WO2022226579A1 - Commutation électronique d'un moteur sans balais et sans capteur - Google Patents

Commutation électronique d'un moteur sans balais et sans capteur Download PDF

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Publication number
WO2022226579A1
WO2022226579A1 PCT/AU2022/050371 AU2022050371W WO2022226579A1 WO 2022226579 A1 WO2022226579 A1 WO 2022226579A1 AU 2022050371 W AU2022050371 W AU 2022050371W WO 2022226579 A1 WO2022226579 A1 WO 2022226579A1
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WIPO (PCT)
Prior art keywords
zero
motor
crossing point
commutation
open phase
Prior art date
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PCT/AU2022/050371
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English (en)
Inventor
Janislav Sega
Original Assignee
Janislav Sega
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Priority claimed from AU2021901242A external-priority patent/AU2021901242A0/en
Application filed by Janislav Sega filed Critical Janislav Sega
Publication of WO2022226579A1 publication Critical patent/WO2022226579A1/fr

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Classifications

    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
    • H02P6/00—Arrangements for controlling synchronous motors or other dynamo-electric motors using electronic commutation dependent on the rotor position; Electronic commutators therefor
    • H02P6/14—Electronic commutators
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
    • H02P6/00—Arrangements for controlling synchronous motors or other dynamo-electric motors using electronic commutation dependent on the rotor position; Electronic commutators therefor
    • H02P6/14—Electronic commutators
    • H02P6/16—Circuit arrangements for detecting position
    • H02P6/18—Circuit arrangements for detecting position without separate position detecting elements
    • H02P6/182—Circuit arrangements for detecting position without separate position detecting elements using back-emf in windings
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02K—DYNAMO-ELECTRIC MACHINES
    • H02K11/00—Structural association of dynamo-electric machines with electric components or with devices for shielding, monitoring or protection
    • H02K11/30—Structural association with control circuits or drive circuits
    • H02K11/33—Drive circuits, e.g. power electronics
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
    • H02P23/00—Arrangements or methods for the control of AC motors characterised by a control method other than vector control
    • H02P23/14—Estimation or adaptation of motor parameters, e.g. rotor time constant, flux, speed, current or voltage
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
    • H02P6/00—Arrangements for controlling synchronous motors or other dynamo-electric motors using electronic commutation dependent on the rotor position; Electronic commutators therefor
    • H02P6/14—Electronic commutators
    • H02P6/15—Controlling commutation time
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02K—DYNAMO-ELECTRIC MACHINES
    • H02K29/00—Motors or generators having non-mechanical commutating devices, e.g. discharge tubes or semiconductor devices
    • H02K29/06—Motors or generators having non-mechanical commutating devices, e.g. discharge tubes or semiconductor devices with position sensing devices
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
    • H02P2203/00—Indexing scheme relating to controlling arrangements characterised by the means for detecting the position of the rotor
    • H02P2203/03—Determination of the rotor position, e.g. initial rotor position, during standstill or low speed operation
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
    • H02P2203/00—Indexing scheme relating to controlling arrangements characterised by the means for detecting the position of the rotor
    • H02P2203/09—Motor speed determination based on the current and/or voltage without using a tachogenerator or a physical encoder
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
    • H02P25/00—Arrangements or methods for the control of AC motors characterised by the kind of AC motor or by structural details
    • H02P25/02—Arrangements or methods for the control of AC motors characterised by the kind of AC motor or by structural details characterised by the kind of motor
    • H02P25/022—Synchronous motors
    • H02P25/03—Synchronous motors with brushless excitation

Definitions

  • the present invention is directed to the area of control of electric brushless DC (BLDC) motors, and, in particular discloses a system and a method of electronic commutation of a sensorless BLDC motor in applications such as electric power tools.
  • BLDC electric brushless DC
  • BLDC Motors Brushless DC motors are used in a wide variety of market applications, such electric power tools, because they can offer increased energy efficiency and density, power output, compactness, operational reliability and life expectancy.
  • BLDC motors also known as permanent magnet synchronous motors (PMSM)
  • PMSM permanent magnet synchronous motors
  • phase winding configuration such as wye or delta
  • magnetic poles [1], [2], [3], [4]
  • Sensored BLDC Motor Control In today’s global markets, brushless motor applications are dominated by sensored BLDC motor control technologies [5], which utilize rotor position sensors inside the motors, such as Hall effect sensors or encoders. These sensors make it easy to electronically commutate and operate BLDC motors from start to high speeds. However, they increase the size and weight of the motors, and manufacturing costs due to additional components, circuitry and inter-wiring connections that are required. The rotor position sensors can also be subjected to operation at very high temperatures, electric and magnetic interference, and assembly placement errors that can lead to losses in energy efficiency and motor torque. Sensored BLDC motors are also prone to more electrical and mechanical failures which reduce system reliability and increase operating costs compared to alternate brushless motor control technologies that do not employ rotor position sensors.
  • Sensorless BLDC Motor Control Instead of using rotor position sensors, sensorless BLDC motor control techniques use only electrical measurements, such as motor phase voltages and currents, obtained directly from the motor in order to ascertain the rotor position during operation.
  • electrical measurements such as motor phase voltages and currents
  • Those skilled in the art of sensorless BLDC motor controller design are familiar with the inherent challenges of operating such motors at and near zero speeds [5], particularly in the presence of demanding dynamic loads, for example such as encountered in power tool fastening and drilling applications with cordless drill drivers. These issues often arise because of the technical difficulties associated with determining accurate rotor position information at zero and low speeds, which is important for robust electronic commutation of sensorless BLDC motors.
  • sensorless BLDC motor controller designs may use a hybrid approach, such as described in PCT Publication W02019/056072, entitled “System and Method for Controlling a Motor”, to the present applicant, incorporated here by cross reference, which can encompass one or more of the following key areas of controller operation: Initial rotor position detection (IRPD); Sensorless operation at zero and low motor speeds; Sensorless operation at high motor speeds.
  • IRPD Initial rotor position detection
  • Sensorless operation at zero and low motor speeds Sensorless operation at high motor speeds.
