KR101370490B1 - The apparatus and method for compensation of voltage-dip - Google Patents

Abstract

The present invention relates to a dynamic voltage restorer which blocks a main system and supplies a synchronous voltage which is identical with a normal system voltage before a voltage drop period to a load and stably operates a manufacturing line. Therefore, the dynamic voltage restorer solves a problem which can be generated in the manufacturing line due to momentary voltage drop of common power. The present invention performs reliable determination regarding the momentary voltage drop of a practical external voltage by measuring a voltage of system input power and detecting a frequency and a phase in real time and performs execute momentary voltage drop compensation. The present invention includes a protection circuit which can protect a device by determining an error of a control unit and provides a stable dynamic voltage restorer and a compensating method. The present invention applies a super capacitor (EDLC) when electric energy is stored in the momentary voltage drop and considers that the device is damaged by large over-current if the electric energy for compensation is charged in the ELCD and includes a preparatory charging unit which performs the preparatory charging in the initial operation or re-operation after operation stop and provides the stable dynamic voltage restorer and the compensating method. [Reference numerals] (10) System power switch unit; (100) Compensation current detection unit; (110) Output current detection unit; (120) Compensation voltage detection unit; (130) Control unit; (140) Warning unit; (20) Momentary power failure prevention switch unit; (30) Bypass switch unit; (40) Compensation voltage supply unit; (50) Momentary voltage drop detection unit; (60) Control power supply unit; (70) Control power error detection unit; (80) PWM output unit; (90) Charge voltage detection unit; (AA) System input power; (BB) Output; (CC) Control power

Description

Voltage Drop Compensation Device and Compensation Method {THE APPARATUS AND METHOD FOR COMPENSATION OF VOLTAGE-DIP}

According to the present invention, when a dip voltage occurs in the manufacturing process of a production equipment system in a large-scale plant and semiconductor industry, the main system is disconnected and the load is supplied with a phase-locked voltage equal to the previous normal system voltage during the voltage dip. The present invention relates to an instantaneous voltage drop compensation device for stably operating a manufacturing line to solve a problem that may occur in a manufacturing line by an instantaneous voltage drop of a power supply.

In recent years, the manufacturing process is complicated and prolonged due to the advancement of the production system in the large-scale plant and semiconductor industries.

If the manufacturing line is stopped due to the instantaneous voltage drop of the power source used in such a large-scale plant and semiconductor industrial factory, there is a problem that an increase in manufacturing cost and a delay in delivery of the product occurs due to the generation of defective products.

Such occurrence of instantaneous voltage drop is mainly detected by a protection relay when a short circuit fault or ground fault occurs due to a lightning strike on the transmission line, and is mainly focused on the fault point while removing the faulty power system. The phenomenon of voltage drop occurs.

The present invention is to compensate for the voltage drop during such a voltage drop.

Republic of Korea Patent Publication No. 10-1233544, "Dynamic instantaneous voltage drop compensation device" comprises an inverter switching means and a bypass means of the power to store the rectified power, and to supply the stored power when the instantaneous voltage drop occurs do.

The instantaneous voltage drop compensator relates to a dynamic voltage dip compensator that can be used regardless of an input voltage.

However, the instantaneous voltage drop compensator has a technical feature that the compensation control device can be configured irrespective of the input voltage, and a means for protecting the equipment against an abnormality of the instantaneous voltage drop compensator is provided. Can cause malfunctions, and the administrator has no way of recognizing it, causing significant damage to expensive equipment.

In addition, the input power is stored to compensate for the instantaneous voltage drop, and when the large current is momentarily input and stored when restarting after excessive current flows for the first time or stops for a long time, the storage means (charge storage) Large losses can occur.

In the present invention, by measuring the voltage of the external power supply to detect the frequency, phase in real time to make a reliable determination of the actual instantaneous voltage drop of the external voltage, accurate instantaneous voltage drop compensation can be made, of course, It is to provide a stable instantaneous voltage drop compensation device and a compensation method by configuring a protection circuit to determine the abnormality of the voltage drop control means to protect the device.

In addition, in the present invention, when storing the electrical energy to be provided during the instantaneous voltage drop, when applying a supercapacitor (EDLC), and charging the electrical energy for compensation in the supercapacitor, a large amount of overcurrent flows instantaneously that the device may be damaged Thus, by reconfiguring the pre-charge means to make a pre-charge when restarting after the initial operation and long-term operation stops, to provide a stable instantaneous voltage drop compensation device and compensation method.

