RU2343615C1 - Reversible voltage converter for electric power transmission between alternating and constant current systems - Google Patents

Abstract

FIELD: electricity.

SUBSTANCE: invention relates to the field of electric engineering specifically voltage converters intended for direct current consumers energising, and for charging, training charging, forming in automatic optimal charging-discharging mode of accumulators for direct current voltage systems. The invention can be used for uninterrupted power supply of critical consumers at various industrial and military installations (mobile and stationary) with high-stability direct current voltage of two ratings and three-phase alternating current at frequency of 50 Hz and voltage of 380/220 V or one-phase alternating current at frequency of 50 Hz and voltage of 220 V.

EFFECT: providing considerable energy saving in alternating-current mains and achievement of maximal possible fail-free operation of power supply for critical consumers of both direct and alternating current at various purposes installations that use for consumer power supply the single alternating current voltage system and single direct current voltage system.

2 cl, 1 dwg

Description

The invention relates to the field of electrical engineering, in particular, to voltage converters, designed to power consumers of DC voltage, as well as for charging, training charge, molding in automatic optimal charge-discharge mode of storage batteries of DC voltage networks. The invention can be used for uninterrupted power supply with a highly stable DC voltage of two ratings and a three-phase alternating current with a frequency of 50 Hz and a voltage of 380/220 V or single-phase alternating current with a frequency of 50 Hz and a voltage of 220 V for responsible consumers of various objects (mobile and stationary) for industrial and military purposes .

A known uninterruptible power supply device (RF Patent No. 2221320. Uninterruptible power supply multichannel stabilizing device, IPC 8 H02J 7/34, name of the patent holder: Nikitin I.E., Bushuev V.M.), containing a network rectifier connected to an industrial network by AC terminals AC power supply, and DC terminals - to the input terminals of the charge-buffer converter (ЗБП), the DC output terminals of which are connected to the backup battery and the inputs of the voltage converters Submission Form (Mo) dc to dc. By the number of channels of the output voltage, the fault and voltage protection devices are designed according to the high-frequency conversion scheme and consist of an inverter, a control unit with a PWM controller, and a transformer-rectifier unit (TVU), the transformer primary winding of which is connected to the inverter’s AC terminals, and the TVU’s DC outputs output terminals of the device. Moreover, the PNs are made according to the scheme with two input power supply feeders, for which they introduced a control pulse commutator (KIU) and an additional inverter, the input power terminals of which are connected to the output of the mains rectifier and the KIU control input, and the AC outputs to the introduced second primary winding transformer node TVU.

The disadvantage of this uninterruptible power supply device is that it does not provide the ability to recover the energy of the battery in a supply industrial AC network.

In addition, the composition of this uninterruptible power supply device is redundant, since the battery charge is provided by a separate charging and buffer converter, and two inverting channels (with the main and with additional inverters) are used as part of the output DC-DC voltage converters for powering the load, one of which through a network rectifier it works only from a power industrial network, and the second only from a battery.

A known charge-discharge converter (Charging-discharge converter ЗРП-150/50, http://www.blesk-nvf.ru/ZRP 150-50.html), supplied by Elmashprom Limited Liability Company (Supplier: Elmashprom , Russia, Nizhny Novgorod (http://www.promspravka.com/catalog/D/DL/31/l/10/5/50/130/auto/2/Zaryadka 440.html? F = 1 & 1 = 0 ), which is a three-phase thyristor reversible converter designed for charging, training charge, molding in automatic optimum charge-discharge mode up to ten 12-volt and up to five 24-volt rechargeable batteries In the discharge mode, the energy generated by the batteries is inverted to the supply network 3 ~ 50 Hz, 380/220 V. The disadvantage of this charge-discharge converter is that it has only one DC voltage output.

In addition, the converter operating modes (charge, training charge, forming batteries in the automatic charge-discharge mode) are switched manually, which does not allow ensuring uninterrupted power supply (in case of emergency power supply disconnection) from the charge-discharge converter ЗРП-150/50 responsible consumers who are also connected to the power supply 3 ~ 50 Hz, 380/220 V.

