Project Report On Ups

PROJECT OF INFORMATION ON INTERNET ON UNINTERRUPTIBLE POWER SUPPLY, ITS FEATURES AND APPLICATIONS IN VARIOUS FIELDS

1

CONTENTS PAGE NO. 1. 5

COMPANY

PROFILE 8

2. INTRODUCTION 11 3. TECHNOLOGIES(TYPES) • OFFLINE/STAND BY • LINE-INTERACTIVE • DOUBLE CONVERSION /ONLINE • Hybrid Topology • FERRO RESONANT • DC POWER • ROTARY 4. COMPONENTS OF UPS

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5. COMMON POWER PROBLEMS 20 • POWER FAILURE • VOLTAGE SPIKE • OVER-VOLTAGE • LINE NOISE • HARMONIC DISTORTION 6. HOW DOES A UPS WORKS? 27 2

7. CHARACTERISTICS 29 • ELECTRICAL CHARACTERISTICS • MECHANICAL CHARACTERISTICS

• ELECTRICAL CHARACTERISTICS (DC INTERMEDIATE CIRCUIT) • ELECTRICAL CHARACTERISTICS(INVERTOR OUTPUT) • ELECTRICAL CHARACTERISTICS(BYPASS INPUT MAINS) 8. DIFFICULTIES FACED 36 9. CIRCUIT DIAGRAM 10. 39

APPLICATIONS

WITH

GENERATOR

USE 38

AND

BUSINESS

NEED

11. UPS CONFIGURATION 41 11. 43

UPS

EFFECTIVENESS

12. 44

CONCLUSION

11. 45 z

BIBLIOGRAPHY

3

COMPANY PROFILE Emerson Network Power (India) Private Ltd., (formerly Tata Liebert Limited) is a wholly owned subsidiary of Emerson Electric, USA, a conglomerate having 22.6 Billion US$ turnover and a ranking of 115 among Fortune 500 Companies. Emerson Network Power India was set up in September 1993, inaugurated by Mr. Charles Knight,

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the legendary Chairman of the Emerson group. Since then we are witnessing growth in the country. Emerson Network Power (India) has seen CAGR of 30 %, only reaffirming our success in the Indian market. Today, we have established ourselves as market leader in the Power Protection solutions and Precision Air Condition segment. Emerson Network Power India manufactures & markets Uninterruptible Power Supply (UPS) systems, Climate and Environmental systems, DC power systems, Automatic Transfer Switches (ATS), Racks, Monitoring Solutions and Enclosures for IT Server protection and power distribution units - all supported by world-class professional services, catering to major industries such as the IT, Telecom, Banking & Finance, Process Control, Biotech, Healthcare, Retail, Infrastructure and Government sectors. India today is serving network-dependent data, telecommunications and Internet-related businesses with a full spectrum of reliable power and connectivity solutions Emerson Network Power (India) Pvt. Ltd. has provided solutions to customers all across India. An ISO 9001& ISO 14001 certified company; Emerson Network Power India crossed a major quality milestone when it was accorded Level II recognition by the MAIT (Manufacturers Association for Information Technology) in 1998. This is the highest ever recognition accorded by MAIT in India for a company and the first in the manufacturing sector. In 1999, the Confederation of Indian Industries (CII) recognized the company for its strong commitment to Quality through a Certificate under the CII-Exim Business Excellence Award.

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Emerson Network Power India is headquartered in Thane (MH). In Maharashtra the company has two plants facilities located at Thane and Nerul and is supplemented by a strong national network of offices. Emerson Network Power India today is a 1320 member strong organization and additionally addresses the requirements of various markets through over 75 business partners and 1075 resellers across India.

AWRDS AND RECOGNITIONS Emerson Network Power India is in its 13th successful year and with every year has ensured to raise the level of quality and commitment to its products and customers. The unrelenting efforts have borne fruit and the Awards & recognitions are a testimony to it. As is said, "Success is not a destination, its a journey" and in our journey, with our infallible vision and mission, we set out to achieve new echelons.

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Awards Below are some of the Awards & Recognitions: •

•

•

• •

•

• •

ISO 14001:2004 QMS & 9001:2000 QMS (Quality Management System) certification from the prestigious DNV(Det Norske Veritas), Netherlands for Design, Development, Manufacturing, Supply, Installation and Servicing of UPS, DC Power Supply System and Precision Air Conditioning Systems Acquired CMM-2 (monitoring status)

