GB2501107A - AC-DC converter device comprising soft start and over-voltage protection system - Google Patents

AC-DC converter device comprising soft start and over-voltage protection system Download PDF

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Publication number
GB2501107A
GB2501107A GB1206477.0A GB201206477A GB2501107A GB 2501107 A GB2501107 A GB 2501107A GB 201206477 A GB201206477 A GB 201206477A GB 2501107 A GB2501107 A GB 2501107A
Authority
GB
United Kingdom
Prior art keywords
tss
converter
main switch
control circuit
soft start
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
GB1206477.0A
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GB201206477D0 (en
Inventor
Erik Myhre
Thomas Andre Olsen
Jan Tore Brastad
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Delta Electronics Norway AS
Original Assignee
Eltek AS
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Eltek AS filed Critical Eltek AS
Priority to GB1206477.0A priority Critical patent/GB2501107A/en
Publication of GB201206477D0 publication Critical patent/GB201206477D0/en
Publication of GB2501107A publication Critical patent/GB2501107A/en
Withdrawn legal-status Critical Current

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Classifications

    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
    • H02H3/00—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection
    • H02H3/20—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection responsive to excess voltage
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
    • H02H9/00—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection
    • H02H9/001—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection limiting speed of change of electric quantities, e.g. soft switching on or off
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
    • H02H9/00—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection
    • H02H9/02—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection responsive to excess current
    • H02H9/025—Current limitation using field effect transistors
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
    • H02H9/00—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection
    • H02H9/02—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection responsive to excess current
    • H02H9/026—Current limitation using PTC resistors, i.e. resistors with a large positive temperature coefficient
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M1/00—Details of apparatus for conversion
    • H02M1/36—Means for starting or stopping converters
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
    • H02H7/00—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions
    • H02H7/10—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for converters; for rectifiers
    • H02H7/12—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for converters; for rectifiers for static converters or rectifiers
    • H02H7/122—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for converters; for rectifiers for static converters or rectifiers for inverters, i.e. dc/ac converters
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
    • H02H9/00—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection
    • H02H9/005—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection avoiding undesired transient conditions
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M1/00—Details of apparatus for conversion
    • H02M1/0067—Converter structures employing plural converter units, other than for parallel operation of the units on a single load
    • H02M1/007—Plural converter units in cascade

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Dc-Dc Converters (AREA)
  • Rectifiers (AREA)

Abstract

The invention relates to a soft start and overvoltage protection system (10) comprising first and second input terminals for connection to an AC input and first and second output terminals connected to a boost converter (3). The second input terminal is connected to the second output terminal. A main switch (MS) is connected between the first input terminal and the first output terminal. A control circuit is provided for controlling the main switch (MS). The main switch may be a transistor device controlled as an ohmic resistance for a predetermined amount of time after voltage supply is turned on. The main switch may be a relay and a variable resistor (RC in figure 3), which may be a transistor or a positive temperature coefficient resistor, may be connected between the first input and first output terminal. The boost converter may be connected to a DC-DC converter (4) both of which may be controlled by the controller. A capacitor (C) may be connected between the outputs of the boost converter. A flyback converter (5) maybe connected between the first boost output terminal and the control terminal.

