Claims:1. A power factor controller comprising:
a voltage signal conditioning unit (102) configured to measure real time voltage across a power system;
a current signal conditioning unit (104) configured to measure current input from input power line of the power system; and
a microcontroller (106) configured to
receive the measured voltage and the measured current;
calculate required reactive power (Kvar) by the power system to achieve a desired power factor (PF) based on the measured voltage and the measured current input and an apparent power of the power system;
select a combination of capacitors or inductors available in a reactive power bank (120) to supply to the required reactive power while ensuring minimum switching of the capacitors and the inductors of the reactive power bank to achieve the desired power factor; and
generate switching output signals to be executed by relays/transistors of the selected capacitors and inductors.

2. The power factor controller of claim 1, wherein the power factor controller is configured to receive the desired power factor for the power system through an external I/O interface.

3. The power factor controller of claim 1, wherein the microcontroller (106) is further configured to:
receive actual PF of the power system;
compare the actual PF with the desired PF;
determine a gradual increase in reactive power;
select combination of capacitors or inductors to gradually increase the reactive power; and
generate switching output signals to be executed by relays /transistors, wherein the gradual increase of required power (Kvar) is calculated as
?kvar = P * [Tan(?1)-Tan(?2)]; where P is actual Power, ?1 corresponds to the updated PF and ?2 to the desired PF.

4. The power factor controller of claim 1, wherein the microcontroller (106) is configured to ensure equal utilization of capacitors and inductors present at a particular step inside the power bank(120) while selecting the combination of capacitors and inductors to be used to provide the required reactive power.

5. The power factor controller of claim 1, wherein the power factor controller further comprises a LED based indicator (110) to indicate leading PF or lagging PF.

6. The power factor controller of claim 1, wherein the power factor controller further comprises a display (112) to display one or a combination of the measured voltage, the measured current, the real time power, the actual power factor, the desired power factor and the required reactive power.

7. The power factor controller of claim 1, wherein the power factor controller further comprises an input/output interface (114) to send and receive one or combination of the measured voltage, the measured current, the real time power, the actual power factor, the desired power factor and the required reactive power.

8. A method to correct power factor through reactive power to achieve a desired power factor , the method comprising steps of
measuring real time voltage and current in a power system;
receiving,at a microcontroller, the measured voltage and measured current input;
calculating by the microcontroller, a required reactive power (Kvar) by a power system to achieve the desired power factor based on the measured voltage and the measured current input and an apparent power;
selecting, by the microcontroller, a combination of capacitors or inductors, available in a reactive power bank to supply to the required reactive power while ensuring minimum switching of capacitors and inductors of the reactive power bank to achieve the desired power factor; and
generating, by the microcontroller, switching output signals to be executed by relays/transistors of the determined capacitors and inductors.

9. The method of claim 8, wherein the microcontroller ensures equal utilization of capacitors and inductors present at a particular step inside the power bank(120) while selecting the combination of capacitors and inductors to be used to provide the required reactive power.

10. The method of claim 8, wherein the microcontroller (106) further performs the steps of:
receiving actual PF of the power system;
comparing the actual PF with the desired PF;
determining a gradual increase in reactive power;
selecting combination of capacitors or inductors to gradually increase the reactive power; and
generating switching output signals to be executed by relays /transistors, wherein the gradual increase of required power (Kvar) is calculated as
?kvar = P * [Tan(?1)-Tan(?2)]; where P is actual Power, ?1 corresponds to the updated PF and ?2 to the desired PF
, Description:TECHNICAL FIELD
[0001] The present disclosure generally relates to the field of electronic power system. In particular, the present disclosure relates to reactive power management using intelligent control by a power factor controller.

