RU184526U1 - Offline power supply - Google Patents

Offline power supply Download PDF

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RU184526U1
RU184526U1 RU2018103240U RU2018103240U RU184526U1 RU 184526 U1 RU184526 U1 RU 184526U1 RU 2018103240 U RU2018103240 U RU 2018103240U RU 2018103240 U RU2018103240 U RU 2018103240U RU 184526 U1 RU184526 U1 RU 184526U1
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Russia
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phase
voltage
terminals
connected
converter
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RU2018103240U
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Russian (ru)
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Михаил Анатольевич Киселев
Ярослав Владимирович Морошкин
Станислав Борисович Резников
Игорь Александрович Харченко
Валерий Николаевич Смирнов
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Федеральное государственное унитарное предприятие "Государственный научно-исследовательский институт авиационных систем" (ФГУП "ГосНИИАС")
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    • GPHYSICS
    • G05CONTROLLING; REGULATING
    • G05FSYSTEMS FOR REGULATING ELECTRIC OR MAGNETIC VARIABLES
    • G05F1/00Automatic systems in which deviations of an electric quantity from one or more predetermined values are detected at the output of the system and fed back to a device within the system to restore the detected quantity to its predetermined value or values, i.e. retroactive systems
    • G05F1/66Regulating electric power
    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02PCONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
    • H02P9/00Arrangements for controlling electric generators for the purpose of obtaining a desired output
    • H02P9/14Arrangements for controlling electric generators for the purpose of obtaining a desired output by variation of field
    • H02P9/26Arrangements for controlling electric generators for the purpose of obtaining a desired output by variation of field using discharge tubes or semiconductor devices
    • H02P9/30Arrangements for controlling electric generators for the purpose of obtaining a desired output by variation of field using discharge tubes or semiconductor devices using semiconductor devices

Abstract

The utility model relates to electrical engineering and to pulsed power electronics and is intended for use as trunk channels of an airborne combined electric power complex with a backup-battery uninterruptible power supply.
The technical result of the proposed utility model is to improve reliability by increasing the power factor at the output of the starter generator and its efficiency, as well as by reducing noise emissions and improving mass-energy characteristics.
The indicated results are ensured due to the fact that an autonomous power supply containing a three-phase electric machine starter-generator 1 of alternating current with unstable parameters is connected to distribution busbars 2 of alternating voltage with unstable parameters and to the first reversible rectifier-inverter converter 3 with an input power factor corrector and with an output differential link of 4 constant increased voltages for parallel connection of similar sources and naib more powerful loads, a sinusoidal voltage inverter 5, AC distribution busbars 6 with stable parameters, a reversible pulse converter 7, DC distribution busbars 8 for connecting the battery and associated loads, and a control unit 9 with feedback circuits 10, 11 and with control conclusions 12, introduced distribution bus 13 of alternating voltage with a stable amplitude for connecting powerful loads that are not critical to frequency stability, and the first inductance an o-capacitive filter 14, as well as a second reversible rectifier-inverter converter 15, the first converter consisting of a second inductive-capacitive filter 16, two groups of diode-key racks 17 and valve-condenser racks 18, three-phase reactors 19-20 and equalizer divider voltage 21, and also due to the fact that a three-phase contactor 24 is connected to it, connected to the output terminals of the chokes of the second filter, which together with the phase reactors are made with phase-common magnetic circuits, and the bridges of the second STUDIO and equalizing voltage divider formed by anti-parallel diode in the branches of the key shoulders.

Description

The utility model relates to electrical engineering and to pulsed power electronics and is intended for use as trunk channels of an airborne combined electric power complex with a backup-battery uninterruptible power supply.

Known airborne autonomous power supply (analogue), containing a three-phase magnetoelectric electric starter-generator (without a constant speed drive) with permanent magnets on the rotor, and with an output voltage unstable in frequency and amplitude, an emergency switch, a reversible rectifier-inverter converter connected to the output to the distribution subsystem of direct increased voltage with a grounded "minus" and two split buses with asynchronously floating (having regulating alternate interruptions or “dips”) with “positive” potentials - for ensuring arc-free switching (SB Reznikov. Aircraft power supply system of quasi-constant increased voltage. // Aviation Instrument Engineering, 2004, No. 4, pp. 62-67, pp. .63, Fig. 1 and p. 65, Fig. 3a). The significant advantages of this device, in addition to eliminating the constant speed hydraulic or pneumatic drive, which has low reliability and efficiency and high operating costs, include the use of the so-called DC link (270, 540 or 750 V), which allows combining (in parallel) autonomous sources power supply to increase the total installed capacity and, accordingly, to preserve the quality of electricity in transient and emergency conditions.

