CN107833772B - Current transfer method for main circuit topology of artificial zero crossing technology - Google Patents
Current transfer method for main circuit topology of artificial zero crossing technology Download PDFInfo
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- CN107833772B CN107833772B CN201711167842.6A CN201711167842A CN107833772B CN 107833772 B CN107833772 B CN 107833772B CN 201711167842 A CN201711167842 A CN 201711167842A CN 107833772 B CN107833772 B CN 107833772B
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H9/00—Details of switching devices, not covered by groups H01H1/00 - H01H7/00
- H01H9/54—Circuit arrangements not adapted to a particular application of the switching device and for which no provision exists elsewhere
- H01H9/56—Circuit arrangements not adapted to a particular application of the switching device and for which no provision exists elsewhere for ensuring operation of the switch at a predetermined point in the ac cycle
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Abstract
The invention discloses a current transfer method of a main circuit topology of an artificial zero crossing technology, wherein the main circuit topology comprises a main current path and a current transfer circuit which are connected in parallel, the main current path is formed by sequentially connecting a mechanical switch S and a primary coil L1 of a saturation transformer T in series, the current transfer circuit is formed by sequentially connecting a pre-charging capacitor C, a control switch FV and a secondary coil L2 of the saturation transformer T in series, and the connecting end of the capacitor C and the mechanical switch S is a pre-charging cathode; the primary coil and the secondary coil of the saturation transformer T have opposite directions of exciting magnetic potential in the current transfer process, and can rapidly exit from the saturation state near the zero crossing of the current of the mechanical switch S, so that the inductance of a transfer loop is remarkably increased, the current change rate near the zero point of the current of the mechanical switch S is greatly reduced, and the high-current breaking reliability of the mechanical switch S is improved.
Description
Technical Field
The invention belongs to the technical field of circuit breakers, and particularly relates to a current transfer method of a main circuit topological structure based on an artificial zero crossing technology.
Background
A typical circuit breaker implemented based on an artificial zero crossing technology is shown in fig. 1, and a reverse high-frequency current provided by an LC current transfer circuit is superimposed with a short-circuit current in a main mechanical switch S to quickly generate a current zero crossing point, so as to realize quick breaking of the circuit. Particularly, aiming at direct current breaking, the direct current zero crossing point can be quickly and effectively manufactured by utilizing an artificial zero crossing technology, and the technology is simple and mature and is an important development direction of the current medium-high voltage direct current circuit breaker.
In order to realize the quick zero crossing of the S current of the main mechanical switch and reduce the volume of the whole circuit breaker, in a typical manual zero-crossing type circuit breaker scheme, an LC transfer circuit works in a high-frequency pulse state, and the current change rate is very high when the current of the mechanical switch passes through the zero, so that the reliable recovery of a medium after an arc is not facilitated, and the large-current breaking failure is easily caused. In order to improve the high-current breaking reliability, on one hand, the current change rate near the current zero point of the mechanical switch can be reduced by increasing the commutation capacitor C and the inductor L, but on the premise of meeting the requirement of high-current breaking capacity, the volumes of the commutation capacitor C and the inductor L can be greatly increased.
On the other hand, the saturable reactor Ls is connected in series with the S branch of the mechanical switch to reduce the current change rate near the current zero point, as shown in FIG. 2. When the current of a coil Ls wound on the iron core is large, the magnetic permeability of the iron core is reduced due to magnetic saturation of the iron core, so that the inductance of the coil is small; when the current of the coil Ls is reduced to be near the zero point, the iron core is out of saturation, so that the magnetic conductivity is increased, and the inductance of the coil is remarkably increased. However, due to the hysteresis characteristic of the actual iron core, demagnetization can occur along a hysteresis loop in the process of reducing the current of the coil Ls, the magnetic permeability near the current zero point cannot be obviously increased, the inductance of the coil is not obviously increased, the conventional saturable reactor cannot obviously slow down the current reduction speed before the current of the mechanical switch crosses zero, and the current reduction speed can only be limited after the current crosses zero, as shown in fig. 5. The saturable reactor capable of effectively reducing the current change rate before the current zero point needs to be specially designed, and the volume is very large.
Disclosure of Invention
The invention aims to design a main circuit topological structure of an artificial zero crossing technology according to the defects of the prior art, and the main circuit topological structure can greatly reduce the current change rate of a mechanical switch S before the current zero crossing on the premise of meeting the volume requirement and obviously improve the high-current breaking reliability of the mechanical switch S.