MAIT Level II Award. 1st manufacturing company to achieve this award. Highest ever award for Quality initiatives in IT sector. Using JRD Tata's quality values Referenced against the EFQM model. Highest ever recognition achieved so far by a company as a whole. Maharashtra IT award in 2005 . Received the Techies Award 3 years in a row by Computer world for Best Seller in Power conditioning equipments. The Emerson Network Power India team ranked 1st and 3rd in the IMC (Integrated Marketing Communications) competition. An international management game where marketing situations were simulated. 80 countries participated in this game Frost & Sullivan India – Voice of Customers, UPS Award’ August 2004 Product & Customer Service Leadership Award in IT / ITES / Datacenters

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• • • •

Product & Customer Service Leadership Award in Telecom products Customer Service Leadership Award in Hospitals Product & Customer Service Leadership Award in Large Enterprises Customer Service Leadership Award in Banking & Insurance

INTRODUCTION

An Uninterruptible power supply (UPS), also known as a battery back-up, provides emergency power and, depending on the topology, line regulation as well to connected equipment by supplying power from a separate source when utility power is not available. It differs from an auxiliary or emergency power system or standby generator, which does not provide instant protection from a momentary power interruption. A UPS, however, can be used to provide uninterrupted power to equipment, typically for 5–15 minutes until an auxiliary power supply can be turned on, 8

utility power restored, or equipment safely shut down. While not limited to safeguarding any particular type of equipment, a UPS is typically used to protect computers, data centers, telecommunication equipment or other electrical equipment where an unexpected power disruption could cause injuries, fatalities, serious business disruption or data loss. UPS units come in sizes ranging from units which will back up a single computer without monitor (around 200 VA) to units which will power entire data centers, buildings, or even an entire city. (several megawatts). An UPS contains an internal rechargeable battery that gets charged from the power line then gets used to generate line power to the load when the power line fails. To accomplish that they also contain an inverter, an electronic device capable of generating 110/220v AC from battery-level DC voltage. There are different types of UPS depending on how and when the power generation occurs, and how precisely sine waveshaped AC voltage they produce. Power line AC voltage is supposed to be a sine-wave, and it mostly is. UPS-generated AC is usually a lot less sine-shaped and some devices care more about than that others. For large power units, Dynamic Uninterruptible Power Supply are sometimes used. A synchronous motor/alternator is connected on the mains via a choke. Energy is stored in a flywheel. When the mains power fails, an Eddy-current regulation maintains the power on the load. DUPS are sometimes combined or integrated with a dieselgenerator, forming a diesel rotary uninterruptible power supply, or DRUPS.

9

Front side

10

Back side 11

TECHNOLOGIES(TYPES)

The general categories of modern UPS systems are on-line, line-interactive, and standby. An on-line UPS uses a "double conversion" method of accepting AC input, rectifying to DC for passing through the battery (or battery strings), then inverting back to 120v AC for powering the protected equipment. A line-interactive UPS maintains the inverter in line and redirects the battery's DC current path from the normal charging mode to supplying current when power is lost. In a standby ("off-line") system the load is powered directly by the input power and the backup power circuitry is only invoked when the utility power fails. Most UPS below 1 kVA are of the line-interactive or standby variety which are usually less expensive. For large power units, Dynamic Uninterruptible Power Supply are sometimes used. A synchronous motor/alternator is connected on the mains via a choke. Energy is stored in a flywheel. When the mains power fails, an Eddy-current regulation maintains the power on the load. DUPS are sometimes combined or integrated with a diesel-generator, forming a diesel rotary uninterruptible power supply, or DRUPS. A Fuel cell UPS has been developed in recent years using hydrogen and a fuel cell as a power source, potentially providing long run times in a small space. They are explained one by one as follows:-

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1. Offline / standby The Offline / Standby UPS (SPS) offers only the most basic features, providing surge protection and battery backup. Usually the Standby UPS offers no battery capacity monitoring or self-test capability, making it the least reliable type of UPS since it could fail at any moment without warning. These are also the least expensive, selling for as little as US$40. The SPS may be worse than using nothing at all, because it gives the user a false sense of security of being assured protection that may not work when needed the most. With this type of UPS, a user's equipment is normally connected directly to incoming utility power with the same voltage transient clamping devices used in a

common surge protected plug strip connected across the power line. When the incoming utility voltage falls below a predetermined level the SPS turns on its internal DC-AC inverter circuitry, which is powered from an internal storage battery. The SPS then mechanically switches the connected equipment on to its DC-AC inverter output. The switchover time is stated by most manufacturers as being less than 4 milliseconds, but typically can be as long as 25 milliseconds depending on the amount of time it takes the Standby UPS to detect the lost utility voltage. Generally speaking, dependent on the size of UPS connected load and the sensitivity of the connected equipment to votage variation, the UPS will be designed and/or offered (specification wise) to cover certain ranges of equipment, i.e. Personal Computer, without any obvious dip or brownout to that device.

