FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
&
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION
[section 10 and ruls 13]
1. TITLE OF THE INVENTION: POWER MANAGEMENT SYSTEM
2. APPLICANT:

a) NAME: Global Towers Limited
b) NATIONALITY: India
ADDRESS: do: Blue Crane: 201, 2nd floor, Peninsula Chambers, Peninsula Corporate Park, G. K. Marg, Lower Parel (W), Mumbai; 400013
The following specification particularly describes the invention and the manher in which it is to be performed.

POWER MANAGEMENT SYSTEM
CROSS-REFERENCE TO RELATED APPLICATION
This application is a complete specification claiming benefit from
provisional application number 1161/Mum/2011 filed on April 6lh 2011. FIELD OF INVENTION
The present invention is directed to a power management system.
More particularly the present invention is directed to a power management system for use in a telecommunication industry.
BACKGROUND OF INVENTION
Numerous efforts have been directed towards minimizing energy
consumption in various industries. One such industry that is actively working towards minimizing energy consumption is the telecomm industry. Typically, as is known in the art, a telecom site comprises a tower that supports the antennae for transmission and reception, and a confined space (i.e., a shelter: for indoor sites) that houses at least one base transreceiver station (BTS) and other infra-equipment such as battery, switch mode power supply (SMPS), etc. BTS and microwave equipment or fiber optic interface are typically the main communication equipment at the site. A network can be that of any of the wireless communication technologies like GSM, CDMA, WLL, WAN, WiFi, WiMAX etc.

The BTS forms part of the base station subsystem (BSS)
developments for system management. It may also have equipment for
encrypting and decrypting communications, spectrum filtering tools (band pass
filters), etc. Typically a BTS will have several transceivers (TRXs) which allow it
to serve several different frequencies and different sectors of the cell (in the case
of sectorised base stations). A BTS is controlled by a parent base station
controller via the base station control function (BCF). The BCF is implemented
as a discrete unit or even incorporated in a TRX in compact base stations. The
BCF provides an operations and maintenance (O&M) connection to the network
management system (NMS), and manages operational states of each TRX, as
well as software handling and alarm collection. The basic structure and functions
of the BTS remains the same regardless of the wireless technologies.
During the working of the BTS heat is generated. The
temperature inside the confined space housing the BTS needs to be effectively controlled to avoid overheating of the space within the shelter and BTS. A standard feature of a confined space includes a heat controlling unit, say for example, an air-conditioning unit which is employed to maintain the temperature and humidity within the confined space. The air-conditioning unit is typically powered by alternate current or direct current electric supply from electricity board (EB).
Electricity losses in India during transmission and distribution are
extremely high and vary between about 30 percent to about 45 percent. For example, in 2004-05, electricity demand outstripped supply by about 7 percent to about 11 percent. Due to shortage of electricity, power cuts are common throughout India. Typically, backup power may be supplied by using a diesel

power generator (DG) unit or batteries, which provide power in the event of failure of EB supply. Renewable energy sources may also be employed to supplement EB supply. The Indian Government is also looking at certain transmission strategies with focus on development of national grid including interstate connections, technology upgradation and optimization of transmission cost. Additionally, the Indian government is looking at distribution strategies to achieve distribution reforms with focus on system upgradation, loss reduction, theft control, consumer service orientation, quality power supply commercialization, and decentralized distributed generation and supply for rural areas. Another strategy that is being put in place includes conservation strategy to optimize the utilization of electricity with focus on demand side management, load management, and technology upgradation to provide energy efficient equipment or gadgets.
As is known to one skilled in the art, three-phase electric power
system is a common method of alternating current electric power generation, transmission, and distribution. It is a type of polyphase system and is the most common method used by grids worldwide to transfer power. It is also used to power motors and other large loads.
In a three-phase electric power system, three circuit conductors
carry three alternating currents (of the same frequency) which reach their instantaneous peak values at different times. Taking one conductor as the reference, the other two currents are delayed in time by one-third and two-thirds of one cycle of the electric current. This delay between phases has the effect of giving constant power transfer over each cycle of the current and also makes it possible to produce a rotating magnetic field, for example, in an electric motor.