Description

AC-DC converter device comprising soft start and overvoJtage protection system
FIELD OF THE INVENTION
The present invention relates to AC-DC converter device comprising a soft start und overvoltage protection system.
BACKGROUND OF TIlE INVENTION
Several types of converters are known for use in power supply systems, where there is a need to convert an AC power to a controlled DC power. The AC power will usually be supplied from an AC power source, such as the mains. The DC power is supplied to equipment such as telecommunication equipment, broa.d band data communication equipment (GSM/TJMTS base stations etc), military equipment, medical equipment etc. There arc several requirements lin such power supply systems. First of all, the efficiency should he high, i.e the losses should he low. The power supply system described in WO 2009/028954 and WO 2009/058024 has an efficiency of ca 96% and is marketed and sold by Eltek Valere under the name FlatPack 2 HE. The power supply system provided as a unit for insertion into a rack. The unit has an height of 113 (the standard height of one shelf in a rack, corresponding to 44,5 mm), a length of 328 mm and a width of 109 mm so that four such units may be provided next to each other in a 19" rack. The unit may deliver a power of 2kW or 3kW at -48V DC.
The object of the next generation power supply is to provide a smaller unit having substantially the same power as the above power supply system and with a relatively high efficiency. More specifically, the new unit should be IU high. The length should be 220 mm so that the unit and the rack may be provided in a 30 cm power cabinet. In addition, the width should 72 mm in order to provide that six such units may be provided next to each other in a 19" rack. The unit should he able to supply a power of 2 -3000 W at -48V DC. Hence, the available volume for the components is reduced by approximately 55 %.
Another important oh] ect of the next generation power supply system is to reduce costs. One contribution to cost reduction is the reduced size. AnoLher contribution to cost reduction is to usc cheaper electronic components such as processor units etc. However, such electronic components are simpler, and consequently, effort must be put into using the electronic components smarter. One way of achieving this is to reduce the number of calculations needed for controlling the power supply system The power supply system comprises a fan for blowing air through the unit. The fan is normally located on the front side of the unit and blows air out through the rear side of the unit. The increased power density (power per volume unit) of the unit makes it difficult to achieve a satisfying air flow through the unit.
A soft start system is used in electrical circuits for reducing excess current during initial power-tip.
An overvoltage protection system. is used in electrical circuits to protect high voltage sensitive components from temporary overvoltage occurring in the AC mains, for example due to sudden load disconnection elsewhere in the AC mains.
An AC-DC converter device 1 according to the ahovementioned prior art is shown in fig. 1. The AC-DC converter device 1 comprises an EMI filter 2, a boost converter 3, and a DC-DC converter 4 connected between the AC input and the DC output. The boost converter 3 and the DC-DC converter are considered known for a person skilled in the art for example from the two publications cited above. The terminals between. the boost converter 3 and the DC-DC converter are denoted with Thl and Tb2 as shown in fig. 1.
In addition, the AC-DC converter device 1 comprises a soil starting system 10 connected between the EMI filter 2 and the boost converter 3. The soft starting system 10 has first and second input terminals Iss_ini, Tss_in2 and first and second output terminals Tss outi, Tss out2, wherc the second input terminal Tssin2 is connected to the second output terminal Tss_out2, The soil starting system 1 0 comprises a main relay kM connected between the first input terminal Tss_ini and the first output terminal I'ss_outl. Moreover, the soft startin.g system 1 0 comprises an auxiliary relay Raux and a negative temperature coefficient resistor or NTC-resistor, denoted NTC in the drawings, which are connected in series between the first input terminal Tss ml and the first output terminal Tss outl. The NTC-resistor has a resistance which decreases with an increase in temperature.
A capacitor C is connected between the boost converter 3 and the DC-DC converter 4. i.e. between terminals Tbl and Tb2, as shown iii fig. 1. The capacitor C may be considered to be a part of the boost converter 3 and may be referred to as a boost capacitor.
Moreovcr, the AC-DC converter system I comprises a. flyback converter 5 connected between the first boost termina.l Thi and a. DC control terminal Teontrol, for converting the boost voltage Yb to a DC control voltage. The DC control voltage is supplying a DC voltage to a digital signal processor which is controlling the main relay RM, the auxiliary relay Raux and the switch S of the flyback converter 5.
When the system 1 in fig. I is plugged into the AC mains, a soft start is ensured by having the default state of the auxiliary relay Raux to be ON (i.e. conducting) (and the main relay RM to be OFF). hence, the capacitor C is charged by the AC mains through the NTC-resistor NTC. In the beginning, the NTC-resistor is cold and has a relatively high resistance.
After a short while, the voltage over the flyback converter 3 will be sufficient to power the digital signal processor.
Then, the main relay RiM is turned ON and is carrying the main current from the AC mains to the AC-DC converter.
Jf the voltage level of the AC mains gets higher then a threshold value, the main relay RM and the auxiliary relay are turned OFF (ie, non-conducting) and hence, voltage-sensitive components are protected. The flyback converter is supplied with energy stored in the capacitor C and the digital signal processor is still powered.
