The present invention relates to controlling the RPM of a BLDC (Brush Less Direct Current motor) ceiling fan. More specifically, to regulate or operate the RPM of the BLDC ceiling fan by a regular in order to provide full comfort to the user.
BACKGROUND OF THE INVENTION
[002] Ceiling fans are generally induction motor driven or BLDC (Brushless Direct Current) motor driven. BLDC motor driven ceiling fans are nowadays preferred as they have multiple advantages like reduced power consumption, higher performance, controllability, increased life, better speed, torque characteristics, low noise generation, wider speed range and less maintenance. A BLDC motor driven ceiling fan includes a control unit to sense the rotor polarity and energies corresponding set of coils in the stator windings. The controller unit comprises an electronic controller incorporated in a printed circuit board (PCB), a sensor magnet and hall sensors.
[003] Conventionally, the Brushless motor type ceiling (BLDC) fan used a Hall effect sensor to detect the change of magnetic pole position of the rotor, and a filed effect transistor for output drive.
[004] Further, PWM (Pulse-width modulation) is commonly used in order to control the RPM (speed) of the brushless motor which involves the modulations of its duty cycle to control the amount of power sent to the load. Furthermore, PWM is used to control the supply of electrical power to the brushless motor, thereby controlling the speed of the brushless motor of the ceiling fan.

[005] Generally, a BLDC motor comes with FOC (Field orient control), which helps a motor to run at same RPM even if bus voltage is reduced.
[006] In case of regulator, it chops the supply voltage going to FAN input and that is why induction FAN speed is easily controlled with change in regulator position. But in case of BLDC ceiling FAN since the voltage will remain same even if the regulator position is changed, it is not straight forward to regulate the FAN speed.
[007] Therefore, in case of BLDC ceiling FAN the input impedance is sensed of at BLDC FAN input and based on the impedance measured, Speed input to the motor driver is changed.
[008] In IR remote control FAN, for press of each key a 16bit data is received through IR receiver and based on key identification PWM for the H-Bridge is controlled, which in general controls the BLDC motor speed. Problem
[009] Typically, induction FAN speed is known to be controlled using wall regulator whereas BLDC FAN speed is controlled using remote. The main problem with this is, it is not giving full comfort for the consumer. For an example if induction fan is installed at home and the user wants to change the speed at mid night, he/she has to come down to switch board and change the speed. At the same time if induction FAN is installed and if remote is misplaced, user cannot change the speed. Solution
[0010] To overcome with these problems, a solution is introduced which will enable the FAN to be controlled by using remote as well as wall regulator.
[0011] With the conventionally available control method, the BLDC fan has not been able to operate with the help of regulator.

[0012] Therefore, there is a need in the art to introduce a system which provides full comfort to the user by regulating the speed of the BLDC ceiling fan both by a remote or a regular.
OBJECTS OF THE INVENTION
[0013] The present invention has been accomplished under the circumstances in view. It is therefore the main object of the present invention to provide a brushless motor control circuit assembly that can also be controlled by the regulator.
[0014] An object of the present invention is to provide a BLDC motor driven ceiling fan which is simple in construction and which comprises a control unit that can control the RPM of the fan with regulator as well as Remote.
[0015] Another object of the present invention is to provide a BLDC motor driven ceiling fan which is convenient to use and provides multiple methods simultaneously to regulates the speed of the ceiling fan.
[0016] It is a further object of the present invention to provide full comfort to the user while regulating the RPM of a BLDC fan by remote or regulator.
[0017] Another object of this invention is to enable the user to change the RPM of the ceiling fan by remote or by regulator based on the latest command from the remote or regulator.
[0018] These and other objects and advantages of the invention will be apparent from the ensuing description when read in conjunction with the accompanying drawing.
[0019] Additional aspects, advantages, and features of the present invention are set forth in this specification, and in part will become apparent to those skilled in the art on examination of the following, or may be learned by practice of the invention. The inventions disclosed in this application are not limited to any particular set of or combination of aspects, advantages, and features. It is contemplated that various