Three-phase systems may have a neutral wire. A neutral wire allows the three-phase system to use a higher voltage while still supporting lower-voltage single-phase appliances, In high-voltage distribution situations, it is common not to have a neutral wire as the loads can simply be connected between phases (phase-phase connection). Three-phase system has properties that make it very desirable in electric power systems: 1) The phase currents tend to cancel out one another, summing to zero in the case of a linear balanced load. This makes it possible to eliminate or reduce the size of the neutral conductor; all the phase conductors carry the same current and so can be of the same size, for a balanced load. 2) Power transfer into a linear balanced load is constant, which helps to reduce generator and motor vibrations. 3) Three-phase systems can produce a magnetic field that rotates in a specified direction, which simplifies the design of electric motors.
However, in certain locales, it is not only total failure of EB power
supply which is of concern. There may be time periods when the EB power supply is not properly distributed or balanced over the three-phases as described above. For example, if one phase is not providing power, and other phases provide the expected power output, to an observer, the visible output voltage is the same whether one, two, or three phases are working. Though the output voltage is the same, the input voltage to any equipment, for example an electric motor, is distorted as the three-phases are unevenly balanced. There appears to be no provision available currently in the industry to balance an unbalanced EB output voltage load over an input voltage load to any equipment. Under situations where the load is unbalanced, back-up power; say for example DG unit or batteries is typically initiated to provide a balanced load to the equipment.

Various attempts have been made to optimize the DG unit usage.
Typically, in the current set-up in a telecom industry, the DG unit may not only be switched on if the EB power supply fails but is also switched on if the output voltage of the EB power supply is not properly distributed to provide a balanced load. This may result in excessive usage of the DG unit, resulting in excessive fuel costs. Thus there is a need for an improved and cost effective power management system that may assist in minimizing the usage of the DG unit, and thus help in reducing the operating costs in the telecom industry.
SUMMARY OF INVENTION
In one embodiment, is provided a power management system.
The power management system comprises an automatic static voltage regulator unit (AVR), an automatic mains failure unit (AMF), and a phase switcher by balancing the power supply in a step-wise or digital manner. The automatic static voltage regulator unit is configured to continuously monitor an input voltage provided by a power supply (provided by the Electricity board) and regulate the power supply given to an equipment using the phase switcher by balancing the power supply in a step-wise or digital manner. The AMF is configured to continuously monitor an output voltage from the AVR and the performance of a diesel power generator. The power management system may further include an AVR bypass configured to directly connect the power supply to the AMF. The power management system may further include an advanced inverter unit (Al) which is configured to continuously monitor an input voltage provided by a direct current distribution board (DCDB) power supply through a switch mode power

supply and regulate the DCDB power supply given to an equipment by continuously balancing the input voltage.
In another embodiment, is provided a power management system.
The power management system comprises an Al, an AMF, and an SMPS. The
Al is configured to continuously monitor an input voftage provided by a DCDB
power supply through the SMPS and regulate the DCDB power supply given to
an equipment by continuously balancing the input voltage. The AMF is
configured to continuously monitor an output voltage from the Al and the
performance of a diesel power generator. The power management system may
further include an AVR and a phase switcher, wherein the AVR is configured to
continuously monitor an input voltage provided by a power supply and regulate
the power supply given to an equipment using the phase switcher by balancing
the power supply in a step-wise or digital manner. The power management
system may further include an AVR bypass configured to directly connect the
input voltage of the power supply to the AMF and an AMF bypass configured to
directly connect the diesel generator unit to a load monitor.
In yet another embodiment is provided a method for managing
power. The method comprises providing a power management system comprising an AVR; an AMF; and a phase switcher. The method further comprises using the AVR to continuously monitor an input voltage provided by a power supply and regulate the power supply given to an equipment using the phase switcher by balancing the power supply in a step-wise or digital manner, and using the AMF to continuously monitor an output voltage from the AVR and the performance of the diesel power generator.

