Claims:We Claim:

1. An apparatus for filtering electrical glitches comprising of:

a Brushless DC (BLDC) Motor;

a hall sensor coupled with the BLDC motor, configured to detecting the electrical glitches, if any, and accordingly generating and transmitting signals for filtering the same; and

a motor controller configured to receive the transmitted signals and filter the electrical glitches so as to provide correct commutation to the BLDC motor.

2. The apparatus as claimed in claim 1, wherein said motor controller comprises of:

an input power means capable of receiving power from any external sources;

a microcontroller configured to receive power supply from the input power means and function as per the signal corresponding to accurate calculation of speed BLDC motor, transmitted by the hall sensor; and

an inverter configured to provide commutation to the BLDC motor, in cases, when there are no electrical glitches being detected by the hall sensor.

2. The apparatus for filtering glitches as claimed in claim 1, wherein said motor controller uses input signal generated by hall sensor as feedback received from the motor representing equivalent rotor position of the BLDC motor.

3. An apparatus for filtering glitches as claimed in claim 1, wherein said motor controller is having a power supply, Internal I/O’s sense and External I/O’s as an input to the micro-controller and thereby takes input from Hall sensor and output the pulse width modulation (PWM) to gate driver unit (inverter) MOSFET.

4. An apparatus for filtering glitches as claimed in claim 2, wherein said microcontroller treats the electrical glitch as a transition of hall sensor, wherein said transition enables the motor controller to calculate rotor position of the motor.

5. The apparatus for filtering glitches as claimed in claim 1, wherein said Hall sensors produces and sends signals as an input to the Motor Controller in the form of a ‘Square Wave’ of fifty percent duty cycle, indicating movement of the charge being carried through a conductor towards a magnetic attraction inside the BLDC Motor.

6. The apparatus for filtering glitches as claimed in any of the above claims, wherein the electrical glitches are detected corresponding to irregular repetitive frequency in the input produced by the Hall effect sensor.

7. An apparatus for filtering glitches as claimed in claim 1, wherein said BLDC motor comprises of stator armature and rotor, wherein the Hall sensor detects the position of the rotor and transform it into an electrical signal and employ the same to synchronize armature excitation with position of the rotor.

8. The apparatus for filtering glitches as claimed in claim 8, wherein stator is stationary and contains windings, wherein each winding is constructed with numerous interconnected coils placed in one or more coils slots.

9. A motor controller for filtering electrical glitches comprising:

an input power means capable of receiving power from any external sources;

a microcontroller configured to receive power supply from the input power means and function as per the signal transmitted by a hall sensor; and

an inverter configured to provide commutation to the BLDC motor, in cases, when there are no electrical glitches being detected by the hall sensor.

10. The motor controller as claimed in claim 9, wherein said motor controller is configured to coupled with a BLDC motor for filtering electrical glitches by acknowledging positions of rotor of the BLDC motor and mechanism to commutate the BLDC motor.
, Description:AN APPARATUS FOR FILTERING ELECTRICAL GLITCHES

FIELD OF THE INVENTION

[001] The present invention relates for detect irregularities/glitches in hall sensor. This invention is a unique to filter out the glitches for BLDC motor to ensure the right commutation is applied all the time and helps in accurate calculation of motor speed.

BACKGROUND OF THE INVENTION

[002] A brushless DC motor is a direct current motor that removes mechanical contact parts such as brushes and commutators, and instead uses an electronic rectifier to drive a rotor made of permanent magnets and a three-phase motor. Or it consists of a rotor which is equipped with a multiphase coil and rotates by the phase voltage of each coil.

[003] To provide a BLDC motor drive unit and control method therefore .SOLUTION: The control method for BLDC motor drive unit includes: a step for aligning motor rotors; a step for storing alignment information of the rotors; a step for determining whether or not the rotors are under an aligned state, and a step for realigning the motor rotors on the basis of the alignment information.