  • 6-Step Electronic Commutation The BLDC motor control systems described in previous sections generally employ the 6-step trapezoidal electronic commutation method because of its simplicity and effectiveness in controlling the torque and speed of a motor [7] In this commutation technique only two of the three BLDC motor phases conduct current at any time, while the third phase winding is left open. In sensorless BLDC motors the open phase windings are used to detect six consecutive commutation timing points separated by an angle of 60°, for example, as described in the “Low to High Speed Sensorless BLDCM Operation” embodiment of the aforementioned PCT Publication W02019/056072. The resultant 120° phase conduction angle motor driving scheme, however, does not generate the maximum possible torque in a motor.
  • the 6-step commutation Compared to other electronic commutation techniques, such as sinusoidal and FOC [7], the 6-step commutation also produces higher motor temperatures and increased motor torque ripple during operation, which can reduce the dynamic response when controlling the speed and torque of a motor in demanding applications, such as electric power tools.
  • a 12-step commutation scheme with increased phase conduction angle is implemented by activating the power transistors in a three-phase inverter so that current also flows through the third motor phase winding, which is normally left open in the 6-step trapezoidal commutation scheme, for an additional number of degrees during a commutation step.
  • US Patent US5463300, US Patent US4758768 and US Patent US9154062 disclose 12-step trapezoidal commutation methods for BLDC motors employing rotor position sensors, such as Hall effect sensors. However, these sensors increase manufacturing cost, equipment size, weight and reduce system efficiency and reliability of such BLDC motor control systems.
  • US Patent US6570353B2 discloses a 12-step BEMF voltage sensing commutation method of a sensorless BLDC motor with a fixed phase conduction angle of 150°.
  • US Patent Application US2020/0343840A1 discloses a 12-step commutation of a sensorless BLDC motor for power tools that can generate higher output motor torque with phase conduction angles greater than 120°, however, this method does not consider the problematic phase winding commutation demagnetization currents when determining the conduction angle.
  • US Patent US 8212504B2 discloses a method to improve stability of a 12-step commutation of a sensorless BLDC motor by reducing the conduction angle when the power supply voltage fluctuates. However this method also neglects the problematic open phase winding demagnetization currents that are present in the motor at the beginning of a new commutation step.
  • an electronic commutation of a sensorless brushless DC motor where the open phase voltages are used to measure the phase winding demagnetizing voltage of a BLDC motor so as to detect when the phase winding current is decaying to zero.
  • the open phase voltages are used to measure the rotor inherent and magnetic saturation (RIMS) saliency voltage of a BLDC motor.
  • RIMS rotor inherent and magnetic saturation
  • the open phase voltages are used to measure the back electro-motive force (BEMF) voltage of a BLDC motor.
  • BEMF back electro-motive force
  • an electronic commutation of a sensorless brushless DC motor which monitors the open phase winding demagnetization currents after a commutation state is changed in order to measure the corresponding open phase winding demagnetization time required to decay the open phase winding currents to zero.
  • the open phase winding demagnetization currents are measured using the open phase voltages, which are clipped by the internal power transistor diodes to the positive power supply voltage rail and the ground voltage rail after a commutation state is changed.
  • an electronic commutation of a sensorless brushless DC motor which measures the open phase voltages in order to detect the low to high and high to low zero-crossing points and to determine the time between consecutive zero-crossing points.
  • an electronic commutation of a sensorless brushless DC motor which determines the low to high and high to low open phase zero-crossing point detection voltage thresholds using CPFmaxR values that take into account the effects of rotor inherent and magnetic saliency of a BFDC motor present in open phase voltages, in order to control and improve the timing accuracy of the detected zero-crossing points.
  • the low to high and high to low open phase zero-crossing point detection voltage thresholds adjusted with CPFmaxR values are used to shift the detected zero-crossing points to the left. In some embodiments, the low to high and high to low open phase zero-crossing point detection voltage thresholds adjusted with CPFmaxR values are used to shift the detected zero-crossing points to the right.
  • an electronic commutation of a sensorless brushless DC motor which determines the open phase zero-crossing point detection window time using the measured open phase winding commutation demagnetization event time and the measured open phase zero-crossing point detection time, in order to obtain the corresponding open phase zero-crossing point detection window angle.
  • the measured open phase zero-crossing point detection window angle is maintained above a minimum reference open phase zero-crossing point detection window angle, by determining the open phase zero-crossing point detection window angle difference and using it as the input to a feedback controller in order to regulate the phase conduction angle so that the low to high and high to low open phase zero-crossing points are always detectable.
  • the open phase zero-crossing point detection window angle difference is used as the input to a feedback controller in order to stabilize the electronic commutation of a sensorless BLDC motor and to control the phase conduction angle between a set minimum and maximum phase conduction angle values so as to maximize the output phase conduction angle and the generated motor torque under all motor loading and operating conditions.
  • an electronic commutation of a sensorless brushless DC motor which monitors the behaviour of the measured open phase zero-crossing voltages during zero-crossing point detection, by comparing the said open phase voltages during the low to high and high to low zero-crossing point detection intervals against a set of voltage references calculated from the power supply voltage, in order to prevent zero-crossing point run aways and commutation timing errors.
  • zero-crossing point run-away limiters are used to limit the maximum phase conduction angle in order to prevent commutation timing errors and improve the stability of commutation of a sensorless brushless DC motor.
  • a soft zero-crossing point run-away limiter is used, which decreases the phase conduction angle to a minimum conduction angle value at a controlled rate when the open phase BEMF voltage exceeds a set of voltage references during zero-crossing point detection.
  • a hard zero-crossing point run-away limiter is used, which decreases the phase conduction angle to a minimum conduction angle value immediately when the open phase BEMF voltage exceeds a set of voltage references during zero-crossing point detection.
  • Fig. 1 illustrates a system block diagram of a disclosed method of electronic commutation of a sensorless BLDC motor.
  • Fig. 2 illustrates a sensorless BFDC motor controller circuitry (prior art).
  • FIG. 3 illustrates an operation flow diagram of a sensorless BFDC motor controller (prior art).
  • Fig. 4 illustrates a low to high (F H) and a high to low (H F) commutation point detection employing voltage thresholds calculated with CPFmax measurements that account for effects of rotor inherent and magnetic saturation (RIMS) saliency in a sensorless BFDC motor (prior art).