BACKGROUND
[0002] Background description includes information that may be useful in understanding the present invention. It is not an admission that any of the information provided herein is prior art or relevant to the presently claimed invention, or that any publication specifically or implicitly referenced is prior art.
[0003] Power factor of an AC electrical power system is defined as the ratio of real/actual power flowing to a load to an apparent power in the circuit, and is a dimensionless number, generally in the closed interval of -1 to 1. A power factor of less than one means that the voltage and current waveforms are not in phase, reducing the instantaneous product of the two waveforms (V x I). Real/actual power is the capacity of the circuit for performing work in a particular time. Apparent power is the product of the current and voltage of the circuit. Due to energy stored in the load and returned to the source, or due to a non-linear load that distorts the wave shape of the current drawn from the source, the apparent power may be greater than the real power. A negative power factor occurs when the device (which is normally the load) generates power, which then flows back towards the source, which is normally considered the generator.
[0004] In an electric power system, a load with a low power factor draws more current than a load with a high power factor for the same amount of useful power transferred. It is desired to achieve an electrical power system with high power factor, ideally a power factor near unity (i.e. 1).
[0005] Linear loads(such as induction motors) with low power factor can be corrected with a passive network of capacitors or inductors. Non-linear loads, such as rectifiers, distort the current drawn from the power system. In such cases, active or passive power factor correction may be used to counteract the distortion and raise the power factor. The devices for correction of the power factor may be at a central substation, spread out over a distribution system, or built into power-consuming equipment.
[0006] Electrical power system where most of the loads are inductive loads, such as electrical drive, elevator, air conditioner etc, the power factor of the power system shifts away from unity and ultimately decreases efficiency of the power system. To improve the power factor, there requires reactive power compensation.
[0007] Power factor correction may be achieved by adding or removing reactive components such as capacitors or inductors to the power system. Adding capacitors or inductors to the system may bring the power factor closer to unity. Controlling the reactive power can be achieved by specific control algorithm implemented through a power factor (PF) controller. Existing PF controllers controls the reactive power to correct the power factor by turning ON and OFF, capacitors and inductors in a particular manner. Most of the existing power factor controllers use linear switching or circular switching. It’s possible that some capacitors are used very frequency while other don’t get used and hence may lead to early failure of frequently used capacitors.
[0008] There exist needs for a power factor controller and method for enabling reactive power management using intelligent control of the reactive power. The PF controller and method is required to achieve the desired power factor by reactive power management. The PD controller and method is required to ensure minimum switching of the reactive components (capacitors or inductors) to achieve the desired power factor.
[0009] All publications herein are incorporated by reference to the same extent as if each individual publication or patent application were specifically and individually indicated to be incorporated by reference. Where a definition or use of a term in an incorporated reference is inconsistent or contrary to the definition of that term provided herein, the definition of that term provided herein applies and the definition of that term in the reference does not apply.
[0010] In some embodiments, the numbers expressing quantities of ingredients, properties such as concentration, reaction conditions, and so forth, used to describe and claim certain embodiments of the invention are to be understood as being modified in some instances by the term “about”. Accordingly, in some embodiments, numerical parameters set forth in the written description are approximations that can vary depending upon the desired properties sought to be obtained by a particular embodiment. In some embodiments, the numerical parameters should be construed in light of the number of reported significant digits and by applying ordinary rounding techniques. Notwithstanding that, the numerical ranges and parameters setting forth the broad scope of some embodiments of the invention are approximations, the numerical values set forth in the specific examples are reported as precisely as practicable. The numerical values presented in some embodiments of the invention may contain certain errors necessarily resulting from the standard deviation found in their respective testing measurements.
[0011] As used in the description herein and throughout the claims that follow, the meaning of “a,” “an,” and “the” includes plural reference unless the context clearly dictates otherwise. Also, as used in the description herein, the meaning of “in” includes “in” and “on” unless the context clearly dictates otherwise.
[0012] The recitation of ranges of values herein is merely intended to serve as a shorthand method of referring individually to each separate value falling within the range. Unless otherwise indicated herein, each individual value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g. “such as”) provided with respect to certain embodiments herein is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention otherwise claimed. No language in the specification should be construed as indicating any non-claimed element essential to the practice of the invention.
[0013] Groupings of alternative elements or embodiments of the invention disclosed herein are not to be construed as limitations. Each group member can be referred to and claimed individually or in any combination with other members of the group or other elements found herein. One or more members of a group can be included in, or deleted from, a group for reasons of convenience and/or patentability. When any such inclusion or deletion occurs, the specification is herein deemed to contain the group as modified thus fulfilling the written description of all groups used in the appended claims.