[004] To provide a control device for a BLDC motor that controls rotating-speed according to the number of poles in a replaced motor, while automatically sensing the motor replacement when a motor is replaced with the motor having the different number of poles, and its control method. ;SOLUTION: The control device for the BLDC motor 4 calculates a rotating speed by using rotating-speed calculation information set so as to be different from each other for each number of poles of the BLDC motor 4. The control device is composed by including a current sensor 6 which senses a load current of the BLDC motor 4; and a control unit 7 that senses the replacement with the motor having the different number of poles on the basis of changes in the sensed load current with respect to a reference load current, so as to change reference rotating-speed calculation information to the rotating-speed calculation information corresponding to the number of poles in the replaced motor.

[005] BLDC motor control method for calculating a rotational speed using rotational speed calculation information for rotational speed calculation that is set to be different depending on the number of poles of the BLDC motor. Calculating the rotational speed of the BLDC motor using reference rotational speed calculation information; compensating the speed so that the calculated rotational speed reaches a target rotational speed; and after compensating the speed, the BLDC Detecting a load current of the motor, and detecting a change to a BLDC motor having a different number of poles based on a change in the sensed load current with respect to a reference load current, and determining the number of poles of the replaced BLDC motor. And changing the reference rotational speed calculation information to rotational speed calculation information corresponding to the determined number of poles of the BLDC motor.
Below are the list of a few prior arts relevant to the present invention:
[006] US9774279B1 discloses a A system for controlling movement of an actuator includes an input power source that provides an input pulse width (PWM) signal; a motor driver that receives the PWM signal and provides a synthesized three-phase drive signal; a brushless direct current (BLDC) motor that receives the drive signal and operates in response to the received drive signal to reposition the actuator; and a controller that receives the PWM signal. The controller includes an amplitude detection module that detects the amplitude of the PWM signal, and a direction detection module that detects the polarity of the PWM signal.
[007] US20090640735 discloses An apparatus for controlling a BLDC motor includes a frequency controller configured to increase frequency of a drive signal that is applied to the motor to reach a first target speed at a relatively low speed region. The apparatus also includes a sensor less controller configured to observe location of a rotor of the motor at the low speed region, and provide a control signal to the motor by comparing a command speed with an estimated speed based on detection of a voltage and/or a current of the motor at a relatively high speed region. Further, the apparatus includes a control unit configured to select one of the frequency controller and the sensor less controller based on the speed of the motor.
[008] US19980178664 discloses A motor controller according to the present invention is so configured that time interval measuring means measures the time interval of a rotational position signal indicating the rotational position of a rotor based on said rotational position signal, correction coefficient storage means stores the correction coefficient indicating the inaccuracy of said rotational position signal, estimated rotational angle production means produces an estimated rotational angle providing an estimated value of the rotational angle by extrapolating the rotational angle based on said time interval and said correction coefficient, and command production means produces a current command or a voltage command based on said estimated rotational angle and outputs it to driving means for driving a motor.
[009] JP20130020923 discloses a drive unit for a brushless motor that makes a motor start with a simple method and in short time so as to obtain large torque when starting. SOLUTION: When a brushless motor is started, if a stopping position of a rotor is detected between a time t1 and a time t2, a start excitation pattern according to the stopping position of the rotor is input only for an initial energizing period Ts1. Then, when energization is stopped, a plurality of signals SL1, SL2, SL3, and SL4 are sequentially generated in an excitation switching timing signal, according to a rotational position of the rotor during free running. A rotor position is detected by using the second and subsequent signals SL2 to SL4 from among the signals SL1 to SL4, and control is migrated to normal energization switching control.
[010] CN201310415406 discloses a chip control device composed of a brushless DC motor and an electric actuator. A one-chip microcomputer control and drive circuit composed of one- chip microcomputer control and a BLDC drive circuit is connected with a rectification filter circuit, a function dial-up circuit, a control signal acquisition circuit and a feedback signal acquisition circuit, of a power supply, and is also connected with an over-current detection circuit and a feedback output circuit. The brushless DC motor is connected with the one-chip microcomputer control and drive circuit. According to the invention, great integration is achieved, so that the chip control device is advantaged by energy saving and high efficiency. The service life is relatively long, the cost is low, and the size is small. The chip control device is suitable for being used as a control device of electric performers.

