KR20150018015A

KR20150018015A - Power Supply Apparatus for Electrolysis Ballast Water Treatment System

Info

Publication number: KR20150018015A
Application number: KR1020130094388A
Authority: KR
Inventors: 김대회
Original assignee: 김대회
Priority date: 2013-08-08
Filing date: 2013-08-08
Publication date: 2015-02-23

Abstract

The present invention relates to a power supply for electrolytic water treatment, in which a high-speed rectifying element is connected in series with a switch capable of changing the flow of current so that the flow of the output current is inverted, Therefore, the accumulation deposits on the cathode are automatically cleaned due to the electrolysis process, and the SCR-type phase control rectifier and the IGBT PWM system (50% fixed) high-frequency inverter are used. , So that the peak value of the current is lowered.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a power supply apparatus for an electrolysis type water treatment,

The present invention relates to an electrolytic water supply power supply apparatus, and more particularly, to a water supply power supply apparatus for water treatment, which supplies power to an electrolytic apparatus for sterilizing and disinfecting ship equilibrium water or contaminated water before being discharged to the outside, .

Generally, the electrolytic apparatus in a ship is utilized for disinfection process of water and wastewater treatment process. The disinfection process in ship is used for ship equilibrium water treatment, seawater desalination pretreatment process, and sea chest MGPS (Marine Growth Preventing System), and the wastewater treatment process in ships is contaminated with contaminated oil Water (Bilge Water) is used in the processing device.

In addition, a water purification system for sterilizing and purifying microbes of ship equilibrium water is required. In the water purification system, an electrolysis system in which electricity is supplied to pipes supplied with or discharged from ship equilibrium water to kill microorganisms by electricity, An ozone spraying method for spraying and destroying living things, an ultraviolet ray projecting method in which ultraviolet light emitting devices are installed in pipelines to kill living things using ultraviolet rays, and a chemical method in which chemicals are put into a tank in which ship ballast water is stored, have.

Electrolysis type is the most advantageous than other methods in terms of disinfection rate compared to other methods. However, since the power supply unit that supplies electricity needs to output a large current, the volume of the transformer, semiconductor elements, and cooling radiator becomes large, There is a disadvantage that it can not be mounted on a supply pipe or nearby.

In order to overcome such a problem, conventionally, it is possible to directly mount the pipeline to a pipe with a small volume, thereby improving the efficiency by reducing the length of the electric supply wiring. In addition, it can prevent safety accidents due to corrosion of wiring, Has developed a rectifier.

Such a conventional technique is disclosed in Korean Patent Registration No. 10-1263712.

The full-bridge type switching unit according to the related art has the following problems due to the IGBT PWM control converter method.

FIG. 5 is a circuit configuration diagram of a general rectification type power supply for water treatment similar to the above-described conventional method. The output side choke is difficult to mount in a product because it needs to output a large current. Therefore, in general, only an extremely small inductance is mounted.

5, the reactor L1 suppresses harmonics of the alternating current component to improve the AC input power factor, the AC voltage (3-phase 440 VAC) is rectified through the bridge diode, the DC voltage including the ripple voltage is supplied to the capacitor CAPACITOR, And smoothed. However, since the reactor is located on the side of the AC input, the reactor L1 is in proportion to the magnitude of the input current

And the capacitors, the full-bridge switch, the transformer, and the second-order rectifier diodes D1 and D2 become the maximum voltage at no load and the minimum voltage at full load, which causes a large voltage fluctuation to be applied .

In FIG. 5, the bridge diode serves to rectify an alternating voltage (3-phase 440 VAC) and the range of variation of the rectified DC voltage is input voltage 440 VAC (± 20%) × (0.9 to 1.4142) 747Vdc ', which makes it difficult to optimally design the full-bridge switch, the transformer (TRANS), and the output rectifier diode. In addition, in order to suppress the inrush current flowing into the capacitor when the initial power is turned on, an inrush current prevention circuit composed of a SCR + inrush current limiting resistor is connected in series at the rear end of the bridge diode (BRIDGE DIODE) In the SCR, a conduction loss proportional to the current flowing in the load is continuously generated.