The instantaneous voltage drop compensating apparatus includes, as a main technical configuration, a compensation voltage supply means, a bypass means for a protection operation of the compensation voltage supply means, and a precharge means in charge control of electrical energy stored for generation of a compensation voltage. do.

The system power switch unit for disconnecting the grid input power from the load during the instantaneous voltage drop, the momentary power failure prevention switch unit for preventing the instantaneous power failure when the system power is supplied directly to the load side during bypass, and from the malfunction of the voltage drop. To protect the circuit, the bypass switch unit for supplying the grid power to the load, and the compensation voltage for charging and storing the grid input voltage and supplying the load with the same phase-locked voltage as before the voltage drop to the load during the voltage drop. Supply unit, instantaneous voltage drop detection unit that detects the grid input voltage, measures the grid input voltage from the detected voltage, detects dip voltage and redundancy, and control power supply for supplying control power from the grid input power supply. A supply unit, a PWM output unit for charging the compensation voltage supply unit and an inverter voltage output under the control of the control unit, and A charge voltage detector for detecting a charge low voltage by detecting a charge voltage of the compensation voltage supply unit, a compensation current detector for detecting a compensation overcurrent by measuring a compensation current from a compensation output provided from the compensation voltage supply unit, and The output current detector detects the output current supplied and detects the output overcurrent and the harmonic components by the load, and when the instantaneous voltage drop is detected through the instantaneous voltage drop detection unit, switches off the grid input power by switching the grid power switch. By supplying and controlling the phase-synchronized voltage equal to the normal grid voltage to the load through the compensation voltage supply unit, and controlling the bypass after stopping the compensation operation to prevent damage to the device due to malfunction of the compensation operation by monitoring the compensation current and load current. To control the notification to notify the administrator through the alert alarm means Including fishermen, alarm notification means for notifying the alarm situation to the manager of the instantaneous voltage drop protection device according to the control of the control unit is characterized in that formed.

And the compensation method of the instantaneous voltage drop compensation device of the present invention,

An input voltage storing process of detecting an input voltage, frequency, and phase of a grid input power supply, and storing the detected input voltage, frequency, and phase;

An instantaneous voltage drop detection process for detecting an instantaneous voltage drop in comparison with a system input voltage and a current input voltage during a set previous period, and detecting recovery after an instantaneous voltage drop;

When the instantaneous voltage drop is detected through the instantaneous voltage drop detection process, a compensation voltage supply process for generating a compensation voltage by inverting electrical energy stored in the compensation voltage supply unit and supplying it to the load;

A system input power interruption process of shutting off a system input power connected to a load when an instantaneous voltage drop is detected through the instantaneous voltage drop detection process;

A compensation operation determination process of detecting a compensation current and a load current supplied to the load and determining whether the compensation voltage is normally supplied from the detected compensation current and the load current;

If it is determined through the compensation operation determination process that the compensation voltage supply operation is not performed normally, the bypass process for bypassing the system input power by operating the bypass switch unit;

A recovery process for synchronizing the compensation power with the grid input power and turning on the grid power switch unit when the recovery is detected through the instantaneous voltage drop detection process and connecting the grid input power to the load to recover the power;

When the recovery process is completed, the charging voltage supply unit charging process of charging the voltage to the compensation voltage supply unit by checking the charging voltage of the compensation voltage supply unit,

And the like.

According to the present invention, when a voltage dip (DIP) occurs in the manufacturing process of the production equipment system in a large-scale plant and semiconductor industry, in performing a compensation operation to shut off the main system and provide a compensation power supply, By configuring the protection means for notifying the compensation operation error situation and protecting the device, it is possible to implement a stable instantaneous voltage drop compensation device.

In addition, by configuring the pre-charging means when charging and storing the electrical energy to generate the compensation voltage, it is possible to protect the compensation device by preventing excessive current from being rapidly charged in the voltage storage means (supercapacitor).

1 is a block diagram showing the configuration of the instantaneous voltage drop compensation device of the present invention.
Figure 2 is a circuit diagram showing the configuration of the instantaneous voltage drop compensation device of the present invention.
FIG. 3 is a flowchart illustrating a process of controlling a supply of compensation electricity during a voltage drop in the control unit according to the present invention.
FIG. 4 is a flowchart illustrating a restoration control process after an instantaneous voltage drop made by a controller in the present invention. FIG.
Fig. 5 is a table showing bypass timing in bypass protection operation according to the present invention.

The configuration and operation of the instantaneous voltage drop compensation device of the present invention will be described with reference to the embodiments shown in FIGS. 1 to 5.

