; rectification of high-frequency ac voltage and current of step-up Tesla coil high-voltage winding by connecting internal lead of this step-up Tesla coil winding to high-frequency diode; and transfer of rectified voltage and current to load over single-wire line. As an alternative, high-frequency ac voltage across high-voltage winding of step-up Tesla coil is rectified by connecting internal lead of Tesla coil high-voltage winding to diode-capacitor unit, doubling voltage, and transmitting rectified voltage and current to load over two-wire line.

EFFECT: enhanced effectiveness, reduced loss, enhanced reliability of electrical energy transmission.

17 cl, 13 dwg

FIELD: railway and industrial transport and underground transport.

SUBSTANCE: proposed dc traction power supply system includes traction substations and contact systems of several parallel tracks supplied by said substations with sectionalizing boxes approximately in middle of inter-substation zones, or without such sectionalizing boxes. Power supply of running trains is provided mainly by superconducting cable line laid parallel to contact system of each track or both tracks and connected by wires of contact system in several points over their length.

EFFECT: reduced power losses in traction system, increased traffic capacity and distance between traction substations.

3 cl, 5 dwg

FIELD: electricity.

SUBSTANCE: four resistors and test instrument are introduced into electric power distribution system comprising power supply unit, hardware power supply circuit switches connected to power supply unit buses and hardware power supply circuit switch control unit, power supply unit buses being linked with instrument input 1 and item housing ("grounding") via resistor 1 and 2, with the second instrument input connected with power supply unit buses via resistor 3 and 4 with equal nominal value.

EFFECT: improvement of system serviceability by ensuring insulation resistance control in electric power distribution system and hardware fed by system.

1 dwg

FIELD: electricity.

SUBSTANCE: electric power distribution system includes power supply unit, hardware power supply circuit switches connected to power supply unit buses, hardware power supply circuit switch control unit and resistors which have equal nominal values in pairs. Output buses of power supply unit are connected with item housing ("grounding") via the first pair of additional resistors, with hardware power supply circuits also linked with item housing ("grounding") via the other pairs of additional resistors.

EFFECT: improvement of system serviceability by static electricity charges removal and voltage removal at switches.

1 dwg

FIELD: electricity.

SUBSTANCE: system contains a power unit, connected to its output lines of the switchboards of circuits of the feed circuits of instruments and the control unit of the switchboards, the additional switchboards, connected to the output lines of the power unit, which through the first and second resistors with identical ratings are connected with the first input of the control-measuring equipment and on the case ("ground") of the article, and through the third and fourth resistors with identical ratings - with the second input of control-measuring equipment, the simulator of insulation resistance of the inputs is connected to the outputs of additional switchboards, and by a common point is connected to the case ("ground") of the article, thus the simulator is executed in the form of additional resistors whose first outputs are connected to its inputs, and the second outputs are connected to its common point.

EFFECT: increase in the operational reliability of the distribution system of electric power by guaranteeing of reliable control of insulation resistance of the system and the equipment fed by it.

2 cl, 2 dwg

FIELD: electricity.

SUBSTANCE: application: for field instrument powering. Electronic unit of field instrument contains current stabiliser with current flowing in it under action of supply voltage provided by external current source, internal operating-analysing circuit for field instrument control and internal feed circuit. Feed circuit comprises voltage regulator through which at least temporarily the first partial feed current flows and which provides electronic unit of field instrument with the first internal useful voltage which is essentially constantly adjusted and is kept on preset level, and the second voltage regulator over which at least temporarily the second partial feed current flows which provides electronic unit of field instrument with the second useful voltage varying within preset range, and voltage stabiliser through which at least temporarily the third partial feed current flows and which serves for adjusting and keeping internal input voltage on preset level. In operating-analysing circuit at least temporarily both the first useful current under action of the first useful voltage and the second useful current under action of the second useful voltage flows.

EFFECT: increase in efficiency factor of field instrument with power consumption optimization.

41 cl, 13 dwg

FIELD: electrical engineering.

SUBSTANCE: invention relates to electrified railway power supply systems. Proposed substation comprises converter transformer (1), rectifier-inverter unit (2), power storage capacitor bank (4) and reactor (5). Aforesaid power storage capacitor bank (4) has its one end connected to positive terminal via primary contactor (7) and stabiliser or limiter (3). Its other end is connected with generic point of reactor (5) and rail (9). Current stabiliser or limiter (3) is connected to shunting contactor (6). One leadout of discharge contactor (8) is connected to generic point of reactor (5) and rail (9), the other one being connected to generic point of current stabiliser or (3) and primary contactor (7). Discharge contactor (8) is interlocked with primary contactor (7).

EFFECT: higher voltage stability, higher reliability, reduced losses.

1 dwg

FIELD: engines and pumps.

SUBSTANCE: proposed device comprises engine electric supply circuit independent of aircraft onboard electric circuit and circuits of excitation, control or servo control of engine electrical hardware elements. Note here that engine electric supply circuit comprises: first bus 24 to distribute DC or AC voltages for circuits of excitation, control or servo control of engine electrical hardware first elements, second bus 30 to distribute DC or AC voltages for circuits of excitation, control or servo control of engine electrical hardware other elements that required higher electric power compared with that consumed by aforesaid first elements, and third bus that incorporates communication line to receive power from electric power source and connected with said first and second buses for electric power supply.

EFFECT: expanded operating performances and higher reliability.

11 cl, 9 dwg

FIELD: electricity.

SUBSTANCE: combined device (10) for control of power transmission between two centres (42, 46) of DC network and supply of AC motor (13) comprises unit (19) of two three-phase inverters, every of which includes three switching elements connected to specified motor (13), at the same time motor (13) comprises three stator windings connected to two three-phase inverters. Device also comprises module (23) of control of specified unit (19), providing for possibility of controlled power transmission based on DC, stabilisation of DC voltage at one of two specified centres as the other one disconnects and motor (13) control.

EFFECT: reduced risks of instability and provision of quality and transmission of power both in normal and emergency mode.

4 cl, 7 dwg

FIELD: electricity.

SUBSTANCE: power supply system comprises an inverter (1), connected with the first end (2a, 2b, 2c) of each winding (3a, 3b, 3c) in three phases of the engine, and a contactor (9) of disconnection, arranged at least on two of the specified phases between the inverter and the specified first end of the appropriate winding, at the same time the second ends (5a, 5b, 5c) of three windings are connected to the common point (6). The system also comprises an organ (11) of disconnection of a neutral line, arranged at least in two phases between the common point and the specified second end of the appropriate winding.

EFFECT: higher accuracy and reliability.

4 cl, 2 dwg

Up!