OBJECTS OF THE INVENTION
[0014] It is an object of the present disclosure to provide a power factor controller to achieve a high power factor.
[0015] An object of the present disclosure is to provide a power factor controller and method for enabling reactive power management using intelligent control of the reactive power.
[0016] An object of the present disclosure is to provide a power factor controller and method for reactive power management that can control switching ON/OFF on capacitors and inductors that provide reactive power.
[0017] An object of the present disclosure is to provide a reactive power based actual performance of the power distribution system/circuit.
[0018] With these and other objects, advantages and features of the invention may become apparent and the nature of the invention may be more clearly understood by reference to the following detailed description of the invention, the appended claims and the drawings attached hereto.

SUMMARYOF THE INVENTION
[0019] The present disclosure generally relates to the field of power factor correction in electronic power system. In particular, the present disclosure relates to reactive power management using intelligent control by a power factor controller. Aspects of the repent disclosure provides a PF controller and a method for enabling reactive power management using intelligent control of the reactive power. The PF controller and method of present disclosure ensure minimum switching of the reactive components (capacitors or inductors) to achieve the desired power factor. The PF controller and method of present disclosure can enable dynamic power factor correction.
[0020] An aspect of the present disclosure provides a power factor controller configured to correct power factor through reactive power management to achieve a desired power factor, for example a power factor near unity. The power factor controller can include
a voltage signal conditioning unit configured to measure real time voltage across a power system, a current signal conditioning unit configured to measure current input from the power line of the power system, a microcontroller configured to receive the measured voltage and measure current input, calculate a required reactive power (Kvar) by a power system to achieve a desired power factor based on the measured voltage and measured current input and apparent power, select combination of capacitors or inductors, available in a reactive power bank, to supply to the required reactive power, while ensuring minimum switching of the capacitors and inductors to achieve the desired power factor, and generate switching output signals to be executed by relays/transistors of the determined capacitors and inductors. In an exemplary implementation, the combination of capacitors and inductors can be determined in such as way that the number of capacitors and inductors to be switched can be minimized. In an exemplary implementation, microcontroller of the PF controller can be configured to ensure equal utilization of capacitors and inductors present at a particular step, while determining the combination of capacitors and inductors to be used to provide the required reactive power. In an exemplary implementation, the PF controller can be configured to monitor health of each available capacitor and inductor of the reactive power bank and select the combination of capacitors or inductors based on the health of available capacitors and indictors of the reactive power bank. In an exemplary implementation, value of the capacitor or inductors can be connected to any step in any order. In an exemplary implementation, switching time of the capacitors and inductors for selecting switching sequence can also be used a parameter to select the combination of capacitors and inductors.
[0021] In an exemplary implementation, the PF controller can include a LED based indicator to indicate leading PF or lagging PF. A lagging PF signifies that the load is inductive, as the load will “consume” reactive power, and therefore the reactive power is positive as reactive power travels through the circuit and is “consumed” by the inductive load. A leading power factor signifies that the load is capacitive, as the load “supplies” reactive power, and therefore the reactive power is negative as reactive power is being supplied to the circuit.
[0022] In an aspect, the PF controller can include a display that can provide various electrical parameters including but not limiting to measured voltage, measured current, real time power, required reactive power, and desired power factor. In an exemplary implementation, the PF controller can include input/output interface, for example an HDMI or USB port, for receiving the electrical parameters from another device or user or transfer values of the electrical parameters to an external device.
[0023] In an exemplary implementation, the PF controller can be configured to provide conditional PF correction, wherein the microcontroller can be configured to determine actual PF of the power system based on the measured current and the measured voltage and apparent power, compare the actual PF with the desired PF and determine the required reactive power, wherein the required power (Kvar) can be calculated using formula below
?kvar = P * [Tan(?1)-Tan(?2)]; Wherein, P is actual Power (P=measured voltage * measured current), ?1 corresponds to present PF and ?2 to the desired PF.
[0024] An aspect of the present disclosure provides a method to correct power factor through reactive power to achieve a desired power factor. The method includes steps of measuring real time voltage and current in a power system, receiving, at a microcontroller, the measured voltage and measured current input , calculating by the microcontroller a required reactive power (Kvar) by a power system to achieve a desired power factor based on the measured voltage and measured current input and apparent power, determining, by the microcontroller, combination of capacitors or inductors, available in a reactive power bank, to supply to the required reactive power, while ensuring minimum switching of the capacitors and inductors to achieve the desired power factor, and generating, by the microcontroller, switching output signals to be executed by relays/transistors of the determined capacitors and inductors.
[0025] In an exemplary implementation, the combination of capacitors and inductors can be determined in such as way that the number of capacitors and inductors to be switched can be minimized. In an exemplary implementation, microcontroller of the PF controller can be configured to ensure equal utilization of capacitors and inductors present at a particular step, while determining the combination of capacitors and inductors to be used to provide the required reactive power. In an exemplary implementation, the PF controller can be configured to monitor health of each available capacitor and inductor of the reactive power bank and select the combination of capacitors or inductors based on the health of available capacitors and indictors of the reactive power bank. In an exemplary implementation, value of the capacitor or inductors can be connected to any step in any order.
[0026] Other features of embodiments of the present invention will be apparent from accompanying drawings and from detailed description that follows.