The technical scheme adopted by the invention for solving the technical problems is as follows: an artificial zero crossing technology main circuit topology comprises a main current path and a current transfer circuit which are connected in parallel, wherein the main current path is formed by sequentially connecting a mechanical switch S and a primary coil L1 of a saturation transformer T in series, the current transfer circuit is formed by sequentially connecting a pre-charging capacitor C, a control switch FV and a secondary coil L2 of the saturation transformer T in series, and the connecting end of the capacitor C and the mechanical switch S is a pre-charging negative electrode; the current directions of the same-name ends of a primary coil L1 and a secondary coil L2 of the saturation transformer T are opposite, the turn ratio of the primary coil L1 to the secondary coil L2 is N1: N2, wherein N1 is larger than N2, the saturation transformer T starts to be deeply saturated near the maximum transfer current point I0 of the mechanical switch S, and the saturation transformer T has hysteresis characteristics.
The invention also discloses a current transfer method of the main circuit topology of the artificial zero crossing technology, which comprises the following steps:
1) in normal operation, the mechanical switch S is closed, current flows through the mechanical switch S and the primary coil L1 of the saturation transformer T, and the inductance value of the primary coil L1 of the saturation transformer T is small due to deep saturation of the saturation transformer T;
2) when zero-crossing breaking of the mechanical switch S is required to be realized, the mechanical switch S is firstly disconnected to generate electric arc, then the switch FV is controlled to be switched on, and the pre-charging capacitor C discharges through a loop formed by the control switch FV, a secondary coil L2 of the saturation transformer T, a primary coil L1 of the saturation transformer T and an arc gap of the mechanical switch S, so that the current is of the mechanical switch S is reduced, the current ic of the capacitor C is increased, and current transfer is realized;
3) the equivalent excitation magnetic potential of the saturation transformer T is N1 is-N2 ic, in the stage of current starting transfer, is larger and ic is smaller, the equivalent excitation magnetic potential is a positive value and has a larger value, the saturation transformer T does not obviously exit a deep saturation state, the inductance values of a primary coil L1 and a secondary coil L2 of the saturation transformer T are small, and the current transfer speed is very high;
4) with the progress of the current transfer process, the equivalent excitation magnetic potential of the saturation transformer T is gradually reduced from a positive value and becomes a negative value before the current of the mechanical switch S passes zero, and due to the hysteresis characteristic, the inductance values of the primary coil L1 and the secondary coil L2 of the saturation transformer T are still smaller when the equivalent excitation magnetic potential is zero, so that the current transfer process is not obviously slowed down;
5) when the equivalent excitation magnetic potential of the saturation transformer T is reduced to a negative value, the inductance values of the primary coil L1 and the secondary coil L2 of the saturation transformer T are rapidly increased near the coercive current-I1, the current change rate near the zero crossing of the current of the mechanical switch S is greatly reduced, and therefore the breaking reliability of the mechanical switch S is improved.
The invention has the beneficial effects that: according to the invention, mutual cancellation of the excitation magnetic potentials of the primary coil and the secondary coil of the saturation transformer T is realized in the current transfer process, so that the saturation state is rapidly exited before the current of the mechanical switch S passes zero, on the premise of meeting the volume requirement, the inductance value near the zero point of the transfer loop current is effectively increased, the current change rate before the current of the mechanical switch S passes zero is greatly reduced, and the high-current breaking reliability of the mechanical switch S is remarkably improved.
Drawings
Fig. 1 is a main circuit topology of a typical manual zero-crossing circuit breaker in the prior art;
FIG. 2 is a prior art improved artificial zero crossing technique main circuit topology;
FIG. 3 is a main circuit topology scheme of the artificial zero crossing technique of the present invention;
FIG. 4 is a schematic diagram of the hysteresis characteristics of a saturation transformer;
fig. 5 is a current comparison of a mechanical switch in a prior art solution and in a solution according to the invention.
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings.
Referring to fig. 3, the invention discloses an artificial zero crossing technology main circuit topology, which comprises a main current path and a current transfer circuit which are connected in parallel, wherein the main current path is formed by sequentially connecting a mechanical switch S and a primary coil L1 of a saturation transformer T in series, the current transfer circuit is formed by sequentially connecting a pre-charging capacitor C, a control switch FV and a secondary coil L2 of the saturation transformer T in series, and a connecting end of the capacitor C and the mechanical switch S is a pre-charging negative electrode.
