TITLE OF THE INVENTION
"Constant Current ballast control PCB for UV based water purifier"
FIELD OF THE INVENTION
The present invention relates to a water purification system, more particularly to a water
purification system comprising an electronic TRIAC based voltage and current regulating
circuit to power a UV radiation based germicidal system within the said water purification
system.
OBJECTIVE OF THE INVENTION
It is an objective of the present invention, to provide a new and improved apparatus for
purification of water which increases the efficiency of a radiation system to eradicate
pathogens within said water purification system.
It is a further objective of the invention, to provide the said apparatus which includes an
electronic ballast circuitry to provide a constant flow of current to the radiation system in
the said water purification system.
It is a further objective of the invention, to provide the said apparatus with a system
wherein, the constant flow of current provided by the electronic TRIAC control circuitry
ensures a uniform radiation output within the said water purification system.
It is a further objective of the invention, to provide water purification system comprising an
electronic TRIAC based voltage and current regulating circuit to power an Ultra Violet (UV)
radiation based germicidal system within the said water purification system.
RELEVANT PRIOR ART OF THE INVENTION
Water purification is a process of removing undesirable contents such as chemicals,
biological contaminants, suspended solids and gases and so on from water, so as to make
water suitable for drinking purpose. Household water treatment systems have gained
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widespread popularity, particularly in areas with less-than-ideal potable water. A household
system or unit is mounted on a single tap to selectively treat water flowing through the tap.
Treatment may include filtration, irradiation, or both. The most effective water treatment
systems include ultraviolet (UV) irradiation to sterilize the water stream. It is well known
that such UV treatment kills bacteria and viruses with an extremely high degree of
reliability. The water to be treated is routed through a container, and a UV light source
within or adjacent to the container directs UV light through the water stream.
In the UV treatment, in order to kill the micro-organisms in the contaminated water, a
specific quantity or level of ultra-violet radiation is to be maintained. Ultraviolet germicidal
irradiation is a disinfection method that uses ultraviolet (UV) light at sufficiently short
wavelength to kill microorganisms. It is used in a variety of applications, such as food, air and
water purification. The UV light source used in this method is a low intensity UV tube light
that is powered by either from AC current source or DC current source for ultraviolet
germicidal irradiation. Any power fluctuations in the input AC voltage may damage the UV
light source within the water purification device. Hence, for proper functioning of the
system, a constant input power supply is to be provided at the input of the water
purification system.
In few existing methods for providing the power to a UV light source within a water
purification device involves the conversion of the traditional AC voltage to a constant DC
voltage. This DC voltage is allowed to pass through a DC Ballast and is converted back to AC
in order to make UV tube light resistant to voltage fluctuations. This method has the
advantage of improving the life of the UV tube. Further, this method has a disadvantage of
converting the AC voltage to DC voltage and back to AC, which truly depends on the
efficiency of the rectifier used for the conversion and further dependent on the number of
passive and active components used in the conversion process.
ABSTRACT OF THE INVENTION
The present invention pertains to water purification system comprising an electronic TRIAC
based voltage and current regulating circuit to power a UV radiation based germicidal
system within the said water purification system. The system further comprises a water
input system, a power supply and control module, a Purification module, a storage system
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and a water output system. The power supply and control module comprises an
electromagnetic interference (EMI) filter and surge protection module, a power supply
switching section module, a phase angle control module, a CPU control module.
The present invention discloses a method and apparatus for using an electronic AC ballast
circuit that powers the germicidal Ultra violet tube. The method discloses a circuit, to
eliminate high voltage spikes and surges and allow the radiation tube to function effectively.
A microcontroller is used to control the phase angle of the raw AC mains flowing into the
electronic ballast for the germicidal UV lamp for limiting the current and voltage irrespective
of the fluctuating input voltage. When the said water purification device is powered on, the
microcontroller reads the level of input AC voltage using an analog to digital technique and
compares it to a reference value stored inside its memory. It then determines the AC voltage
present at its input and regulates the triggering of the said TRIAC that allows the set AC
voltage to flow into the electronic ballast for providing constant power to said UV radiation
tube which increases the efficiency of a radiation system to eradicate pathogens within said
water purification system.