  • F H low to high
  • H F high to low
  • Fig. 5 illustrates a practical example of measured motor phase voltages during operation of disclosed electronic commutation of a sensorless BFDC motor in a power tool at high load, showing commutation timing intervals consisting of a zero-crossing point interval (TZCP), an open phase winding commutation demagnetization event (CDE), an open phase zero-crossing point detection window angle (to) and a resultant phase conduction angle (a).
  • TZCP zero-crossing point interval
  • CDE open phase winding commutation demagnetization event
  • a resultant phase conduction angle
  • Fig. 6 illustrates a practical example of measured motor phase voltages during operation of disclosed electronic commutation of a sensorless BFDC motor in a power tool operating at a high speed (-50KRPM electrical cycle) and a high phase conduction angle (-162°), with disclosed zero-crossing point “run-away” limiter functionality disabled, showing an increasing voltage difference (dV) between consecutive open phase BEMF voltage and half of the supply voltage (Vs/2) measurements, leading to a missed zero-crossing point detection and ultimately a motor commutation error.
  • dV voltage difference
  • Fig. 7 illustrates a practical example of measured motor phase voltages during an initialization operation of disclosed electronic commutation of a sensorless BFDC motor in a power tool, showing three zero-crossing point detection initialization cycles when commutation operation changes from 6-step to 12-step with conduction angle (a) initialized to a minimum value (a mm ).
  • Fig. 8 illustrates a waveform and timing diagram of disclosed 12-step electronic commutation of a sensorless BLDC motor, showing motor phase voltages, phase currents, three-phase PWM transistor gate driver outputs and important commutation logic signals.
  • Fig. 9 illustrates different modes of phase conduction angle regulation of disclosed electronic commutation of a sensorless BLDC motor, showing a zero-crossing point detection initialization mode, a zero-crossing point detection window feedback controller operation mode, and a soft and a hard zero crossing point run-away limiter operation mode, developed to improve performance and stability of electronic commutation operation with high conduction angles (a).
  • Fig. 10 illustrates a top-level operation flow diagram of a disclosed method of electronic commutation of a sensorless BLDC motor.
  • Fig. 11 illustrates a sub-level operation flow diagram of disclosed method of electronic commutation of a sensorless BLDC motor, showing a zero-crossing point detection unit operation.
  • Fig. 12 illustrates a sub-level operation flow diagram of disclosed method of electronic commutation of a sensorless BLDC motor, showing a commutation demagnetization event (CDE) detection unit operation.
  • CDE commutation demagnetization event
  • Fig. 13 illustrates a sub-level operation flow diagram of disclosed method of electronic commutation of a sensorless BLDC motor, showing a zero -crossing point detection window feedback controller unit operation.
  • Fig. 14 illustrates a sub-level operation flow diagram of disclosed method of electronic commutation of a sensorless BLDC motor, showing a zero-crossing point run-away soft limiter unit operation.
  • Fig. 15 illustrates a sub-level operation flow diagram of disclosed method of electronic commutation of a sensorless BLDC motor, showing a zero-crossing point run-away hard limiter unit operation.
  • Fig. 16 illustrates a sub-level operation flow diagram of disclosed method of electronic commutation of a sensorless BLDC motor, showing a zero-crossing point detection initialization unit operation.
  • the embodiments are directed to the area of electronic commutation of electric brushless DC (BLDC) motors, with a particular focus on the sensorless BLDC motors and control systems in applications, such as electric power tools.
  • the application and technology relate generally to the challenges of creating an effective and a stable and robust electronic commutation of sensorless BLDC motors with increased motor torque.
  • a set of challenges for electronic commutation of sensorless BLDC motors are apparent, which translate across a large set of applications and realizations, these are: Stability and robustness of electronic commutation of sensorless BLDC motors with high phase conduction angles; Stability and robustness of electronic commutation of sensorless BLDC motors in the presence of low motor speeds, high motor loads and high open phase winding demagnetization currents; Stability and robustness of electronic commutation of sensorless BLDC motors in the presence of high motor speeds and rapid accelerations and decelerations; Electronic commutation of sensorless BLDC motors in the presence of rotor inherent and magnetic saturation (RIMS) saliency effects in open phase voltages of a BLDC motor; Electronic commutation of a broad range of sensorless BLDC motors (IPM, salient and non-salient pole, wye and delta winding); Electronic commutation of sensorless BLDC motors without any rotor position sensors, such as Hall effect sensors
  • the embodiments provide an electronic commutation of sensorless BLDC motors that have improved stability, performance, operational behaviour and greater flexibility across one or more of these areas of challenge.
  • the disclosure of the embodiments is applicable to a wide area, and more broadly applicable to the application of sensorless BLDC motors across applications, including and not limited to power tools, mobility, locomotion, robotics, automation and control, automotive, medical, consumer, hobby, etc.
  • a general primer of the breadth and applicability of the areas of interest and application of BLDC motors can be found in [1], [2], [3], [4]
  • the embodiments provide an electronic commutation of a sensorless BLDC motor which uses a multiphase electric BLDC motor without any rotor position sensors.
  • the embodiments provide an electronic commutation of a sensorless BLDC motor where the open phase voltages are used to measure the phase winding demagnetizing voltage of a BLDC motor so as to detect when the phase winding current is decaying to zero.
  • the embodiments provide an electronic commutation of a sensorless BLDC motor where the open phase voltages are used to measure the rotor inherent and magnetic saturation (RIMS) saliency voltage of a BLDC motor. [0061] The embodiments provide an electronic commutation of a sensorless BLDC motor where the open phase voltages are used to measure the back electro -motive force (BEMF) voltage of a BLDC motor.
  • RIMS rotor inherent and magnetic saturation
  • the embodiments provide an electronic commutation of a sensorless BLDC motor which monitors the open phase winding demagnetization currents after a commutation state is changed, ie. detects a commutation demagnetization event (CDE), in order to measure the corresponding open phase winding commutation demagnetization event time (TCDE) required to decay the phase winding currents to zero.
  • CDE commutation demagnetization event
  • TCDE open phase winding commutation demagnetization event time
  • the embodiments provide an electronic commutation of a sensorless BLDC motor which measures the open phase winding demagnetization currents using the open phase voltages, which are clipped by the internal power transistor diodes to the power supply positive voltage rail and the ground voltage rail after a commutation state is changed.
  • the embodiments provide an electronic commutation of a sensorless BLDC motor which measures the open phase voltages in order to detect the low to high (L H) and high to low (H L) zero-crossing points and determine the time between consecutive zero-crossing points (TZCP).