BRIEF DESCRIPTION OF THE DRAWINGS
[0027] In the Figures, similar components and/or features may have the same reference label. Further, various components of the same type may be distinguished by following the reference label with a second label that distinguishes among the similar components. If only the first reference label is used in the specification, the description is applicable to any one of the similar components having the same first reference label irrespective of the second reference label.
[0028] FIG. 1 is an exemplary block diagram of a power factor controller in accordance with an embodiment of the present disclosure.
[0029] FIG. 2 is an exemplary operations performed by the power factor controller in accordance with an embodiment of the present disclosure.
[0030] FIG. 3 illustrated exemplary flow of method to correct power factor through reactive power to achieve a desired power factor in accordance with an embodiment of the present disclosure.

DETAILED DESCRIPTION OF THE INVENTION
[0031] The following is a detailed description of embodiments of the disclosure depicted in the accompanying drawings. The embodiments are in such detail as to clearly communicate the disclosure. However, the amount of detail offered is not intended to limit the anticipated variations of embodiments; on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the present disclosure as defined by the appended claims.
[0032] Each of the appended claims defines a separate invention, which for infringement purposes is recognized as including equivalents to the various elements or limitations specified in the claims. Depending on the context, all references below to the "invention" may in some cases refer to certain specific embodiments only. In other cases it will be recognized that references to the "invention" will refer to subject matter recited in one or more, but not necessarily all, of the claims.
[0033] Various terms as used herein are shown below. To the extent a term used in a claim is not defined below, it should be given the broadest definition persons in the pertinent art have given that term as reflected in printed publications and issued patents at the time of filing.
[0034] Embodiments of the present disclosure include various steps, which will be described below. The steps may be performed by hardware components or may be embodied in machine-executable instructions, which may be used to cause a general-purpose or special-purpose processor programmed with the instructions to perform the steps. Alternatively, steps may be performed by a combination of hardware, software, firmware and/or by human operators.
[0035] If the specification states a component or feature “may”, “can”, “could”, or “might” be included or have a characteristic, that particular component or feature is not required to be included or have the characteristic.
[0036] Although the present disclosure has been described with the purpose to automatically achieve desired power factor in a electric transmission system, it should be appreciated that the same has been done merely to illustrate the disclosure in an exemplary manner and any other purpose or function for which the explained structure or configuration can be used, is covered within the scope of the present disclosure.
[0037] Exemplary embodiments will now be described more fully hereinafter with reference to the accompanying drawings, in which exemplary embodiments are shown. This disclosure may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. These embodiments are provided so that this disclosure will be thorough and complete and will fully convey the scope of the disclosure to those of ordinary skill in the art. Moreover, all statements herein reciting embodiments of the disclosure, as well as specific examples thereof, are intended to encompass both structural and functional equivalents thereof. Additionally, it is intended that such equivalents include both currently known equivalents as well as equivalents developed in the future (i.e., any elements developed that perform the same function, regardless of structure).
[0038] Thus, for example, it will be appreciated by those of ordinary skill in the art that the diagrams, schematics, illustrations, and the like represent conceptual views or processes illustrating systems and methods embodying this disclosure. The functions of the various elements shown in the figures may be provided through the use of dedicated hardware as well as hardware capable of executing associated software. Their function may be carried out through the operation of program logic, through dedicated logic, through the interaction of program control and dedicated logic, or even manually, the particular technique being selectable by the entity implementing this disclosure. Those of ordinary skill in the art further understand that the exemplary hardware, software, processes, methods, and/or operating systems described herein are for illustrative purposes and, thus, are not intended to be limited to any particular named.