The disadvantages of this known device (analogue) include: the difficulty of implementing arc-free switching in a distribution system (cable splitting, introduction of summing diodes for each load, doubling the number of contactors) and narrow functionality due to the inability to ensure the recovery of electricity from the load to the source and use in generator starter mode, as well as increased noise emissions.

Of the known devices, the closest to the proposed one in technical essence is an autonomous power source (prototype) containing an electric machine asynchronous starter-generator with a three-phase alternating voltage with an unstable frequency (360 ... 800 Hz), but with a stable amplitude

Figure 00000001
and an auxiliary asynchronous starter-generator driven by an auxiliary power unit having stabilized frequency and amplitude parameters (400 Hz,
Figure 00000002
), with self-excitation along the anchor circuits through an adjustable inverter of a sinusoidal voltage, having circuits connecting to the main generator. In addition, the source contains a reversible rectifier-inverter converter with an input power factor corrector and an output differential link of constant increased voltages (0 ± 135 V or 0 ± 270 V) for connecting similar parts of other sources and the most powerful DC voltage loads in parallel, as well as a reversible a pulse converter connected between the differential link and DC busbars with a rechargeable battery connected to them (Reznikov SB, Bocharov VV, Kharchenko IA E electromagnetic and electric compatibility of power supply systems and secondary power sources of fully electrified aircraft / Edited by SB Reznikov. / M .: MAI Publishing House, 2014,160 s, p. 30, Fig. 1.2.2)

The disadvantages of this autonomous power source (prototype) include: narrow functionality due to the inability to use a permanent magnet magnetoelectric machine with permanent magnets on the rotor with improved mass-energy and reliability characteristics as a main starter-generator and due to the inability to supply high-power loads with variable stabilized by amplitude voltage, arbitrary frequency, bypassing the inverter of a sinusoidal voltage with a limited installation oschnostyu and low power factor at the output of the starter-generator, its efficiency is low and large pomehoizlucheniya due to high ripple currents and voltages in the anchor chain.

The technical result of the proposed utility model is to improve reliability by increasing the power factor at the output of the starter generator and its efficiency, as well as by reducing noise due to the reduction of high-frequency ripple currents and voltages in the armature circuit, and while improving the mass-energy characteristics due to the possibility of power supply loads of variable amplitude-stabilized voltage of arbitrary frequency bypassing the inverter of a sinusoidal voltage with limited installation power.

The indicated result is ensured due to the fact that an autonomous power supply containing a three-phase electric machine starter-alternator with unstable parameters is connected to the distribution busbars of the alternating voltage with unstable parameters and to the first reversible rectifier-inverter converter with an input power factor corrector and an output differential a link of constant increased voltages for parallel connection of similar sources and the most sensible loads, a sinusoidal voltage inverter, stable distribution busbars of alternating voltage, a reversible pulse converter, distribution buses of constant low voltage for connecting the battery and the corresponding loads and a control unit with feedback circuits and with control outputs, introduced distribution busbars of stable voltage amplitude for connecting powerful loads that are not critical to frequency stability, and the first inductive-capacitive filter p, as well as a second reversible rectifier-inverter converter, the first converter CONSISTING of a second inductance-capacitive filter, two groups of diode-key racks and valve-capacitor racks, three-phase reactors and an equalizing voltage divider, as well as due to the fact that a three-phase contactor connected to the output terminals of the chokes of the second filter, which together with the phase reactors are COMPLETE with phase-common magnetic circuits, and the bridges of the second converter and equalizer divider voltages are COMPLETE with counter-parallel diode-key branches in the shoulders.

Experimental studies of the laboratory layout and computer simulation of the proposed autonomous power source have confirmed its efficiency and feasibility of wide industrial use.

In FIG. 1, a structural diagram of a power circuit is shown; FIG. 2 - control channels of the proposed autonomous power source.