In still yet another embodiment, a method of regulating a diesel
generator unit is provided. The method provides a power management system comprising an Al; and an AMF. The method includes using the Al to continuously monitor an input voltage provided by a DCDB power supply through a switch mode power supply and regulate the DCDB power supply given to an equipment by continuously balancing the input voltage; and using the AMF to continuously monitor an output voltage from the Al and the performance of the diesel power generator.
By employing the above discussed power management system
and method of switching on the DG unit only in the event of AVR power supply failure, considerable and sizeable energy and cost savings may be achieved.
BRIEF DESCRIPTION OF FIGURE
FIG. 1 provides a schematic representation of a power
management system in accordance with embodiments of the instant disclosure.
DETAILED DESCRIPTION
Embodiments of the invention as disclosed herein provide an
improved system for minimizing the use of a DG unit to run an equipment when compared to systems available in the prior art. Currently, telecom sites are equipped with equipments including power management units (PMU) and servo or static voltage stabilisers. These equipments play a primary role in minimizing the DG unit run time, i.e., DG unit usage, by way of maximising EB power usage.

The equipments may also be equipped with built in AMF Controllers. The function of the AMF controllers includes deciding the event (i.e., for example, a situation of EB power failure) to initiate DG unit switch ON. The AMF controllers may also be equipped with the capabilities of using EB power even where certain phases of the EB power fail to provide power supply, provided the available phases can be substantially evenly distributed for providing the power supply requirements of the telecom site and keep the site satisfactorily operational. The currently available power management units may be equipped with a certain algorithm to keep the DG unit switched Off if the battery backup at the telecom site is sufficiently charged.
The battery backup may then be used as the primary source of
power for a period of time until the battery backup is capable of providing the necessary power requirement of the telecom site. In certain embodiments, the current PMU's are also equipped with shelter temperature monitoring, especially for indoor sites where the BTS and other equipments mentioned above are placed inside a confined space. Depending on the temperature the requirement for the AC unit to be switched ON may be sensed by the PMU, and in the event of unavailability of EB supply or battery back-up the DG unit may be switched ON to run the AC unit and maintain the required temperature inside the confined space. In some other embodiments, where a telecom site incorporates renewable energy sources such as solar or wind power, the renewable energy sources can be monitored and if sufficient power is available to run the telecom site the DG can be switched OFF. But such a system may still require the DG to be switched ON, especially, at indoor installations, when the temperature inside the shelter increases and necessitates the need for AC unit to be switched ON.

As discussed above, a lot of efforts are being made to use
whatever power sources are available to keep the DG unit operation to a minimum. A primary advantage and function of the system disclosed herein is to regulate and minimize the use of the DG unit in addition to meeting all the requirements being met by the currently available PMU's. The system comprises an AVR, an AMF, and a phase switcher, which together are configured to control the performance of a diesel power generator. The AVR is configured to continuously monitor an input voltage provided by a power supply and regulate the power supply given to an equipment using the phase switcher. The AVR covers a wide input voltage supply range of about 240 volts to about 485 volts (Phase to Phase) and about 155 volts to about 280 volts (Phase to Neutral) and provides a stable output voltage of substantially or reasonably evenly distributed 220 Volts (+/- 10 percent). The AMF is configured to continuously monitor an output voltage from the AVR unit. The AMF continuously monitors the AVR output voltage and the performance of the DG unit. Depending on whether the DG unit is in an enabled state or a disabled state, the power management system automatically switches ON to the DG unit and transfers load to the DG unit whenever there is a complete failure in AVR power supply. However, if the phases are unevenly loaded, the phase switcher first attempts to select the best available phase and provide the best available phase as input voltage to the AVR. Thus the power management system 100 described herein, first attempts to distribute the available load substantially evenly over the available phases before switching ON the DG unit instead of Immediately switching on the DG unit when there is load imbalance as is currently practiced in the art. A method of