The closest in execution analogue, adopted as a prototype of the invention, is a two-stage voltage converter with intelligent protection against overload conditions and short circuit currents (RF Patent No. 2314621 for the invention "Two-stage voltage converter with intellectual protection against overload conditions and short circuit currents", IPC 8 H02J 9/06).

In this two-stage voltage converter, universal power reversible cells are used to rectify AC voltage to DC voltage and to invert DC voltage to AC voltage: single-phase (or, if necessary, three-phase) inverter-rectifier circuits assembled from IGBT keys. The inverter-rectifier bridge circuit has two power inputs / outputs and after applying DC voltage to the corresponding power input / output (when coordinated control of bridge IGBT keys, the so-called PWM control is usually used), it inverts DC voltage to AC voltage and its output to the second power input-output, that is, the power reversing cell in this case works as a controlled inverter. When applying AC voltage to the opposite power input-output of the inverter-rectifier bridge circuit, the AC supply voltage is rectified to DC voltage, and, as a rule, it is not necessary to control IGBT keys of the bridge, that is, the power reversing cell in this case can work as an uncontrolled rectifier.

A two-stage voltage converter consists of: a first channel for voltage conversion of the main DC voltage network with a battery, including a first filter connected in series, a first inverter-rectifier (this converter is used only as a controlled inverter), a first current sensor, a first transformer, and a second inverter - a rectifier (in this converter is used only as an uncontrolled rectifier), a second filter, a second current sensor, a third inverter - a rectifier (in this converter is used only as a controlled inverter), a third filter, a third current sensor and an alternating current network with a group of consumers of alternating current voltage, and from the second channel for converting the voltage of a backup network of direct current voltage to a battery, including a fourth filter connected in series , the fourth inverter-rectifier (in this converter is used only as a controlled inverter), the fourth current sensor, the second transformer, p the fourth inverter-rectifier (in this converter is used only as an uncontrolled rectifier), the fifth filter, the fifth current sensor, the output of which is connected between the second current sensor and the third inverter-rectifier of the first voltage conversion channel of the main DC voltage network, as well as from a multicomponent system control assembled on the basis of two microcontrollers with random access memory, real-time clock, non-volatile memory, two analog-digital x converters, four voltage sensors, three power switch driver blocks, three comparators, three blocking circuits, two discrete input / output modules, an indication and control panel, an information bus adapter, an information exchange bus, an external control system and two galvanically isolated power supplies from the main and reserve network of a direct current voltage.

The disadvantages of the Converter prototype are the following features.

The main disadvantage of this device of a two-stage voltage converter is that it is not reversible, since it does not provide the ability to transfer electricity to the DC power network and, accordingly, the possibility of charging a battery connected to this network.

In addition, in a two-stage voltage converter:

- there is only one output for consumers - an AC voltage output, as a result of which there is no possibility of power supply to DC consumers who require a voltage rating different from the voltage of the DC supply network;

- provides the possibility of uninterrupted power supply only for consumers of alternating current;

- to ensure uninterrupted power supply to AC consumers, it is necessary to connect to two independent DC power supply networks (main and backup power supply);

- in connection with the presence of a second voltage conversion channel operating from a backup DC network, there is a large redundancy of inversion channels.

The objectives of the invention are:

- ensuring effective normal and accelerated charge, training charge, molding in the mode of automatic charge-discharge plates of the battery, which is part of the DC voltage network of the object;

- ensuring the reversibility of the voltage converter with the possibility of recovering the energy stored in the battery into the AC voltage network (both in the molding mode when the battery is discharged and after an emergency shutdown of the AC voltage source);

- ensuring energy savings in the AC network (replenishment of electricity to power consumers of the AC network) in the mode of recovery of energy stored in the battery, instead of its irretrievable loss, for example, by thermal dissipation;

- uninterrupted power supply of responsible consumers with a highly stable DC voltage of two ratings with a wide range of regulation;

- uninterrupted power supply of critical consumers with alternating sinusoidal single-phase or three-phase current voltage ~ 50 Hz, 380/220 V;

- in the complex - the achievement of the maximum possible failure-free power supply for responsible consumers of various objects (mobile and stationary) for industrial and military purposes, both direct and alternating current due to the automatic switching of the modes of transmission of electric energy between AC and DC voltage networks.