[011] The above cited patents discloses a system for controlling a BLDC motor includes a frequency controller configured to increase frequency of a drive signal that is applied to the motor to reach a first target speed at a relatively low speed region there is no prior arts which is disclosing unique technique to filter out these glitches to ensure the right commutation is applied all the time. The main problems associated with above prior arts includes inefficient driving of the motor but also increases the chances of damage to the inverter circuit.
[012] While the methods and apparatuses disclosed in the prior arts have met their respective objectives and requirements, but they do not recognize the issues associated with a BLDC motor controller method treats the glitch as a transition of hall sensor. As a result, there is a need for filtering method to filter out these glitches to ensure the right commutation is applied all the time. This also helps in accurate calculation of motor speed. As well as to detect irregularities/ glitches in hall sensor input and to correct commutation sequence is thus applied to the motor correct computation of motor speed.

SUMMARY OF THE INVENTION
[013] The purpose of this invention is filtering of glitch required for BLDC motor applications where the motor is generating glitches. Hence, the invention is required by all BLDC motor control applications. Especially, it is needed in traction application for power above 900 W.
[014] In BLDC motor control application, the motor controller uses signal input (generated by HALL effect sensor) as a feedback from the motor representing the equivalent rotor position. Based on the rotor position the commutation is applied to make the motor rotate in expected direction. So, the commutation is the function of the HALL input signal. In addition, the frequency of HALL sensor is used to compute the motor speed. Ideally, all HALL effect sensors (3 in this case) generate the square wave of fifty percent duty cycle.
[015] However, in practical cases, BLDC motor HALL effect sensor generates a square wave that has repetitive irregularities (glitches). Now, if Motor controller doesn’t filter these glitches out then the commutation applied might be incorrect. This not only makes inefficient driving of the motor but also increases the chances of damage to the inverter circuit. Also, because of glitches, the apparent frequency of motor looks higher than the actual frequency leading to miscalculation of the speed.
[016] This invention is a unique method to filter out these glitches to ensure the right commutation is applied all the time. This also helps in accurate calculation of motor speed.
[017] In accordance with the present invention, one of the objectives is to provide a glitch detection system in Hall sensor input.
[018] Another objectives of the present invention is the application of correct commutation sequence to the motor
[019] The invention relates to a circuit for the detection of short voltage glitches in a supply voltage, comprising a comparator with a first input and a second input and an output for indicating a detected voltage glitch.

In accordance with one embodiment of the present invention, there is provided an apparatus for filtering electrical glitches comprising of a Brushless DC (BLDC) Motor, a hall sensor coupled with the BLDC motor, configured to detecting the electrical glitches, if any, and accordingly generating and transmitting signals for filtering the same, and a motor controller configured to receive the transmitted signals and filter the electrical glitches so as to provide correct commutation to the BLDC motor.

In accordance with the above embodiment of the present invention, wherein said motor controller comprises of an input power means capable of receiving power from any external sources, a microcontroller configured to receive power supply from the input power means and function as per the signal corresponding to accurate calculation of speed BLDC motor, transmitted by the hall sensor, and an inverter configured to provide commutation to the BLDC motor, in cases, when there are no electrical glitches being detected by the hall sensor.