1 is a block diagram showing the configuration of the instantaneous voltage drop compensation device of the present invention, Figure 2 shows an example of an implementation circuit diagram of the instantaneous voltage drop compensation device of the present invention.

In order to compensate for the instantaneous voltage drop, the system power switch unit 10 to cut off the grid input voltage and the protection circuit caused by the failure are operated to perform the instantaneous power failure when performing the bypass operation to supply the grid voltage directly to the load side. Instantaneous power failure prevention switch unit 20 for preventing, bypass switch unit 30 for supplying the system power directly to the load in order to protect the circuit from malfunction of the equipment or load overcurrent, and super capacitor from the system input voltage A voltage compensation unit 40 for charging electrical energy to the electric power and supplying the load to the load with the same phase-synchronized voltage as before the voltage drop to the load, and detecting the grid input voltage and dropping the voltage from the detected voltage. (DIP) and instantaneous voltage drop detection unit (50) for detecting power recovery, a control power supply unit (60) for supplying control power from the system input power source, and The control power abnormality detection unit 70 that determines whether the control power supplied to the fisherman 130 is abnormal, and the PWM output unit for charging the compensating voltage supply unit 40 and outputting the inverter voltage under the control of the controller 130. 80), the charge voltage detector 90 for detecting the charge voltage of the compensation voltage supply unit 40 to detect the low charge voltage, and the compensation current from the compensation output provided from the compensation voltage supply unit 40 to compensate Compensation current detector 100 for detecting an overcurrent, an output current detector 110 for measuring the output current supplied to the load, and detects the output overcurrent and the harmonic components by the load, and a compensation voltage supply unit 40 The voltage compensation unit 120 for detecting the compensation voltage from the compensation output supplied to the load from The power supply is cut off, the phase voltage synchronized with the normal system voltage is supplied to the load through the compensation voltage supply unit 40, the compensation current is monitored, and the compensation operation is prevented to prevent damage to the device due to malfunction of the compensation operation. Control unit 130 for performing the bypass control and notification notification to the administrator through the notification alarm means 140, and notification alarm to inform the administrator of the occurrence of accidental voltage drop protection device under the control of the controller 130 Means 140.

In this invention,

The compensation voltage supply unit 40 is a means for generating a compensation voltage for supplying the load with the same phase-locked voltage as before the voltage drop to the load during the instantaneous voltage drop to the load.

The compensation voltage supply unit 40 is a supercapacitor (EDLC) (41) for storing the grid input voltage, a precharger (42) for controlling the initial charging of the supercapacitor 41, and the supercapacitor 41 Compensation control power supply 43 for charging and storing energy and supplying control power with electric energy stored in the supercapacitor (EDLC) 41 when the instantaneous voltage drop occurs, and the supercapacitor 41 when the instantaneous voltage drop occurs. Compensation voltage generation unit 44 for supplying a phase-synchronized voltage equal to the normal grid voltage to the load by converting the electrical energy stored in the load and charging the electrical energy from the grid input power to the supercapacitor 41, and generating the compensation voltage A resonance filter unit 45 for converting the PWM voltage output through the unit 44 into a sine wave power source, a second current transformer CT2 for detecting the compensation current output through the compensation voltage generation unit 44, and compensation Supplied through the voltage generator 44 It is configured to include a voltage transformer 46 for transforming the voltage to supply the load.

Here, the supercapacitor (EDLC) 41 is a storage means for storing the electrical energy for the instantaneous voltage drop compensation.

The precharge unit 42 is to prevent the breakage of the converter for charging the voltage compensation supply unit by a large amount of overcurrent during initial charging, the device is installed in the initial charge and long-term operation It includes a precharge circuit that can be precharged to a predetermined normal voltage (about 80%) upon restart after shutdown.

The compensation control power supply unit 43 is a means for supplying the control power supplied to the control unit 130 when a momentary power failure occurs. When the power failure occurs, the control power supply of the control power supply unit 60 stops supplying control power. It is a power supply device configured for the instantaneous power failure compensation (SAG) for supplying, and is a means for supplying the control power even when the control power supply is not possible due to an abnormality (breakdown) of the control power supply unit 60.

The compensation control power supply 43 is a power supply means (SMPS) for supplying control power with electrical energy stored in the supercapacitor 41, and is composed of a DC-DC converter for DC input.