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Offline / standby UPS. Typical protection time: 0 - 20 minutes. Capacity expansion: Usually not available

2. Line-interactive

The Line-Interactive UPS is similar in operation to a Standby UPS, but with the addition of a multi-tap variable-voltage autotransformer. This is a special type of electrical transformer that can add or subtract powered coils of wire, thereby increasing or decreasing the magnetic field and the output voltage of the transformer. This type of UPS is able to tolerate continuous under-voltage brownouts and overvoltage surges without consuming the limited reserve

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battery power. It instead compensates by auto-selecting different power taps on the autotransformer. Autotransformers can be engineered to cover a wide range of varying input voltages, but this also increases the number of taps and the size, weight, complexity, and expense of the UPS. It is common for the autotransformer to only cover a range from about 90v to 140v for 120v power, and then switch to battery if the voltage goes much higher or lower than that range.

Line-Interactive UPS. Typical protection time: 5 - 30 minutes. Capacity expansion: Several hours

In low-voltage conditions the UPS will use more current than normal so it may need a higher current circuit than a normal device. For example to power a 1000 watt device at 120 volts, the UPS will draw 8.32 amps. If a brownout occurs and 15

the voltage drops to 100 volts, the UPS will draw 10 amps to compensate. This also works in reverse, so that in an overvoltage condition, the UPS will need fewer amps of current.

Wep UPS series

3. Double-conversion / online The Online UPS is ideal for environments where electrical isolation is necessary or for equipment that is very sensitive to power fluctuations. Although once previously reserved for very large installations of 10kW or more, advances in technology have permitted it to now be available as a common consumer device, supplying 500 watts or

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less. The Online UPS is generally more expensive but may be necessary when the power environment is "noisy" such as in industrial settings, for larger equipment loads like data centers, or when operation from an extended-run backup generator is necessary. The basic technology of the online UPS is the same as in a Standby or Line-Interactive UPS. However it typically costs much more, due to it having a much greater current AC-to-DC battery-charger/rectifier, and with the rectifier and inverter designed to run continuously with improved cooling systems. It is called a DoubleConversion UPS due to the rectifier directly driving the inverter. Typical protection time: 5 – 30 minutes Capacity expansion: Several hours

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SPCUPS 48V /5A /5Ahs

In an Online UPS, the batteries are always connected to the inverter, so that no power transfer switches are necessary. When power loss occurs, the rectifier simply drops out of the circuit and the batteries keep the power steady and unchanged. When power is restored, the rectifier resumes carrying most of the load and begins charging the batteries, though the charging current may be limited to prevent the high-power rectifier from overheating the batteries and boiling off the electrolyte. The main advantage to the on-line UPS is its ability to provide an electrical firewall between the incoming utility power and sensitive electronic equipment. While the Standby and Line-Interactive UPS merely filter the input utility power, the Double-Conversion UPS provides a layer of insulation from power quality problems. It allows

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control of output voltage and frequency regardless of input voltage and frequency.

4. Hybrid Topology / Double Conversion on Demand Recently there have been hybrid topology UPSs hitting the marketplace. These hybrid designs do not have an official designation, although one name used by HP and Eaton is Double Conversion on Demand.[2] This style of UPS is targeted towards high efficiency applications while still maintaining the features and protection level offered by double conversion. A hybrid (double conversion on demand) UPS operates as an offline/standby UPS when power conditions are within a certain preset window. This allows the UPS to achieve very high efficiency ratings. When the power conditions fluctuate outside of the predefined windows, the UPS switches to online/double conversion operation.[3] In double conversion mode the UPS can adjust for voltage variations without having to use battery power, can filter out line noise and control frequency. Examples of this hybrid/double conversion on demand UPS design are the HP R8000, HP R12000, HP RP12000/3 and the Eaton BladeUPS.

5.

Ferro-resonant

Typical protection time: 5 - 15 Minutes 19

Capacity expansion: Several Hours Ferro-resonant units operate in the same way as a standby UPS unit with the exception that a ferro-resonant transformer is used to filter the output. This transformer is designed to hold energy long enough to cover the time between switching from line power to battery power and effectively eliminates the transfer time. Many ferro-resonant UPSs are 90-93% efficient and offer excellent isolation. This used to be the dominant type of UPS and is limited to around the 15KVA range. These units are still mainly used in some industrial settings due to the robust nature of the UPS. Many ferro-resonant UPSs utilizing controlled ferro technology may not interact with powerfactor-correcting equipment.

6. DC power Typical protection time: Several hours Capacity expansion: Yes A UPS designed for powering DC equipment is very similar to an online UPS, except that it does not need an output inverter, and often the powered device does not need a power supply. Rather than converting AC to DC to charge batteries, then DC to AC to power the external device, and then back to DC inside the powered device, some equipment accepts DC power directly and allows one or more conversion steps to be eliminated. This equipment is more commonly known as a rectifier.