[0039] Embodiments of the present disclosure generally relates to the field of power factor correction in electronic power system. In particular, the present disclosure relates to reactive power management using intelligent control by a power factor controller. Aspects of the repent disclosure provides a PF controller and a method for enabling reactive power management using intelligent control of the reactive power. The PF controller and method of present disclosure ensure minimum switching of the reactive components (capacitors or inductors) to achieve the desired power factor. The PF controller and method of present disclosure can enable dynamic power factor correction.
[0040] An embodiment of the present disclosure provides a power factor controller configured to correct power factor through reactive power management to achieve a desired power factor, for example a power factor near unity. The power factor controller can include
a voltage signal conditioning unit configured to measure real time voltage across a power system, a current signal conditioning unit configured to measure current input from the power line of the power system, a microcontroller configured to receive the measured voltage and measure current input , calculate a required reactive power (Kvar) by a power system to achieve a desired power factor based on the measured voltage and measured current input and apparent power, select combination of capacitors or inductors, available in a reactive power bank, to supply to the required reactive power, while ensuring minimum switching of the capacitors and inductors to achieve the desired power factor, and generate switching output signals to be executed by relays/transistors of the determined capacitors and inductors. In an exemplary implementation, the combination of capacitors and inductors can be determined in such as way that the number of capacitors and inductors to be switched can be minimized. In an exemplary implementation, microcontroller of the PF controller can be configured to ensure equal utilization of capacitors and inductors present at a particular step, while determining the combination of capacitors and inductors to be used to provide the required reactive power. In an exemplary implementation, the PF controller can be configured to monitor health of each available capacitor and inductor of the reactive power bank and select the combination of capacitors or inductors based on the health of available capacitors and indictors of the reactive power bank. In an exemplary implementation, value of the capacitor or inductors can be connected to any step in any order. In an exemplary implementation, switching time of the capacitors and inductors for selecting switching sequence can also be used a parameter to select the combination of capacitors and inductors.
[0041] In an exemplary implementation, the PF controller can include a LED based indicator to indicate leading PF or lagging PF. A lagging PF signifies that the load is inductive, as the load will “consume” reactive power, and therefore the reactive power is positive as reactive power travels through the circuit and is “consumed” by the inductive load. A leading power factor signifies that the load is capacitive, as the load “supplies” reactive power, and therefore the reactive power is negative as reactive power is being supplied to the circuit.
[0042] In an embodiment, the PF controller can include a display that can provide various electrical parameters including but not limiting to measured voltage, measured current, real time power, required reactive power, and desired power factor. In an exemplary implementation, the PF controller can include input/output interface, for example an HDMI or USB port, for receiving the electrical parameters from another device or user or transfer values of the electrical parameters to an external device.
[0043] In an exemplary implementation, the PF controller can be configured to provide conditional PF correction, wherein the microcontroller can be configured to determine actual PF of the power system based on the measured current and the measured voltage and apparent power, compare the actual PF with the desired PF and determine the required reactive power, wherein the required power (Kvar) can be calculated using formula below
?kvar = P * [Tan(?1)-Tan(?2)]; Wherein, P is actual Power (P=measured voltage * measured current), ?1 corresponds to present PF and ?2 to the desired PF.