The self-contained power supply contains a three-phase electromachine starter-generator 1 of alternating current with unstable parameters, connected by its anchor winding to distribution busbars 2 of alternating voltage with unstable parameters for connecting loads that are not critical to the quality of electricity and to the AC terminals of the first reversible rectifier-inverter converter 3 s input power factor corrector and with output differential outputs connected to the differential link Well, 4 constant increased voltages with a grounded medium potential bus for parallel connection of similar sources and the most powerful loads. The device also contains a sinusoidal voltage inverter 5, connected by an input to the specified link, and by the output to distribution buses 6 of an alternating three-phase voltage with stable frequency and amplitude parameters, a reversible pulse converter 7, connected between the specified link and distribution buses 8 of a constant low voltage for connecting back-up -a battery and associated loads, as well as a control unit 9 with circuits 10, 11 feedback on currents and voltages and with pulse-modulator and relay-signal outputs 12 for controlling these converters. In addition to the above, the device contains distribution buses 13 of a three-phase AC voltage with a stable amplitude for connecting powerful loads of AC voltage that are not critical to frequency stability, and a first three-phase inductive-capacitive filter 14 of a low frequency connected by an output to these buses, as well as a second reversible rectifier-inverter a converter 15 made according to a three-phase bridge circuit. The first reversible rectifier-inverter converter consists of an input second three-phase inductive-capacitive filter 16 with additional outputs connected in series, two parallel-split three-phase groups of grounding diode-key racks 17, two parallel-split three-phase groups of grounding valve-condenser racks 18, three two-section phase reactors 19-20 and equalizing voltage divider 21, made according to the scheme of a three-phase bridge, shunted at the exit extreme conclusions dvuhkondensatornoy a filter rack 22-23.

The output chokes of the second inductance-capacitive filter 16 and phase reactors 19, 20 of the first reversible rectifier-inverter converter 3 are made with phase-common magnetic circuits, and the pairs of sections of each of the phase reactors are connected in opposite directions (as indicated in the drawing by the designations of their windings).

Three-phase bridges of the reversible second rectifier-inverter converter 15 and equalizing voltage divider 21 are made with counter-parallel diode-key branches in the bridge arms.

The differential output terminals of the first reversible rectifier-inverter converter 3 are connected directly to the differential link 4 of constant high voltage with a grounded mid-voltage bus, and also connected via a sine wave inverter 5 to the distribution busbars 6 of an alternating three-phase voltage with stable frequency and amplitude parameters and through a reversible pulse converter 7 - to the distribution busbars 8 constant low voltage.

The second reversible rectifier-inverter converter 15 is connected to the additional terminals of the second three-phase inductance-capacitive filter 16 of the first converter by its AC terminals, and to the extreme ends of the two-capacitor filter rack 22-23, which shunts the 4 DC link with its own DC terminals.

Key transistors are used as electronic keys of the listed converters, and conventional (single-operation) thyristors controlled from relay-signal outputs 12 of the control unit 9 are used as controlled valves of the valve-condenser racks 18.

Autonomous power source operates as follows. Distribution buses 2 connect AC loads that are not critical to the quality of the electric power (for example, heating devices, anti-icing-thermal, lighting and other equipment); to distribution buses 13 - the most powerful AC loads, non-critical to the frequency (for example, electro-pulse anti-icing system and the above); to distribution buses 6 (for example, with a traditional three-phase airport voltage

Figure 00000003
, 400 Hz) - loads critical to the quality of electricity (for example, airborne navigation and control equipment, including computer and computer, microprocessors, controllers, etc.), and to the distribution buses 8 - backup battery, low-voltage lighting, navigation and signal and other vital equipment that defines “survivability”, “hot standby” and “uninterrupted power”. To the differential link 4 of constant increased voltage connect similar links of other main channels and the most powerful loads of constant increased voltages with the possibility of energy recovery (for example, powerful electric drive motors with regenerative braking, etc.).

On the pulse-modulator and relay-signal terminals 12 of the control unit 9, high-frequency rectangular pulse-width modulated pulses and low-frequency bursts of short-term pulses are synchronized with the half-periods of the phase voltage of the starter generator 1.