combinations of the stated aspects, advantages, and features make up the inventions disclosed in this application.
SUMMARY OF THE INVENTION
[0020] The present invention generally relates to a BLDC (Brushless Direct Current motor) ceiling fan. More particularly, to regulate the RPM (Revolutions per minute) of the BLDC ceiling fan either by a remote or a regulator. The system comprises a power supply unit or a power supply mean to supply power to the motor of the BLDC ceiling fan and to other functional units/means. At least one transmitting mean to transmit a control command to the PCB of the BLDC ceiling fan, wherein, the transmitting mean can be a regulator or a remote. The system further comprises a sensing circuit for calculating the position of the regulator by identifying phase angle difference. The system also comprises a microcontroller to control the RPM of the ceiling fan based on the position of the regulator.
[0021] The working of BLDC fan comprises, when the power is supplied to the BLDC fan, the SMPS (switch-mode power supply) convert AC supply to DC supply, the microcontroller receives the input signal from at least one of the transmitting means and accordingly input signal microcontroller sends the signal to the inverter, then after inverter drives the BLDC Motor.
[0022] According to the present invention, a switched-mode power supply (SMPS) is an electronic power supply that is used to convert AC to DC and supply the DC to the BLDC ceiling fan. More specifically, the SMPS transfers power from a DC or AC source (often mains power, see AC adapter) to DC loads, such as a personal computer, a ceiling fan etc. while converting voltage and current characteristics. The SMPS is incorporated with a switching regulator to convert electrical power efficiently.

[0023] According to the present invention, at least one transmitting mean is used to send control command to the PCB fan in order to regulate and control the RPM of the ceiling fan wherein the at least one transmitting mean can be a regulator or a remote control.
[0024] According to the present invention, at least one transmitting mean is used to send control command to the PCB fan in order to regulate and control the RPM of the motor of the ceiling fan. The system further comprises a remote control designed for use with a ceiling fan which contains a transmitter. When operating properly, the remote transmitter is used to send a signal to a receiver in the ceiling fan that gives the fan simple instructions. Further, a memory unit is also configured in the microcontroller.
[0025] According to the present invention, the storage memory in the PCB is configured to store a predetermined array table and other necessary information. The predetermined array table includes the predetermined values for regulator and remote to operate the RPM of the ceiling fan.
[0026] According to the present invention, a Microcontroller is used for receiving the input data from an at least one transmitting mean control and give output data. In the present invention, the microcontroller is configured to control the RPM of the ceiling fan based on the regulator position. The microcontroller is further configured to identify whether a latest interest is coming from which transmitting mean.
[0027] According to the present invention, the sensing circuit is installed to calculate the position of the regulator by identifying phase angle difference. In an AC circuit, the voltage and the current are treated as vectors. The angle between these two vectors is the phase difference between the voltage and the current. The phase difference is related to the time difference between the voltage and current. For example, a phase difference of n radian leads to a time difference of T/2, where T is the time period.

Suppose the current leads the voltage by radian then the voltage reaches its maximum value after time, the current reaches its maximum value.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWING
[0028] The accompanying drawing, which is included to provide a further understanding of the invention and is incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention.
[0029] Features, elements, and aspects of the invention that are referenced in the drawing, equivalent, or similar features, elements, or aspects in accordance with one or more embodiments.
[0030] The below figure depicts an illustrative embodiment of the invention. This depicted embodiment is to be understood as illustrative of the invention and not as limiting in any way.
[0031] Various embodiments will hereinafter be described as accordance with the appended drawings, which are provided to illustrate, and not to limit the scope in any manner, wherein like designations denote similar elements, and in which:
[0032] Referring particularly to the drawing for illustration only and not limitation, there is illustrated:
[0033] Fig. 1. Illustrates a flow diagram as according to an embodiment of the present invention.
[0034] Fig. 2. Illustrates devising table as according to an embodiment of the present invention.

[0035] Fig. 3. Illustrates a Boost Circuit diagram as according to an embodiment of the present invention.
[0036] Fig. 4. Illustrates a circuit diagram as according to an embodiment of the present invention.
[0037] Fig. 5. Illustrates a circuit diagram as according to an embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0038] The following description of certian examples of the invention should bot be used to limit the scope of the present invention. Other examples, features, aspects, embodiments and advantages of the inventiuon will become apparent to those skilled in the art from the following description, which is by way of illustration, one of the best modes contemplated for carrying out the invention. As will be realized, the invention is capable if the other different and obvious aspects, all without departing from the invention. Accordingly, the drawings and descriptions should be regarded as illustrative in nature and not restrictive.
[0039] The present disclosure is best understood with reference to the detailed figures and description set forth herein. Various embodiments are discussed below with reference to the figures. However, those skilled in the art will readily appreciate that the detailed descriptions given herein with respect to the figures are simply for explanatory purposes as the methods and systems may extend beyond the described embodiments. For example, the teachings presented and the needs of a particular application may yield multiple alternate and suitable approaches to implement the functionality of any detail described herein. Therefore, any approach may extend beyond