managing power by regulating the DG unit usage and minimizing the DG unit usage is also provided.
Certain embodiments of the power management system described
herein are explained in detail using FIG. 1. Referring to FIG. 1, a power management system 100 in accordance with embodiments disclosed herein is provided. The power management system 100 comprises an AVR 110 and an AMF 112. The power supply from EB i.e., the mains supply 118 is initially passed through a phase monitor 120. The output voltage 122 from the phase monitor is in one embodiment fed to the AVR 110 after being passed through a phase switcher 116. The output voltage from the AVR 110 is then fed to the AMF 112 through an AVR bypass 126. The phase switcher 116 functions as a best phase selector and selects the best phase available from the EB power supply 118 to be fed into to the AVR 110. In another embodiment, the output voltage 122 of the phase monitor 120 may be directly fed to the AMF 112 through the AVR bypass 126 without passing through the phase switcher 116 or the AVR 110. In certain embodiments, the output voltage 122 may be directly fed 123 to the AMF 112 without passing through either AVR 110 or the AVR bypass 126. The AMF 112 monitors the output voltage from the AVR 110. The output voltage 128 from a diesel power generator 114 and the output voltage 132 from a backup power source 130 (for example a temporary backup source like battery power or renewable energy sources) are also monitored by the AMF 112. The DG output voltage 128 may be directly connected to the AMF 112 or to the AMF bypass 134. Based on the output voltage 124 provided by the AVR 110 using the phase selector 116, the AMF 112 provides a signal to a main controller 136 and communicates the need to switch ON or switch OFF the DG unit 114. The main

controller 136 accordingly provides a command for switching ON or switching OFF of the DG unit 114. The AMF 112 provides two output voltages a regulated output voltage 138 and an unregulated output voltage 140. The regulated output voltage 138 and the unregulated output voltage 140 are connected to load monitors 142 and 144 respectively. The load monitors 142 and 144 provide unregulated alternating output voltage 146, 148 to alternating current distribution boards 150 and 152 respectively. The unregulated alternating current output voltage 1154 is then fed to a SMPS phase switcher 156. The phase switcher 156 selects the best phase available and provides the output voltage 158 in an internal or external manner 160 to SMPS 162, in a manner which ensures the equal sharing of the load on all available phases. The output voltage 164 of SMPS 162 is then fed to the DCDB 166. The output voltage 168 from the DCDB 166 is then fed to equipments that required direct current loads. A part of the output voltage 170 from the DCDB 166 may be fed to the AVR bypass 126 via the AVR output voltage 124 through the Al 172 to provide a continuously balanced output voltage 174 by continuously balancing the input voltage 170 to the AMF 112.
In one embodiment, the power management system 100 provides
a step wise or digital balartdng using the phase switcher 116 and the AVR 110 and hence provides a balanced input voltage (i.e., a balanced load or balanced power supply) to the AMF 112. The AMF 112 monitors the balanced input voltage 124 and accordingly sends in a signal to the main controller 136. Since the load is balanced by substantially evenly balancing the input voltage load, the required load for the equipments is available from the AVR 110 and the main controller 136 instructs to DG unit 114 to stay in switched OFF condition.

Alternatively or additionally, the SMPS 162 may provide a DC load 164 to the
DCDB 166. One portion of the output voltage 170 is passed through an Al 172
which provides a continuous balancing of the output voltage load 170 and
provides continuously balanced load 174 to the AMF 112 though the AVR bypass
126. Thus by employing the step-wise or digital balancing provided by AVR 110
or the continuous balancing provided by Al 172 the switching ON of the DG unit
114 may be delayed till the vent of total AVR failure occurs. The AMF 112, the
phase monitor 120, the phase switcher 116, the SMPS phase switcher 156, and
the load monitors 142 and 144 are controlled by the main controller 136. The
AVR 110 and the Al 172 give their feedback to the main controller 136 which in
turn provides the signals to the units controlled by the main controller 136. As
used herein the term "load" refers to voltage of the input power supply or the
output power supply to and from any source or equipment.
As used herein, "Auto Mains Fail" (AMF) 112 is an efficient robust
system; which can manage the power requirements at an un-manned base
station and provide a single point control and monitoring facility for superior and
efficient operational performance over conventional AMF and Servo Systems.
The AMF 112 continuously monitors the AVR 110 output voltage 124 and
performance of the diesel generator unit 114. With the AVR 110 output voltage
124 failure, and depending on the status of the DG unit in an enabled or disabled
status the power management system 100 automatically switches ON the diesel
generator unit 114 and transfers load to DG unit 114 when required.
Additionally, an AMF unit 112 is built with surge arrestors (not
shown in figure). The Surge arrestors provide the protection for load against lightening and surges come on the output voltage supply. The AMF unit 112 may