  • L H low to high
  • H L high to low
  • TZCP time between consecutive zero-crossing points
  • the embodiments provide an electronic commutation of a sensorless BLDC motor which detects the zero-crossing point time (TZCP) using the low to high (L H) and high to low (H L) zero- crossing point detection voltage thresholds adjusted with CPFmaxR values that take into account the effects of rotor inherent and magnetic (RIMS) saliency of a BLDC motor present in the open phase voltages, which can shift the measured zero-crossing points away from the true zero-crossing points, in order to control and improve the timing accuracy of the detected zero-crossing points.
  • TZCP zero-crossing point time
  • L H low to high
  • H L high to low
  • RIMS rotor inherent and magnetic
  • the embodiments provide an electronic commutation of a sensorless BLDC motor which adjusts the low to high and high to low open phase zero-crossing point detection voltage thresholds using CPFmaxR values in order to shift the detected zero-crossing points to the left.
  • the embodiments provide an electronic commutation of a sensorless BLDC motor which adjusts the low to high and high to low open phase zero-crossing point detection voltage thresholds using CPFmaxR values in order to shift the detected zero-crossing points to the right.
  • the embodiments provide an electronic commutation of a sensorless BLDC motor which determines the open phase zero-crossing point detection window time (Tco) using the measured open phase winding commutation demagnetization event time (TCDE) and the measured zero-crossing point detection time (TZCP), in order to obtain the corresponding open phase zero-crossing point detection window angle (to).
  • Tco open phase zero-crossing point detection window time
  • TCDE measured open phase winding commutation demagnetization event time
  • TZCP measured zero-crossing point detection time
  • the embodiments provide an electronic commutation of a sensorless BLDC motor which ensures that the open phase zero-crossing point detection window angle (to) is always above a minimum reference zero-crossing point detection window angle (comin), by determining the zero-crossing point detection window angle difference (Dw) which is used as the input to a feedback controller in order to regulate the phase conduction angle (a) so that the low to high (L H) and high to low (H L) open phase zero-crossing points are always detectable during a commutation step.
  • Dw zero-crossing point detection window angle difference
  • the embodiments provide an electronic commutation of a sensorless BLDC motor which uses the open phase zero-crossing point detection window angle difference (Dw) as the input to a feedback controller, consisting of a PID controller and a magnitude saturator, in order to stabilize the electronic commutation of a sensorless BLDC motor and to control the phase conduction angle (a) in a range between a min and oi max so as to maximize the generated motor torque under all motor loading and operating conditions, for example, such as, high and low motor loads, high and low open phase winding demagnetization currents and corresponding long and short open phase winding demagnetization times, high and low motor speeds, and rapid motor accelerations and decelerations, as commonly encountered in applications such as electric power tools.
  • Dw open phase zero-crossing point detection window angle difference
  • a feedback controller consisting of a PID controller and a magnitude saturator
  • the embodiments provide an electronic commutation of a sensorless BLDC motor which monitors the behaviour of the measured open phase zero-crossing phase voltages during zero-crossing point detection, by comparing the open phase voltages during the low to high (L H) and high to low (H L) zero-crossing point detection intervals against a set of voltage references calculated from the power supply voltage (Vs), in order to prevent zero-crossing point run-away conditions and resultant 12- step commutation timing errors during high motor speeds and rapid motor accelerations and decelerations.
  • Vs power supply voltage
  • the embodiments provide an electronic commutation of a sensorless BLDC motor which uses zero-crossing point run-away limiters to limit the maximum phase conduction angle (a) in order to improve stability and prevent commutation timing errors by: Decreasing the phase conduction angle (a) to a minimum conduction angle (a m in) at a controlled rate when the zero-crossing open phase voltage exceeds a set of voltage references, ie. a “soft” limiter; and, or Decreasing the phase conduction angle (a) to a minimum conduction angle (a min ) immediately when the zero-crossing open phase voltage exceeds a set of voltage references, ie. a “hard” limiter.
  • it is instructive to introduce some sensorless BLDC motor controller background information.
  • the basic equivalent circuit for the control of the sensorless BLDC motor such as used by the disclosed electronic commutation, is illustrated 20 in Fig. 2.
  • This sensorless BLDC motor control circuit is described in greater detail in the aforementioned PCT Publication W02019/056072.
  • the sensorless BLDC motor control system includes:
  • a sensorless BLDC motor switching control circuit 23 also commonly known as an inverter, consisting of plurality of semiconductor power transistor switches (A_L, A H, B_L, B_H, C L, C_H) 23 such as MOSFETs or IGBTs to control the pulse width modulated (PWM) phase winding currents in a synchronized manner with the rotor position, and includes freewheeling semiconductor diodes e.g. 24 to conduct PWM off-time switching inductive currents.
  • PWM pulse width modulated
  • a power transistor gate control circuit 27 consisting of plurality of gate drivers (A_L, A_H, B_L, B_H, C L, C_H) to optimally control the power transistors during switching operation;
  • An analog to digital converter (ADC) circuit 26 converting at high speed, a plurality of analog voltage measurements (Va, Vb, Vc) 29, which can include voltage resistor divider networks to reduce the sampled analog voltages to an acceptable level for measurement with an ADC and capacitors to reduce measured analog voltage bandwidth and fdter out electrical noise .
  • ADC analog to digital converter
  • a microcontroller 28 which provides various functionalities.
  • the microcontroller may comprise peripherals such as an integrated high speed ADC circuit, volatile memory such as DRAM, and non-volatile memory such as PROM, EPROM, EEPROM, FLASH, MRAM, PCRAM, and other functionalities such as timers, user input and output interfaces, communication ports, comparator circuits, and operational amplifier circuits etc.
  • An electrical voltage source such as a battery or a transformer or a switching power supply is also provided (not shown).
  • the power supply voltage (Vs) can be measured: Indirectly via the analog voltage measurements (Va, Vb, Vc) 29 and an ADC circuit 26 when the corresponding high-side power transistors (A H, B_H, C_H) 23 are switched on to the power supply voltage rail (Vs); or Directly with an analog input voltage measurement connected directly to the voltage source rail (Vs) , which can include voltage resistor divider networks to reduce the sampled analog voltages to an acceptable level for measurement with an ADC and capacitors to reduce measured analog voltage bandwidth and fdter out electrical noise (not shown).