In accordance with one embodiment of the present invention, there is provided an apparatus for filtering electrical glitches comprising of a Brushless DC (BLDC) Motor, a hall sensor coupled with the BLDC motor, configured to detecting the electrical glitches, if any, and accordingly generating and transmitting signals for filtering the same, and a motor controller configured to receive the transmitted signals and filter the electrical glitches so as to provide correct commutation to the BLDC motor, wherein said motor controller comprises of an input power means capable of receiving power from any external sources, a microcontroller configured to receive power supply from the input power means and function as per the signal corresponding to accurate calculation of speed BLDC motor, transmitted by the hall sensor, and an inverter configured to provide commutation to the BLDC motor, in cases, when there are no electrical glitches being detected by the hall sensor, wherein said motor controller uses input signal generated by hall sensor as feedback received from the motor representing equivalent rotor position of the BLDC motor.

In accordance with one embodiment of the present invention, there is provided an apparatus for filtering electrical glitches comprising of a Brushless DC (BLDC) Motor, a hall sensor coupled with the BLDC motor, configured to detecting the electrical glitches, if any, and accordingly generating and transmitting signals for filtering the same, and a motor controller configured to receive the transmitted signals and filter the electrical glitches so as to provide correct commutation to the BLDC motor, wherein said motor controller is having a power supply, Internal I/O’s sense and External I/O’s as an input to the micro-controller and said microcontroller produces outputs for HALL sensors and inverter depending on the detected electrical glitches.

In accordance with one embodiment of the present invention, there is provided an apparatus for filtering electrical glitches comprising of a Brushless DC (BLDC) Motor, a hall sensor coupled with the BLDC motor, configured to detecting the electrical glitches, if any, and accordingly generating and transmitting signals for filtering the same, and a motor controller configured to receive the transmitted signals and filter the electrical glitches so as to provide correct commutation to the BLDC motor, wherein said motor controller comprises of an input power means capable of receiving power from any external sources, a microcontroller configured to receive power supply from the input power means and function as per the signal corresponding to accurate calculation of speed BLDC motor, transmitted by the hall sensor, and an inverter configured to provide commutation to the BLDC motor, in cases, when there are no electrical glitches being detected by the hall sensor, wherein said motor controller uses input signal generated by hall sensor as feedback received from the motor representing equivalent rotor position of the BLDC motor, wherein said microcontroller treats the electrical glitch as a transition of hall sensor, wherein said transition enables the motor controller to calculate rotor position of the motor, wherein the electrical glitches are detected corresponding to irregular repetitive frequency in the input produced by the Hall effect sensor.

In accordance with one of the above embodiments of the present invention, wherein said Hall sensors produces and sends signals as an input to the Motor Controller in the form of a ‘Square Wave’ of fifty percent duty cycle, indicating movement of the charge being carried through a conductor towards a magnetic attraction inside the BLDC Motor.

In accordance with one of the above embodiments of the present invention, wherein said BLDC motor comprises of stator armature and rotor, wherein the Hall sensor detects the position of the rotor and transform it into an electrical signal and employ the same to synchronize armature excitation with position of the rotor, wherein stator is stationary and contains windings, wherein each winding is constructed with numerous interconnected coils placed in one or more coils slots.

In accordance with one embodiment of the present invention, there is provided a motor controller for filtering electrical glitches comprising an input power means capable of receiving power from any external sources, a microcontroller configured to receive power supply from the input power means and function as per the signal transmitted by a hall sensor, and an inverter configured to provide commutation to the BLDC motor, in cases, when there are no electrical glitches being detected by the hall sensor.

In accordance with just above embodiment of the present invention, wherein said motor controller is configured to coupled with a BLDC motor for filtering electrical glitches by acknowledging positions of rotor of the BLDC motor and mechanism to commutate the BLDC motor.
BRIEF DECSRIPTION OF THE DRAWINGS
[020] The following drawings illustrate by way of example and are included to provide further understanding of the invention for the purpose of illustrative discussion of the embodiments of the invention.
FIG. 1 depicts the Correct/expected hall sensor input

FIG. 2 depicts Glitches in hall input according to present invention.
Whereas, sometimes, traction BLDC motor produces hall sensor input as shown in figure 2.