The compensation voltage generation unit 44 is a means for supplying the load with the phase-locked voltage equal to the normal grid voltage when the instantaneous voltage drop occurs, and converts the electrical energy stored in the supercapacitor 41 and the normal grid voltage. And an inverter for supplying the load with the same phase-synchronized voltage and a converter for charging electric energy in the supercapacitor.

The resonance filter unit 45 is configured as an LC resonance filter for making the PWM voltage output through the compensation voltage generator 44 into a sine wave.

The second current transformer CT2 is a means for detecting a compensation current supplied to a load.

The voltage transformer 46 is configured as an associated transformer for boosting 220V to a voltage to be supplied to the load by a low voltage supplied through the compensation voltage generator 44.

In addition, the present invention, the switch means for disconnecting the grid input power from the load and the control unit 130 for controlling the switch means and the compensation voltage supply unit 40, the instantaneous voltage drop detection and the load according to the instantaneous voltage drop Detection means for providing measurement information to the control unit 130 to stably supply the sinusoidal output that is phase-locked with the normal system power is configured.

The system power switch unit 10 is a means for shutting off the system voltage when the system voltage drops, and is a means for shutting off the main system power supplied to the load.

The momentary power failure prevention switch unit 20 is a means for preventing occurrence of momentary power failure due to switch switching when a bypass operation for directly connecting a grid input power and a load when a protection and failure of equipment occurs when an overcurrent occurs. Switch means to smoothly supply grid input power to the load.

The bypass pass switch unit 30 is a switch means for protecting a circuit due to an operation stop state or an error in the compensation voltage supply operation against an instantaneous voltage drop, and may perform a compensation voltage supply operation even when a system power is input. It is a means to supply the grid input power directly to the load if there is no.

The instantaneous voltage drop detection unit 50 is a means for detecting the instantaneous voltage drop (DIP) and the recovery from the grid input power supply, and the instantaneous voltage drop from the grid voltage according to an instantaneous voltage drop (DIP) determination algorithm registered therein. Judge.

 The instantaneous voltage drop detection unit 50 includes a transformer PT1 for monitoring the grid input power, an input voltage detector 51 measuring the voltage of the grid input power by real-time monitoring of the grid input power through the transformer PT1, and A frequency detector 52 for detecting the frequency of the grid input power supply voltage, a phase detector 53 for detecting the phase of the grid input power supply voltage, and an instantaneous voltage drop determination unit for determining the instantaneous voltage drop based on the measured input voltage ( 54).

The instantaneous voltage drop determination unit 54 compares the stored normal grid input voltage with the currently input grid input voltage to determine the instantaneous voltage drop DIP in preparation for a phase change for a predetermined time.

The control power supply unit 60 is a means for supplying the control power of the control unit 130, it is composed of a power supply (SMPS) for generating and supplying the control power from the system input power.

The control power failure detection unit 70 is a means for determining whether or not the control power failure.

The PWM output unit 80 supplies a pulse width modulation control pulse to the compensation voltage generation unit 44 under the control of the controller 130 to perform an inverting or converting process. Driving means.

The charging voltage detector 90 is a means for detecting the charging voltage of the supercapacitor 41.

The compensation current detector 100 is inverted and output from the compensation voltage generator 44 to receive the current detected from the second current transformer CT2, and the compensation current detection means for detecting the compensation current and the detected compensation. Compensation overcurrent detection means for determining whether the compensation current is overcurrent from the current.

The output current detector 110 includes an output overcurrent detection means for measuring an output current supplied to a load and detecting an output overcurrent, and a harmonic component detection means for extracting harmonic components by the load. The first current transformer CT1 to be measured, the output current measurement unit 111 for detecting the output current by measuring the output current with the current measured from the first current transformer CT1, and the first current transformer CT1 Harmonic component detection unit 112 for extracting harmonic components from the output current.

The compensation voltage detection unit 120 is a means for detecting an inverting voltage from the compensation voltage supply unit 40, a transformer PT2 for detecting a voltage output from the compensation voltage supply unit 40, and a transformer PT2. Inverter voltage detection unit 121 for detecting the inverting voltage output from the compensation voltage supply unit 40 through).

When the instantaneous voltage drop is detected through the instantaneous voltage drop detection unit 50, the control unit 130 switches off the grid power supply unit 10 to switch off the grid input power and control the compensation voltage supply unit 40 to control the normal grid voltage. It provides a process for supply control of the phase-locked voltage to the load.