also monitor the auxiliary functions-door open, fire/smoke etc.. The AMF unit 112 extends the DG unit 114 status and power supply status alarms to the BTS with potential free contacts. AMF may have the following units that enable the AMF to perform its operations as discussed above.
As used herein, a Master Control Unit (MCU) 136 monitors and
controls the complete operation of an AMF 112 and an AVR 110 regulates the mains supply i.e., power supply from the electricity board and provides isolated supply to load. "Master Control Unit" (MCU) primarily functions to monitor, display and control the AMF operation. MCU monitors output voltage supply of AVR (220 Volts +/-10 percent), DG unit supply and also control load connection with mains supply and DG unit. As long as the output voltage supply of AVR is within the pre-defined voltage range, the MCU connects the load to AVR output voltage. When AVR output voltage supply is OFF or out of the pre-defined voltage range then, MCU will switch ON the DG unit, depending on the status at DG unit, i.e., if DG unit is enabled or disabled. The AMF will provide signal to switch ON the DG unit, even if the voltage provided by the DC battery bank is lower that required or if the temperature raises to emergency temperature, say for example above 40 degrees Celsius and report the same to MCU. Accordingly, the MCU will switch the load to DG unit output voltage. Serial port interface is provisioned with MCU to communicate with MODBUS protocol. A keypad, LCD display interfaces are provided to the MCU so that the user can view the display data like voltage, currents, battery voltage, and temperature interactively. The MCU also measures and displays output voltage power in kilowatts and kilowatt-hours. Thus if the evenly balancing of input voltage to the AMF provided by AVR or by the Al is efficient, the input voltages are effectively

balanced and the signal to switch on the DG unit from the AMF is delayed, even
if the input voltage of the power supply from the electricity board or the input
voltage of the DC supply from the SMPS is not uniform, (not shown in figure)
DG Control Unit functions to switch ON or switch OFF the
generator and give the DG unit status to the MCU. The DG control unit includes a DG charger card, a DG control card, and a DG relay card which is located at DG unit. DG control card (DCC) has a stand-alone high-speed micro controller unit designed to monitor the status and control the DG unit. Main function of DCU is to regularly check the diesel level, DG battery voltage, Low Lube oil Pressure (LLOP), High Coolant Temperature (HCT), High Water Temperature (HWT), and SMPS, and update the status to MCU. DCU is equipped with a battery charger to charge the generator battery, DCU is controlled by MCU through serial interface. MCU controls the DG unit switch ON or switch OFF function through DCU. DCU displays DG unit run hours, battery voltage, battery current, and temperature.
DG battery charger and DG controller (not shown in figure):"!) DG
battery charger is powered up through MCBs of both Alternating current distribution boards (ACDBs). This is to ensure supply to the battery charger even in case of failure of the AVR; 2) Automatic DG battery charger with constant current charging facility. Charger is suitable for charging the SMF/Conventional battery up to 150 ampere hours (even battery is in deep discharge); 3) DG unit controller with start, stop relays of 40 ampere rating and push button to start/stop the DG unit in manual mode; 4) remote Auto / Manual mode selection for DG unit switch on or switch off at DG control card in panel.

The AVR 110 continuously monitors the input voltage of the power
supply 118 and regulates the power supply given to the equipment. As
mentioned above, the AVR covers wide input voltage supply range of about 240
volts to about 485 volts (Phase to Phase) and 155 volt to 280 volt (Phase to
Neutral) and gives stable output voltage of 220 volts (+/- 10 percent). AVR 110
includes a built-in microcontroller, which corrects the output voltage in 10
milliseconds. AVR 110 is designed with a unique feature of zero voltage
correction technology. AVR 110 provides complete isolation to load from the
input voltage of the EB power supply. AVR is protected with Class B+C surge
arrestors. Class B+C surge arrestors provide the protection for load against
lightening and surges come on the input voltage of the EB power supply.
The "Master Control Unit" (MCU) (not shown in figure) of an AVR
primarily functions to monitor, display and control the AVR operation. MCU is interfaced with Power Switching Unit (PSU) to monitor input voltage of the EB power supply. As long as the mains supply voltage is within the predefined voltage range, the mains supply is given to transformer and load will be connected to AVR output voltage. When mains supply voltage is OFF or out of the predefined voltage range then, MCC will switch OFF the supply and displays the input over voltage or input low voltage and "Mains OFF" light emitting diode (LED) glows. MCU is interfaced with liquid crystal display (LCD) to display voltage, currents. LCD displays the AVR status messages. A keypad, LCD display interfaces are provided to the master control unit so that the user can view the displayed data interactively. It also measures and display output voltage power in kilowatts and kilowatt-hour.