BRIEF DESCRIPTION OF THE FIGURES
The embodiments herein will be better understood from the following detailed description
with reference to the drawings, in which:
FIG. 1 illustrates a general block diagram of water purification device, as disclosed in the
embodiments herein;
FIG. 2 is a block diagram that illustrates various blocks present in the UV water purification
system, as disclosed in the embodiments herein;
FIG. 3 is a block diagram that illustrate various components of the ballast switching module,
as disclosed in the embodiments herein; and
FIG. 4 illustrates internal circuit diagram of the ballast switching module, as disclosed in the
embodiments herein.
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DETAILED DESCRIPTION OF EMBODIMENTS
The embodiments herein and the various features and advantageous details thereof are
explained more fully with reference to the non-limiting embodiments that are illustrated in
the accompanying drawings and detailed in the following description. Descriptions of wellknown
components and processing techniques are omitted so as to not unnecessarily
obscure the embodiments herein. The examples used herein are intended merely to
facilitate an understanding of ways in which the embodiments herein may be practiced and
to further enable those of skill in the art to practice the embodiments herein. Accordingly,
the examples should not be construed as limiting the scope of the embodiments herein.
The present invention relates to a water purification system comprising an electronic TRIAC
based voltage and current regulating circuit to power a UV radiation based germicidal
system within the said water purification system. The said water purification system
comprises of a water input system, a power supply and control module, a Purification
system, a storage system and a water output system
The water input system further comprises of a Solenoid valve which regulates the water in
flow to the said water purification system. The purification module comprises a water
filtration unit such as pre-filters, post filters, or the like. The purification system comprises
germicidal units such as a UV tube or the like known in the prior art that provides germicidal
activity. The purification module further comprises a ballast switching module.
The Storage system of the said water purification system is a storage unit that stores the
filtered or purified or treated water for consumption. The water output system comprises of
a valve or tap or the like to dispense the purified water from the storage unit.
The power supply and control module comprises an electromagnetic interference (EMI) filter
and surge protection module, a power supply switching section module, a phase angle
control module, a CPU control module. The present invention herein disclose a method and
apparatus which uses an electronic AC Ballast to power a UV tube within the water
purification system. Further, the apparatus disclosed herein eliminates high voltage spikes
and surges to pass through the AC ballast. Referring now to the drawings, and more
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particularly to FIGS. 1 through 4, where similar reference characters denote corresponding
features consistently throughout the figures, there are shown embodiments.
FIG. 1 illustrates a general block diagram of water purification device, as disclosed in the
embodiments herein. As depicted in the figure, the water purification device 100 comprises
a power supply and control module 101, a purification module 103, a storage module 104
and a water outlet module 105. The power supply and control module 101 of the water
purification device 100 receives input power from an AC power supply and provides a
stabilized output power for functioning of the water purification device 100. The purification
module 103 purifies the water using Ultraviolet (UV) light emitted or generated from an
associated UV tube which emits at sufficiently small wavelengths to kill the pathogens in
water to be treated or purified. The storage module 104 stores the water and pumps out the
water through an outlet. The water outlet module 105 provides the purified water for I
drinking after using germicidal disinfection method inside the purification device.
In a preferred embodiment, an AC ballast mechanism is employed for regulation of power
supply to the water purification device circuit. The water purification device 100 receives an
input AC voltage (VAC) and the received voltage is brought down to a required level to
ensure effective functioning of the ballast before providing it to the AC ballast. Further, the
method eliminates high voltage spikes and surges to pass through the AC ballast prior to
powering the UV tube.
FIG. 2 is a block diagram that illustrates various blocks present in the UV water purification
system, as disclosed in the embodiments herein. As depicted in the figure, the power supply
and control module 101 comprises an electromagnetic interference (EMI) filter and surge
protection module 201, a power supply switching section module 202, a phase angle control
module 203, a CPU control module 204. Further, the purification module 103 comprises a
ballast switching module 205 and a UV tube 206.
The EMI filter and surge protection module 201 is a passive electronic device used for
suppressing the conducted interference found on any signal or power line to prevent surges
from entering into the circuit by suppressing them. The EMI filter 201 works by presenting
significantly higher resistance to higher frequency content. The EMI filter filters or reduces
and/or attenuates the unwanted signal strength, thereby having a minimal effect on other
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components or devices. Furthermore, said EMI filter comprises a low pass design that result
in restriction of the flow of high frequency signals, effectively shorting it to the ground.