The control unit 130,

Means for managing and storing input voltage, frequency, and phase values input from the instantaneous voltage drop detection unit 50, and when the instantaneous voltage drop detection is confirmed from the instantaneous voltage drop detection unit 50 by the instantaneous voltage drop detection unit 50, the compensation voltage A means for operating the supply unit 40 to supply the compensation voltage to the load, a means for turning off the system power switch unit 10 to cut off the system input power from the load, the compensation current detection unit 100 and the output current detection unit 110 Means for performing the bypass protection operation of the device by stopping the compensation operation by checking whether the compensation current and the load output current are overcurrent from the moment, and turning on the bypass switch unit 30, and recovering from the instantaneous voltage drop detection unit 50. If this is detected, a phase-synchronized voltage equal to the restored grid input voltage is generated by the compensation voltage supply unit 40, the grid power switch unit 10 is turned on to connect the grid input power to the load, and then normal operation is performed. When the means for stopping the supply of the compensation voltage generating compensating voltage supply (40).

The means for supplying the compensation voltage to the load is a compensation for removing harmonic components when the harmonic components are detected from the harmonic component detection information provided from the inverter voltage and the output current detector 110 from the compensation voltage detector 120. And means for performing a stable compensation voltage generation control by operating and supplying a perfect sinusoidal output to the load.

In addition, the notification alarm means 140 is configured as an alarm or display means is configured so that the user can recognize the failure information.

Referring to the operation process and its operation of the instantaneous voltage drop compensation device having such a configuration as follows.

The transformer PT1 is transformed into a voltage for determining the grid input power. Accordingly, the input voltage detector 51 measures the voltage of the grid input power, and the frequency detector 52 detects the frequency of the grid input power. The phase detector 54 detects the phase.

The voltage, frequency, and phase of the detected grid input power are stored in the controller 130. This is to generate a compensation value when the voltage sag occurs.

The instantaneous voltage drop determination unit 54 determines the instantaneous voltage drop (DIP) and recovery from the voltage of the system input power supply.

The controller 13 controls the compensation voltage supply unit 40 for immediate voltage compensation when the instantaneous voltage drop DIP is detected from the instantaneous voltage drop determination unit 54 to the voltage and frequency when the grid input voltage is normal. The phase synchronization is generated to generate a compensation voltage, and the grid power switch unit 20 is turned off to cut off the load from the grid input power and supply the generated compensation voltage to the load.

That is, the voltage, phase, and frequency are detected and stored in the PLL circuit composed of the frequency detector 52, the phase detector 53, and the phase detector 53 using the voltage detected from the grid input power through the transformer PT1. When the voltage drop is detected, an inverting control signal is generated from the stored voltage, phase, and frequency to compensate for the voltage drop.

As such, when the instantaneous voltage drop is detected, the controller 130 outputs an inverter output control signal according to the voltage, frequency, and phase of the stored system input power, and the PWM output unit 80 accordingly compensates the voltage generation unit 44. The drive signal PWM of the inverter means is output.

Accordingly, the compensation voltage generator 44 inverts the electrical energy stored in the supercapacitor 41 to generate a compensation voltage, and the generated compensation voltage is a sine wave through the resonance filter 45 to convert the voltage into a voltage transformer 46. ) Is transformed into AC 220V of grid input power and frostbite and output to load. At this time, the system power switch unit 20 is disconnected from the system input power.

On the other hand, in supplying the compensation voltage to the load through the inverting operation according to the instantaneous voltage drop as described above, the control unit 130 and the load side harmonic component information from the output current detector 110 and the compensation voltage detector 120 and Harmonic compensation is performed by receiving inverting voltage information to provide distortion free compensation voltage through stable inverting.

When the compensation voltage is supplied by the inverting operation according to the instantaneous voltage drop detection, the load current is measured through the first current transformer CT1, and the output overcurrent detector 111 determines whether the load current is overcurrent and provides it to the controller 130. The harmonic component detection unit 112 extracts the harmonic components by the load and provides the extracted harmonic components to the controller 130.

The control unit 130 accordingly outputs a PWM control signal to the PWM output unit 80 so that the voltage can be stably supplied to the load end. When the harmonic component is detected by the load in the harmonic component detection unit 112, In the PWM control, the output harmonic compensation is performed to compensate the harmonics so that the voltage is supplied to the load stage more stably.

The controller 34 generates an instantaneous voltage drop and turns off the system power switch unit 10 while supplying the compensation voltage to the load side as described above to cut off the system input power.

3 is a flowchart illustrating a compensation voltage supply process performed by the controller 130 when an instantaneous voltage drop occurs.