In FIG. 5, the charge / discharge ripple current, which determines the loss and lifetime of the capacitor CAPACITOR, varies according to the duty ratio (D = conduction time / switching frequency period) of the full bridge switch. Depending on the voltage and current, it varies from 0 to 0.5. At 0.25, the maximum ripple current flows through the capacitor. If the duty ratio is close to 0.5 and the full bridge switch can be operated, the capacitor ripple current is minimized and the lifetime and reliability of the capacitor are significantly increased.

In FIG. 5, the IGBT full bridge switch is determined by loss and stress depending on the magnitude of the applied voltage and the conduction current. The magnitude of the IGBT conduction current greatly varies according to the variation range of the rectified DC voltage, the output current, and the output voltage . If the output current maximum average current is 1300ADC and the output voltage operating range is 5 ~ 25VDC, the duty ratio of the full bridge switch is 0.04 when the input maximum voltage is at the input maximum voltage and 0.04, 0.47 for the maximum output voltage at the voltage.

Equation (1) is an input / output voltage equation,

(2) is a minimum duty ratio,

The following Equation 3 is the maximum duty ratio,

In the equations (1), (2) and (3), Vin denotes a rectified DC voltage, Vout denotes a DC output voltage, N1 denotes a primary winding of the transformer, and N2 denotes a secondary winding of the transformer.

Therefore, it can be seen that the duty ratios are changed from a minimum of 0.04 to a maximum of 0.47 from the equations (1), (2) and (3). If the salinity of the sea equilibrium water is increased, it is generally operated at the maximum output current at the minimum output voltage. However, if the salt content is high, the electrolytic disinfection action is not possible unless the maximum output current is applied at the maximum output voltage. can do.

Also, from Equation (2), when the minimum output voltage is 5VDC at the input maximum voltage and the duty ratio D is 0.04, the maximum peak current flowing through the full bridge switch is expressed by the following equation 4, and 5, respectively.

Equation (4) is the full-bridge switch current equation,

Equation (5) is a full bridge switch current calculation equation.

Also, when the maximum output voltage is 25VDC at the maximum input voltage, the duty ratio (D) is 0.47. If the maximum output current has an average value of 1300ADC at this time, the maximum peak current flowing through the full bridge switch is expressed by the following equation .

Therefore, when operating at the minimum duty ratio condition (= minimum output voltage 5VDC), the current size 115A (Peak) when the current flowing in the full bridge switch is 1354A (Peak) and the maximum duty ratio condition ), The current stress applied to the switch increases to a very large value.

5, the duty ratio D is 0.04 when the maximum output voltage is 5VDC at the input maximum voltage and the maximum output current average value 1300ADC flows at the output current rectifying diodes D1 and D2 as shown in the following equations (7) and do.

Equation (7) is an output side rectified diode current equation,

Equation (8) is an equation for calculating the output current of the output-side rectifying diode.

Therefore, when the minimum duty ratio condition (= minimum output voltage 5VDC), the magnitude of the current flowing through the output rectifier diodes D1 and D2 is 16,250A, which is about 12.5 times larger than the output current magnitude 1,300A, It can be seen that the stress increases to a very large value.

The output current of the rectifier shown in FIG. 5 is outputted as an impulse type so that the output current smoothing choke is connected to the final output terminal in order to smooth the current into a flat DC current. However, if the large current and large capacity are not realized, And the weight and volume of the DC power supply device become large, which is a hindrance to commercialization of the device.

If the pulse voltage and current are continuously applied to the electrode of the electrolytic cell, the performance of the electrolysis can be increased. However, since the electrode wear is severely caused, the life of the electrode is shortened, There is a problem in that it causes an economic loss to be made and a reliability is deteriorated.

In addition, since the output current of the prior art shown in FIG. 5 is outputted in a single direction, foreign matter obstructing electrolysis adheres to the electrode of the electrolytic cell when the single-directional operation is performed for a long time.