The power supply switching section module 202 requires an AC input. This module works
with a varying input AC supply within the range of 140V AC - 300VAC. The power supply
switching section module 202 cuts off, if the voltage fluctuates over the specified voltage
band. Further, the power supply switching section 202 can withstand surges and high
voltage spikes and can also with stand 440V AC.
The phase angle control module 203 provides the input to the ballast switching module 205.
The phase angle control module 203 receives the input AC voltage from EMI filter and surge
protection module 201. This input AC voltage received by the phase angle control module is
in the range of 90V AC to 300V AC. The input AC voltage is provided to a Triode Alternating-
Current (TRIAC) present within the phase angle control module 203, which cuts the voltage
to 140 volts and provides as input to ballast switching module 205. The CPU control module
204 control the entire process of water purification. The CPU control module 204 monitors
front panel switches, visual indicators, solenoid valve to UV ballast control.
The ballast switching module 205 receives the input voltage from the TRIAC and powers the
UV radiation tube 206 within the water purification device. The phase angle control module
203 limits the voltage into the switching section by feeding the input into a TRIAC, thereby
controlling the current flowing into the Ultraviolet lamp.
Since the electronic ballast is being fed from the raw AC mains power, this ballast has to
overcome the challenges of the power fluctuations to provide the stabilized power to the UV
tube within the water purification device. The invention disclosed herein provides a circuit
which eliminates high voltage spikes and surges into the UV tube. Adequate circuit is
provided to protect, control and increase the efficiency of the electronic ballast.
In order to provide a stabilized output to the AC ballast, a microcontroller is used to control
the voltage and current following into the electronic ballast circuit irrespective of the input
RAW AC mains. This RAW AC voltage can be in the range of 140V to 440V.
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The microcontroller controls an electronic component called the TRIAC (Triode AC switch)
which limits the amount of voltage into the circuitry. The technique used here to limit the
voltage into the electronic ballast is called AC phase angle control. The said circuit of
microcontroller along with the TRIAC is present within the phase angle control module 203.
Initially the AC input, which is a sine wave (VAC) is applied to the EMI filter and surge
protection module 201 as shown in the figure 2. The EMI filter module filters and/or
attenuates the AC input, removes the high frequency components and suppresses the surges
within the AC input which is then fed to said phase angle control module 203. The TRIAC
within the phase angle control module 203 receives the AC input. The microcontroller reads
the level of input AC voltage using an analog to digital technique and compares it to a
reference value stored inside its memory. Further, the microcontroller determines the AC
I voltage present at its input and controls the triggering of the TRIAC which allows only the set i
AC voltage to flow into the electronic ballast to power the UV tube 206 within the water
purification device. ;
i
Further, when the input is fed to a TRIAC, the CPU control module 204 senses the input
voltage level and accordingly uses a technique called AC phase angle control to limit the
voltage into the ballast switching module 205 for controlling the current flowing into the UV
tube 206.
The method and apparatus of the present invention ensure that the electronic ballast is not
exposed to the variation in voltage, surges and voltage spikes as experience by other devices
on power lines. The features realized with the use of this technique is higher efficiency and
greater intensity for the given power increased UV germicidal lamp life eliminating false
starts as observed with preheated UV lamps.
FIG. 3 is a block diagram that illustrates various components of the ballast switching module,
as disclosed in the embodiments herein. As depicted in the figure, the internal circuit of
ballast switching module 205 comprises an EMI filter and surge protection module 201, an
AC rectifier 301, and a half bridge inverter 302. An AC mains voltage of 220V with 50HZ
frequency is provided as input to the EMI filter and surge protection module 201 as shown in
the figure. The EMI filter and surge protection module 201 attenuates the AC input, provides
a significantly higher resistance to higher frequency content and suppresses surges present
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in the AC input. The AC mains voltage is then rectified by four rectifying diodes within the AC
V-rectifier 301 to a corresponding DC voltage obtained as an output from AC rectifier 301. The
AC rectifier 301 provides an attenuated DC output to the half bridge rectifier 302, which
provides power to the UV tube 206. The half bridge inverter 302 is of the voltage fed type
belonging to a group of high frequency resonant inverters, which are very attractive to drive
lamp circuits so that switching losses of the transistors is substantially reduced.