If the voltage over the capacitor C drops below a certain threshold level, the auxiliary relay Raux is turned ON for a short while to charge the capacitors through the NTC-resistor in order to provide energy Eu (lie digital signal rrocessor.
One disadvantage of the above is that two relays are needed for the above soft start H 20 and overvoltage protection system. l'hcse relays occupy a lot of space inside the power supply unit and also obstruct the cooling air flow through the unit.
Another disadvantage is that if there is a short circuit in the boost converter 3 or in the DC-DC converter 4, the NTC-resistor often gets overheated and damaged.
The object of the invention is to reduce the number of components while still achieving soft start capabilities and overvoltage protection of the AC-DC converter system. This especially relates to controllable components, since this also will reduce the complexity of the control system.
The object of the invcntion is to solving the above problems in order to provide a H power supply unit with the specifications mentioned above.
SUMMARY OF'lHE INVENTION
The present invention relates to a soi' start and overvoltage protection system comprising: -first and second input terminals for connection to an AC input; -first and second output terminals connected to a boost converter, where the second input terminal is connected to the second output terminal; -a main switch connected between the first input terminal and the first output terminal; -a control circuit for controlling the main switch.
In one aspect, the main switch is a transistor device where a gate terminal of the transistor device is connected to the control circuit; and the control circuit is configured to control the main switch as a an ohmic resistance in a predctermined time period alter a voltage has been detected on the first and second input terminals.
In one aspect, the main switch is a relay controlled by the control circuit; a variable resistor is connected between the first input terminal and the first output terminal; and the control circuit is configured to turn the main switch off in a predetermined time period after a voltage has been detected on the first and second input terminals.
In one aspect, the variable resistor is a transistor device where a gate terminal of ti-ic transistor device is connected to the control circuit; and the control circuit is configured to control the variable resistor as a an ohmic resistance in a predetermined time period after a voltage has been detected on the first and second input terminals.
In one aspect, the variable resistor is a positive temperature coefficient resistor.
In one aspect, the control circuit is configured to turn the main switch off when a voltage Ym between the first and second input terminals is above an overvoltage threshold value.
In one aspect, the control circuit is configured to turn the main switch on again when: -a capacitor voltage is below a predetermined capacitor value, and -the instantaneous voltage Ym between the first and second input terminals is below the overvoltage threshold value.
In one aspect, the main switch comprises contacts made of AGSnO or AgSnO2.
In one aspect, the system is providing soft start and overvoltage protection for an AC-DC converter.
* The invention also relates to an AC-DC convener device comprising: -a boost converter comprising input terminals and output terminals; -a DC-DC converter comprising input terminals connected to the output terminals of the boost converter and output ternilnais for connection to a load; -a soft start and overvoltage protection system according to the above invention: where the output tenninals of the system is coniiected to tile input terminals of the S boost converter; and where the control circuit of the system is also controlling the boost converter and the DC-DC converter.
In one aspect, the AC-DC converter device is comprising a boost capacitor connected between the first and second output boost terminals.
In one aspect, the AC-DC converter device is comprising a flyhack convertcr connected between the first boost output terminal and a control terminal.
DETAILED DESCRIPTION
Embodiments of the invention will now he described in detail with reference to the enclosed drawings, where: Fig: 1 iiJustrates a prior art. power supply system; H 15 Fig. 2 illustrates a first embodiment of a soft start and overvoltage protection H. system in a power supply system; Fig. 3 illustrates a second embodiment of a soft start and overvoltage protection system in a power supply system; Fig. 4 illustrates a second embodiment of a soft start and overvoltage protection system in a power supply system.
The prior art of fig. 1 is considered to be described in the introduction above. It is now referred to fig. 2 -4. Here, it is shown a soft start and overvoltage protection H system 10. The soft start and overvoltage protection serves two functions, soft starting and overvoltage protection, as defined in the above-mentioned description.
In the following, the system 10 is providing soft start and overvoltage protection for an AC-DC converter.
The system 10 comprises first and second input terminals Tss_inl, Tss in2 for connection to an AC input, either directly or via an EMI-filter 2 andlor other electric components.
The system 1 0 further comprises first and second output terminals Tssoutl, Tssout2 connected to a boost converter 3. The boost converter 3 may be a bridgelcss boost converter or a boost convcrter with a diodc bridge in. front. The second input terminal Tss_in2 is connected to the second output terminal Tss_out2.
The system 10 comprises a main switch MS connected between the first input terminal Tss ni and the first output terminal Tssout2.
The system 10 further comprises a control circuit (not shot) for controlling the main switch MS.
It is now referred to fig. 2. Here, the main switcit MS is a transistor device where a gate terminal of the transistor device is connected to the control circuit.