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Many systems used in telecommunications use 48 volt DC power, because it is not considered a high-voltage by most electrical codes and is exempt from many safety regulations, such as being installed in conduit and junction boxes. DC has typically been the dominant power source for telecommunications, and AC has typically been the dominant source for computers and servers. There has been much experimentation with 48v DC power for computer servers, in the hope of reducing the likelihood of failure and the cost of equipment. However, to supply the same amount of power, the current must be greater than an equivalent 120v or 240v circuit, and greater current requires larger conductors and/or more energy to be lost as heat. High voltage DC (380 volts) is finding use in some data center applications, and allows for small power conductors, but is subject to the more complex electrical code rules for safe containment of high voltages.

7. Rotary Typical protection time: 20 – 60 seconds Capacity expansion: Several seconds

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A Rotary UPS uses the inertia of a high-mass spinning flywheel to provide short-term ride-through in the event of power loss. The flywheel also acts as a buffer against power spikes and sags, since such short-term power events are not able to appreciably affect the rotational speed of the highmass flywheel. It is also one of the oldest designs, predating vacuum tubes and integrated circuits. It can be considered to be online since it spins continuously under normal conditions. However, unlike a battery-based UPS, flywheel based UPS systems typically provide

10 to 20 seconds of protection before the flywheel has slowed and power output stops. It is traditionally used in conjunction with standby diesel generators, providing backup power only for the brief period of time the engine needs to start running and stabilize its output. The Rotary UPS is generally reserved for applications needing more than 10,000 watts of protection, to justify the expense of an extremely large and heavy power system that can only be transported by forklift or crane. A larger flywheel or multiple flywheels operating in parallel will increase the reserve running time or capacity. Because the flywheels are a mechanical power source, it is not necessary to use an electric motor or generator as an intermediary between it and a diesel engine designed to provide emergency power. By using a transmission gearbox, the rotational inertia of the flywheel can be used to directly start up a diesel engine, and once running, the diesel engine can be used to directly spin 22

the flywheel. Multiple flywheels can likewise be connected in parallel through mechanical countershafts, without the need for separate motors and generators for each flywheel. They are normally designed to provide very high current output compared to a purely electronic UPS, and are better able to provide inrush current for inductive loads such as motor startup or compressor loads, as well as medical MRI and cath lab equipment. It is also able to tolerate short-circuit conditions up 17 times larger than an electronic UPS, permitting one device to blow a fuse and fail while other devices still continue to be powered from the Rotary UPS. Its life cycle is usually far greater than a purely electronic UPS, up to 30 years or more. But they do require periodic downtime for mechanical maintenance, such as ball bearing replacement. Batterybased designs do not require downtime if the batteries can be hot-swapped, which is usually the case for larger units. Newer Rotary units use technologies such as Magnetic bearings and air-evacuated enclosures to increase standby efficiency and reduce maintenance to very low levels.

COMPONENTS

OF

UPS

Mainly UPS consists of • RECTIFIER • BATTERY CHARGER • BATTERY TANK 23

• A INVERTER CIRCUIT

Common power problems There are various common power problems that UPS units are used to correct: 1. 2. 3. 4. 5.

Power failure Voltage spike Over-voltage Line noise Harmonic distortion

UPS units are divided into categories based on which of the above problems they address, and some manufacturers categorize their products in accordance with the number of power related problems they address. They are explained as follows:-

1. Power failure:Tree limbs create a short circuit in electrical lines during a storm. This will typically result in a power outage to the area supplied by these lines. A power outage (also known as a power cut, power failure, power loss, or blackout) refers to the short- or long-term loss of the electric power to an area.

There are many causes of power failures in an electricity network. Examples of these causes include, faults at power stations, damage to power lines, 24

substations or other parts of the distribution system, a short circuit, or the overloading of electricity mains.

Power outages are categorized into three different phenomena, relating to the duration and effect of the outage: •

•

•

A dropout is a momentary (milliseconds to seconds) loss of power typically caused by a temporary fault on a power line. Power is quickly (and sometimes automatically) restored once the fault is cleared. A brownout is a drop in voltage in an electrical power supply, so named because it typically causes lights to dim. Systems supplied with three-phase electric power also suffer brownouts if one or more phases are absent, at reduced voltage, or incorrectly phased. Such malfunctions are particularly damaging to electric motors. A blackout refers to the total loss of power to an area and is the most severe form of power outage that can occur. Blackouts which result from or result in power stations tripping are particularly difficult to recover from quickly.

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•

Outages may last from a few hours to a few weeks depending on the nature of the blackout and the configuration of the electrical network.