In the system described herein and the schematic provided in FIG.
1, in one embodiment, two different output voltages are used to increase the efficiency of the usage of available power and minimizing the use of DG unit 114. The two output voltages include a regulated output voltage 138 and an unregulated output voltage 140 during the period when EB power 118 is available. The unregulated output voltage 140 may be fed to the SMPS. In various embodiments, the unregulated power may be fed to the SMPS, either in an internal manner or in an external manner 160 to ensure equal sharing of the load on all available phases. As shown in FIG. 1, the unregulated output voltage 152 from the load monitor 144 is passed to the SMPS 162 through an SMPS phase switcher 156.
Typically, as known in the art, SMPS is a system that includes
modular power rectifiers and a single master controller to achieve power factor equal to unity, and provide load sharing amongst the connected modules. In one embodiment, the SMPS 162 employed may be similar to a high efficiency SMPS which is typically used in telecom sites. The difference being in the number of power rectifier modules. In one embodiment, the system disclosed herein provides a continuous load sharing feature, by means of employing an SMPS that includes six rectifier modules or includes rectifier modules in multiples of six to achieve equal distribution on either one phase , two phases, or on three phases. In various embodiments, for step wise or digital load sharing as done by AVR 110 or for continuous or switching mode load sharing as done by Al 172; the number of rectifiers may be chosen as per the system and minimum switchable unit.

The unregulated output voltage 154 is fed as an input voltage to
the SMPS 162 through a SMPS phase switcher 156. The output voltage 164 of
the SMPS may have a specified number of outlets. In one embodiment, the
output voltage 164 of the SMPS will include a feature of Low Priority Load
Disconnect (LPLD). Further, the output voltage of the SMPS 166 may be
monitored by the DCDB 166 for each of the outlets 168 that may be connected to
the various equipments required, for example at a telecom site, to effectively
manage the power management system 100 disclosed herein.
In one embodiment, the regulated alternating current output
voltage 138 may be achieved through the AVR 110 in digital load sharing or stepwise load sharing schemes. In another embodiment, the regulated alternating current output voltage 138 may be achieved through an Al 172 using an advanced load inversion or continuous load balancing scheme. The advanced load inversion scheme may be either an internal scheme or an external scheme. One skilled in the art will appreciate that achieving a regulated alternating current output provides for continuous load sharing and this is achieved by the power management system 100 described herein.
In one embodiment, the AMF controller may include an algorithm
which monitors the voltage of the EB power supply 118 to ensure an adequate voltage as required by the various equipments that receive the EB power supply 118. As long as the direct current load requirements are met and the input voltage 132 supplied by the backup battery 132 does not discharge beyond a safe predetermined value, the power management system 100 disclosed herein will not provide a command for the DG unit 114 to be switched ON. The algorithm may also monitor shelter temperature. In certain embodiments, under certain situations where the temperature may be nearing emergency situations the DG unit 114 may be switched ON.
The phrase "all phases are substantially or reasonably evenly
loaded" may be further explained using the following example. Consider that a 25 kilo volt-ampere (KVA) load is available from the EB supply. Typically, the output voltage available from a traditional commercial source, the phases will provide a distributed load of 12, 13, 0 KVA to the equipments that use this output voltage load as input voltage load. However, using the power management system of the instant application, the three phases will have a substantially or reasonably evenly distributed load of 10, 8, and 7 KVA distributed across the three phases.
For example, if we have 2 AC Units, having a load of 3 KVA each,
and we have 1 SMPS with a 7 KVA load, total we have a total load of: 3+3+7=13 KVA load. The 13 KVA load is distributed as R with 4.5, Y with 4.5, and B with 4. Thus, preferably a single phase motor is employed, so that even single phase EB can be employed before a need to switch on the DG arises. On the other hand, in PIU's available in the art, if we have 3 output voltages and we have the 2 AC unit and 1 SMPS unit, Output voltage 1 one AC unit - one phase connected to one AC unit; Output voltage 2 another AC unit -second phase connected to second AC unit; and Output voltage 3, 4, 5 SMPS-third phase is connected to SMPS. Thus an uneven load of 3, 3, and 7 KVA is connected to the first AC unit, second AC unit, and SMPS respectively. In the power management system 100 described herein, the AC unit and SMPS inputs are connected, and the available load is reasonably equally distributed over the three equipments.