FIG. 4 illustrates an internal circuit diagram of the ballast switching module, as disclosed in
the embodiments herein. As depicted in figure 3, the AC ballast circuit comprises an EMI
filter and surge protection module 201, AC rectifier 301 and a half bridge inverter 302. An AC
mains voltage of 220V with 50HZ frequency is provided as input to the AC rectifier 301. The
AC mains voltage is rectified by four bridge rectifying diodes within the AC rectifier 301 to a
corresponding DC voltage. The four bridge rectifying diodes are D14, D15, D20 and D21 as
shown in figure 4. The AC mains voltage is rectified by four bridge rectifying diodes and
smoothed by the buffer capacitor C42 to get a DC supply voltage for the half bridge inverter.
Further, an EMI filter attenuates high frequencies and prevents surges from entering the AC
rectifier 301 before providing the DC output to the half bridge inverter 302.
The half bridge inverter is of the voltage fed type belonging to a group of high frequency
resonant inverters, which drive lamp circuits so that switching losses of the two switching
transistors Q.5and Q6 as shown in figure 4 is substantially reduced. The half bridge inverter
circuit is of instant-start type to obtain almost immediate light output when the mains
voltage is applied to the circuit.
The startup circuit generates a start pulse and the circuit will generate a high AC voltage
across the igniter capacitor which is connected in parallel with the lamp. Normally, the lamp
will breakdown and the circuit operates in the burn phase.
t The two bipolar transistors need appropriately high gain value in order to guarantee the
correct ignition of the lamp during the startup phase. The Compact fluorescent lamps (CFLs)
usually require about 600 V as peak voltage to strike the arc. Once the arc is established
about 100 V are enough to sustain it while, electrically, the resistance of the lamp falls from
I about one mega ohm down to a few hundred ohm. The lamp is ignited by generating an over
voltage across the capacitor C29 in parallel to the C29-C33-C36 capacitors.
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During the start up phase, the lamp acts as an open circuit and the C29 capacitor imposes
the resonant frequency of the circuit, as C29 is much smaller than the C33-C36 capacitors.
The imposed overvoltage is high enough to ionize almost instantaneously the gas in the
lamp. Once the lamp is lighted, the capacitor C29 acts as short-circuited by the lamp itself
and the natural frequency is determined mainly by the capacitors C33-C36 charged or
discharged through the DC-AC converter. The startup network is represented by the only
resistor R35, connected between the collector and the base of the high side transistor, since
the capacitors in series with the bases act as a high impedance elements during the first
instant of the startup.
Further, Bipolar switching in the resonant circuit have three different operating modes in
normal working conditions namely re-circulating, conduction and transition phases. In the
re-circulating phase, the transistor will not be in conduction state and shifts from a first
inactive state where its B-C junction diode is activated to allow the re-circulation of load
inductor demagnetization current ILP shared with the external diode in anti-parallel to the
device itself, to a second inactive state in which the external diode is turned off. In this
case, both of the two B-E and B-C junctions are forward biased in order to complete the
residual demagnetization of the Lp inductor until the forcing re-circulating current ILP, which
imposes the negative collector current and reaches the zero value.
In the conduction mode, the two B-E and B-C junctions of the transistor continue to be in
forward biased and the bipolar transistor conducts a positive magnetization current for the
inductive load. The turn-off mechanism occurs in three stages.
The storage time, or time spent indicates the time to extract the storage in excess and
recombine the charge stored on the base and the current fall time indicates the time in
which the collector current passes from 90% to 10% of its maximum value, and rise time
represents the time of the collector-emitter rise time and represents a sort of dead time
phase in which both bipolars are substantially inactive since only the B-C and voltage.
Further, the transition mode occurs during the voltage B-E junction capacitances of both
devices are interested in being charged or discharged in reverse bias. This phase anticipates
the re-circulating phase preliminary to the conduction phase of the complementary device.
During the turn-off process, the dynamic operation point of the transistor moves through
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three different operating regions on the current and voltage namely hard saturation region,
^uasi saturation region and active region.
The embodiments disclosed herein can be implemented through at least one software
program running on at least one hardware device and performing network management
functions to control the network elements. The network elements shown in Fig. 1 through 3
include blocks which can be at least one of a hardware device, or a combination of hardware
device and software module.
The embodiments disclosed herein specify an apparatus which uses an AC Ballast to power a
UV tube within a water purification device. The method allows smoothening of the AC input
to power the UV tube within the water purification device and providing a system thereof.