Subsequently, in the instantaneous voltage drop determination unit 54, when the grid input voltage is measured to be higher than the previous normal grid input voltage and the resetting voltage set value (typically 95%), it is determined as regeneration, and the controller 130 is notified. In operation 130, a power recovery operation is executed when a power recovery is detected.

The controller 130 first measures the voltage, frequency, and phase at the grid input power, makes a synchronized output from the controller 130 to the grid input power, turns on the grid power switch 10, and then turns on the grid power. After connecting to the load side, the inverting operation of the compensation voltage generator 44 is stopped.

After that, the voltage of the supercapacitor 41 is checked from the charging voltage detector 90, and when the voltage of the supercapacitor 41 is detected as a low voltage compared to the set reference voltage, the controller 130 generates a compensation voltage generator 44. ) To charge the supercapacitor 41 to prepare for the next DIP generation compensation.

The supercapacitor 41, which stores the electric energy for compensation, repeats charging and discharging as described above, and is charged through the precharging process by the precharge unit 42.

4 illustrates a restoration process performed by the controller 130.

When charging starts by converting the compensation voltage generation unit 44 during initial charging to the supercapacitor 41, when a large amount of overcurrent flows, the power element of the compensation voltage generation unit 44 may be damaged. Alternatively, when re-operation is performed in a state in which the operation is stopped for a long time, the controller 130 controls the precharge unit 42 to perform precharge to the supercapacitor 41.

The controller 130 controls the charging to be charged to about 80% of the normal voltage of the supercapacitor 41 through the precharger 42.

As described above, the supercapacitor 41 charged to 80% by precharging as described above is charged to 100% by converting the compensation voltage generator 44.

As described above, when an abnormality or an instantaneous power failure occurs in the control power supply unit 60, the control power is not supplied from the control power supply unit 60 to the control unit 130. When the abnormal voltage is detected by monitoring the voltage of the power supply unit 60, the control power is supplied from the compensation control power supply unit 43 of the compensation voltage supply unit 40 to the controller 130.

Meanwhile, in order to protect the device, the controller 130 turns on the bypass switch unit 30 and stops the compensation voltage supply operation when an output overcurrent is detected or an inverter overcurrent is detected during compensation.

That is, when the overload current is detected from the output overcurrent detector 111 or the overcurrent occurs in the compensation current detected by the compensation current detector 100, the bypass protection operation is immediately performed.

As such, while stopping the compensation operation, the controller 130 outputs the failure information through the notification alarm means 140 to the display means or generates an audible alarm to notify the manager.

In general, the hardware is designed so that the bypass protection operation is performed in the shortest time when the output overcurrent exceeds 800% of the rating and the inverting compensation overcurrent exceeds 200% of the rating.

When the bypass switch unit 30 is turned on in order to connect the main bypass line with the load side as described above, the bypass switch unit 30 is a magnet switch and the operation is completed after a predetermined time (about 20 ms or more). The grid input power is connected to the output load through the bypass line.

In this case, as shown in FIG. 5, since the momentary power failure occurs, the momentary power failure prevention switch unit 20 is turned on to prevent the momentary power failure to prevent the momentary power failure to the output load.

That is, when the compensation operation is stopped and the bypass protection operation is performed as described above, the control unit 130 simultaneously turns on the bypass switch unit 30 and the momentary power failure prevention switch unit 20, and then the bypass switch unit. When the 30 is completely connected, the momentary power failure prevention switch unit 20 is turned off to prevent the occurrence of an instantaneous power failure on the load side.

In general, the bypass switch unit 30 is completely connected after about 50 ms after the on operation, and is designed in consideration of this.

On the other hand, the present invention can be represented as the execution process of the instantaneous voltage drop compensation method as follows.

An input voltage storing process of detecting an input voltage, frequency, and phase of a grid input power supply, and storing the detected input voltage, frequency, and phase;

An instantaneous voltage drop detection process for detecting an instantaneous voltage drop against a grid input voltage and a voltage of a current input voltage for a set period, and detecting recovery after an instantaneous voltage drop;

When the instantaneous voltage drop is detected through the instantaneous voltage drop detection process, a compensation voltage supply process of generating a compensation voltage by inverting the voltage, frequency, and phase stored in the compensation voltage supply unit, and inverting the voltage, frequency, and phase;

A system input power interruption process of shutting off a system input power connected to a load when an instantaneous voltage drop is detected through the instantaneous voltage drop detection process;

A compensation operation determination process of detecting a compensation current and a load current supplied to the load and determining whether the compensation voltage is normally supplied from the detected compensation current and the load current;

If it is determined that the compensation voltage supply operation is not performed normally through the compensation operation determination process, a bypass process of stopping the compensation operation and operating the bypass switch unit to bypass the grid input power;

A restoration process of connecting the system input power to the load by turning on the system power switch unit when the restoration is detected through the instantaneous voltage drop detection process;

When the restoration process is completed, the charging voltage supply unit charges the voltage to the compensation voltage supply unit by checking the charging voltage supply unit.