the particular implementation choices in the following embodiments described and shown.
[0040] A speed command works for a BLDC motor-based ceiling fan consisting of 1) a wall-mounted power on/off switch or generally called as regulator; 2) an electronic controller consisting of a switched mode power supply, and a micro-controller in order to control the motor, wherein the micro-controller is configured to detect the position of the regulator in order to control and command the fan speed accordingly, wherein the microcontroller detects the speed commended by calculating the phase angle difference between the current and the voltage. Furthermore, the changes are interpreted by the microcontroller appropriately and the fan runs at the corresponding speed.
[0041] According to Fig. 1 of the present invention, the system starts with supplying power to the BLDC ceiling fan. If the regulator is turned off, the ceiling fan remains in switched-off mode, else the fan is started based on the position of the regulator. The system further comprises identifying whether the latest commend is coming from which transmitting mean i.e. either from remote controller or regulator. Based on the latest command from the transmitting mean, the RPM of the fan changes accordingly.
[0042] As according to the present invention, the RPM of the fan can be controller by simply turning the wall switch/regulator on the specified count i.e. 1, 2, 3, 4 or 5 stored in an array table with corresponding speed and phase angle difference ranges associated in the table, wherein to control the speed, the microcontroller is embedded in the motor body.
[0043] As according to other embodiment of the present invention, the microcontroller will monitor the bus voltage for a time period for predetermined time period every time when power is on.
[0044] Fig. 2 describes a division table for calculating circuit behaviour corresponding to different voltage and the speed, wherein as shown in

figure 2 of the present invention, the RPM is calculated on the basis of regulator position wherein the bus voltage is constant. Furthermore, as described in Fig. 2, in conventional method the speed of the fan is controlled by changing the bus voltage. Further, the bus voltage corresponds to the regulator steps which are predefined in the stored array table. Further, the constant voltage describes further in Fig. 3.
[0045] The circuit as shown in Fig. 3 illustrates a boost circuit that helps in maintaining constant voltage irrespective of the input voltage received in the range from 180 to 280 V. With the help of this circuit, even if regulator position is switched to 1st step, we will have 390V at motor BUS voltage because of which speed switching easily can be done.
[0046] The Boost APFC circuit controls the current by turning the MOSFET(QIOO) on and off by PWM input to gate, synchronizes the power supply voltage and phase, and brings the input current waveform closer to a sine wave.
[0047] When the MOSFET(QIOO) is in on state, the inductor(TRlOO) is being energized by the AC side of the circuit, and thus the inductor(TRlOO) current will be increasing. At the same time, diode (D100) becomes reverse biased and energy is provided to the load by the capacitor.
[0048] When the MOSFET(QIOO) is in off state, the inductor de-energizes (the current decreases) as it supplies energy to the load and for recharging the capacitor.
[0049] The cycling between the two states is done at a high frequency that is at least in the tens of kHz, but is often an order of magnitude (or even more) higher than that. The cycling back and forth between states is done rapidly and in a manner that both maintains a constant Bus voltage(VBUS) and controls the average inductor current (and subsequently the average AC current).

How do we change the speed?
[0050] The use of BM6248 IC in the circuit for motor control. This IC has dedicated pin(VSP) for speed input reference. Based on reference voltage at VSP pin, motor runs at different RPM.
[0051] This reference voltage is fed from microcontroller pin and this can be changed linearly. Maximum VSP voltage can fed is 4Vdc whereas minimum voltage is 1.2Vdc.
[0052] As shown in Fig. 4 of the present invention, Fig. 4 describes the circuit diagram for Inverter section to change the input commend and calculate the speed from the regulator and the speed from the remote.
How do we decide Speed for regulator?
[0053] Based on input voltage sensing and current sensing, the
capacitance value (i.e C= Ic/2fVc) is obtained. [0054] Here Ic = input current at rectifier
a. Vc = Input voltage at rectifier
b. F= input frequency (50Hhz)
[0055] Based on capacitance value, the regulator step position is identified and then the microcontroller generates VSP voltage for the required speed.
How do we decide speed for Remote?
[0056] Since irrespective of regulator position, the BUS voltage (390V) is same. Then whenever speed change command is given from remote, the VSP voltage will be switched from previous voltage to new required voltage and speed will change accordingly.