2. Voltage spike:In electrical engineering, spikes are fast, short duration electrical transients in voltage (voltage spikes), current (current spike), or transferred energy (energy spikes) in an electrical circuit. Fast, short duration electrical transients (over voltages) in the electric potential of a circuit are typically caused by • • • • • • •

•

lightning strikes power outages tripped circuit breakers short circuits power transitions in other large equipment on the same power line malfunctions caused by the power company electromagnetic pulses (EMP) with electromagnetic energy distributed typically up to the 100 kHz and 1 MHz frequency range. Inductive spikes

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In the design of critical infrastructure and military hardware, one concern is of pulses produced by nuclear explosions , whose nuclear electromagnetic pulse (EMP) distribute large energies in frequencies from 1 kHz into the Gigahertz range through the atmosphere. The effect of a voltage spike is to produce a corresponding increase in current (current spike). However some voltage spikes may be created by current sources. Voltage would increase as necessary so that a constant current will flow. Current from a discharging inductor is one example. For sensitive electronics, excessive current can flow if this voltage spike exceeds a material's breakdown voltage, or if it causes avalanche breakdown. In semiconductor junctions, excessive electrical current may destroy or severely weaken that device. An avalanche diode, transient voltage suppression diode, transil, varistor, overvoltage crowbar, or a range of other overvoltage protective devices

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can divert (shunt) this transient current thereby minimizing voltage. While generally referred to as a voltage spike, the phenomenon in question is actually an energy spike, in that it is measured not in volts but in joules; a transient response defined by a mathematical product of voltage, current, and time. Voltage spike may be created by a rapid buildup or decay of a magnetic field, which may induce energy into the associated circuit. However voltage spikes can also have more mundane causes such as a fault in a transformer or higher-voltage (primary circuit) power wires falling onto lower-voltage (secondary circuit) power wires as a result of accident or storm damage. Voltage spikes may be longitudinal (common) mode or metallic (normal or differential) mode. Some equipment damage from surges and spikes can be prevented by use of surge protection equipment. Each type of spike requires selective use of protective equipment. For example a longitudinal mode voltage spike may not even be detected by a protector installed for normal mode transients.

3.

Over

voltage:-

When the voltage in a circuit or part of it is raised above its upper design limit, this is known as over voltage. The conditions may be hazardous. Depending on its duration, the over voltage event can be permanent or transient, the latter case also being known as a voltage spike. 28

Electronic and electrical devices are designed to operate at a certain maximum supply voltage, and considerable damage can be caused by voltage that is higher than that for which the devices are rated.

UPS-300TA For example an electric light bulb has a wire in it that at the given rated voltage will carry a current just large enough for the wire to get very hot (giving off light and heat), but not hot enough for it to melt. The amount of current in a circuit depends on the voltage supplied: if the voltage is too high, then the wire may melt and the light bulb would have "burned out". Similarly other electrical devices may stop working, or may even burst into flames if an over voltage is delivered to the circuit of which these devices are part.

4.

Signal

noise:-

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In science, and especially in physics and telecommunication, noise is fluctuations in and the addition of external factors to the stream of target information (signal) being received at a detector. In communications, it may be deliberate as for instance jamming of a radio or TV signal, but in most cases it is assumed to be merely undesired interference with intended operations. Natural and deliberate noise sources can provide both or either of random interference or patterned interference. Only the latter can be cancelled effectively in analog systems; however, digital systems are usually constructed in such a way that their quantized signals can be reconstructed perfectly, as long as the noise level remains below a defined maximum, which varies from application to application. More specifically, in physics, the term noise has the following meanings: 1. An undesired disturbance within the frequency band of

2. 3. 4. 5.

interest; the summation of unwanted or disturbing energy. A disturbance that affects a signal and that may distort the information carried by the signal. Random variations of one or more characteristics of any entity such as voltage, current, or data. A random signal of known statistical properties of amplitude, distribution, and spectral density. Loosely, any disturbance tending to interfere with the normal operation of a device or system.

Noise and what can be done about it has long been studied. Claude Shannon established information theory and in so doing clarified the essential nature of noise and the limits it places on the operation of electronic equipment. In some cases a little noise may be considered advantageous, allowing a dithered representation of signals below the minimum strength, or between two quantization levels. This is especially true for signals intended for human appreciation, since the brain seems to 30

expect signals to contain a degree of "neural noise"[1][2], or the phenomenon of stochastic resonance, where small amount of noise improves the detection of signals in nonlinear sensors

5.