Therefore, it is understood that the scope of the protection is extended to such a program
and in addition to a computer readable means having a message therein, such computer
readable storage means contain program code means for implementation of one or more
steps of the method, when the program runs on a server or mobile device or any suitable
programmable device. The method is implemented in a preferred embodiment through or
together with a software program written in e.g. Very high speed integrated circuit
Hardware Description Language (VHDL) another programming language, or implemented by
one or more VHDL or several software modules being executed on at least one hardware
device. The hardware device can be any kind of device which can be programmed including I
e.g. any kind of computer like a server or a personal computer, or the like, or any I
combination thereof, e.g. one processor and two FPGAs. The device may also include means
which could be e.g. hardware means like e.g. an ASIC, or a combination of hardware and
software means, e.g. an ASIC and an FPGA, or at least one microprocessor and at least one
memory with software modules located therein. Thus, the means are at least one hardware
means and/or at least one software means. The method embodiments described herein
: could be implemented in pure hardware or partly in hardware and partly in software. The
device may also include only software means. Alternatively, the invention may be
implemented on different hardware devices, e.g. using a plurality of CPUs.
The foregoing description of the specific embodiments will so fully reveal the general nature
of the embodiments herein that others can, by applying current knowledge, readily modify
•
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and/or adapt for various applications such specific embodiments witliout departing from tlie
generic concept, and, therefore, such adaptations and modifications should and are
intended to be comprehended within the meaning and range of equivalents of the disclosed
embodiments. It is to be understood that the phraseology or terminology employed herein is
for the purpose of description and not of limitation. Therefore, while the embodiments
herein have been described in terms of preferred embodiments, those skilled in the art will
recognize that the embodiments herein can be practiced with modification within the spirit
' and scope of the claims as described herein.

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CLAIMS
1. A water purification device to purify water by regulating power to a UV radiation
based germicidal system comprising a water input system, a power supply and
control module, a Purification module, a storage system and a water output system.
2. The said power supply and control module as claimed in Claim 1, further comprises
an electromagnetic interference (EMI) filter and surge protection module, a power
supply switching section module, a phase angle control module and a CPU control
module.
3. The purification module as claimed in Claim 1, further comprises a ballast switching
module and a UV tube to purify the input water in the said water purification device.
4. The electromagnetic interference (EMI) filter of the power supply and control
module, as claimed in Claim 2, filters or reduces and/or attenuates the unwanted
signal strength enters via power supplied to the water purification system.
5. The power supply switching section module of the power supply and control module,
as claimed in Claim 2, cuts off input voltage supply over the specified voltage,
wherein the specified voltage is between the ranges of 140VAC - 300VAC.
6. The phase angle control module of the power supply and control module, as claimed
in Claim 2, further comprises a Triode Alternating-Current (TRIAC) which cuts off the
Voltage to the specified range of 140 voltage
7. The ballast switching module of the purification module, as claimed in Claim 2
receives the input voltage from the TRIAC to power said UV radiation tube without
voltage fluctuations within the water purification device
8. The CPU control module of the power supply and control module as claimed in Claim
2, is the microcontroller to monitor the entire process of purification including the
front panel switches, visual indicators, solenoid valve to UV ballast control
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9. The said power supply and control module as claimed in Claim 2, wherein, the input
AC voltage (VAC) and the received voltage is brought down to a required level to
ensure effective functioning of the ballast before providing it to the said AC ballast.
10. A method of water purification of using an electronic TRIAC based voltage and
current regulating circuit to power a UV radiation wherein
a) The water from the source enters via the water input system into the purification
module,
b) The current and voltage passes through the power supply and control module,
wherein the unwanted signal strength in the input power and voltage is reduced
and/or attenuated via the EMI filter,
c) The power and voltage is then passed via power supply switching section module,
wherein the voltage is cut off input voltage between 140-330 VAC,
d) The Triode Alternating-Current (TRIAC) of the phase angle control module cuts off
the Voltage to the specified range of 140 volts
e) The stabilized cut off voltage is provided to the AC ballast switching module
located within the said purification module,
f) The AC Ballast switching module in turn powers the UV tube to generate UV
radiation, to purify the inlet water entering into the purification module,
g) The AC Ballast switching module, continuously powers the UV tube with
stabilized voltage to the UV tube, thereby reducing and/or attenuating any
external voltage fluctuations
h) The CPU control module monitors, the entire process of purification including the
front panel switches, visual indicators and solenoid valve
i) The purified water is stored in the Storage unit and is suitable for all purposes
including drinking.