The method may further include a precharging process in a voltage charging process for generating a compensation voltage of the compensation voltage supply unit.

The pre-charging process may further include a pre-charging process for performing normal charging after pre-charging up to the level set in the voltage charging and storing means of the compensation voltage supply unit when the device is first installed or stopped for a long time and restarted. It features.

In addition, the bypass process may further include a momentary power failure prevention process for operating the momentary power failure prevention switch to prevent a momentary power failure that may occur due to the bypass switch not being directly connected.

In the compensation voltage supply process, harmonics are generated to more stably generate a compensation voltage to be supplied to the load stage by performing an output harmonic compensation for the harmonics compensation from the harmonic component information detected from the compensation voltage and the load. It may further include a compensation process.

Claims (13)

delete The grid power switch unit 10 for switching the grid input voltage during the instantaneous voltage drop, and the momentary power failure prevention switch unit for preventing instantaneous power failure at the load side when the equipment input is stopped and the grid input power is bypassed to the load side. 20), the bypass switch unit 30 for supplying the system power to the load to protect the circuit from the malfunction of the instantaneous voltage drop, and the charging and storing of electrical energy from the system input power supply, Compensation voltage supply unit 40 for supplying the load with the voltage synchronized with the phase before the voltage drop to the load, and detects the grid input voltage and measures the grid input voltage from the detected voltage, and detects the dip (DIP) and recovery The voltage drop detection unit 50, the control power supply unit 60 for supplying the control power from the system input power, and the compensation voltage PWM output unit 80 for charging the charging unit 40 and inverter output, charge voltage detection unit 90 for detecting the charge voltage of the compensation voltage supply unit 40 to detect the charge low voltage, compensation voltage supply unit ( Compensation current detector 100 for detecting compensation overcurrent by measuring the compensation current from the compensation voltage provided from 40) and measuring the output current supplied to the load, and detecting the output overcurrent and measuring the harmonic components by the load. When the instantaneous voltage drop is detected through the output current detection unit 110 and the instantaneous voltage drop detection unit 50, the system power supply switching unit 10 switches off the grid input power and normalizes the compensation voltage supply unit 40. Bypassing the normal voltage that is synchronized with the grid voltage to the load and monitoring the compensation current and the load current to prevent damage to the device due to malfunction of the compensation operation. Control unit 130 for performing the control and notification to notify the administrator through the notification alarm means 140, and notification alarm means 140 for notifying the administrator of the error situation of the instantaneous voltage drop protection device under the control of the controller 130 ),
The compensation voltage supply unit 40 includes a supercapacitor (EDLC) 41 for storing the grid input voltage, a precharger 42 for controlling initial charging of the supercapacitor 41, and a super voltage when a voltage drop occurs. A compensation voltage generation unit 44 for converting electrical energy stored in the capacitor 41 to supply a phase-synchronized voltage equal to the normal grid voltage to the load and charging the supercapacitor 41 with the grid input power, and the compensation voltage Resonance filter unit 45 to make the PWM output output through the generator 44 as a sine wave, and a second current transformer (CT2) for detecting the compensation current and the charging current output through the compensation voltage generator 44 And a voltage transformer 46 for transforming the voltage supplied through the compensation voltage generator 44 and supplying the voltage to the load.
The method of claim 2, further comprising a control power failure detection unit 70 for determining whether or not the control power supplied to the control unit 130,
The compensation voltage supply unit 40 charges and stores a voltage in the supercapacitor 41 and, when an abnormality occurs in the control power, the compensation control power supply 43 for supplying control power with electric energy stored in the supercapacitor (EDLC) 41. The instantaneous voltage drop compensation apparatus, characterized in that further comprises.
The method of claim 2, wherein the compensation voltage generator 44 is a means for supplying a load of a phase-locked voltage equal to the normal system voltage to the load when the instantaneous voltage drop occurs, the electrical energy stored in the supercapacitor 41 An inverter for supplying a phase-synchronized voltage equal to the normal grid voltage to the load, and a converter for charging the grid power supply voltage to the supercapacitor.
delete According to claim 2, The instantaneous voltage drop detection unit 50 is a transformer (PT1) for monitoring the grid input power, the input for measuring the voltage of the grid input power by real-time monitoring the grid input power through the transformer (PT1) The voltage detector 51, the frequency detector 52 that detects the frequency of the grid input power supply voltage, the phase detector 53 that detects the phase of the grid input power supply voltage, and the system that is currently input by checking the measured input voltage. And a voltage drop determining unit (54) for comparing the input voltage and the stored normal grid input voltage to determine a voltage drop (DIP) in preparation for a voltage change for a predetermined time period.