The current directions of the same-name ends of a primary coil L1 and a secondary coil L2 of the saturation transformer T are opposite, the turn ratio of the primary coil L1 to the secondary coil L2 is N1: N2, wherein N1 is larger than N2, the saturation transformer T starts to be deeply saturated near the maximum transfer current point I0 of the mechanical switch S, and the saturation transformer T has hysteresis characteristics.
The invention also discloses a current transfer method of the main circuit topology of the artificial zero crossing technology, which comprises the following steps:
1) in normal operation, the mechanical switch S is closed, current flows through the mechanical switch S and the primary coil L1 of the saturation transformer T, and the inductance value of the primary coil L1 of the saturation transformer T is small due to deep saturation of the saturation transformer T;
2) when zero-crossing breaking of the mechanical switch S is required to be realized, the mechanical switch S is firstly disconnected to generate electric arc, then the switch FV is controlled to be switched on, and the pre-charging capacitor C discharges through a loop formed by the control switch FV, a secondary coil L2 of the saturation transformer T, a primary coil L1 of the saturation transformer T and an arc gap of the mechanical switch S, so that the current is of the mechanical switch S is reduced, the current ic of the capacitor C is increased, and current transfer is realized;
3) the equivalent excitation magnetic potential of the saturation transformer T is N1 is-N2 ic, in the stage of current starting transfer, is larger and ic is smaller, the equivalent excitation magnetic potential is a positive value and has a larger value, the saturation transformer T does not obviously exit a deep saturation state, the inductance values of a primary coil L1 and a secondary coil L2 of the saturation transformer T are small, and the current transfer speed is very high;
4) with the progress of the current transfer process, the equivalent excitation magnetic potential of the saturation transformer T is gradually reduced from a positive value and becomes a negative value before the current of the mechanical switch S passes zero, and due to the hysteresis characteristic, the inductance values of the primary coil L1 and the secondary coil L2 of the saturation transformer T are still smaller when the equivalent excitation magnetic potential is zero, so that the current transfer process is not obviously slowed down;
5) when the equivalent excitation magnetic potential of the saturation transformer T is reduced to a negative value, the inductance values of the primary coil L1 and the secondary coil L2 of the saturation transformer T are rapidly increased near the coercive current-I1, the current change rate near the zero crossing of the current of the mechanical switch S is greatly reduced, and therefore the breaking reliability of the mechanical switch S is improved.
It can be seen that by introducing the primary coil L1 and the secondary coil L2 of the saturation transformer T in the main current path and the current transfer circuit, respectively, and making their exciting magnetic potentials during the current transfer cancel each other out, as a result, the exciting magnetic potential becomes negative before the current zero-crossing of the mechanical switch S, the saturation transformer T rapidly exits the saturation state, and the hysteresis characteristic of the saturation transformer T is as shown in fig. 4. On the premise of meeting the volume requirement, the equivalent inductance of the transfer loop near the zero point of the current is effectively increased, so that the current change rate of the mechanical switch S before the zero crossing of the current can be greatly reduced, and as shown in fig. 5, the high-current breaking reliability of the mechanical switch S is remarkably improved.
The above-described embodiments are merely illustrative of the principles and effects of the present invention, and some embodiments may be applied, and it will be apparent to those skilled in the art that various changes and modifications may be made without departing from the inventive concept of the present invention, and these embodiments are within the scope of the present invention.
