|Title of Invention||
"POWER INTERFACE UNIT"
|Abstract||The invention relates to a compact power interface unit, which is fully integrated telecom power rack. The present invention particularly related to an compact power interface unit comprising of a control module responsible for management of peripheral units, a power conditioner unit, AC power distribution unit, and Auto Mains Failure (AMF) system. The control module measures the battery back-up and temperature back-up to delay the start of generator during power failure.|
|Full Text||Field of the invention
The invention relates to a compact power interface unit for telecom application. It is also known as integrated electrical panel, which is fully integrated telecom power rack.
Back ground of the invention
The power interface unit is the most innovative solution for power conditioning and control of site equipments. Till very recently, various equipments like servo stabilizer, isolation transformer, auto mains failure (AMF) panel, AC distribution board (ACDB), alarm panel, lightening arrester etc were being used as independent units for the above purpose.
The previously known units occupy excessive space and need separate cabling to connect the units.
The previously known units use generator to support operating equipment during power failure. It includes numerous electro mechanical components which require frequent maintenance like carbon brush replacement of servo staLilizer. Since these units efficiency was low, they were dissipating lot of heat and further air-conditioning was needed to remove the heat. Because of heat dissipation and its removal, it was consuming more power.
In addition to that, the technology was based on electro-mechanical components so they were slow to respond input power fluctuation leading to frequent operating equipment damage. Because of the same reason, during extreme low voltage they were not able to take care of starting current of air conditioners needed at site hence leading to continuous usage of generator power. More over, the electro-mechanical components were plagued with low voltage chattering problems.
In addition, the relay based auto mains failure (AMF) panel is bulky and many relay require frequent replacement and slow to respond.
The previous known PIU had a problem of reverse recovery time (Trr) deficiency and getting frequent failure and hence site outage. It was not able to operate inductive and capacitive load. The PIU also had a problem that it hrd no
communication ports to access the information and transmit the data. The earlier PIU was not able to meet regulation requirement.
Detailed description of the invention
Accordingly, the present invention provides power interface unit comprising of a control module responsible for management of peripheral units, a power conditioner unit, AC power distribution unit, and Auto Mains Failure (AMF) system.
The peripheral units are selected from battery charger, auto phase selector, fire and intruder alarms and voltage protection module.
In an embodiment the control module controls the peripheral units as well as the auto mains failure (AMF).
In another embodiment the control module measures the battery back-up and temperature back-up to delay the start of generator during power failure.
Another embodiment is to provide a control module is adapted to transmit data from the site to centralized location(s).
In another embodiment of the invention, the power conditioner u.iit is combination of power regulator and isolation transformer.
Still another embodiment is to provide a auto mains failure (AMF) panel which is integrated with battery charger and data transmission unit.
In another embodiment, the control modules are based on True RMS measurement, which controls all peripheral including auto mains failure (AMF). The control modules measure the battery back up and temperature back-up to delay the start of generator during power failure called PCM DG Management circuitry. The control modules are adapted to transmit data wirelessly from the
site to centralized location(s) to manage remotely many sites for its operation and maintenance. The data inter-alia contains all the voltages, power consumptions, alarm logs, generator data, faults, its history and other relevant site information.
The power conditioner unit of the present invention, is a combination of power regulator and Isolation transformer controlled by the control module(s) by using True RMS measurement, differential amplifier sensing and reverse recovery time protection system. The unit offers efficiency greater than 95% and much faster response time to avoid the problem of conventional units.
The auto mains failure (AMF) panel alternates the source from ma>ns to generator vice-versa, based on the controller module input and temperature, battery back-up status of the site. The auto mains failure (AM!7) panel is integrated with battery charger and interface unit, which provides SMPS based DG battery charging and transfer of the data of the generator from control module. The SMPS based battery charger offers smooth charging of generator battery to enhance DG battery life and charging status.
In another embodiment of the invention, the compact power interface unit is further provided with lightening protection unit in combination with surge protection.
The PIU of the present invention is having integrated in 19" telecom rack in 600/400 and 600/600 foot print. The PIU accommodates the following units in all possible combination and termination:
The unit is based on high-speed micro-controller like 89 series of ATMEL or RD2 of Philips. Analogue and digital signals are interfaced through appropriate interface ICs to the micro controller. All the measurements are measured as true RMS values. The measurements are accurate (high resolution) and most reliable which leads to a very smooth intended function of the unit. This unit is central processing unit of PIU for all its activities connected with Modem to send data everyday as a routine or at particular time requested or generated during alarms. It has also RS-232 communication port, and local man machine interface in the
form of LCD panels and LED alarms to interact with equipment for its various operations. The input power is monitored and measured, if beyond limits (high/low voltage) and site condition are out of threshold limit for temperature and battery back-up then the same unit provides DG start-up and running command according to need. This provides major saving in DG running time.
Power Conditioner unit
Power conditioner unit may be based on a static tap selector technology. This unit employs static switch like thyristor, IGBT etc with differential amplifier based device (switch) switching-off sensing, software based true RMS voltage measurement technique and routine software delay for compensating reverse recovery time of device to avoid simultaneous switching-on of many device. Because of these techniques, the output is corrected very fast and there is no gap in output waveform during correction. Moreover, the above technique ensures power conditioners smooth operation in steep change in input power and poor power factor load. The tap selector unit made possible to design a line conditioner to regulate mains input voltage for all kind of load without interruption in output waveform. The power conditioner comprises of isolation transformer, micro-controller based module, and switches device along with switchgear and filters.