  • the sensorless BLDC motor controller operation block diagram 1 such as used by the disclosed electronic commutation method is illustrated in Fig. 3. This sensorless BLDC motor controller operation is described in greater detail in the aforementioned PCT publication WO2019/056072.
  • the sensorless BLDC motor controller operation block diagram includes:
  • An initial rotor position detection (IRPD) operation which is used to detect the starting rotor position of a sensorless BLDC motor at standstill or in motion, including during reversed rotor momentum rotation, without using rotor position sensors such as Hall effect sensor or encoders.
  • IRPD initial rotor position detection
  • a zero to high speed sensorless BLDC motor control operation which may include a hybrid sensorless BLDC motor control approach as illustrated in Fig. 3, consisting of a zero to high speed sensorless BLDC motor operation, and a low to high speed sensorless BLDC motor operation, for example, during which the disclosed electronic commutation method is applied, designed to successfully drive a broader range of BLDC motors from zero speed to high speeds under all motor loading conditions, including during reversed rotor momentum motor operation conditions, without using rotor position sensors such as Hall effect sensor or encoders.
  • This section discloses the present embodiments of the system and method of electronic commutation of a sensorless BLDC motor developed for motor control applications, such as electric power tools.
  • FIG. 1 The system block diagram 10 of the disclosed electronic commutation of a sensorless BLDC motor is illustrated in Fig. 1.
  • the key system components of the developed 12-step commutation scheme include: A voltage sensing based sensorless BLDC motor controller, such as described in the “Low to High Speed Sensorless BLDCM Operation” embodiment of the aforementioned PCT Publication W02019/056072, consisting of a hardware circuitry 20, such as illustrated in Fig. 2, and an operational flow diagram 1, such as illustrated in Fig. 3, that integrates the disclosed electronic commutation of a sensorless BLDC motor with a method of operation as illustrated in the top-level operation flow diagram 30 in Fig.
  • a motor phase voltage detection circuitry 100 which is used to measure the motor phase and BEMF voltages (Va, Vb, Vc) 29, and the power supply voltage (Vs) 16, for example using an ADC circuit 26 integrated inside a microcontroller 28 as illustrated in Fig.
  • An open phase voltage zero-crossing point detection unit 110 A motor commutation demagnetization event (CDE) detection unit 120;
  • An open phase voltage zero crossing point detection window feedback controller 130 unit consisting of a PID controller 133 and a magnitude saturator 134;
  • a BEMF voltage zero-crossing point run-away limiter 140 unit consisting of a soft 140a and a hard 140b phase conduction angle limiter;
  • a three-phase PWM generator 170 implemented inside a microcontroller 28 that drives the power transistors using a gate driver 27, such as illustrated in Fig.
  • a three-phase inverter 23 consisting of plurality of power transistors (A_L, A H, B_L, B_H, C L, C_H) that drive the three-phase BLDC motor 21, such as illustrated in Fig. 2.
  • the present embodiments use information about the motor phase winding demagnetization currents and the behaviour of the BEMF voltage measurements during zero-crossing point detection, for example, a zero crossing point run-away event, such as shown in Fig. 6, to provide a distinct advantage and obtain improved stability, performance and operational behaviour with 12-step commutated sensorless BLDC motors, and to obtain greater possibility when operating these motors with high phase conduction angles (eg. a >140°) under different loading conditions, such as, high loads, low speeds, high speeds, rapid accelerations and decelerations, commonly encountered in electric power tool applications.
  • high phase conduction angles eg. a >140°
  • the present embodiments take into account the effects of rotor inherent and magnetic (RIMS) saliency [12] of BLDC motors, which can shift the measured zero-crossing points away from the true zero-crossing points, to control and improve the timing accuracy of the detected zero-crossing points.
  • RIMS rotor inherent and magnetic
  • the present embodiments offer improved performance, operational behaviour and greater possibility in achieving a reliable and robust 12-step commutation of sensorless BLDC motors across a broader range of phase conduction angles (eg. 120° ⁇ a ⁇ 165°).
  • the present embodiments can attain increased motor torque, faster applications speeds, longer operation run-times and lower motor temperatures when employing the disclosed 12-step trapezoidal commutation method with an increased conduction angle compared to the standard 6-step commutation, which is important in applications such as electric power tools.
  • the operation of the disclosed electronic commutation of a sensorless BLDC motor starts by measuring the motor phase voltages 100, which includes measuring the open phase voltage of the third phase winding when it is not activated.
  • These open phase voltages can, for example, be used to measure: The back electro -motive force (BEMF) voltages of a BLDC motor; or the zero-crossing point detection voltages affected by rotor inherent and magnetic saturation (RIMS) saliency in a BLDC motor, for example, as illustrated in Fig.
  • BEMF back electro -motive force
  • RIMS rotor inherent and magnetic saturation
  • the measured phase voltages (Va, Vb, Vc) 29 are used by the zero-crossing point detection unit 110 to obtain the zero-crossing points (TZCP) 111, and by the commutation demagnetization event (CDE) detection unit 120 to measure the time to decay the open phase winding demagnetization currents to zero (TCDE) 121.
  • the measured TCDE 121 value varies with the motor speed and load, which in general results in a longer time with high motor loads and low speeds, and a shorter time with low motor loads and high speeds.
  • the measured TZCP 111 and TCDE 121 are then used to calculate the open phase zero-crossing point detection window time (Tco) 139 and the corresponding zero-crossing point detection window angle (to) 131, which is used by a feedback controller 130 to calculate the optimal conduction angle (a) 14.
  • This PID feedback controller 130 ensures that the zero-crossing point detection window angle (to) 131 is kept above the minimum window angle (comin) 11, set by the user, by reducing the conduction angle (a) 14 if w 131 ⁇ oj mm 11.
  • the feedback controller 130 also maximizes the conduction angle (a) 14 value, which can, for example, be set in the range between a min 12 and a max 13 (eg. 120° ⁇ a ⁇ 165°) during operation, as required by the application.
  • the open phase BEMF voltages are monitored to prevent missed zero-crossing point detections and commutation timing errors during operation, using the zero-crossing point run-away limiter 140.