Distortion

A distortion is the alteration of the original shape (or other characteristic) of an object, image, sound, waveform or other form of information or representation. Distortion is usually unwanted. In some fields, distortion is desirable, such as electric guitar (where distortion is often induced purposely with the amplifier or an electronic effect to achieve an aggressive sound where desired). The slight distortion of analog tapes and vacuum tubes is considered pleasing in certain situations. The addition of noise or other extraneous signals (hum, interference) is not considered to be distortion, though the effects of distortion are sometimes considered noise.

Correction of distortion As the system output is given by y(t) = F(x(t)), then if the inverse function F-1 can be found, and used intentionally to distort either the input or the output of the system, then the distortion will be corrected. An example of such correction is where LP/Vinyl recordings or FM audio transmissions are deliberately pre-emphasized by a linear filter, the reproducing system applies an inverse filter to make the overall system undistorted.

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Pulsar Ellipse 500 USBS UPS

Correction is not possible if the inverse does not exist, for instance if the transfer function has flat spots (the inverse would map multiple input points to a single output point). This results in a loss of information, which is uncorrectable. Such a situation can occur when an amplifier is overdriven, resulting in clipping or slew rate distortion, when for a moment the output is determined by the characteristics of the amplifier alone, and not by the input signal.

How does a computers uninterruptible power supply

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works……… What your computer expects to get from the power grid (in the United States) is 120-volt AC power oscillating at 60 Hertz (see How Power Distribution Grids Work for more information). A computer can tolerate slight differences from this specification, but a significant deviation will cause the computer's power supply to fail. A UPS generally protects a computer against four different power problems: •

Voltage surges and spikes - Times when the voltage on the line is greater than it should be.

Voltage sags - Times when the voltage on the line is less than it should be Total power failure - Times when a line goes down or a fuse blows somewhere on the grid or in the building. Frequency differences - Times when the power is oscillating at something other than 60 Hertz

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There are two common systems in use today: standby UPS and continuous UPS. A standby UPS runs the computer off of the normal utility power until it detects a problem. At that point, it very quickly (in five milliseconds or less) turns on a power inverter and runs the computer off of the UPS's battery (see How Batteries Work for more information). A power inverter simply turns the DC power delivered by the battery into 120-volt, 60-Hertz AC power. In a continuous UPS, the computer is always running off of battery power and the battery is continuously being recharged. You could fairly easily build a continuous UPS yourself with a largish battery charger, a battery and a power inverter. The battery charger continuously produces DC power, which the inverter continuously turns back into 120-volt AC power. If the power fails, the battery provides power to the inverter. There is no switch-over time in a continuous UPS. This setup provides a very stable source of power. Standby UPS systems are far more common for home or small-business use because they tend to cost about half as much as a continuous system. Continuous systems provide extremely clean, stable power, so they tend to be used in server rooms and mission critical applications.

CHARACTERISTICS:

What do entrepreneurs and investors expect of you and what should you expect of them? The criteria many large pharmaceutical and medical device companies apply to 34

potential development projects generally cover the following areas: •

Scientific Confidence. This criterion must be established over time and the levels of technical risk that are suitable for an entrepreneurial venture are likely to be too risky for a large company to undertake. Over time, the proposed mechanism of action must be supported in laboratory experiments.

•

Unmet Medical Need. If a product would only marginally improve treatment for a disease or if sufficient treatment already exists, then it is difficult to justify investing further time and money.

•

Large Market Opportunity. This area is largely selfexplanatory and is covered more in depth below.

•

Adequate Market Protection. It is critical that there is broad intellectual property protection, so that the company can be assured of recovering the large R&D costs of developing a product.

•

Manufacturing Economics. The economics of manufacturing a product cannot be so costly that it would make the eventual cost of the medicine too high.

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Electrical

Characteristics

RECTIFIER I/P Ratings Rated power Rated Mains Voltage  Supply Input voltage tolerance  Frequency Input frequency tol. Rated input power  Rated input current  Maximum input power  Maximum input current  Duration of progressive power walk-in 

INPUT

Units kVA Vac

MAINS

30 Kva 6 pulse 30 380 – 400 – 415 V Three phase without neutral

%

±10

Hz

50 or 60

% kVA A

±5 33 48

kVA

41

A

59

sec 2 to 10

 = 380V or 415V set changing taps on auxiliary supply transformer

36

 = With mains at –15% and suggested battery elements the UPS maintains the output rated voltage at rated load but cannot guarantee float charge to battery; the battery does not discharge.  = EN 50091-3 (1.4.39): UPS, rated load, input rated voltage 400V, no current to battery  = EN 50091-3 (1.4.40): UPS, rated load or overload, input rated voltage 400V, battery on boost charge with maximum allowed current.  = Set with jumper on Rectifier control board.

Mechanical

Mechani cal Characte ristics Height Width Depth Ventilatio n Cable entry Protection

characteristics

U nits

30 kVA 6 pulse

mm mm mm -

1615 830 775 By internal intake fans

-

Bottom

IP

41

37

UPS Electrical Characteristics (DC Intermediate Circuit) D. C.

