WO2019013732A1

WO2019013732A1 - Dynamic voltage compensatofr

Info

Publication number: WO2019013732A1
Application number: PCT/UA2018/000027
Authority: WO
Inventors: Дмитрий Валерьевич ХАЧАТУРОВ
Original assignee: Дмитрий Валерьевич ХАЧАТУРОВ
Priority date: 2017-07-12
Filing date: 2018-03-26
Publication date: 2019-01-17

Abstract

The claimed invention relates to electrical engineering and can be implemented in the form of a device that can mounted at the input of equipment requiring neutralization of the effect of voltage slumps and surges of a supply network by means of precise and smooth regulation of AC voltage. The essence of the invention consists in that a booster transformer of a dynamic voltage compensator is designed to be capable of operating in at least two operating modes. In one of said operating modes, at least one high-voltage winding is connected to a controllable inverter and the other winding or group of windings is series-connected to a network between the current source and a consumer. In addition, in the second of the possible operating modes, low-voltage windings of the booster transformer can be reswitched by means of at least one controllable switching device to an electrical circuit so as to be capable of providing operation of the booster transformer without connecting to a supply network, wherein the inverter is connected to an energy accumulation and transmission unit so as to be capable of supplying the booster transformer.

Description

Invention Name: Dynamic Voltage Compensator Technical Field:

The invention relates to electrical engineering and can be implemented in the form of a device installed at the input of equipment that needs to neutralize the effect of subsidence and power supply voltage surges, by means of precise and smooth adjustment of alternating voltage.

Prior art:

In connection with the increasing requirements for the quality of electric power in modern automated control systems for industrial and technological processes and their widespread use, it became necessary to use dynamic voltage distortion compensators (DKIN). Known DKINs are devices containing a rectifier and an inverter with phase control based on fully controlled voltage sources, which are connected to the consumer’s supply network and through a voltage boost transformer (VDT) creates voltage addition ΔΖ7 on the secondary winding, compensating for voltage dips.

From patent for invention RU2393611 dated 06/27/2010, IPC H02J 9/06, the patentee of which is Lipetsk State Technical University (LSTU), a device is known for dynamic restoration of voltage dips, which in order to protect the receiver from voltage dips during short interruptions of power supply

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SUBSTITUTE SHEET (RULE 26) The device supplies a compensated voltage generated by a converter fed from a charger in a DC circuit, which includes an absorbing compensator that forms an energy damper to regulate power flow, which serves to stabilize the compensation voltage, to connect to the terminals of the electric receiver through the VDT during the elimination short-term power failure.

The disadvantages of this technical solution include the inability to switch to the backup load power line, reduced response speed to network degradation, as well as accuracy of dips and voltage surges compensation within 10% of the nominal voltage, which may affect the operation of equipment sensitive to such quality indicators of supply voltage.

Also from the patent JY ° US5905367A from 18.05.1999; IPC H02J3 / 12, the patentee of which is Siemens Westinghouse (USA), knows the device containing the control system, booster transformer, one of the windings or groups of windings, which is connected to the power supply network, and the other winding or group of windings, is connected to the voltage source of the voltage booster.

One of the embodiments of the invention provides for the presence of two transformers, one of which is connected to at least one inverter, is designed with the possibility of a voltage booster and is connected to the network between the voltage source and the load. At the same time, the aforementioned single-phase inverter is also connected to a common source of energy storage and transmission, and is connected to the second booster transformer,

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SUBSTITUTE SHEET (RULE 26) designed to power the load from the specified sources of accumulation and transmission of energy.

The disadvantages of this technical solution include the presence of essentially two booster transformers, one of which is connected to the network between the power source and the load, and the second between the source of energy storage and the load, which can lead to an increase in electricity consumption, as well as an increase in the cost of the device.