[0044] An embodiment of the present disclosure provides a method to correct power factor through reactive power to achieve a desired power factor. The method includes steps of measuring real time voltage and current in a power system, receiving, at a microcontroller, the measured voltage and measured current input , calculating by the microcontroller a required reactive power (Kvar) by a power system to achieve a desired power factor based on the measured voltage and measured current input and apparent power, determining, by the microcontroller, combination of capacitors or inductors, available in a reactive power bank, to supply to the required reactive power, while ensuring minimum switching of the capacitors and inductors to achieve the desired power factor, and generating, by the microcontroller, switching output signals to be executed by relays/transistors of the determined capacitors and inductors.
[0045] In an exemplary implementation, the combination of capacitors and inductors can be determined in such as way that the number of capacitors and inductors to be switched can be minimized. In an exemplary implementation, microcontroller of the PF controller can be configured to ensure equal utilization of capacitors and inductors present at a particular step, while determining the combination of capacitors and inductors to be used to provide the required reactive power. In an exemplary implementation, the PF controller can be configured to monitor health of each available capacitor and inductor of the reactive power bank and select the combination of capacitors or inductors based on the health of available capacitors and indictors of the reactive power bank. In an exemplary implementation, value of the capacitor or inductors can be connected to any step in any order.
[0046] FIG. 1 is an exemplary block diagram of a power factor controller in accordance with an embodiment of the present disclosure. As shown in FIG. 1, the power factor controller 100 can include a voltage signal conditioning unit 102 configured to measure real time voltage across power system, a current signal conditioning unit 104 configured to measure current input from input power line of the power system, a microcontroller 106 configured to receive the measured voltage and measure current, calculate a required reactive power (Kvar) by the power system to achieve a desired power factor based on the measured voltage and measured current input and apparent power, determine combination of capacitors or inductors, available in a reactive power bank 120, to supply to the required reactive power, while ensuring minimum switching of the capacitors and inductors to achieve the desired power factor, and generate switching output signals 108 to be executed by relays/transistors of the determined/selected capacitors and inductors. In an exemplary implementation, the microcontroller 106 can be power by a power supply unit 116 that receives power through linear transformer 118.
[0047] In an exemplary implementation, the PF controller 100 can be configured to provide conditional PF correction, wherein the microcontroller can be configured to determine actual PF of the power system based on the measured current and the measured voltage and apparent power, compare the actual PF with the desired PF and determine the required reactive power, wherein the required power (Kvar) can be calculated using formula below
?kvar = P * [Tan(?1)-Tan(?2)];
Wherein, P is actual Power (P=measured voltage * measured current), ?1 corresponds to present PF and ?2 to the desired PF.
[0048] In an exemplary implementation, the combination of capacitors and inductors can be selected in such as way that the number of capacitors and inductors to be switched can be minimized. In an exemplary implementation, microcontroller 106 can be configured to ensure equal utilization of capacitors and inductors present at a particular step inside the power bank 120, while selecting the combination of capacitors and inductors to be used to provide the required reactive power. In an exemplary implementation, the PF controller 100 can be configured to monitor health of each available capacitor and inductor of the reactive power bank 120 and select the combination of capacitors or inductors based on the health of available capacitors and indictors of the reactive power bank 120. In an exemplary implementation, value of the capacitor or inductors can be connected to any step in any order.
[0049] In an exemplary implementation, the PF controller 100 can further include a LED based indicator 110 to indicate leading PF or lagging PF. A lagging PF signifies that the load is inductive, as the load will “consume” reactive power, and therefore the reactive power is positive as reactive power travels through the circuit and is “consumed” by the inductive load. A leading power factor signifies that the load is capacitive, as the load “supplies” reactive power, and therefore the reactive power is negative as reactive power is being supplied to the circuit.