Therefore, in order to improve the electrolysis efficiency, the electrode of the electrolytic cell must be cleaned. To this end, there is a difficulty in periodically changing the wiring supplied to the electrolytic cell and then re-

Korean Patent Registration No. 10-1263712 (Published on May 13, 2013)

Accordingly, in order to solve the problem of the related art, the present invention provides a high-speed rectifying element connected to a switch capable of changing the flow of current in series so that the flow of the output current is reversed so that the current flows to the electrode in the reverse direction Therefore, it is an object of the present invention to provide an electrolytic water supply power supply apparatus that automatically removes accumulated deposits on a cathode due to an electrolysis process.

Another object of the present invention is to reduce the peak value of the voltage and current applied to each circuit component by using a SCR type phase control rectifier device and an IGBT PWM method (50% fixed) high frequency conversion device.

The electrolytic method power supply for water treatment for achieving the object of the present invention is an electrolytic method in which an input AC power is rectified and supplied to an electrode for electrolysis to electrolyze the ballast water or polluted water to sterilize and disinfect the water, A phase control rectifier for converting the input AC power into phase control and direct current; A high frequency conversion unit for switching the DC power outputted from the phase control rectifying unit to a high frequency and outputting it as a high frequency AC power; A high frequency transformer for converting the AC power output from the high frequency converting unit into an output voltage and a current, as well as electrically insulating the DC power from the DC output; An output rectifying unit for rectifying the high frequency AC voltage and current output from the high frequency transformer to a DC output voltage and a current; An output polarity switching unit for switching the direction of the DC voltage and the current output from the output rectifying unit according to a control signal and supplying the DC voltage and the current to the electrode for electrolysis; And controlling the phase control rectification unit to control the high frequency conversion unit, switching the output polarity of the output polarity switching unit, measuring the output DC voltage and current, And a control / communication unit for monitoring the measured voltage and current value and a status signal of the power supply unit.

The control / communication unit transmits measurement signals and status signals from the respective units to a control computer through an external communication network, or receives control signals from the control computer through external communication networks to control the units, , The high-frequency conversion unit and the output polarity conversion unit, respectively.

The switching element may be a semiconductor switching element formed of an SCR, an insulated gate bipolar transistor (IGBT) or a field effect transistor, or a relay element.

The power supply for electrolytic water treatment according to the present invention connects a switch capable of changing the flow of current in series with the fast rectifying element so that the flow of the output current is reversed so that the current flows in the reverse direction to the electrode , It is possible to automatically clean deposits accumulated on the cathode due to the electrolysis process.

Further, since the present invention utilizes a high-frequency conversion device of the SCR type phase control rectifier and the IGBT PWM method (50% fixed), the peak value of voltage and current applied to each circuit component becomes low, There is an alleviating effect.

1 is a circuit diagram of a power supply apparatus for electrolytic water treatment according to an embodiment of the present invention,
2 is an output waveform diagram for comparison between the prior art and the present invention with respect to the configuration of the phase control rectification section and the high frequency conversion section,
3 is a circuit diagram of an output rectifying unit and an output polarity switching unit according to another embodiment of the present invention,
FIG. 4 is a current flow direction indication diagram switched by the output polarity switching unit in FIG. 1,
5 is a circuit diagram of a conventional electrolytic water treatment rectifier.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A power supply apparatus for water treatment according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

1 is a circuit configuration diagram of a decompression type water treatment power supply device according to an embodiment of the present invention. In order to electrolyze the ballast water or polluted water to sterilize and disinfect the water, A phase control rectifier 110 for removing the ripple components included in the DC voltage output from the phase control rectifier 110 and a first-order A high frequency conversion unit 130 for switching the DC power outputted from the primary filter unit 120 to a high frequency AC power by switching the high frequency power to the AC power outputted from the high frequency conversion unit 130, A high frequency transformer (140) for converting electric power into an output voltage and current in addition to electrical insulation with a direct current output; an output rectifier (150) for rectifying the high frequency AC voltage and current output from the high frequency transformer An output polarity switching unit 160 for switching the direction of the DC voltage and the current output from the output rectifying unit 150 according to a control signal and supplying the DC voltage and current to the electrode for electrolysis, A second filter unit 170 connected to a rear end of the output rectifier unit 160 for removing a ripple component from the current output from the output rectifier unit 150 and a second filter unit 170 for measuring an AC power input to the phase control rectifier unit 110, Controls the control rectification part 110 to control the high frequency conversion part 140, to switch the output polarity of the output polarity switching part 160, to measure the output DC voltage and current, And a control / communication unit 100 for monitoring the current value and the status signal of the power supply unit.