We accept the specified technical solution for the closest analogue. Technical task:

The technical problem to be solved, the claimed invention is the creation of a voltage compensator, providing the supply voltage of the consumer’s electrical network within the limits of ± 1% of the nominal UHOM voltage, in conditions of significant (up to 30% and more) deviations of the supply voltage from the nominal UHOM, as well as ensuring that the equipment can operate in the absence of power until the transition to the backup power line.

Technical result:

The technical result achieved from the implementation of the claimed invention is to simplify the design of the device, improve the quality of consumer power by eliminating significant subsidence and power supply surges lasting more than 2 ms, as well as reducing financial and technological losses that may occur due to low reliability power supply, by maintaining the voltage on the load for at least 1 second with no input voltage, which allows guaranteed o Transfer consumers to a backup power line. s

SUBSTITUTE SHEET (RULE 26) The essence of the claimed invention lies in the fact that the booster transformer of the dynamic voltage compensator is designed to work in at least two operating modes "Voltage Compensation" and "Uninterrupted Power Supply UPS". In one of which, at least one high voltage winding is connected to a controlled inverter, and the other winding or group of windings is connected in series to the network between the current source and the consumer, low voltage, with the possibility of providing booster booster. In the second of the possible modes of operation, the low-voltage windings of the booster transformer, switched by means of at least one controlled switching device, to an electric circuit with the possibility of ensuring the operation of the transformer without connecting to the mains, while the inverter is connected to the accumulation and transmission link energy with the ability to power booster transformer.

Dynamic voltage compensator, also configured to transition between operating modes and operating modes of booster transformer, through a control system that includes at least one control unit, functionally connected with it, controlled devices, configured to monitor network operating parameters and generate control signals depending on the operating mode.

Dynamic voltage compensator is designed to operate in at least two operating modes, in one of which the working circuit includes at least one controlled inverter functionally connected to the booster transformer, and adapted to

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SUBSTITUTE SHEET (RULE 26) bypassing and switching to a mode that excludes from the working circuit, the specified controlled inverter and booster transformer.

Dynamic voltage compensator is made with the possibility of bypassing through controlled high-speed switching elements and automatic mechanical switch connected in parallel.

Brief Description of the Drawings:

The essence of the invention is illustrated, but not limited to the following images:

figure 1 - structural diagram of the voltage compensator;

Fig.2 is a functional block diagram of the control system of the voltage compensator.

FIG. 3 is a block diagram in the “Voltage Compensator” mode; 4 is a structural diagram in the mode "Uninterrupted Power UPS"; 5 is a structural diagram in the "Bypass".

Description of carrying out the invention:

The claimed technical solution provides for various options and alternative forms of implementation. A specific embodiment is shown by diagrams in the drawings and in the description of the invention. The described technical solution is not limited to the specific disclosed form and may cover all possible variants of execution, equivalents and alternatives, within the framework of the essential features disclosed in the claims.

Dynamic voltage compensator, is a software and hardware complex that provides neutralization of the effect of subsidence and power supply voltage surges on electrical equipment of consumers.

Dynamic voltage compensator (figure 1), contains booster transformer 1, one of the windings or groups

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SUBSTITUTE SHEET (RULE 26) windings, which is connected to the power supply between the current source 2 and the load 3, and the other winding or group of windings is connected to a controlled voltage source of the booster, represented in the form of at least one controlled inverter 4, configured to change the voltage on one or group of windings of booster transformer, as well as the recovery of electrical energy into the power supply network.

The voltage compensator is designed to work in at least two operating modes. In one of the operating modes, such as the “Voltage Compensation” (KN) mode, the working circuit includes at least one controlled inverter 4, functionally connected to the booster transformer 1. In this case, the said inverter is functionally connected to the controlled device 5 accumulation and transmission of energy, as well as a DC link, including at least one controlled active rectifier 6 and controlled charging device 7. The specified working circuit is configured to bypass, by means of , a high-speed switching device 8, and a mechanical circuit breaker 9, connected in parallel, and switching to a mode that excludes the specified inverter and booster transformer, bypass mode from the working circuit. Along with this, the controlled switching devices 10, 11 serve to switch between the operation modes of the booster transformer.