The first reversible rectifier-inverter Converter 3 operates as follows. In the direct transformation of the contactor 24 shown razomknut.Na arbitrary pulse-width modulation (T PWM) in any of the phase conversion circuits in any half cycle of the phase voltage of the generator 1 can distinguish two alternating stages: a) the full growth phase flux (Ψ) phase throttle filter 16 and two sections of the phase reactor from their groups 19 and 20 (stage

Figure 00000004
) and b) the stage of partial (or complete) subsidence of the specified flux linkage (stage
Figure 00000005
) With the positive potential of phase bus 2 at the stage:
Figure 00000006
simultaneously increasing currents in the circuits: (capacitor 16) - (inductor 16) - (diode-key rack 17), as well as: (capacitor 18) - (key 17) - (capacitor 22) - (diode 21) - (reactor 19 ), and at the stage:
Figure 00000007
at the same time partially (or completely) the currents in the circuits drop: (inductor 16) - (diode 17) - (capacitor 18) - (valve 18) - (capacitor 16), and also (reactor 19) - (valve 18) - (capacitor 22) - (diode 21). Further, these steps are repeated in a high-frequency-frequency manner qualitatively within the considered half-period of the phase voltage of the starter generator 1, charging the filter capacitor 22 with a continuous current in the phase choke of the input filter 16.

With the negative potential of the phase bus 2, similar processes occur, but with the participation of the phase reactor 20 and the charged filter capacitor 23.

Then both processes are low-periodically qualitatively repeated. In this case, using pulse-width modulation of the control signals and the use of feedback circuits (10, 11) of the control unit 9 in the anchor circuits of the starter generator 1, sinusoidal phase currents are formed, synchronous and in-phase with the corresponding phase voltages, approximating the power factor in these circuits to unit and thereby reducing heat loss in its windings and magnetic circuit, as well as reducing noise emissions. An even greater value of the power factor is achieved with the help of the electromagnetic interconnection between the windings of the chokes 16 and the sections of the reactors 19, 20, which reduces the high-frequency pulsations of the phase currents due to the counter-EMF induction induced in the chokes during key switching.

When the energy is converted back (from link 4 to distribution buses 2, for example, in the starter-generator 1 starting mode), the input filter 16 of the first converter 3 works as an output filter for the second converter 15 (the contactor 24 is closed).

The operation of this converter as the simplest three-phase bridge PWM inverter is widely covered in the literature on power electronics and does not require additional explanations (for example, see the link to the prototype).

Equalization voltage divider 21 performs three functions:

1) as an output three-phase bridge uncontrolled (diode) rectifier during direct conversion as part of the first reversible rectifier-inverter converter 3;

2) as a passive diode switch-inverter with a three-phase trapezoidal output voltage of the distribution bus 13 through the first low-pass filter 14 and

3) as an equalizing voltage divider on the filter rack 22-23, i.e. in the shoulders of the differential link 4 constant increased voltages.

The first of the listed functions is considered above.

The second function does not require special control and is performed automatically when the first is performed due to low-frequency alternating connections through diodes 21 of the extreme terminals of the filter rack 22-23 with stabilized constant potentials relative to the common ground.

The third function (mutual alignment of the absolute values of the potentials mentioned) is performed as follows. Using the control unit 9, pulse-width modulation of the signal in the control circuit of that key 21, which is directly connected to the filter capacitor (from 22 and 23), is performed with

Figure 00000008
voltage and which is connected at the given half-period of the alternating voltage of the starter-generator through the reactor from groups 19, 20 to the switched-on valve 18. Each time this switch is turned on, the current of the specified reactor rises, discharging the indicated (“excessively charged”) capacitor, and after turning off this switch the current of the specified reactor partially (or completely) decreases, charging another ("uncharged") capacitor of the filter rack.

In contrast to the prototype, which uses a variable voltage starter-generator with a stable amplitude (i.e., with electromagnetic excitation from a special inverter exciter), the proposed source can use a much simpler starter-generator in the form of a magnetoelectric machine with permanent magnets on the rotor, having improved mass-energy and reliability characteristics (without a special inverter exciter). Moreover, stabilization of its voltage at an unstable speed of rotation is performed automatically along with stabilization of the rectified voltage on the differential link of constant increased voltage without special additional nodes that degrade the reliability and weight and size characteristics of the device.

Thus, in comparison with the prototype, the proposed autonomous power supply provides the main technical result: improved reliability with increased power factor at the output of the starter generator and its efficiency, as well as with reduced interference emissions by reducing high-frequency ripple currents and voltages in the armature circuit, and while improving the mass-energy characteristics due to the possibility of supplying powerful loads with variable amplitude-stabilized voltage of arbitrary frequency bypassing the inver ora sinusoidal voltage with a limited installed power.