  • a minimum value eg. a min 12
  • Two phase conduction angle limiters are implemented: a soft conduction angle limiter 140a which reduces the conduction angle (a) 15 at a controlled rate when the open phase BEMF voltages exceed the set supply voltage thresholds 142 or 143; and a hard conduction angle limiter 140b, which limits the conduction angle (a) 15 to a min 12 instantaneously when the open phase BEMF voltages exceed the set supply voltage thresholds 148 or 149.
  • a soft conduction angle limiter 140a which reduces the conduction angle (a) 15 at a controlled rate when the open phase BEMF voltages exceed the set supply voltage thresholds 142 or 143
  • a hard conduction angle limiter 140b which limits the conduction angle (a) 15 to a min 12 instantaneously when the open phase BEMF voltages exceed the set supply voltage thresholds 148 or 149.
  • FIG. 9 illustrates the different zero-crossing point detection window feedback controller and run-away limiter modes of operation developed to regulate the conduction angle (a) 14 15 during commutation of a sensorless BLDC motor.
  • the output conduction angle (a) 15 is then finally used to calculate the commutation timing point (TCP) 160, which in conjunction with the measured zero-crossing point detection time (TZCP) 111 is used by the three-phase PWM output generator 170 to drive the power transistors of the three-phase inverter 23 with conduction angles >120°.
  • TCP commutation timing point
  • TZCP measured zero-crossing point detection time
  • Fig. 1 is used to measure the motor phase voltages (Va, Vb, Vc) 29, and indirectly the power supply voltage (Vs) 16, for example, when the corresponding high-side power transistors (A H, B_H, C_H) 23 are switched-on to the power supply voltage rail (Vs) 16.
  • the open phase voltages 29 measured when the third phase winding is not activated can, for example, be used to measure: The back electro -motive force (BEMF) voltages of a BLDC motor; or the zero-crossing point detection voltages affected by rotor inherent and magnetic saturation (RIMS) saliency in a BLDC motor, for example, as illustrated in Fig.
  • BEMF back electro -motive force
  • RIMS rotor inherent and magnetic saturation
  • the open phase winding demagnetization voltages which are clipped, by the internal power transistor diodes, the open phase voltages to the positive supply voltage rail 53 or the ground voltage rail 54 when the open phase winding current is decaying to zero, for example, as shown in Fig. 5 and Fig. 8.
  • These voltages are measured at a regular time interval (eg. every few microseconds), for example, using an ADC circuit 26 and a microcontroller 28, as shown in Fig. 2, which are integrated into a sensorless BLDC motor controller, such as described in the “Low to High Speed Sensorless BLDCM Operation” embodiment of the aforementioned PCT Publication W02019/056072.
  • the zero-crossing point detection unit 110 illustrated in Fig. detects when the open phase voltages 29 cross half of the power supply voltage rail (Vs/2), during a low to high (L H) 51 and a high to low (H L) 52 zero-crossing point detection, for example, as illustrated in the waveform and timing diagram in Fig. 8 and shown in the practical example in Fig. 5.
  • the disclosed zero-crossing point detection 110 method extends on the commutation point detection method described in the “Low to High Speed Sensorless BLDCM Operation” embodiment of the aforementioned PCT Publication W02019/056072 by taking into account the rotor inherent and magnetic saturation (RIMS) saliency effects [12], for example, such as encountered in high saliency BLDC interior permanent magnet (IPM) motors used in power tools.
  • RIMS rotor inherent and magnetic saturation
  • IPM interior permanent magnet
  • the measured open phase winding voltages affected by RIMS saliency use the CPFmax value to correct the timing of the low to high (L H) 51 and high to low (H L) 52 zero-crossing point detection voltage thresholds during the 12-step commutation of sensorless BLDC motors, as illustrated in Fig. 4.
  • L H low to high
  • H L high to low
  • a low to high zero-crossing point is detected when the phase voltage > Vs . ( 1 ⁇ 2+N .
  • C P Fm ax R C P Fm ax R 113, and a high to low zero-crossing point is detected when the phase voltage ⁇ Vs. (1 ⁇ 2-N. CPFmaxR) 114, as illustrated in the operation flow diagram 110 in Fig. 11.
  • the supply voltage independent ratio value CPFmaxR ie. CPFmax/Vs
  • CPFmaxR 0.1 - 1.0
  • This method can also be used to increase (eg. N ⁇ 0) or decrease (eg.
  • N 0
  • the phase conduction angle (a) 15
  • Vs/2 the power supply voltage rail
  • the time between two consecutive zero-crossing points (TZCP) 111 is read from a timer 55, for example implemented inside a microcontroller 28.
  • the zero-crossing point time TZCP 111 and the commutation demagnetization event time (TCDE) 121 which is measured by the CDE unit 120, are used to calculate the zero-crossing point detection window time (Tco) 139 and the next commutation point time (TCP) 160.
  • the zero-crossing point detection 110 operation is performed during the top-level electronic commutation operation 30 illustrated in the flow diagram in Fig. 10, and during the zero crossing point detection initialization 150 illustrated in the operation flow diagram in Fig. 16.
  • the initialization operation 150 begins by setting the phase conduction angle (a) 15 to the minimum possible value a mm 12, as set by the application, and then performing a number of initialization cycles (N) 153 during which consecutive zero-crossing points 110 are detected using the 6-step commutation method, as shown in the exemplary Fig. 7. This ensures that the reference commutation time between two consecutive zero-crossing points (TZCP) 111 has been measured and is valid as soon as the 12-step commutation method is enabled.
  • the commutation point (TCP) 160 which sets the duration when the power transistors 23 are driven with conduction angles >120°, is also initialized during this phase:
  • ZCP zero-crossing point
  • This method results in more stable and reliable commutation of sensorless BLDC motors.
  • this operation is performed by the commutation demagnetization event (CDE) detection unit 120, illustrated in the system block diagram in Fig. 1 and in the operation flow diagram in Fig. 12.
  • CDE commutation demagnetization event
  • a longer demagnetization time (TCDE) 121 results when a motor is operated at high loads and slow speeds, and a shorter demagnetization time results when a motor is operated at low loads and high speeds.
  • TCDE demagnetization time
  • a shorter demagnetization time results when a motor is operated at low loads and high speeds.