The high-frequency conversion unit 130 includes FETs or IGBT circuits as half bridges S1 and S2 or full bridge S1 to S4 circuits. In case of a half bridge, the control / communication unit 100 sets S1: S2 to 50 %: 50%.

The output rectifying unit 150 is connected to the output polarity switching unit 160 in parallel with the high-speed switching diodes connected in the forward direction and the reverse direction to the secondary coil output terminal of the high-frequency transformer 140.

The output polarity switching unit 160 may be a semiconductor switching device formed of an SCR, an insulated gate bipolar transistor (IGBT), or a field effect transistor, or may be a relay device. Connect in series.

The control / communication unit 100 transmits measurement signals and status signals from the units 100, 110, 130 and 170 to the control computer 10 via an external communication network, And controls the phase control rectification unit 110, the high frequency conversion unit 130, and the output polarity switching unit 160 based on a control signal for controlling the respective units through an external communication network.

The operation of the present invention will be described in detail with reference to FIGS. 1 to 3. FIG.

First, the present invention provides a disinfecting device for an electrolytic method for sterilizing and disinfecting ship equilibrium water to prevent ecosystem disturbance and pollution, or disinfecting microorganisms before discharging other polluted water to the outside, When the single-phase or three-phase AC power is phase-regulated and rectified to DC power, the converted DC power is converted into a high-frequency AC through a high-frequency conversion and a transformer, and then rectified through a rectifier to be supplied to an electrode in the electrolyzer. The polarity of the power source is converted according to the control signal to remove the deposit attached to the electrode for electrolysis.

The single-phase or three-phase AC power input to the phase control rectification unit 110 of the power supply unit is measured by the control / communication unit 100.

The phase control rectification unit 110 includes an SCR and a diode. The control / communication unit 100 converts the input AC power to DC power through phase control of the SCR.

The voltage / current output from the phase control rectification unit 110 includes an inductor and a capacitor for eliminating the ripple component of the voltage in the first filter unit 120 and securing a hold-up time.

The high-frequency transformer 130 receives the stable DC power through the primary filter 120 and switches the high-frequency AC power to a high-frequency power. The high-frequency transformer 140 transforms the high- And a high-frequency core for converting AC input power into an output voltage and current, and a primary coil.

The output rectifying unit 150 is composed of a high-speed switching diode and rectifies the alternating voltage and the current output from the high-frequency transformer 140 to a direct current.

The DC voltage and current output from the output rectifying unit 150 are supplied to the electrodes of the electrolytic cell after removing ripple components included in the current through the secondary filter unit 170 formed of an inductor.

At this time, the control / communication unit 100 controls the output polarity switching unit 160 to switch the polarity of the DC power output from the output rectifying unit 150, so that the current flows in the reverse direction, Thereby removing accumulated deposits.

The control / communication unit 100 measures the AC input power, generates a trigger signal of the phase control rectifier unit 110 configured by SCR and a PWM (Pulse Width Modulation) signal of the high frequency conversion unit 130, Controls the switching of the polarity of the output, measures the voltage and current of the DC output, monitors the machining state in the power supply, and transmits it to the control computer 10 through the external communication terminal.

The phase control rectification unit 110 includes an SCR bridge and includes a first filter unit 120 for generating a first DC output voltage by phase-controlling an input AC voltage and filtering the first output voltage, The voltage and current stress applied to the components of the high-frequency transformer 130, the high-frequency transformer 140, the output rectifier 150, the secondary filter 170, and the output polarity switching unit 160 are minimized, So that the primary DC output voltage is controlled in proportion to the secondary output voltage and current.