[0057] The Fig. 5 describes the voltage lowering by regulator. The operations of the circuit are as follows:
[0058] Remote operation is normal for input voltage of 140-280 V.
[0059] But regulator operation is normal in the range of 180-254 V
[0060] Below 180V & above 254V regulator speed steps is clubbed.
[0061] If further, in order to decrease Voltage operation below 180V, then transformer size need to increase which is not feasible in current form factor.
[0062] Altough a particular embodiment of the present invention has been described in details for the purpose of illustration, various modifications and enhancements may be made without departing from the spirit and scope of the present invention.
[0063] While the subject matter discussed herein is suspectible to various modifications and alternative constructions, certain illustrated embodiments thereof are shown in the drawings and have been described above in detail. It should be understood, howevevr, that there is no intention to limit the claims to the specific forms disclosed, but on the contrary, the intention is to cover all modifications, alternative constructions, and equivalents falling within the spirit and scope of the claims.
[0064] Some of the techniques described herein may be implemented by one or more computer programs executed by one or more processors residing, for example on a power tool. The computer programs include processor-executable instructions that are stored on a non-transitory tangible computer readable medium. The computer programs may also include stored data. Non-limiting examples of the non-transitory tangible computer readable medium are nonvolatile memory, magnetic storage, and optical storage.

[0065] Some portions of the above description present the techniques described herein in terms of algorithms and symbolic representations of operations on information. These algorithmic descriptions and representations are the means used by those skilled in the data processing arts to most effectively convey the substance of their work to others skilled in the art. These operations, while described functionally or logically, are understood to be implemented by computer programs. Furthermore, it has also proven convenient at times to refer to these arrangements of operations as modules or by functional names.
[0066] Unless specifically stated otherwise as apparent from the above discussion, it is appreciated that throughout the description, discussions utilizing terms such as "processing" or "computing" or "calculating" or "determining" or "displaying" or the like, refer to the action and processes of a computer system, or similar electronic computing device, that manipulates and transforms data represented as physical (electronic) quantities within the computer system memories or registers or other such information storage, transmission or display devices.
[0067] Certain aspects of the described techniques include process steps and instructions described herein in the form of an algorithm. It should be noted that the described process steps and instructions could be embodied in software, firmware or hardware, and when embodied in software, could be downloaded to reside on and be operated from different platforms used by real time network operating systems.
[0068] The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting. As used herein, the singular forms "a," "an," and "the" may be intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms "comprises," "comprising," "including," and "having," are inclusive and therefore specify the presence of stated features,

integers, steps, operations, elements, and/or components. The method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order discussed or illustrated, unless specifically identified as an order of performance.

WE CLAIM:

1. A system for controlling RPM of a BLDC ceiling fan by a regulator, the system
comprising:
a power supply mean is configured to supply power to the BLDC ceiling fan;
at least one transmitting mean is configured to transmits control commend to a
PCB of the BLDC ceiling fan;
a sensing circuit is configured to calculate a regulator position by identifying
phase angle difference; and
a microcontroller is configured to control the RPM of the ceiling fan based on the
regulator position.
2. The system as claimed in claim 1, wherein each of the transmitting means provided with a predefined array table.
3. The system as claimed in claim 1-2, wherein a storage memory is configured in the PCB to store the predetermined array table.
4. The system as claimed in claim 2, wherein the predetermined array table includes the predetermined values for regulator and remote to operate the RPM of the ceiling fan.
5. The system as claimed in claim 1, wherein the at least one transmitting means can be a regulator control or a remote control for the BLDC ceiling fan.
6. The system as claimed in claim 1, wherein the microcontroller is configured to identify whether a latest interest is coming from which transmitting mean.

7. A method for controlling RPM of a BLDC ceiling fan by a regulator, the method
comprising:
receiving, from a power supply mean, power to the BLDC fan;
transmitting, by a transmitting mean, a control commend to a PCB of the BLDC
ceiling fan;
calculating, by a sensing circuit, a position of the regulator by identifying phase
angle difference; and
controlling, by a microcontroller, the RPM of the ceiling fan based on the
regulator position.