As an embodiment of the invention, when using a single-line circuit, booster transformer can be made three-winding. The booster transformer is configured to operate at least

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SUBSTITUTE SHEET (RULE 26) - in two operating modes, such ka "Voltage Compensator" (KN) and "Uninterrupted Power Supply" (UPS). These modes of operation VDT, can be implemented when the dynamic voltage compensator in the mode "Voltage Compensation"

In the KN mode, at least one high-voltage winding of 12 volts of the auxiliary transformer is connected to the controlled inverter and connected to the zero point 13 by means of a controlled switching device 10, and another winding or group of windings 14 is low-voltage and connected in series to the network the current source and the consumer, low voltage through a controlled switching device 11, with the ability to provide boosters.

In the second possible mode of operation, the UPS mode, a low-voltage winding or a group of windings of a booster transformer, switched by means of at least one controlled switching device 11 are connected to an electrical circuit, such as a star, with the possibility of ensuring the operation of the VDT without connection to the mains, with Thereby, the high-voltage winding is closed to the zero point 13 by means of a controlled switching device 10, and the inverter is connected to the power storage and transmission link with the power supply I booster transformer, until the transition to the backup power line.

In the second of the possible modes of operation of the dynamic voltage compensator, the “Bypass” mode, the minimum power consumption with continuous control of the input voltage can be ensured by comparing with a predetermined value, as well as the complete disconnection of elements of the control system and controlled devices from the network, while maintaining consumer nutrition. In the Bypass mode in case the mains voltage

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SUBSTITUTE SHEET (RULE 26) is within the range of user-defined values, the load is supplied bypassing the booster transformer. The criterion for the transition from the “Bypass” mode to the “KN” mode is the voltage output outside the specified value, or the user sets the “KN” mode.

At the same time, the voltage compensator is configured to transition between operating modes and modes of operation of the booster transformer, by means of a control system (FIG. 2), which includes at least one control unit 15, functionally connected with it, controlled devices, configured with the ability to control network operating parameters and generation of control signals depending on the operating mode. The said control unit 15 performs a general control over the operating modes of the voltage compensator, controls the input voltages, output voltages and currents, generates task signals and organizes the exchange of information with controlled devices through a system of controllers.

The system of controllers includes: the controller 16 of the controlled inverter, the controller 17 of the controlled active rectifier, the controller 18 of the controlled charger, the controllers 19, 20 of the controlled energy storage and transmission device, the controller 21 of the controlled switching devices.

To coordinate the work of controllers of individual controlled devices that perform the same functions, intermediate controllers (not shown) associated with the control unit may be used.

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SUBSTITUTE SHEET (RULE 26) Industrial Applicability:

Describing the claimed technical solution, it is necessary to indicate the features of the operation of its controlled devices and the connections between them in the main operating modes.

The main operating modes of the proposed technical solution are: the mode "Voltage Compensation" and "Bypass".

In the "Voltage Compensation" mode (Fig. 3), the working circuit includes a volto additional transformer 1, a controlled inverter 4, a DC link connected with it with an energy storage and transfer device 5, the switching device 11, is open for passing the supply voltage (bold dashed line ) to load. At the same time, by means of the control unit 15, the input voltage is continuously monitored and compared with a predetermined value, as well as the generation and transmission of control signals to the controlled devices by means of appropriate controllers.

In the case of voltage deviation from the setpoint, controlled by the controller 16, the inverter dynamically generates voltages that are transmitted to the winding or a group of low-voltage windings of the booster transformer 1 (thin dashed lines) connected to the network between the power supply 2 and the load 3. Thus, in the supply mains is added, the missing voltage is either removed, and then returned as a recovery. When this is controlled, by the controller 17, an active rectifier 6 connected to the controlled controller 18, the charger 7, maintains the DC link voltage at a predetermined level, by supplying power from the network or returning excess energy accumulated by the DC link to the network, which ensures normal operation of the managed

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SUBSTITUTE SHEET (RULE 26) inverter, in particular, and products in general. In this mode, the specified voltage on the load side is formed with an error less than 1% of the nominal value of the UHOM network voltage.