FIG. 3 shows the expansion of glitch section for better view.

FIG. 4 shows a flowchart of the steps in an embodiment of the invention.

FIG. 5 shows the Block diagram of the Invention

DETAILED DESCRIPTION OF THE INVENTION

[021] A preferred embodiment of the present invention is now described with reference to the figures were like reference numbers indicate identical or functionally similar elements. With reference to FIGS. 1 through 5, this invention provides a method for filtering glitches for BLDC motor application for the purpose of application of correct commutation to the motor.

[022] Embodiments of the invention provide an efficient method for detecting abnormalities in data. In certain embodiments, time series data is received wherein each data point comprises values for a predetermined number of attributes. The data points are transformed into a simplified representation that tracks how each data point behaves with respect to the collection of data points over time. The transformed time series is then analyzed, data points exhibiting unusual or rare behavior are flagged, and an alarm is transmitted to alert responsible entities to undertake further studies, or to rectify any errors if the unusual or rare behavior is determined to derive from an error.

FIG. 1 shows the correct / expected hall sensor.
Position Sensor, which is usually a Hall Sensor (that works on the principle of Hall Effect) is generally used to detect the position of the rotor and transform it into an electrical signal. Most BLDC Motors use three Hall Sensors that are embedded into the stator to sense the rotor’s position.

The output of the Hall Sensor will be either HIGH or LOW depending on whether the North or South pole of the rotor passes near it. By combining the results from the three sensors, the exact sequence of energizing can be determined.

FIG. 2 shows Glitches in hall input.
BLDC motor HALL effect sensor generates a square wave that has repetitive irregularities (glitches). Now, if Motor controller doesn’t filter these glitches out then the commutation applied might be incorrect. This not only makes inefficient driving of the motor but also increases the chances of damage to the inverter circuit. Also, because of glitches, the apparent frequency of motor looks higher than the actual frequency leading to miscalculation of the speed.

FIG. 3 shows the expansion of glitch section for better view.
It is showing better view of glitches

Problems due to the glitches:
1. BLDC motor controller treats the glitch as a transition of hall sensor. Each transition of hall is used to calculate rotor position of the motor. Hence, glitches in hall measures wrong rotor position.
2. BLDC controller applies commutation to the motor based on the rotor position. If the rotor position is incorrect due to hall glitches then, the commutation applied will be wrong.
3. Wrong applied commutation can cause:
a. Huge phase current spikes
b. MOSFETs in the controller may damage
Wrong Torq position measurement also results in wrong motor speed calculation.

FIG. 4 shows a flowchart of the steps in an embodiment of the invention.

The hall glitch filter is implemented in the motor controller software as follows:
1. At start HALL (A, B, C) interrupts (both edges) are enabled
2. If HALL A interrupt is received (positive edge or negative edge), it is processed. And the glitch filter on HALL A is enabled (gstHall.u8GlitchFilter = D_GLITCH_FILTER_ON_A;).
3. Now, if there is successive edge on HALL A, it will be ignored because if ((gstHall.u8GlitchFilter & D_GLITCH_FILTER_ON_A) == 0) condition will be FALSE. So, the glitch is filtered.
4. Next interrupt can be of HALL B or HALL C.
5. The HALL B or C interrupt is serviced and the successive interrupt of the same HALL is disabled. At the same time the filter on another HALL is disabled.
6. Steps 2-5 should be executed in the loop.

It takes the Initialize HALL input signal as input capture with interrupt on both the rising and falling edges of the square waves. It clears the ‘HallGlitchFilter’ variable to disable the filter on all HALL signals. Next steps on this is to wait for another input capture interrupt.
Now, as the capture of interrupt is followed above, next step is applying the glitch filtering method accordingly as in ISR (Interrupt Service Routine).