The overvoltage protection function is achieved by configuring the control circuit to turn the main switch MS off when a voltage Vm bctwecn the first and second input terminals Tss in!, Tss_in2 is above an overvoltage threshold value. The soft start function is achieved by configuring the control circuit to control the main switch MS as an ohmic resistance in a predetermined time period after a voltage has been detected on the first and second input terminals Tss ml, Tss_in2. For example, the main switch may initially be turned oft and then the resistance of the transistor device is gradually reduced during the predetermined time period. After the time period, the main switch MS is turned rully on. Examples of transistor devices which may be used for such a purpose are high voltage n-channel mosfets, p-channel mosfets. npn bipolar transistors and pnp bipolar transistors.
It is now referred to fig. 3 and 4. Here the main switch MS is a relay controlled by the control circuit. In addition, the system 10 comprises a variable resistor RC connected between the first input tenninal Iss ml and the first output terminal Tssout2. Ihe soft start function is achieved by configuring the control circuit to turn the main switch. MS off in a prcdetermined time period after a. voltage has been detected on the first and second input terminals Tss ml, Tss in2.
In fig. 3. the variable resistor RC is a transistor device where a gate terminal of the transistor device is connected to the control circuit. The soft start function is achieved by configuring the transistor device as an ohmic resistance in a predetermined time period after a voltage has been detected on the first and second input terminals Tss_in 1, Tss in2. The above-mentioned examples of transistor devices may he used the overvoltage protection function of the system 10 in fig. 3 is achieved by configuring the control circuit to control to turn the main switch MS off when a.
voltage Ym between the first and second input terminals Tss_inl, Tss in2 is above an overvoltage threshold value. At the same time, the control circuit is configured to turn the transistor device RC off, alternatively to control the transistor device so that its resistance is increased considerably and thereby reducing the voltage between the output terminals Tss outi, Tss out2 of the system 10.
In fig. 4, the variable resistor RU is a positive temperature coefficient resistor PLC (PTC resistor). The resistance of the FTC resistor is increasing as its temperature is increasing. The soil start function is achieved by configuring the control circuit to turn the main switch MS off in a predetermined time period afl.er a voltage has been detected on the first and second input terminals Tss ml, Tss_in2. Initially, the PTC H resistor is cold, and the resistance is ow. Hence, relatively large current will go through the PTC resistor, thereby hicreasing the temperature of the PTC resistor 1 0 fast. Accordingly its resistance increases fast, thereby providing a soft start.
The overvoltage protection function ot'the system lOin fig. 4 is achieved by configuring the control circuit to control to turn the main switch MS oil when a voltage Ym between the first and second input terminals Tss ml, Tss in2 is above an overvoltage threshold value. During normal operation, the PTC resistor has been heated by surrounding electric components, and hence has a relatively large resistance. Hence, the output terminals Tss outi, Tss_out2 of the system 10 will be protected by turning the main switch off.
The power to the control circuit is supplied via the terminal Icontrol in fig. 2 -4.
J-Tere it is apparcnt that the control terminal Tcontrol is connected to a boost capacitor C connected to the output terminals Tbl, Tb2 of the boost converter 3 via a flyback converter 5. When an overvoltage situation occurs, no current is supplied via the system 10, and hence, the control system is supplied with energy stored in the boost capacitor C. However, if the ovcrvoltagc situation is lasting for a longer period of time. i.e. during a period where the average voltage Vrn between the first and second input terminals Tss ml, Tss in2 is above an overvoltage threshold value, the control circuit itself may need power supply since the capacitor voltage Vb is below a predetermined capacitor value.
Hence, the control system of the soil start and overvoltage protection system 10 may be configured to, during a period where the average voltage Vm between the first and second input terminals Tss_inl, Tss_in2 is above an overvoltage threshold value, to turn the main switch MS on again when the following criteria is met: -the capacitor voltage (Vb) is below a predetermined capacitor value, and -the instantaneous voltage Vm between the first and second input terminals Iss_ini, Tss n2 is below the overvoltage threshold value.
The above described system 10 is requires to operate fast. It is therefore prcferred that the main switch MS comprises contacts made of AGSnO or AgSnO2.
The present invention also relates to an AC-DC converter device 1. The AC-DC converter I is comprising the following; -a boost converter 3 comprising input terminals and output terminals fbi, l'b2; -a DC-DC converter 4 comprising input terminals connected to the output terminals Tb 1, Tb2 of the boost converter 3 and output terminals Tdcl, Tdc2 for connection to a load, and -a soft start and overvoltage protection system 10 as described above, where the output terminals Tss outi, Tss_out2 of the system 10 is connected to the input terminals of the boost convcrter 3; and where the control cIrcuit of thc system lOis also controlling the boost converter 3 and the DC-DC converter 4. The AC-DC converter device I further comprises a boost capacitor C connected between the first and second output boost terminals Fbi, 1'b2.
Moreover, the AC-DC converter device 1 may further comprise a flyback converter connected between the first boost output terminal Thi and a control terminal Tcontrol.