The problem is solved in that a reversible voltage converter for transmitting electricity between AC and DC networks, consisting of AC voltage networks connected in series with a group of AC voltage consumers, a first current sensor, a first filter, a first rectifier inverter, a second filter, a second inverter rectifier, a transformer, a third inverter rectifier, a third filter, a DC voltage network with a battery; a second current sensor, a first and second voltage sensor, an analog-to-digital converter, a first, second and third block of power key drivers, a microcontroller with random access memory, a discrete input-output module, an indication and control panel, a real-time clock, non-volatile memory device, information bus adapter, information bus, external control system; to the first input of the analog-to-digital converter the information output of the first current sensor, to the second input through the first voltage sensor is connected the input-output of the AC voltage network with a group of AC voltage consumers, the output of the analog-to-digital converter is connected to the first input of the microcontroller with random access memory, a real-time clock is connected to the second input of the microcontroller with random access memory, and a non-volatile memory device is connected to the third input The display and control panel is connected to the first input-output of the microcontroller with random access memory via the discrete input-output module, an external control system is connected to the second input-output through the information bus adapter and data exchange bus, the first output of the microcontroller with random access memory is the first block of drivers of power switches is connected to the control input of the first inverter rectifier, the first and second group of consumers of DC voltage are introduced, the block protection and uninterruptible power supply with battery, the first group of DC voltage consumers is connected to the output of the second filter, the second group of DC voltage consumers is connected to the output of the DC voltage network with the battery, the protection unit is connected to the gap between the third inverter rectifier and the third filter, the second current sensor is included in the gap between the third filter and the DC voltage network with a battery, to the third analog-to-digital input the information output of the second current sensor is connected to the converter, the input / output of the DC voltage network with the battery is connected to the fourth input through the second voltage sensor, the second output of the microcontroller with random access memory is connected to the control input of the second inverter-rectifier through the second block of power key drivers, the third output through the third block of drivers of the power switches is connected to the control input of the third inverter rectifier, the output of the AC voltage a group of consumers of AC voltage is connected to the input of an uninterruptible power supply with a battery, the output of an uninterruptible power supply with a battery is connected to the corresponding power inputs of the microcontroller with random access memory of an analog-to-digital converter, the first, second, and third block of power key drivers, discrete input module - output, display and control panels and information bus adapter.

In addition, in a reversible voltage converter for transmitting electricity between AC and DC networks, the microcontroller is made with the possibility of manual control using the display and control panel, automatically polling the first and second voltage and current sensors, automatically controlling the operation of the second inverter-rectifier in the mode of electric power transmission from AC voltage network to DC voltage network, automatic normal or accelerated battery charge Areas of the DC voltage network, automatic coordinated control of the third and first inverter-rectifier in the mode of energy transfer from the DC voltage network with the battery to the AC voltage network (in the energy recovery mode, when the battery of the DC voltage network is discharged), automatic transition to the energy recovery mode after an emergency shutdown of the AC voltage source, automatic return when voltage is restored changes in the AC network to the mode of transmission of electricity from the AC voltage network to the DC voltage network.

The essence of the invention lies in the fact that the proposed voltage converter implements automatic reversal of work to enable the transmission of electricity from the AC network to the DC network and vice versa (from the DC network to the AC network), which allows not only to constantly maintain the battery in working condition condition, while ensuring the return of energy (in the discharge mode of the battery) accumulated in the battery into the AC mains and, accordingly, providing significant energy savings in the AC network, it is also possible to achieve the maximum possible fail-safe power supply for responsible consumers of both direct and alternating current at various facilities using one AC voltage network and one DC voltage network for power supply of consumers.

The drawing shows a structural diagram of a reversible voltage Converter for transmitting electrical energy between AC and DC networks.