The voltage is measured through true RMS software and particular switch (tap) is selected as per the output voltage range and threshold. Once input changes, the controller switches-off the running device and waits for differential amplifier confirmation for the same. Then controller waits for reverse recovery time (Trr) of the switch and then it activates the desired switch in ON condition. This process of selection enables fast decision-making and tap selection of static switch to ensure uninterrupted output.
The special property of differential amplifier technology is used to offer protection for inductive and capacitive load for sensing the zero current through device. This semi-conductor (switch) controlled regulator, can operate for any inductive and capacitive load. The combination of true RMS voltage measurement through software, sensing device switch off through differential amplifier connected
across the devices thereby offering very high device reliability during steep voltage variation with inductive, capacitive and resistive load without interrupting output wave form. The design also ensures power regulation with greater efficiency.
This unit facilitates to replace servo stabilizer as well as isolation transformer with features of better regulation, fast correction speed and better efficiency. This unit is designed for single phase as well as phase-to-phase operation. However, in 3-phase operation, it also works on phase to phase, to get rid of neutral floating problem. At the same time, it also provides better mains utilization even at extreme low voltage, w.r.t. Neutral, which leads to less dependency on DG set.
This unit is used to utilize the power regulation efficiently with fast correction even under extreme low voltage conditions which servo technology is not able to offer due to its slow response.
The system do not introduce any harmonic distortion to the sine wave and very silent in operation. This unit is based on advance computing system, which performs all true RMS measurement of voltages with high and low disconnect facility. This type of measurement ensures correct analysis at right time for trouble free operation.
The technical details of the power conditioner unit are as follows: Specification
Static Line Conditioner, High-speed micro controller based true RMS measurement of current and voltages. Power Rating is 1KVA-500KVA.
Input voltage range: Single Phase-130V to 285V and Phase to Phase-240V to 485V
Output voltage range: 220 + 10% and Input frequency range: 47 - 52 Hz.
Output power factor: + 0.3
Efficiency > 95% at full load and 415V input voltage.
Correction time: 10 milli-seconds
THD: As input, no output interruption
AC Power distribution unit
AC Distribution panel is provided for load termination. There is group of MCBs connected with the surge arrester as final termination point.
Auto Mains Failure (AMF) System
AMF system connects mains or generator as per the logic. This unit provides all protection and alarm needed for telecom site. This unit also disconnects the power during fire, smoke and switches-off the DG in case of any DG failure alarm or in case of extreme high and low voltage (voltage protection module). The CPU, PCM-DG management circuitry senses telecom battery voltage and shelter temperature and switches-on the generator whenever limit threshold arrived. The limit threshold can be adjusted as per requirement. It is also inbuilt with mechanical Interlock to avoid any electrical short circuit during microcontroller failure or malfunctioning of systems. AMF system is integrated with the DG battery charger and interface unit to communicate, control, and operate diesel generator.
PIU input: The input panel provides the user terminals for mains, DG and power earthing termination point. It also accommodates lightning arrester as an entry barrier to the equipment.
Input MCBs: MCBs (miniature circuit breaker) are used for protection of electrical circuits to operate on wide input range of mains/DG. Its rating depends upon the rating of PIU.
Phase Selection: The phase selector have been integrated in PIU to select any two good phase or one good phase as per LCU operating range needed as per site PIU capacity.
Lightning arrester: This is Class B protection with high follow-on current limitation is used for protection against lightening as per IEC-61312 rated for 10/350us multi strike.
SMPS Rectifier: SMPS rectifier for telecom battery charging also can be integrated in the same panel.
DG battery charger and control interface unit: The power interface unit has been designed considering the requirements of an automated telecom site. Hence, control interfacing is required. The DG set controls is interfaced with control module. This also charges the DG battery using SMPS, battery charger to enhance the battery life.
1. A compact power interface unit comprising of a control module based on
high-speed micro-controller responsible for management of peripheral units, a power conditioner unit based on advance computing system, AC power distribution unit provided for load termination, and Auto Mains Failure (AMF) system which connects mains or generator as per the logic as herein described.
2. The compact power interface unit as claimed in claim 1, wherein the
peripheral units are selected from battery charger, auto phase selector, fire
and intruder alarms and voltage protection module.
3. The compact power interface unit as claimed in claim 1, wherein the control
module controls the peripheral units as well as the Auto Mains Failure (AMF).
4. The compact power interface unit as claimed in claim 1, wherein the control
module measures the battery back-up and temperature back-up to delay the
start of generator during power failure.
5. The compact power interface unit as claimed in claim 1, wherein the control
module is adapted to transmit data from the site to centralized location(s).
6. The compact power interface unit as claimed in claim 1, wherein the power
conditioner unit is in combination of power regulator and isolation transformer.
7. The compact power interface unit as claimed in claim 1, wherein the Auto
Mains Failure (AMF) panel is integrated with battery charger and data
8. The compact power interface unit as claimed in claim 1, wherein the compact
power interface unit is provided with lightening protection unit.
9. The compact power interface unit as claimed in claim 1, wherein the compact
power interface unit is provided with surge protection unit.
|Indian Patent Application Number||1782/DEL/2004|
|PG Journal Number||36/2006|
|Date of Filing||21-Sep-2004|
|Name of Patentee||M/S. ACME TELE POWER (P) LTD.|
|Applicant Address||PLOT NO. 48,SECTOR-5, IMT MANESAR-122 050, GURGAON(HARYANA), INDIA.|
|PCT International Classification Number||H02J 5/00|
|PCT International Application Number||N/A|
|PCT International Filing date|