  • a commutation demagnetization event (CDE) 120 can occupy >1/3 of the total time interval between two consecutive commutation points (TZCP) 111. This reduces the open phase zero-crossing point detection window time (Tco) 139 and the corresponding zero-crossing point detection window angle (to) 131, and for example, as shown in Fig.
  • phase winding demagnetization currents generate open phase inductive voltage spikes, which are clipped by the internal power transistor diodes 24 to the positive power supply voltage 53 and the ground voltage 54 rails after a commutation state is changed, as shown in exemplary Fig. 5, and illustrated in the waveform and timing diagram in Fig. 8.
  • the commutation demagnetization event (CDE) unit 120 detects these open phase winding demagnetization voltage spikes 53, 54 using the open phase voltages (Va, Vb, Vc) 29 measured by the phase voltage detection unit 100. This operation is illustrated in the operation flow diagram in Fig. 12.
  • NCDEHL 0.1 - 0.5
  • phase winding demagnetization time (TC DE ) 121 is read from a timer 55, for example implemented inside a microcontroller 28 such as illustrated in Fig. 2.
  • the disclosed 12-step trapezoidal commutation method uses a feedback control loop to improve stability and performance during commutation of a sensorless BLDC motor.
  • the control objective of the disclosed feedback controller 130 illustrated in the system block diagram 10 in Fig. 1 and in the operation flow diagram in Fig. 13, is to ensure that the open phase zero-crossing point detection window angle (co) 131 is always kept above the minimum window angle (co min ) 11. This is achieved by reducing the feedback controller’s output conduction angle (a) 14 when co 131 ⁇ oj mm 11, for example, as illustrated in Fig. 9.
  • This feedback action stabilises the commutation of a sensorless BLDC motor at very high conduction angles (a) 14, by ensuring that the open phase zero-crossing point detection window time (Tco) 139 is always sufficiently large to enable the zero-crossing points 51, 52 to be detected without errors.
  • the feedback controller 130 increases the conduction angle (a) 14 to the maximum possible conduction angle (a max ) 13, as set by the application, for example, as illustrated in Fig. 9.
  • the feedback controller 130 optimizes the phase conduction angle (a) 14 value during operation in response to different motor load and speed conditions.
  • the conduction angle (a) 14 can vary between the set minimum oi min 12 and maximum a max 13 values (eg. 120° ⁇ a ⁇ 165°), for example, as illustrated in Fig. 9.
  • the zero-crossing point detection window feedback controller operation 130 is illustrated in the operation flow diagram in Fig. 13. It begins by calculating the open phase zero-crossing point detection window angle (co) 131, using the measured open phase winding demagnetization time (TCDE)
  • the PID controller 133 sets the dynamic response of the feedback control loop, which ensures that phase conduction angle (a) 14 is adjusted sufficiently fast in response to a change in the input zero-crossing point detection window error (Dw) 132, thus increasing the stability during the 12- step commutation of a sensorless BLDC motor.
  • Ki Kp + Ki ⁇ T / 2 + Kd / T (6)
  • K 2 -Kp + Ki * T/ 2 - 2 * Kd / T (7)
  • Kp is the proportional gain
  • Ki is the integral gain
  • Kd is the derivative gain
  • T is the feedback controller update period.
  • the magnitude saturator 134 implemented in the feedback controller 130 limits the output phase conduction angle (a) 14 value computed by the PID controller 133 between the minimum oimin 138 and maximum a max 137 values set by the application, for example, as illustrated in Fig. 9.
  • the disclosed zero-crossing point detection window feedback controller 130 uses several inputs to set the desired phase conduction angle (a) 14 and the stability of operation during commutation of sensorless BLDC motors. These are: the minimum open phase zero-crossing point detection window angle (co min ) 11; the minimum phase conduction angle a min 12; and the maximum phase conduction angle a max 13.
  • the minimum zero-crossing point detection window angle (co min ) 11 can, for example, use a fixed setting value.
  • the maximum phase conduction angle a max 13 value sets maximum possible value of the phase conduction angle (a) 14 during commutation of a sensorless BLDC motor, which is regulated by the feedback controller 130, for example, as illustrated in Fig. 9.
  • the maximum phase conduction angle a max 13 setting can use a fixed value or be varied in real-time during electronic commutation, for example, with motor load or speed or command throttle position to produce a desired motor torque output.
  • the minimum phase conduction angle a min 12 value which is selected so that a stable and reliable operation can be achieved under all motor load and operating conditions, is set lower than the maximum phase conduction angle a max 13, ie. a min ⁇ a mix .
  • the minimum phase conduction angle a min 12 is set lower than the maximum phase conduction angle a max 13, ie. a min ⁇ a max .
  • Table 1 shows a range of input angle setting values which have been applied successfully in motor control applications such as electric power tools.
  • Table 1 Zero-crossing point detection window feedback controller input angle settings
  • the disclosed method of electronic commutation of a sensorless BLDC motor addresses these aforementioned instability issues with the developed zero-crossing point run-away limiter 140 unit, illustrated in the system block diagram in Fig. 1 and in the top-level operational flow diagram 30 in Fig. 10.
  • a “soft” and a “hard” zero-crossing point run-away limiter have been implemented, as illustrated in the sub-level operation flow diagrams 140a and 140b in Fig. 14 and Fig. 15 respectively.
  • the zero crossing point run-away limiter 140 monitors the behaviour of the measured open phase BEMF zero crossing voltages (eg. dV[n] illustrated in Fig.
  • phase conduction angle (a) 15 eg > 140°
  • phase conduction angle (a) 14 computed with the zero-crossing point detection window feedback controller 130, for example, as illustrated in Fig. 9.
  • a zero-crossing point run-away soft limiter 140a illustrated in Fig. 14, which decreases the output phase conduction angle (a) 15 to a minimum conduction angle (a m in) 12 at a controlled rate when the BEMF zero-crossing phase voltage exceeds the low to high (F H) 51 zero-crossing point detection voltage reference VS » NZCP_LH_RA_SOFT 142 (eg. where NZCP ui RA son 0.5 - 0.9) or the high to low (H F) 52 zero-crossing point detection voltage reference VS*NZCP HI.
  • This AOIDEC value can be set to reduce the conduction angle (a) 15 at specific rate in order to achieve the required dynamic response of the zero crossing point run -away soft limiter 140a during commutation of a sensorless BLDC motor.