INTERMEDIATE

Rated Power Voltage range for Inverter operation Recommended number of - Lead-acid cells - Ni-Cd cells - Recommended float charge voltage 2.25 V/cell (Lead Acid) 

kV A Vd c No s.

CIRCUIT 30 320 – 470

190 (380 Vac) 198 (400 Vac) 204 (415 Vac) 291 (413 Vac)

-

1.42 V/cell (Ni-Cd)  Recommended boost charge voltage 2.40 V/cell (Lead Acid) 

Vd c

432 (380 Vac) 446 (400 Vac) 459 (415 Vac) 413 Vac

Vd c

460 (380 Vac) 475 (400 Vac) 490 (415 Vac) 451 Vac

1.55 V/cell (Ni-Cd) 

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Recommended end of discharge voltage 1.67 V/cell (Lead Acid)  1.1 V/cell (Ni-Cd)  Recommended test voltage Lead Acid 

Vd c

320 (380 Vac) 330 (400 Vac) 340 (415 Vac) 320 Vac

Vd c

365 (380 Vac) 376 (400 Vac) 388 (415 Vac) 350 Vac

Ni-Cd  Battery boost charge cycle 

-

Maximum boost charge duration 

mi n

Boost-float threshold current 

A

Ripple voltage superimposed 

%

Characteristics to DIN 41772IU, boost to floating charge switching, with current measuring criterion plus control of charging time. 0-999 0-99 ≤1

Note:

39

 = (According to rated voltage)  = Factory set for rated 400V, different cells number and voltage per cell may be set by software and / or trimmers on Rectifier control board.  = Set by software  = Battery disconnected, RMS percentage value referred to DC voltage.

UPS Characteristics Output)

Electrical (Inverter

INVERTER OUTPUT Rated Power kV 30 A Rated mains Vac 320 - 400 - 415 voltage  Three phase with neutral Hz Frequency  50 to 60 Rated Power at cosφ = 0.8

KV A

30

Rated Power at KW cosφ = 1 Maximum non linear load allowed  Maximum rate of Hz change of /se c frequency 

24

100% Pn 0.1

40

Note:

 = Factory set 400V – 380V or 415V voltages with software setting  = Factory set at 50Hz ; 60Hz with software setting.  = EN50091-3 (1.4.58) crest factor 3.  = EN50091-3 (4.3.4).  = EN50091-3 (4.3.7) also for 0-100% load transient, restore time 20ms to ±1%.  = Factory set at 0.1Hz/ sec; upto 2 Hz/sec with software setting.

UPS Electrical Characteristics (Bypass Input Mains) BYPASS Rated Power kV A Rated mains Va c voltage  Supply Rated Current: 230 Vac Bypass voltage tolerance 

INPUT

MAINS 30

320 - 400 - 415 Three phase with neutral

A

130

%

± 10

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Delay time to sec recognize bypass voltage returned to window Inverter output % voltage window Frequency 

Hz

Input frequency tolerance 

%

Maximum frequency slew rate

Hz /se c

± 10 50 or 60 ±2

Current rating of neutral cable

0.1

1.5 x In

Protection, bypass line

Overload

10

%

To avoid series fuses, the bypass line should be protected using an external device should be sized to discriminate with the load protection. 150% for 60 sec 125% for 10 min 110% for 1 hr

Note:  = Factory set 400V – 380V or 415V set changing taps on auxiliary supply transformer and with software setting  = Other values 0-15% with software setting.  = Factory set at 50Hz ; 60Hz with software setting.  = Other values 1-9% with software setting.

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Difficulties faced

with generator use The voltage and frequency of the power produced by a generator depends on the engine speed. The speed is controlled by a system called a governor. Some governors are mechanical, some are electronic. The job of the governor is to keep the voltage and frequency constant, while the load on the generator changes. This may pose a problem where, for example, the startup surge of an elevator can cause short "blips" in the frequency of the generator or the output voltage, thus effecting all other devices powered by the generator. Many transmission sites will have backup diesel generators - in the case of AM, the load presented by the transmitters changes in line with the signal level. This leads to the scenario where the generator is constantly trying to correct the output voltage and frequency as the load changes.