The control / communication unit 100 uses the 50% fixed converter method for the SCR phase control of the phase control rectification unit 110 and the PWM pulse width of the high frequency conversion unit 130. [

More specifically, if the input voltage is 340V and the phase control rectifier 110 is configured as a 3-phase full bridge, the control / communication unit 100 outputs the output voltages of the phase control rectifier 110, 400V) is calculated and outputted by the control / communication unit 100 as shown in the following Equation (9).

Where VDC is the phase control rectified section output voltage, Vac is the three-phase AC input voltage,

Vout is the DC output voltage, D is the duty ratio of the high frequency transformer, and N1 and N2 are the transformer primary and secondary windings.

And the final output voltage of the power supply is calculated by the following equation (10).

Here, VDC is the phase control rectification output voltage, D is the duty ratio of the primary applied voltage of the transformer, N1 is the primary winding of the transformer 12T, and N2 is the secondary winding of the transformer 1T.

The fixed ratio D (0.5) when the output voltage calculated by Equation (10) is 25VDC, the IGBT applied voltage and thus the peak current, and the fast switching diode applied reverse voltage and peak current of the output rectifier 150 satisfy the following equation 11-14.

If the output voltage is 5VDC, the fixed ratio D (0.5), the IGBT applied voltage and peak current of the high frequency converter 130 and the reverse voltage and peak voltage applied to the fast switching diode of the output rectifier 150 The current is calculated by the following equations (15) to (18).

Therefore, the SCR control + IGBT rectification method of the phase control rectification unit 110 is similar to that of the conventional diode full wave rectification and IGBT PWM control rectification method. The voltage and current applied to the IGBT and the output rectification diode are shown in Tables 1 and 2 The same effect can be obtained.

Table 1 below shows the case of output voltage / current = 25V / 1300A,

division IGBT maximum voltage IGBT peak current DIODE reverse voltage DIODE peak current IGBT PWM (conventional) 747V 115V 125V + surge 4,062A SCR + IGBT (improvement) 300V 108A 50V + surge 1,300A

Table 2 below shows the case where the output voltage / current = 5V / 1300A.

division IGBT voltage IGBT peak current DIODE Voltage DIODE peak current IGBT PWM (conventional) 747V 115V 125V + surge 16,250A SCR + IGBT (improvement) 60V 108A 10V + surge 1,300A

The first and second rms values of the IGBT and the high frequency transformer 140 through which the square wave current flows in accordance with the on / off state of the IGBT of the high frequency converter 130 are changed according to the duty ratio as shown in the following equation (8) When the duty is reduced, the peak current is increased, and the IGBT switching loss and the coil and core loss of the transformer become larger.

Therefore, if the applied voltage of the IGBT is controlled by the SCR and the duty of the square wave current is kept at 0.5, it is possible to operate with the smallest peak current, thereby reducing the stress applied to the component and maximizing the efficiency .

2 shows the input / output voltage and current waveforms of the conventional method (diode + IGBT control) and the method according to the present invention (SCR + IGBT control). In order to increase the electrolysis effect of water in a conventional rectifier, A large filter inductor is required. However, in the control method according to the present invention, the output current has a very short downtime, so that a filter inductor is rarely needed.

That is, the voltage and current stresses of the IGBT and the transformer of the conventional rectifier are very high, and the stress of the IGBT and the transformer voltage and current of the rectifier according to the present invention is very low.

Also, when comparing the DC output voltage and the current, the DC output voltage and the current according to the present invention output a voltage and a current close to DC, while the conventional method fluctuates in a pulse type having a dwell time.

3 is a circuit diagram of an output rectifying unit and an output polarity switching unit according to another embodiment of the present invention. The output rectifying unit 150 connects high-speed switching diodes to both ends of a secondary coil of the high-frequency transformer 140 And a switching element is connected to a common line of the output terminal of the high-speed switching diode and the secondary coil by a bridge circuit.

The switching device constituted by the bridge circuit may be constituted by SCR, IGBT or FET which is a semiconductor element, or it is constituted by a relay element.