The inverter of claim 6, wherein the compensation voltage supply unit 40 detects the compensation voltage from the voltage supplied to the load. Inverting output from the compensation voltage supply unit 40 through the transformer PT2 and the transformer PT2. It further comprises a compensation voltage detection unit 120 including an inverter voltage detection unit 121 for detecting a voltage,
The output current detector 110 includes a first current transformer CT1 installed at a load output terminal, an output overcurrent detector 111 for measuring an output current with a current measured from the first current transformer CT1, and detecting an output overcurrent. And a harmonic component detector 112 for measuring harmonic components from the output current measured by the first current transformer CT1.
The control unit 130 includes means for outputting a compensation voltage to the load by performing a stable PWM control by removing the harmonic components from the inverter voltage and the harmonic component information detected from the harmonic component detection unit 112. Voltage drop compensation device, characterized in that.
According to claim 2, Means for managing and storing the input voltage, frequency, phase values input from the instantaneous voltage drop detection unit 50, Compensation voltage supply unit when the instantaneous voltage drop detection is confirmed from the instantaneous voltage drop detection unit 50 A means for operating the 40 to supply the compensation voltage to the load, a means for turning off the system power switch unit 10 and the bypass switch unit 30 to disconnect the system input power from the load, and the compensation current detection unit 100 And means for performing the bypass protection operation of the device by stopping the supply of the compensation voltage and turning on the bypass switch unit 30 by checking whether the compensation current and the overload current are overcurrent from the output current detection unit 110. And a means for connecting the grid input power to the load by stopping the supply of the compensation voltage supply unit 40 by turning on the system power switch unit 10 when the recovery from the voltage drop detection unit 50 is detected. It dips compensation device according to claim.
According to claim 7 or 8, wherein the control unit 130 means for supplying the compensation voltage to the load is harmonic component detection provided from the inverter voltage measurement and the output current detection unit 110 from the compensation voltage detection unit 120 And a means for performing a stable compensation voltage generation control by removing the harmonic components when the harmonic components are detected from the information.
delete An input voltage storing process of detecting an input voltage, frequency, and phase of a grid input power supply, and storing the detected input voltage, frequency, and phase;
An instantaneous voltage drop detection process for detecting an instantaneous voltage drop in comparison with a normal grid input voltage before the set period and a current input voltage;
When the instantaneous voltage drop is detected through the instantaneous voltage drop detection process, a compensation voltage supply process of generating a compensation voltage by inverting the frequency and voltage information stored in the compensation voltage supply unit to supply the load to the load;
A system input power interruption process of shutting off a system input power connected to a load when an instantaneous voltage drop is detected through the instantaneous voltage drop detection process;
A compensation operation determination process of detecting a compensation current and a load current supplied to the load and determining whether the compensation voltage is normally supplied from the detected compensation current and the load current;
If it is determined through the compensation operation determination process that the compensation voltage supply operation is not performed normally, the bypass process for bypassing the system input power by operating the bypass switch unit;
A restoration process of connecting the system input power to the load by turning on the system power switch unit when the restoration is detected through the instantaneous voltage drop detection process;
Compensating the charging voltage supply unit charging the electricity to the compensation voltage supply unit by checking the charge storage voltage of the compensation voltage supply unit when the restoration process is completed;
Voltage drop compensation characterized in that it comprises a pre-charge process for pre-charging up to the level set in the electric charge storage means of the compensation voltage supply unit when the device is re-started after the initial installation or long time off operation. Way.
12. The method of claim 11, wherein the bypass process further comprises an instantaneous power failure prevention process for operating the momentary power failure prevention switch part to prevent a momentary power failure that may occur due to the bypass switch part not being directly connected. Voltage drop compensation method.
The method of claim 11 or 12, wherein the compensation voltage supplying process performs a feed forward compensation for harmonic compensation from the harmonic component information detected from the compensation voltage and the load to more stably load the load. And a harmonic compensation process for generating a compensation voltage to be supplied.

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