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It is possible for a UPS unit to be incompatible with a generator or a poor mains supply; in the event that its designers had written the microprocessor code to require exactly a 50.0Hz (or 60.0Hz) supply frequency in order to operate; with this condition not met the UPS could remain on battery power, being unable to reconnect the unsuitable supply voltage. This problem of input frequency requirements should not be an issue through the use of a Double Conversion / online UPS. A UPS of this topology should be able to adapt to any input frequency, using its own internal clock source to generate the required 50 or 60Hz supply frequency. A problem in the combination of a "double conversion" UPS and a generator is the voltage distortion created by the UPS. The input of a double conversion UPS is essentially a big rectifier. The current drawn by the UPS is non-sinusoidal. This causes the voltage from the generator also to become nonsinusoidal. The voltage distortion then can cause problems in all electrical equipment connected to the generator, including the UPS itself! This level of "noise" is measured as a percentage of "Total Harmonic Distortion of the current" (THD(i)). Classic UPS rectifiers have a THD(i) level of around 25-30%. To prevent voltage distortion, this requires generators more than twice as big as the UPS.

There are several solutions to reduce the THD(i) in a double conversion UPS: Classic solutions such as passive filters reduce THD(i) to 5-10% at full load. They are reliable, but big and only work at full load, and present their own problems when used in tandem with generators. An alternative 44

solution is an active filter. Through the use of such a device, THD(i) can drop to 5% over the full power range. The newest technology in double conversion UPS units is a rectifier that doesn't use classic rectifier components (Thyristors and Diodes) but high frequency components (IGBTs). A double conversion UPS with an IGBT rectifier can have a THD(i) as small as 2%. This completely eliminates the need to oversize the generator (and transformers), without additional filters, investment cost, losses, or space.

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CIRCUIT

DIAGRAM:

46

APPLICATIONS

AND

BUSINESS NEED

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 On-Line Double Conversion technology with IGBT based PWM Inverter – A Full-Proof Solution to protect customers valuable & sophisticated load – Critical loads are not exposed to vulnerable mains power aberrations (e.g mains power surges, sags, frequency errors etc) .  Wide Input Voltage Tolerance (+10% to –15%) – Virtually address all power profiles and protect the load – Saves battery usage and thereby increasing actual autonomy time  Wide input frequency (+/- 5%) – Ensure availability of load under poor supply conditions, thus ensuring continuous running of business. – Even beyond the stipulated range of frequency the loads remain protected with constant frequency.  Electronic cards are located away from Heat generating component. – Ensures Highest degree of reliability and thus protects customer’s business  Microprocessor controlled design – Lowest component count which leads to greater degree of reliability  Intelligent Battery Management – Ensures Proactive measures to check battery health thus avoiding surprises which may lead to disaster. – UPS automatically test battery healthiness on programmed schedule – No risk involved that will lead to failure of business – Temperature compensated battery charging – VRLA battery life is prolonged even under high ambient temperature. – Saves initial investment – Ensures reliability of the solution under adverse environment conditions.

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 Common Battery Sharing Kit (Optional) with 1+1 configuration – Achieve true parallel redundancy which leads to high availability of power to critical load • Ensure Criss-Cross operation • One Rectifier of a module can feed the load via the inverter of another module! – Ensure much better battery charging and thus keeping battery fully charged even under failure of input feeder to one UPS module. • In case of failure of input power of one UPS the charging current of other rectifier gets automatically adjusted to ensure proper charging  Multiple configuration of UPS helps Right Solution For Right Applications with Hyper Degree of Criticality Index – Single Module – 1+1 Parallel redundant configuration – Hot-stand by Configuration – Eco-Mode Operation – Dual Bus Redundancy for Highest Degree of Availability of power and HIGH NINE uptime Solution  Load handling Capability – High Crest Factor Load ( 3:1) – 100% Non-Linear Loads – 100% unbalanced Load

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UPS Configurations: 1. SM, 1+1

BYPASS SUPPLY

INPUT SUPPLY 415V AC 3PH, 4WIRES

BYPAS S STATIC INVERT ER

RECTIFI ER

INVERT ER STATIC SWITC

UPS BATTER Y OUTPUT TO LOAD

2.LBS (A)

50

(B) B S E S

T

MAIN DB Changeover

Mains Transformers

UPS 1

UPS 2

PD

MAIN DB Changeover

DG Sets

Load Bus Synchronised UPS 3

UPS 4

UPS 5

UPS 1

UPS 2

UPS 3

UPS 4

UPS 5

PD

Set of PDU Sync. Output

Set of PDU

Static Switches

Racks

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UPS

EFFECTIVENESS

Power Quality Problem

OFF LINE

LINEINTER.

1. 2. 3. 4. 5.

90% 50% 50% 80% 90%

95% 60% 90% 95% 95%

Main Outages Over Voltage / Surges Under Voltages / Sags Spikes Noise / RFI

ON LINE Double Conversion 100% 100% 100% 100% 100% 52

6. Wave form Distortion 0% 7. Frequency Variation 0% 8. Overall55% effectiveness

0% 0% 85%

100% 100% 100%

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