The power management system 100 described herein may also
be referred to as a power monitoring unit (PMU) or a power interfacing unit (PIU). The primary function of the power management system includes monitoring EB supply and stabilizing EB supply output voltage 118 in locales where EB supply 118 is not equal over all phases while at the same time regulating and minimizing DG unit usage. The power management system of the instant invention, stabilizes EB output voltage, chooses best phase for the equipments, i.e., the AC unit, the SMPS charger, etc., and thus delays DG unit start-up which may otherwise occur due to non-uniform loads being supplied to the equipment in addition to complete failure of EB supply. Additionally, as discussed above, the power management system assists in distributing the available power output voltage substantially evenly across the available phases before feeding them as input voltages to the various equipments, i.e., even if the EB output voltage has only one phase or two phases available, the output voltage is substantially evenly distributed before being fed to the equipment. As used herein, the phrase "substantially evenly distributed" means that the available output voltage load from the EB is not exactly evenly distributed, but distributed in a nearly balanced manner. The load may be distributed as per availability to a certain phase that is connected to a certain equipment as per the power requirement of the equipment. Care must be taken during installation to ensure that the right output voltage is connected for the right requirement and hence the appropriate equipment. Thus, if only one phase is available, then a single large load is directed to one phase. In certain instances, wherever possible single phase motors are employed, so the need for three phases from EB supply may be minimized.

Thus, power management system 100 described herein operates
to provide load distribution over available number of phases, i.e., if three phases
available the available load is distributed over three phases, if two phases are
available the available load is distributed over two phases, if one phase is
available the available load is diverted to this one available phase.
As mentioned above, in currently available power management
systems, balancing is not an intent. In current PIU's if one phase is not working, other phases generate the power normally, the output voltage is the same, while at the same time the input voltage is distorted. Also, as described above, one of the strategies being proposed by the Indian Government is to balance the available power load on available phases and this will eventually be required to enable load sharing. The load sharing requirement may eventually become a statutory requirement.
In one embodiment, the load balancing and distribution described
herein may be applicable for single phase motors. The power management
system may function with respect to any kind of voltage stabilizer. For example,
if the available output voltage load is a single phase load, the equipment may be
run with a single phase. However, in certain instances, for example, for
transformers, where multiphase load is required, and if the transformer is running
with two phases, R and Y, output voltage is controlled, the transformer may be
connected between R and N, and output voltage can be regulated.
The power management system 100 described herein has certain
additional features and advantages. In embodiments, where an AC unit (one of the equipments to which the load 168 is supplied, not shown in figure) is switched on either by a command received from the power management system 100 or

based on the temperature cycle, in various embodiments, the load balancing may be achieved digitally or the load balancing may be achieved inherently under the continuous balancing system discussed herein.
In another embodiment, the system described herein in addition to
provide a load sharing on EB power supply may also advantageously provide a load sharing on DG unit output voltage. This feature additionally helps in improving the efficiency of the DG unit.
In still yet another embodiment, the AMF 112, the AVR 110 or the
Al 172, and the phase switcher 116 may be connected with individual by pass switches i.e., the AMF bypass 124 and the AVR bypass 126, for ease of maintenance and trouble shooting. if no bypass is employed, and if one unit gets corrupted, to remove the one corrupted unit, all wires need to be disconnected and all units would need to be dislodged. A single switch is provided to bypass the units which will assist in bypassing the faulty unit and connecting the working units, thus making it easy to pull out the faulty unit without disrupting the working units.
The power management system, in certain embodiments also
provides fuel level monitoring, and provides fuel level display. The fuel level may be displayed using a multi-colored bar-graph display of the fuel level using YRG (yellow, red, and green) colors.
In additional embodiments, the system disclosed herein may be
employed to provide regulated AC output voltage from renewable energy sources including solar and wind sources. The system may be readily interfaced with solar or wind charge controller and the continuous load balancer with inversion scheme assists in providing a regulated alternating current output