Claims (12)

  1. CLAIMS1. Soft start and overvoltage protection system (10) comprising: -first and second input terminals (Tss ml, Tss_in2) for connection to an AC input; -first and second output terminals (Tss out!, I'ss_out2) connected to a boost converter (3), where the second input terminal (Tss in2) is connected to the second output terminal (Tssout2); -a main switch (MS) connected between the first input terminal (Tss_in 1) and the first output terminal (Tss out2); -a control circuit for controlling the main switch (MS).
  2. 2. Soft start and overvoltage protection system (10) according to claim 1, where: -the main switch (MS) is a transistor device where a gate terminal of the transistor device is connected to the control circuit; -the control circuit is configured to control the main switch (MS) as a an ohmic resistance in a predetermined time period after a voltage has been detected on the first and second input terminals (Tss i, Tss_in2).
  3. 3. Soft start and overvoltage protection system (10) according to claim 1, where: -the main switch (MS) is a relay controlled by the control circuit; -a variable resistor (RC) is connected between the first input terminal (Tss ml) and the first output terminal (Tss out2); -the control circuit is configured to turn the main switch (MS) off in a predetermined time period after a voltage has been dctcctcd on the lust and second input terminals (Tss_inl, Tss_in2).
  4. 4. Soft start and overvoltage protection systcm (10) according to claim 3, where: -the variable resistor (RC) is a transistor device where a gate terminal of the transistor device is connected to the control circuit; -the control circuit is configured to control the variable resistor (RC) as a an ohmic resistance in a predetermined time period after a voltage has been dctccted on the first and second input terminals (Iss_ini, Tss_in2).
  5. 5. Soft start and overvoltage protection system (10) according to claim 3, where: -the variable resistor (RC) is a positive temperature coefficient resistor (PTC).
  6. 6. Soft start and overvoltage protection system (10) according to any one of claims I 5, where the control circuit is configured to turn the main switch (MS) off when a voltage Vm between the first and second input terminals (Tss i, Tss in2) is above an overvoltage threshold value.
  7. 7. SoFt start and overvoltage protection system (10) according to claim 6, where: -the control circuit is configured to turn the main switch (MS) on again when: -a capacitor voltage (Vb) is below a predetermined capacitor value, and -the instantaneous voltage Vm between the first and second input terminals (Tss_inl, Tss_in2) is below the overvoltage threshold value.
  8. 8. Soft start and overvoltage protection system (10) according to any one of the above claims, where the main switch (MS) comprises contacts made of AGSnO or AgSnO2.
  9. 9. Soft start and overvoltage protection system (10) according to any one of the above claims, where the system (10) is providing soft start and overvoltage protection for an AC-DC converter.
  10. 10. AC-DC converter device (I) comprising: -a boost converter (3) comprising input terminals and output terminals (Tbl, Tb2); -a DC-DC converter (4) comprising input terminals connected to the output terminals (Tbl, Tb2) of the boost converter (3) and output terminals (Tdcl, Tde2) for connection to a load; -a suit start and overvoltage protection system (10) according to any one of claims 1 -9; where the output terminais (Tss_outl, Tss_out2) of the system (10) is connected to the input terminals of the boost converter (3); and where the control circuit of the system (10) is also confrolling the boost converter (3) and the DC-DC converter (4).
  11. 11. AC-DC converter device (1) according to claim 10, further comprising a boost capacitor (C) connected between the first and second output boost terminals (Tb 1, Yh2).
  12. 12. AC-DC converter device (1) according to claim 10, further comprising a Ilybacic converter (5) connected between the first boost output terminal (Tbl) and a control terminal (Teontrol).
GB1206477.0A 2012-04-12 2012-04-12 AC-DC converter device comprising soft start and over-voltage protection system Withdrawn GB2501107A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB1206477.0A GB2501107A (en) 2012-04-12 2012-04-12 AC-DC converter device comprising soft start and over-voltage protection system