The control / communication unit 160 drives the switching device formed of the bridge circuit to switch the direction of the current flowing through the output rectifying unit 150, so that the polarity of the electrode in the electrolytic bath is reversed.

4 is a graph showing the flow of current due to the switching of the output electrode according to the embodiment of the present invention. As shown in FIG. 4, the control / communication unit 100 controls each SCR So that the direction of current flow is switched in the forward direction or the reverse direction as shown in FIG.

That is, since the electrode polarity (+) (-) in the electrolytic cell is switched by each SCR on / off control of the output polarity switching unit 160, accumulation adhered to the electrode (- Out.

Since the polarity of the electrode is switched at a constant cycle in this way, accumulated deposits on the electrode (-) can be removed.

As described above, the present invention has been described by reference to the preferred embodiments and drawings, but it should be understood that the present invention is not limited to these embodiments, and various changes and modifications may be made without departing from the spirit and scope of the present invention by those skilled in the art. It will be understood by those skilled in the art that various changes and modifications may be made without departing from the scope of the appended claims.

100: control computer 100: control / communication unit
110: phase control rectifying unit 120: primary filter unit
130: high frequency conversion unit 140: high frequency transformer
150: output rectifying section 160: output polarity switching section
170: Secondary filter section

Claims

An electrolytic water treatment power supply apparatus for rectifying input AC power to electrolyze water for sterilizing and disinfecting ship equilibrium water or polluted water and supplying it to an electrolysis electrode,
A phase control rectifier for converting the input AC power into phase control and direct current;
A high frequency conversion unit for switching the DC power outputted from the phase control rectifying unit to a high frequency and outputting it as a high frequency AC power;
A high frequency transformer for converting the AC power output from the high frequency converting unit into an output voltage and a current, as well as electrically insulating the DC power from the DC output;
An output rectifying unit for rectifying the high frequency AC voltage and current output from the high frequency transformer to a DC output voltage and a current;
An output polarity switching unit for switching the direction of the DC voltage and the current output from the output rectifying unit according to a control signal and supplying the DC voltage and the current to the electrode for electrolysis; And
A phase control rectifying unit for controlling the phase control rectifying unit, controlling the high frequency converting unit, switching the output polarity of the output polarity switching unit, measuring the output DC voltage and current, And a control / communication unit for monitoring the measured voltage and current value and the status signal of the power supply unit.

The method according to claim 1,
Further comprising a first filter unit for removing a ripple component included in a DC voltage input from the phase control rectifying unit to the high frequency converting unit and for securing a hold up time, Device.

The method according to claim 1,
The phase control rectifier unit may include an SCR (Silicon Controlled Rectifier) bridge for generating a primary DC output voltage by phase-controlling the input AC voltage,
Wherein the high-frequency conversion unit includes an IGBT (Insulated Gate Bipolar Transistor) of a PWM control method.

The method of claim 3,
Wherein when the SCR of the phase control rectification unit is composed of a three-phase full bridge SCR, the phase control output voltage is outputted in proportion to the final output voltage and the output current.

The method of claim 3,
Wherein the high-frequency conversion unit generates an output voltage by fixing the pulse width of the PWM control method to 50%.

The method according to claim 1,
Further comprising a secondary filter unit connected to a downstream end of the output polarity switching unit to remove a ripple component from a current output from the output rectifying unit. Supply device.

The method according to claim 1,
Wherein the output rectifying unit is connected in parallel to a high-speed switching diode in a forward direction and a reverse direction in a secondary coil output terminal of the high-frequency transformer, and is connected to the output polarity switching unit.

8. The method of claim 7,
Wherein the output polarity switching unit comprises a switching device connected to the high-speed switching diode as a series connection or a bridge circuit.

9. The method of claim 8,
Wherein the switching element is a semiconductor switching element composed of one of an SCR, an insulated gate bipolar transistor (IGBT), and a field effect transistor, or is a relay element.

The method according to claim 1,
The control / communication unit may transmit the measurement signal and the status signal from the respective units to a control computer through an external communication network or receive a control signal from the control computer through an external communication network to control the units, And the output polarity switching unit are respectively controlled by the control unit.