According to the drawing, the reversible voltage Converter includes the first 1 and second 2 groups of consumers of DC voltage, connected in series to the AC voltage network with a group of consumers of AC voltage 3, the first current sensor 4, the first filter 5, the first inverter rectifier 6, the second filter 7, a second inverter-rectifier 8, a transformer 9, a third inverter-rectifier 10, a protection unit 11, a third filter 12, a second current sensor 13, a DC voltage network with a battery 14; first 15 and second 17 voltage sensors, analog-to-digital converter 16, first 18, second 19 and third 20 power key driver blocks, uninterruptible power supply with battery 21, microcontroller with random access memory 22, discrete input-output module 23, clock real-time 24, non-volatile storage device 25, data bus adapter 26, data exchange bus 27, external control system 28, display and control panel 29. To the first input of the analog-to-digital Converter 16 the information output of the first current sensor 4 is switched on, the input-output of the AC voltage network with a group of AC voltage consumers 3 is connected to the second input through the first voltage sensor 15, the output of the analog-to-digital converter 16 is connected to the first input of the microcontroller with random access memory 22, a real-time clock 24 is connected to the second input of the microcontroller with random access memory 22, a non-volatile memory device 25 is connected to the third input, to the first input - the output of the microcontroller with random access memory 22 through the discrete input-output module 23 is connected to the display and control panel 29, an external control system 28 is connected to the second input-output via the information bus adapter 26 and the data exchange bus 27, the first output of the microcontroller with random access memory 22 through the first block of drivers of the power switches 18 is connected to the control input of the first inverter-rectifier 6, the first group of consumers of DC voltage 1 is connected to the output at the second filter 7, the second group of consumers of DC voltage 2 is connected to the output of the DC voltage network with a battery 14, the information output of the second current sensor 13 is connected to the third input of the analog-to-digital converter 16, and the input is connected to the fourth input through the second voltage sensor 17 - the output of the DC voltage network with the battery 14, the second output of the microcontroller with random access memory 22 through the second block of drivers of the power keys 19 is connected to the control to the input of the second inverter-rectifier 8, the third output through the third driver block of the power switches 20 is connected to the control input of the third inverter-rectifier 10, the output of the AC voltage network with a group of AC voltage consumers 3 is connected to the input of an uninterruptible power supply with a battery 21, the output of an uninterruptible power supply with a battery 21 is connected to the corresponding power inputs of the microcontroller with random access memory 22 analog-to-digital 16, the forming, the first 18, second 19 and third 20 power unit key driver module discrete IO 23, the display and control panel 29 and data bus 26 of the adapter.

The proposed Converter operates as follows.

When applying a supply voltage from the AC voltage network 3, power is supplied to the group of AC voltage consumers connected to this network, as well as an uninterruptible power supply with a battery 21.

The supply voltage of the AC voltage mains 3, passing through the first current sensor 4 and the first filter 5, is fed to the first inverter-rectifier 6, which in this case works as an uncontrolled AC voltage rectifier to DC and then goes to the second filter 7. The rectified and the smoothed DC voltage from the output of the second filter 7 goes to the first group of consumers of DC voltage 1 and to the input of the second inverter-rectifier 8.

An uninterruptible power supply with a battery 21 generates the necessary voltage for powering the microcontroller with random access memory 22, analog-to-digital converter 16, first 18, second 19 and third 20 of the power key driver block, discrete input-output module 23, display and control panel 29 and the adapter of the information bus 26. After receiving power supply to the random access memory of the microcontroller 22 from the non-volatile memory 25 is loaded control program, which provides the possibility of manual selection and setting operation mode of the voltage converter via the display and control panel 29 via a digital input-output unit 23.

First of all, it is possible to set the normal or accelerated charge of the battery of the DC voltage network 14. In this case, the microcontroller 22, using the first 15 and second 17 voltage sensors and analog-to-digital converter 16, determines the voltage values in the AC voltage network 3 and in the network DC voltage 14 and uses this information to generate control actions through the second driver block of power switches 19 to the second inverter-rectifier 8, which in this case It works as a controlled DC voltage to AC inverter. The AC voltage generated by the second inverter-rectifier 8 is supplied to a transformer 9, with which the galvanic isolation of the AC voltage network 3 from the DC voltage network 14 and the necessary transformation (lowering or increasing the value of the AC voltage) are carried out. Next, the obtained AC voltage is supplied to the third inverter-rectifier 10, which in this case acts as an uncontrolled AC voltage rectifier to DC, and then through the protection unit 11, the third filter 12 and the second current sensor 13 to the DC voltage network with a battery battery 14. In this case, depending on the previously selected manual mode, a normal or accelerated battery charge of the DC voltage network is carried out 14. In addition, the DC voltage network with the battery 14 receives power from the second group of consumers of DC voltage 2.