The method when takes the captured interrupt it first starts to check which HALL signal is ISR. And process works this way – If the HALL A is under radar of interrupt service routine, then it goes to get tested whether it is under HallGlitchFilter, as now if HALL A is glitched, then it gets captured time to calculate HALL signal frequency. It starts to read all the HALL position and apply relevant commutation. Hence, it Enables HallGlitchFilter for HALL A and ‘HALLGlitchFilter are disables for HALL B and HALL C’.

But, if the HALL A not ISR, then flow checks goes to check the HALL B for checking whether HALL B is ISR or not. If it is under the radar of interrupt service routine, then it goes to get tested whether it is under HallGlitchFilter, as now if HALL B is glitched, then it gets captured time to calculate HALL signal frequency. It starts to read all the HALL position and apply relevant commutation. Hence, it Enables HallGlitchFilter for HALL B and ‘HALLGlitchFilter are disables for HALL A and HALL C’.

But, if the HALL B not ISR, then flow checks goes to check the HALL C for checking whether HALL C is ISR or not. If it is under the radar of interrupt service routine, then it goes to get tested whether it is under HallGlitchFilter, as now if HALL C is glitched, then it gets captured time to calculate HALL signal frequency. It starts to read all the HALL position and apply relevant commutation. Hence, it Enables HallGlitchFilter for HALL C and ‘HALLGlitchFilter are disables for HALL B and HALL C’.

FIG. 5 shows the Block Diagram for the apparatus for filtering electrical glitches.
To get deep dive now, BLDC Motor controller core source takes power supply, Internal I/O’s sense, and External I/O’s as an input to the Micro-controller which is node where HALL effect sensors creates as an output and generates an input signal for Motor. There is another output of micro-controller which is connected to Gate Driver Unit (Inverter) which main purpose is produce the appropriate current gate for power device. In our part this Gate Driver Unit (inverter) is MOSFET which gives greater efficiency while operating at lower voltages, it can also operate at lower power and draw no current. Therefore, the BLDC motor controller plays a major role for acknowledging the rotor position and mechanism to commutate the BLDC motor.

Now, these HALL effect sensors (3 in this invention) which are created as an input for BLDC Motor has sent as a ‘Square Wave’ of fifty percent duty cycle, this wave is a movement of the charge carries through conductor towards a magnetic attraction which is part of BLDC Motor. Here when waves form as input to motor it has its repetitive frequency which are irregulars, and thus called as glitches. Therefore, if BLDC Controller doesn’t filter these glitches then commutation applied will tends to be incorrect, which will cause multiple problems to the motor and performance.

BLDC motor controller methods treats the glitch as a transition of hall sensor. Each transition of hall is used to calculate rotor position of the motor. Hence, glitches in hall measures wrong rotor position.

BLDC controller applies commutation to the motor based on the rotor position. If the rotor position is incorrect due to hall glitches then, the commutation applied will be wrong.
Wrong applied commutation can cause: Huge phase current spikes, MOSFETs in the controller may damage. Wrong torq position measurement also results in wrong motor speed calculation.

While the invention is amenable to various modifications and alternative forms, some embodiments have been illustrated by way of example in the drawings and are described in detail above. The intention, however, is not to limit the invention by those examples and the invention is intended to cover all modifications, equivalents, and alternatives to the embodiments described in this specification.

The embodiments in the specification are described in a progressive manner and focus of description in each embodiment is the difference from other embodiments. For same or similar parts of each embodiment, reference may be made to each other.

It will be appreciated by those skilled in the art that the above description was in respect of preferred embodiments and that various alterations and modifications are possible within the broad scope of the appended claims without departing from the spirit of the invention with the necessary modifications.

Based on the description of disclosed embodiments, persons skilled in the art can implement or apply the present disclosure. Various modifications of the embodiments are apparent to persons skilled in the art, and general principles defined in the specification can be implemented in other embodiments without departing from the spirit or scope of the present disclosure. Therefore, the present disclosure is not limited to the embodiments in the specification but intends to cover the most extensive scope consistent with the principle and the novel features disclosed in the specification.