  • the soft limiter 140a is not limited only to the implementation disclosed in equation (13).
  • FIG. 14 Other implementations can also be used to control the response of the zero-crossing point run-away limiter 140a, for example, such as a PID controller 133 described in equation (5) by measuring the voltage difference between the open phase BEMF voltage and half of the supply voltage rail (Vs/2) (eg. dV[n] illustrated in Fig. 6.) and using it as the input to the PID controller. Operation steps 145 and 146 illustrated in the operation flow diagram in Fig. 14 restrict the minimum phase conduction angle (a) 15 value to the set minimum conduction angle (amin) 12 value;
  • This hard limiter 140b has been implemented as an additional safety measure to prevent zero-crossing point run-away errors which may not have been corrected by the zero crossing point run-away soft limiter 140a, for example, in case the response of the soft limiter 140a was too slow to reduce the phase conduction angle (a) 15 sufficiently fast during commutation of a sensorless BLDC motor.
  • the hard limiter 140b voltage references are set, such that NZCP_LH RA HARD > NZCP_LH RA SOFT and NZCP_HL RA HARD ⁇ NZCP_HL RA SOFT.
  • the three-phase PWM output generator 170 drives the three-phase inverter power transistors (A_L, A H, B_L, B_H, C L, C_H) 23 with a 12-step commutation motor phase driving sequence illustrated in the waveform and timing diagram in Fig. 8.
  • the power transistors 23 activated during commutation steps 56 numbered 1 to 12 are shown in Table 2.
  • commutation demagnetization event (CDE) 120 and the zero- crossing point TZCP HO During the even numbered commutation steps, all three motor phases are actively driven.
  • the three-phase PWM output generator 170 commences the >120° conduction angle operation, as shown in the top-level operation flow diagram 30 in Fig. 10.
  • the commutation point (TCP) 160 sets the duration when all three motor phases are conducting current during an even numbered commutation step.
  • the TCP 160 duration is calculated with equation (1) and it depends on the value of the output phase conduction angle (a) 15, which is regulated with the zero-crossing point detection window feedback controller 130, and the measured zero-crossing point time TZCP 111 ⁇
  • the set TCP 160 value exceeds 33 the timer value 55, for example, implemented inside a microcontroller 28 the third phase is turned-off (ie.
  • commutation demagnetization event (CDE) 120 is detected next and the zero-crossing point detected flag is cleared 36. This is then followed by a new zero-crossing point T ZCP 110 detection, as shown in the top-level operation flow diagram 30 in Fig. 10.
  • any one of the terms comprising, comprised of or which comprises is an open term that means including at least the elements/features that follow, but not excluding others.
  • the term comprising, when used in the claims should not be interpreted as being limitative to the means or elements or steps listed thereafter.
  • the scope of the expression a device comprising A and B should not be limited to devices consisting only of elements A and B.
  • Any one of the terms including or which includes or that includes as used herein is also an open term that also means including at least the elements/features that follow the term, but not excluding others. Thus, including is synonymous with and means comprising.
  • exemplary is used in the sense of providing examples, as opposed to indicating quality. That is, an “exemplary embodiment” is an embodiment provided as an example, as opposed to necessarily being an embodiment of exemplary quality.
  • some of the embodiments are described herein as a method or combination of elements of a method that can be implemented by a processor of a computer system or by other means of carrying out the function.
  • a processor with the necessary instructions for carrying out such a method or element of a method forms a means for carrying out the method or element of a method.
  • an element described herein of an apparatus embodiment is an example of a means for carrying out the function performed by the element for the purpose of carrying out the invention.
  • Coupled when used in the claims, should not be interpreted as being limited to direct connections only.
  • the terms “coupled” and “connected,” along with their derivatives, may be used. It should be understood that these terms are not intended as synonyms for each other.
  • the scope of the expression a device A coupled to a device B should not be limited to devices or systems wherein an output of device A is directly connected to an input of device B. It means that there exists a path between an output of A and an input of B which may be a path including other devices or means.
  • Coupled may mean that two or more elements are either in direct physical or electrical contact, or that two or more elements are not in direct contact with each other but yet still co operate or interact with each other.

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Abstract

Procédé de commutation électronique d'un moteur à courant continu (CC) sans balais et sans capteur, le moteur comprenant une pluralité de transistors de puissance d'attaque, le procédé comprenant les étapes consistant à : (a) mesurer les tensions de phase ouverte à au moins l'un des transistors de puissance d'attaque ; (b) utiliser les tensions de phase ouverte mesurées pour déterminer le niveau de tension de démagnétisation d'enroulement de phase ; et (c) utiliser la tension de démagnétisation d'enroulement de phase pour déterminer le temps de commutation du moteur à CC sans balais.
PCT/AU2022/050371 2021-04-27 2022-04-22 Commutation électronique d'un moteur sans balais et sans capteur WO2022226579A1 (fr)

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Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8593098B2 (en) * 2008-12-10 2013-11-26 Melexis Technologies Nv Operation of BLDC motors
US9166507B2 (en) * 2013-12-26 2015-10-20 Silicon Laboratories Inc. Sensing a back electromotive force of a motor
WO2019056072A1 (fr) * 2017-09-22 2019-03-28 Janislav Sega Système et procédé de commande d'un moteur
US20200343840A1 (en) * 2019-04-25 2020-10-29 Black & Decker Inc. Sensorless variable conduction control for brushless motor

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8593098B2 (en) * 2008-12-10 2013-11-26 Melexis Technologies Nv Operation of BLDC motors
US9166507B2 (en) * 2013-12-26 2015-10-20 Silicon Laboratories Inc. Sensing a back electromotive force of a motor
WO2019056072A1 (fr) * 2017-09-22 2019-03-28 Janislav Sega Système et procédé de commande d'un moteur
US20200343840A1 (en) * 2019-04-25 2020-10-29 Black & Decker Inc. Sensorless variable conduction control for brushless motor

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
NOLAN DENNIS: "Sensorless six-step BLDC commutation ", AN4220 APPLICATION NOTE, 1 January 2013 (2013-01-01), pages 1 - 18, XP093003127, Retrieved from the Internet <URL:https://www.st.com/resource/en/application_note/an4220-sensorless-sixstep-bldc-commutation-stmicroelectronics.pdf> *

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