In the case of significant failures of the supply voltage of more than 30% of the nominal, or its complete absence, booster transformer goes into UPS mode (figure 4), by re-switching the windings of booster transformer, namely, the circuit of the high voltage winding 12 to the zero point 13 controlled switch device 10 , and disconnecting the external supply voltage, by turning off the switching device 11. At the same time, the power storage and transmission device 5 controlled by the controllers 19, 20 is switched on This can be done, for example, in the form of a block of capacitors, which provides power to load 3 at the level of nominal voltage for a time sufficient to transfer consumers to a backup power line. After switching to the backup power line, the re-switching of the mentioned switching devices 10, 11 and the corresponding windings of the booster transformer for operation in the CL mode is carried out.

Also one of the features of the proposed technical solution is the implementation of planned and emergency transitions to the "Bypass" mode (figure 5).

The transition is made by simultaneously sending signals to the control unit 15, controlled by the controller 21, the high-speed switching device 8 and applying the command to turn on the automatic mechanical switch 9. The controlled switching device 8 is turned on first, after which the automatic mechanical switch 9 is activated.

SUBSTITUTE SHEET (RULE 26) timing, switching device control 8 is turned off, and only the automatic mechanical switch remains in operation. As a result of switching on the “Bypass” mode, the working circuit is excluded from the consumer's power supply circuit, and the current flows to the load (thick dashed line), bypassing the booster transformer, and the inverter forms a voltage (thin dashed line) on the VDT, which ensures its unstressed switching on to the network when turning off the Bypass mode with switching to the KN mode.

The implementation of the proposed technical solution contributes to the achievement of this technical result, providing an improvement in the quality of the power supply at the load by eliminating significant drawdowns and power supply surges lasting more than 2 ms, and also realizing the possibility of switching to a backup power line, ensuring uninterrupted operation of electrical equipment using at the same time, one booster transformer, made with the ability to work, both from the network and from the source of accumulation and transmission energy, by re-switching the corresponding windings of VDT.

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SUBSTITUTE SHEET (RULE 26)

Claims

Claims of the invention Dynamic voltage compensator

1. Dynamic voltage compensator, including control system, booster transformer, one of the windings or groups of windings, which is connected to the power supply network, and the other winding or group of windings, is connected to the voltage addition source of the booster, which is designed to work, according to at least in two operating modes, in one of which at least one high voltage winding is connected to a controlled inverter, and another winding or group of windings performed It is low-voltage and is connected in series to the network between the current source and the consumer, low voltage, with the possibility of providing voltage boosters, while in the second of the possible modes of operation, a low-voltage winding or group of windings of the booster transformer is re-connected by means of at least one controlled switching device into the electric circuit, with the possibility of transformer operation without connection to the mains, while the inverter is connected to the accumulation link and energy reduction with the ability to power booster transformer.

2. Dynamic voltage compensator according to claim 1 differs in that it is designed to work in at least two operating modes, in one of which the working circuit includes at least one controlled inverter functionally connected to the booster transformer, and is made with the possibility of bypassing and switching to a mode that excludes from the working circuit, the specified controlled inverter and booster transformer.

3. Dynamic voltage compensator according to claim 1 differs in that it is made with the possibility of bypassing through controlled

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SUBSTITUTE SHEET (RULE 26) switching device and automatic mechanical switch connected in parallel.

4. Dynamic voltage compensator according to claim 1, characterized in that it is adapted to transition between operating modes and operating modes of the transformer, by means of a control system that includes at least one control unit functionally connected to it, controlled devices, configured with the ability to control the network operating parameters and the formation of control signals depending on the operating mode.

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SUBSTITUTE SHEET (RULE 26)