After the battery is charged, the voltage converter can be manually transferred to the discharge mode using the display and control panel 29, in which the energy of the DC voltage network 14 stored in the battery is returned through the second current sensor 13, the third filter 12 and the protection unit 11 to the third inverter-rectifier 10. The protection unit 11 is designed to protect the power circuits of the voltage converter from switching switching overvoltages and to maintain the continuity of the discharge current of the battery yatornoy battery in the power transmission mode from the network voltage DC voltage 14 to an AC network 3.

The third inverter-rectifier 10 under the control of the microcontroller 22, using the third block of drivers of the power switches 20, converts the DC voltage into AC, that is, in this case, the third inverter-rectifier 10 acts as a controlled inverter of the DC voltage into AC. Next, the AC voltage is transformed in the transformer 9, rectified by the second inverter-rectifier 8, which in this case works as an uncontrolled AC voltage rectifier into DC, and after the second filter 7 is supplied to the first group of consumers of DC voltage 1. In addition, DC voltage arrives at the first inverter-rectifier 6, which under the control of the microcontroller 22 using the first block of drivers of the power switches 18 produces voltage conversion post yannogo-AC, i.e. in this case the first inverter-rectifier 6 operates as a voltage controlled DC to AC inverter. In this case, the microcontroller 22 using the first voltage sensor 15 and the analog-to-digital converter 16, the real-time clock 24 synchronizes the frequency, phase and amplitude of the voltage generated by the first inverter-rectifier 6 and the AC voltage 3 and adjusts the value of the power transmitted from the DC voltage network 14 to the AC voltage network 3.

When the training charge-discharge of the battery is realized (when forming the plates of the battery), the modes of energy transfer from the AC voltage network 3 to the DC voltage network 14 and back are automatically switched by the microcontroller 22.

Thus, in a reversible voltage converter, energy is saved in the alternating current network (replenishing electric energy for powering the consumers of the alternating current network) in the mode of recovering the energy stored in the battery instead of its irretrievable loss, for example, from thermal dissipation.

In addition, with the disappearance of the supply voltage in the AC voltage network 3 in the mode of transferring energy from the AC voltage network 3 to the DC voltage network 14, the microcontroller 22 still has the opportunity (using an uninterruptible power supply with a battery 21) to maintain intelligent control voltage converter. In this case, the microcontroller 22 automatically switches the first inverter-rectifier 6, the second inverter-rectifier 8, and the third inverter-rectifier 10 to a mode that provides energy recovery and transmission from the DC voltage network 14 to the AC voltage network 3, while maintaining uninterrupted power supply both direct current consumers (the first 1 and second 2 groups of direct current voltage consumers) and alternating current consumers (a group of alternating current voltage consumers in the mains AC voltage 3).

When restoring the voltage in the AC network, the microcontroller 22 is able to return the reverse voltage converter to the mode of transmission of electricity from the AC voltage network 3 to the DC voltage network 14.

To enable remote monitoring and control of the proposed voltage converter, an interface bus adapter 26 is provided, providing remote connection to an external control system 28.

Industrial applicability of the invention is determined by the fact that the proposed reversible voltage converter can be made in accordance with the above description and drawing on the basis of well-known components (for example, the information bus can be made on the basis of interfaces RS-232, RS-485, CAN, MIL-STD 1553 V, Ethernet) and technological equipment and is used for uninterrupted power supply of various consumers with AC and DC voltage at various facilities.