[0050] In an aspect, the PF controller 100 can further include a display unit112 that can display various electrical parameters including but not limiting to measured voltage, measured current, real time power, required reactive power, and desired power factor. In an exemplary implementation, the PF controller 100 can include input/output (I/O) interface 114, for example an HDMI or USB port, for receiving the electrical parameters from another device or user, and transfer values of the electrical parameters to an external device.
[0051] In an exemplary implementation, the microcontroller 108 can be configured to generate switching output signal 108 for switching ON/OFF the selected capacitors/inductors f the power bank 120. The microcontroller 108 can calculate the required reactive power be connected to the power system in order to achieve the desired PF and then deciding on a combination of capacitors/inductors that can supply this required reactive power.
[0052] The PF controller 100 ensures minimum switching to achieve desired power factor while providing equal capacitor/inductor utilization of same step capacitors, capacitor health check monitoring, and step exchange feature for finer control. The PF controller 100 of the present disclosure does not put any restriction on the size and sequence of connected capacitor steps as against prior art. Any value of capacitor may be connected to any step in any order by the PF controller 100.
[0053] In an exemplary implementation, Voltage Inputs & Current input from external primary CT can be fed to the signal conditioning circuit, such as voltage conditioning circuit 102 and current conditioning circuit 104, which converts and translates the voltage level/current value in measurable ADC voltage range. The microcontroller 106 can compute electrical parameters like measured voltage, measured current, measured power (measured current * measured voltage), apparent power, actual power factor, required reactive power, THD etc. The microcontroller 106 can generate switching output signal 108 to operate relays/Transistors to supply or remove capacitor compensation based on required reactive power (kvar).
[0054] FIG. 2 is an exemplary operations performed by the power factor controller in accordance with an embodiment of the present disclosure. As shown in FIG. 2, a target power factor (PF) 202 in form of cosine value (Cos?2) can be set in a PF controller for a power system. The target power factor 202 can be set of a user for a power system and the target power factor 202 can be stored in memory of the PF controller. As shown at block 206, the PF controller can measure electrical parameters, actual power (P), apparent power (Q), power factor (PF) by continuously monitoring the power system. Based on the target PF set by block 202 and actual PF measured by the block 206, the microcontroller can determine the required reactive power (Kvar) as shown in block 204 and can gradually increase the reactive power. The gradual increase in required reactive power ?Kvar can be calculated using formula, for example
?kvar = P * [Tan(?1)-Tan(?2)];
Wherein, P is actual Power (P=measured voltage * measured current), ?1 corresponds to present PF and ?2 to the desired PF.
[0055] The PF controller tries to regulate PF within a tolerance limit around the target PF, also referred interchangeably as desired PF. An intelligent control algorithm running on the microcontroller tries to ensure equal utilization of steps so that one overused step capacitor does not deteriorate too soon. In order to achieve PF closer to the target PF the microcontroller may sometime disconnect a connected step and replace it with a step of more appropriate size (Step Exchange). In an exemplary implementation, the PF controller also tries to minimize the total number of switching so as to minimize transients in the power line. To control the response time of the control loop (and ensuring that frequent switching/hunting does not happen) a control loop sensitivity time setting can be employed by the PF controller. Further, in an exemplary implementation, the PF controller can make sure that any capacitor of the power bank, before it’s connected to provide reactive power, gets enough time to discharge to a safe voltage limit.
[0056] As shown in FIG. 2, the block 208 can generates the control signal, also interchangeably used as switching output signal, to update the actual power factor of the power system. The microcontroller can select best combination of capacitors from the power bank to be connected. The microcontroller also ensures that the power bank should be completely discharged or disconnected from the power line and has less number of switching cycles. For equal step size capacitor banks in power system, control logic selects the capacitors which are least used. If step exchange is enabled & target PF is not reached with switched steps, then control logic again checks for appropriate capacitor bank to replace with switched one.