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Application Number Priority Date Filing Date Title
GB1206477.0A GB2501107A (en) 2012-04-12 2012-04-12 AC-DC converter device comprising soft start and over-voltage protection system

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GB201206477D0 GB201206477D0 (en) 2012-05-30
GB2501107A true GB2501107A (en) 2013-10-16

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20130234686A1 (en) * 2010-03-23 2013-09-12 Northrop Grumman Systems Corporation System and method for providing a high efficiency bypass circuit for multi-stage dc-dc converters used in battery powered systems
WO2019029140A1 (en) * 2017-08-08 2019-02-14 深圳光峰科技股份有限公司 Switching power supply and projector
EP4239872A4 (en) * 2020-11-12 2024-07-03 Huawei Digital Power Tech Co Ltd Power converter, and protection method and system

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2320145A (en) * 1996-12-06 1998-06-10 Switched Reluctance Drives Ltd Current Limiter
JP2007267473A (en) * 2006-03-28 2007-10-11 Matsushita Electric Ind Co Ltd Inrush current prevention circuit

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2320145A (en) * 1996-12-06 1998-06-10 Switched Reluctance Drives Ltd Current Limiter
JP2007267473A (en) * 2006-03-28 2007-10-11 Matsushita Electric Ind Co Ltd Inrush current prevention circuit

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20130234686A1 (en) * 2010-03-23 2013-09-12 Northrop Grumman Systems Corporation System and method for providing a high efficiency bypass circuit for multi-stage dc-dc converters used in battery powered systems
US8971073B2 (en) * 2010-03-23 2015-03-03 Northrop Grumman Systems Corporation System and method for providing a high efficiency bypass circuit for multi-stage DC-DC converters used in battery powered systems
WO2019029140A1 (en) * 2017-08-08 2019-02-14 深圳光峰科技股份有限公司 Switching power supply and projector
EP4239872A4 (en) * 2020-11-12 2024-07-03 Huawei Digital Power Tech Co Ltd Power converter, and protection method and system

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