The proposed technical solutions are practically implemented in a prototype small-sized charge-discharge converter for pilot prototypes created by the IRIS Closed Joint-Stock Company for reversing converters designed to transfer electrical energy between ship AC and DC networks and uninterrupted power supply of 27 V DC consumers and 220 V and three-phase alternating current with a frequency of 50 Hz and a voltage of 380/220 V in the rescue deep-sea ap Arata (SGA) Project 18270 "Bester" and rescue decompression module MSD-400.

Thus, the proposed reverse voltage converter has a very wide functionality, providing the transfer of electrical energy from the AC network to the DC network and vice versa, allowing during operation to automatically maintain the battery in good condition, providing significant energy savings in the AC network, and in complex - allows you to achieve the highest possible failure-free power supply of responsible consumers as a constant Both AC and AC current at objects (for example, ship) with one AC network and one DC network.

Based on the foregoing and the results of our patent information search, we believe that the proposed reverse voltage converter for transmitting electricity between AC and DC networks meets the criteria of "novelty", "inventive step" and can be protected by a patent of the Russian Federation for invention.

Claims (2)

1. A reversible voltage converter for transmitting electricity between AC and DC networks, consisting of AC voltage networks connected in series with a group of AC voltage consumers, a first current sensor, a first filter, a first rectifier inverter, a second filter, a second rectifier inverter, a transformer, a third inverter rectifier, a third filter, a DC voltage network with a battery; a second current sensor, a first and second voltage sensor, an analog-to-digital converter, a first, second and third block of power key drivers, a microcontroller with random access memory, a discrete input-output module, an indication and control panel, a real-time clock, non-volatile memory device, information bus adapter, information bus, external control system; to the first input of the analog-to-digital converter the information output of the first current sensor, to the second input through the first voltage sensor is connected the input-output of the AC voltage network with a group of AC voltage consumers, the output of the analog-to-digital converter is connected to the first input of the microcontroller with random access memory, a real-time clock is connected to the second input of the microcontroller with random access memory, and a non-volatile memory device is connected to the third input The display and control panel is connected to the first input-output of the microcontroller with random access memory via the discrete input-output module, an external control system is connected to the second input-output through the information bus adapter and data exchange bus, the first output of the microcontroller with random access memory is the first block of drivers of the power switches is connected to the control input of the first inverter-rectifier, characterized in that the first and second group of voltage consumers are introduced into it DC power supply, protection unit and uninterruptible power supply with battery, the first group of DC voltage consumers is connected to the output of the second filter, the second group of DC voltage consumers is connected to the output of the DC voltage network with the battery, the protection unit is connected to the gap between the third the rectifier inverter and the third filter, the second current sensor is included in the gap between the third filter and the DC voltage network with the battery, to the the input of the analog-to-digital converter is connected to the information output of the second current sensor, the input / output of the DC voltage network with the battery is connected to the fourth input through the second voltage sensor, the second output of the microcontroller with random access memory is connected to the control input of the second through the second block of power key drivers inverter-rectifier, the third output through the third block of drivers of power switches is connected to the control input of the third inverter-rectifier, the output of the network AC voltage with a group of AC voltage consumers is connected to the input of an uninterruptible power supply with a battery, the output of an uninterruptible power supply with a battery is connected to the corresponding power inputs of a microcontroller with random access memory of an analog-to-digital converter, the first, second and third block of power key drivers , discrete input-output module, display and control panel and information bus adapter. 2. The reversible voltage Converter for transmitting electricity between AC and DC networks according to claim 1, characterized in that the microcontroller is made with the possibility of manual control using the display and control panel, automatic polling of the first and second voltage and current sensors, automatic control of the second inverter-rectifier in the mode of electric power transmission from the AC voltage network to the DC voltage network, automatic normal or accelerated charge ak a dummy battery of the DC voltage network, automatic coordinated control of the third and first inverter-rectifier in the mode of transferring energy from the DC voltage network with the battery to the AC voltage network (in the energy recovery mode, when the battery of the DC voltage network is discharged), automatic transition to the mode of energy recovery after an emergency shutdown of the AC voltage source, automatic return, when anovlenii line voltage AC mode to the power transmission from the AC voltage into a DC voltage network.