Claims (1)
1. A current transfer method of an artificial zero crossing technology main circuit topology is characterized in that based on a main circuit topology formed by connecting a main current path and a current transfer circuit in parallel, the main current path is formed by sequentially connecting a mechanical switch S and a primary coil L1 of a saturation transformer T in series, the current transfer circuit is formed by sequentially connecting a pre-charging capacitor C, a control switch FV and a secondary coil L2 of the saturation transformer T in series, and the connecting end of the capacitor C and the mechanical switch S is a pre-charging negative electrode; the current directions of the same-name ends of a primary coil L1 and a secondary coil L2 of the saturation transformer T are opposite, the turn ratio of the primary coil L1 to the secondary coil L2 is N1: N2, wherein N1 is greater than N2, the saturation transformer T starts to be deeply saturated near the maximum transfer current point I0 of a mechanical switch S, and the saturation transformer T has hysteresis characteristics;
the method comprises the following steps:
1) in normal operation, the mechanical switch S is closed, and current flows through the mechanical switch S and the primary coil L1 of the saturation transformer T;
2) when zero-crossing breaking of the mechanical switch S is required to be realized, the mechanical switch S is firstly disconnected to generate electric arc, then the switch FV is controlled to be switched on, and the pre-charging capacitor C discharges through a loop formed by the control switch FV, a secondary coil L2 of the saturation transformer T, a primary coil L1 of the saturation transformer T and an arc gap of the mechanical switch S, so that the current is of the mechanical switch S is reduced, the current ic of the capacitor C is increased, and current transfer is realized;
3) the equivalent excitation magnetic potential of the saturation transformer T is N1-N2 ic, the is larger and the ic is smaller in the stage of starting current transfer, the equivalent excitation magnetic potential is a positive value and has a larger value, and the saturation transformer T does not obviously exit from a deep saturation state;
4) with the progress of the current transfer process, the equivalent excitation magnetic potential of the saturation transformer T is gradually reduced from a positive value and becomes a negative value before the current of the mechanical switch S passes zero, and due to the hysteresis characteristic, the inductance values of the primary coil L1 and the secondary coil L2 of the saturation transformer T are still smaller when the equivalent excitation magnetic potential is zero, so that the current transfer process is not obviously slowed down;
5) when the equivalent excitation magnetic potential of the saturation transformer T is reduced to a negative value, the inductance values of the primary coil L1 and the secondary coil L2 of the saturation transformer T are rapidly increased near the coercive current-I1, the current change rate near the zero crossing of the current of the mechanical switch S is greatly reduced, and therefore the breaking reliability of the mechanical switch S is improved.
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Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3624411A (en) * | 1970-03-23 | 1971-11-30 | Honeywell Inc | Switching circuit for delayed phase firing of a power switch |
| CN101192482A (en) * | 2006-11-28 | 2008-06-04 | 三菱电机株式会社 | Switch controlling device |
| CN203278226U (en) * | 2013-05-30 | 2013-11-06 | 西安科技大学 | Capacitance regulating type automatic tuning arc extinguishing device |
| CN104158171A (en) * | 2014-08-18 | 2014-11-19 | 国家电网公司 | High voltage direct current circuit breaker topology circuit |
| WO2015110142A1 (en) * | 2014-01-21 | 2015-07-30 | Siemens Aktiengesellschaft | Device for switching a direct current |
| CN106786348A (en) * | 2016-11-11 | 2017-05-31 | 西安交通大学 | One kind is based on bridge-type sensing transfer dc circuit breaker and its application method |
| CN107154322A (en) * | 2017-04-10 | 2017-09-12 | 华北电力大学 | A kind of low-loss hybrid high voltage DC breaker |
| CN207441525U (en) * | 2017-11-21 | 2018-06-01 | 武汉船用电力推进装置研究所（中国船舶重工集团公司第七一二研究所） | A kind of manual zero passage technology main circuit topological structure |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE19944733B4 (en) * | 1999-09-17 | 2007-01-04 | Siemens Ag | Device for controlling at least one capacitive actuator |
| KR100355962B1 (en) * | 2000-04-25 | 2002-10-11 | 삼성전기주식회사 | High efficiency converter for zero voltage switching |
-
2017
- 2017-11-21 CN CN201711167842.6A patent/CN107833772B/en active Active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3624411A (en) * | 1970-03-23 | 1971-11-30 | Honeywell Inc | Switching circuit for delayed phase firing of a power switch |
| CN101192482A (en) * | 2006-11-28 | 2008-06-04 | 三菱电机株式会社 | Switch controlling device |
| CN203278226U (en) * | 2013-05-30 | 2013-11-06 | 西安科技大学 | Capacitance regulating type automatic tuning arc extinguishing device |
| WO2015110142A1 (en) * | 2014-01-21 | 2015-07-30 | Siemens Aktiengesellschaft | Device for switching a direct current |
| CN104158171A (en) * | 2014-08-18 | 2014-11-19 | 国家电网公司 | High voltage direct current circuit breaker topology circuit |
| CN106786348A (en) * | 2016-11-11 | 2017-05-31 | 西安交通大学 | One kind is based on bridge-type sensing transfer dc circuit breaker and its application method |
| CN107154322A (en) * | 2017-04-10 | 2017-09-12 | 华北电力大学 | A kind of low-loss hybrid high voltage DC breaker |
| CN207441525U (en) * | 2017-11-21 | 2018-06-01 | 武汉船用电力推进装置研究所（中国船舶重工集团公司第七一二研究所） | A kind of manual zero passage technology main circuit topological structure |
Non-Patent Citations (1)
| Title |
|---|
| 一种适于快速高压直流断路器的过零振荡电路;李黎等;《中国电机工程学报》;20160605;第36卷(第11期);全文 * |
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