One additional advantage of the power management system
includes the placement of the AMF panel. Traditionally the AMF panel is placed over a DG unit. The DG unit is typically placed outside the confined space that houses the equipments. The external location of the AMF at times may result in tampering of the AMF unit and pilferage of diesel from the DG unit. The power management system combines the AMF and the AVR and the entire unit is placed within the confined space, thus minimizing the possibilities of tampering with the units.
Yet other embodiments include employing the system to provide
general packet radio service (GPRS) remote monitoring, battery health monitoring, controlling free-cooling technique that employs ambient air, and advanced fuel optimisation control.
The foregoing embodiments meet the overall objectives of this
disclosure as summarized above. However, it will be clearly understood by those skilled in the art that the foregoing description has been made in terms only of the most preferred specific embodiments. Therefore, many other changes and modifications clearly and easily can be made that are also useful improvements and definitely outside the existing art without departing from the scope of the present disclosure, indeed which remain within its very broad overall scope, and which disclosure is to be defined over the existing art by the appended claims.

We Claim:
1. A power management system comprising:
an automatic static voltage regulator unit;
an automatic mains failure unit; and
a phase switcher;
wherein the automatic static voltage regulator unit is configured to continuously monitor an input vottage provided by a power supply and regulate the power supply given to an equipment using the phase switcher by balancing the power supply in a step-wise or digital manner; and
wherein the automatic mains failure unit is configured to continuously monitor an output voltage from the automatic static voltage regulator unit and the performance of a diesel power generator.
2. The power management system of claim 1, further comprising an automatic static voltage regulator unit bypass configured to directly connect the power supply to the automatic mains failure unit.
3. The power management system of claim 1, further comprising an automatic mains failure unit bypass configured to directly connect the diesel generator unit to a load monitor.
4. The power management system of claim 1, further comprising an advanced inverter unit which is configured to continuously monitor an input voltage provided by a direct current distribution board power supply through a switch mode power supply and regulate the direct current distribution board power supply given to an equipment by continuously balancing the input voltage.

5. The power management system of claim 3, wherein an output voltage provided by the advanced inverter unit is passed through the automatic mains failure unit through an automatic static voltage regulator unit bypass, and the automatic mains failure unit is configured to monitor the output voltage provided by the advanced inverter unit.
6. A power management system comprising:
an advanced inverter unit;
an automatic mains failure unit; and
a switch mode power supply;
wherein the advanced inverter unit is configured to continuously monitor an input voltage provided by a direct current distribution board power supply through the switch mode power supply and regulate the direct current distribution board power supply given to an equipment by continuously balancing the input voltage; and
wherein the automatic mains failure unit is configured to continuously monitor an output voltage from the advanced inverter unit and the performance of a diesel power generator.
7. The power management system of claim 5, further comprising an
automatic static voltage regulator unit and a phase switcher, wherein the
automatic static voltage regulator unit is configured to continuously monitor an
input voltage provided by a power supply and regulate the power supply given to
an equipment using the phase switcher by balancing the power supply in a step
wise or digital manner.

8. The power management system of claim 5, further comprising an automatic static voltage regulator bypass configured to directly connect the input power supply to the automatic mains failure unit and an automatic mains failure bypass unit configured to directly connect the diesel generator unit to a load monitor.
9. A method for managing power comprising:
providing a power management system comprising;
an automatic static voltage regulator unit;
an automatic mains failure unit; and
a phase switcher;
using the automatic static voltage regulator unit to continuously monitor an input voltage provided by a power supply and regulate the power supply given to an equipment using the phase switcher by balancing the power supply in a step-wise or digital manner, and
using the automatic mains failure unit to continuously monitor an output voltage from the automatic static voltage regulator unit and the performance of the diesel power generator.
10. A method of regulating a diesel generator unit comprising:
providing a power management system comprising; an advanced inverter unit; an automatic mains failure unit; and a switch mode power supply;
using the advanced inverter unit to continuously monitor an input voltage provided by a direct current distribution board power supply through the switch

mode power supply and regulate the direct current distribution board power supply given to an equipment by continuously balancing the input voltage; and
using the automatic mains failure unit to continuously monitor an output voltage from the advanced inverter unit and the performance of the diesel power generator.