Claims (2)

1. An autonomous power supply containing an electric machine starter-generator of alternating current with unstable parameters, connected by its anchor winding to distribution busbars of alternating voltage with unstable parameters for connecting loads that are not critical to the quality of electricity, and to the AC terminals of the first reversible rectifier-inverter converter with input power factor corrector and with output differential outputs that are connected directly to the differential the constant-voltage link with a grounded medium-voltage busbar for parallel connection of similar sources and the most powerful loads, and are also connected via a sinusoidal voltage inverter to three-phase voltage distribution busbars with stable parameters and through a reversible pulse converter to DC low voltage distribution buses for connecting back-up -battery and associated loads, and in addition - a control unit with circuits about feedback on currents and voltages and with pulse-modulator and relay-signal outputs connected to the control terminals of these converters, characterized in that three-phase AC voltage distribution buses with a stable amplitude are inserted into it to connect powerful AC loads, which are not critical to frequency stability , and the first three-phase inductive-capacitive low-pass filter connected by output terminals to the indicated buses, as well as the second reversible rectifier-invert a converter made in accordance with a three-phase bridge circuit and connected with its DC terminals to the extreme terminals of the differential link of constant increased voltages, and with its AC terminals to the additional terminals of the first reversible rectifier-inverter converter, consisting of an input second three-phase inductive a capacitive filter having additional terminals of two three-phase groups of parallel-split grounding diode-key with oek, two three-phase groups of parallel-split grounding valve-capacitor racks, three two-section phase reactors and an equalizing voltage divider, made according to the three-phase bridge, connected by its AC terminals to the middle terminals of the phase reactors and to the input terminals of the first inductance-capacitive filter, and their findings of direct current - to the extreme terminals of the differential link of constant high voltage, shunted by a two-capacitor filter rack.
2. The autonomous power supply according to claim 1, characterized in that a three-phase electromechanical contactor is connected to it, connected to the output terminals of the chokes of the second inductance-capacitive filter, which, together with the phase reactors of the first reversible rectifier-inverter converter, are made with phase-common magnetic circuits, moreover, pairs of sections of each of the phase reactors are turned on one another, and the three-phase bridges of the second rectifier-inverter converter and surge voltage divider full with counter-parallel diode-key branches in the bridge shoulders.
RU2018103240U 2018-01-29 2018-01-29 Offline power supply RU184526U1 (en)

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Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2011017176A1 (en) * 2009-07-28 2011-02-10 Thx Ltd. Power supply
WO2011022320A1 (en) * 2009-08-20 2011-02-24 American Power Conversion Corporation 3-phase high power ups
RU2426215C2 (en) * 2008-12-03 2011-08-10 Федеральное космическое агентство Федеральное государственное унитарное предприятие НАУЧНО-ПРОИЗВОДСТВЕННОЕ ПРЕДПРИЯТИЕ ВСЕРОССИЙСКИЙ НАУЧНО-ИССЛЕДОВАТЕЛЬСКИЙ ИНСТИТУТ ЭЛЕКТРОМЕХАНИКИ С ЗАВОДОМ имени А.Г. ИОСИФЬЯНА НПП ВНИИЭМ Uninterrupted power supply source for ac loads
RU128040U1 (en) * 2013-01-18 2013-05-10 Николай Петрович Кириллов Electric machine source of medium power

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
RU2426215C2 (en) * 2008-12-03 2011-08-10 Федеральное космическое агентство Федеральное государственное унитарное предприятие НАУЧНО-ПРОИЗВОДСТВЕННОЕ ПРЕДПРИЯТИЕ ВСЕРОССИЙСКИЙ НАУЧНО-ИССЛЕДОВАТЕЛЬСКИЙ ИНСТИТУТ ЭЛЕКТРОМЕХАНИКИ С ЗАВОДОМ имени А.Г. ИОСИФЬЯНА НПП ВНИИЭМ Uninterrupted power supply source for ac loads
WO2011017176A1 (en) * 2009-07-28 2011-02-10 Thx Ltd. Power supply
WO2011022320A1 (en) * 2009-08-20 2011-02-24 American Power Conversion Corporation 3-phase high power ups
RU128040U1 (en) * 2013-01-18 2013-05-10 Николай Петрович Кириллов Electric machine source of medium power

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