[0057] In an exemplary implementation, the microcontroller can be configured to identify/determine/select the combination of capacitors or inductors and their switching sequence. When the required power factor Kvar tend to zero, (indicating tolerate=c/k), equal steps can be taken, and capacitors and inductors can be used equally. In such case the minimum switching of the capacitors and inductors may be required. While selecting the capacitors and inductors, the microcontroller can take several factor into consideration including but not limiting to health status of the capacitors and inductors, and estimated switching time to achieve the desired PF/ reactive power.
[0058] FIG. 3 illustrated exemplary flow of method to correct power factor through reactive power to achieve a desired power factor in accordance with an embodiment of the present disclosure. The method includes steps of measuring real time voltage and current in a power system as shown at step 302, receiving, at a microcontroller, the measured voltage and measured current input as shown step 304, calculating by the microcontroller a required reactive power (Kvar) by the power system to achieve a desired power factor based on the measured voltage and measured current input and apparent power as shown at step 306, selecting, by the microcontroller, combination of capacitors or inductors, available in a reactive power bank, to supply to the required reactive power as shown at step 308, while ensuring minimum switching of the capacitors and inductors to achieve the desired power factor, and generating, by the microcontroller, switching output signals to be executed by relays/transistors of the determined capacitors and inductors as shown at step 310.
[0059] In an exemplary implementation, the combination of capacitors and inductors can be determined in such as way that the number of capacitors and inductors to be switched can be minimized. In an exemplary implementation, microcontroller of the PF controller can be configured to ensure equal utilization of capacitors and inductors present at a particular step, while determining the combination of capacitors and inductors to be used to provide the required reactive power. In an exemplary implementation, the PF controller can be configured to monitor health of each available capacitor and inductor of the reactive power bank and select the combination of capacitors or inductors based on the health of available capacitors and indictors of the reactive power bank. In an exemplary implementation, value of the capacitor or inductors can be connected to any step in any order.
[0060] As one may appreciate, the PF controller and method of present disclosure can provide correction of the power factor may be at a central substation, spread out over a distribution system, or built into power-consuming equipment, referred here interchangeably as power system.
[0061] It should be apparent to those skilled in the art that many more modifications besides those already described are possible without departing from the inventive concepts herein. The inventive subject matter, therefore, is not to be restricted except in the spirit of the appended claims. Moreover, in interpreting both the specification and the claims, all terms should be interpreted in the broadest possible manner consistent with the context. In particular, the terms “comprises” and “comprising” should be interpreted as referring to elements, components, or steps in a non-exclusive manner, indicating that the referenced elements, components, or steps may be present, or utilized, or combined with other elements, components, or steps that are not expressly referenced. Where the specification claims refers to at least one of something selected from the group consisting of A, B, C ….and N, the text should be interpreted as requiring only one element from the group, not A plus N, or B plus N, etc. The foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the appended claims.
[0062] While embodiments of the present disclosure have been illustrated and described, it will be clear that the disclosure is not limited to these embodiments only. Numerous modifications, changes, variations, substitutions, and equivalents will be apparent to those skilled in the art, without departing from the spirit and scope of the disclosure, as described in the claims.

ADVANTAGES OF INVENTION
[0063] The present disclosure provides a power factor controller to achieve a high power factor.
[0064] The present disclosure provides a power factor controller and method for enabling reactive power management using intelligent control of the reactive power.
[0065] The present disclosure provides a power factor controller and method for reactive power management that can control switching ON/OFF on capacitors and inductors that provide reactive power.
[0066] The present disclosure provides a reactive power based actual performance of the power distribution system/circuit.