WO2024142095A1

WO2024142095A1 - System and method for controlling a shutdown operation of an induction motor

Info

Publication number: WO2024142095A1
Application number: PCT/IN2023/051220
Authority: WO
Inventors: Kunjimon T K
Original assignee: Pal-K Dynamics Pvt. Ltd.
Priority date: 2022-12-26
Filing date: 2023-12-24
Publication date: 2024-07-04
Also published as: WO2024142093A1; WO2024142094A1

Abstract

A system and method for controlling a shutdown operation of the induction motor. A sensor component equipped with multiple sensors, each operatively connected to the induction motor, monitor various operational parameters of the motor, for comprehensive data acquisition. The control component of the system is interfaced with the sensor component and performs real- time data processing. The control component receives sensor data and utilizes the sensor data to compute the induction motor's power factor value. A shutdown score is then calculated, which is derived from both the power factor value and the processed sensor data. When the shutdown score surpasses a pre-defined threshold, a shutdown sequence for the induction motor is initiated.

Description

SYSTEM AND METHOD FOR CONTROLLING A SHUTDOWN OPERATION OF AN INDUCTION MOTOR

TECHNICAL FIELD

[0001] This disclosure generally relates to induction motors and more specifically to a system and method for controlling a shutdown operation of an induction motor.

BACKGROUND

[0002] With the drastic increase in energy demand, various sectors, industrial or otherwise are looking to adopt sustainable forms of energy and to leverage renewable sources of energy. This is coupled with the need to provide energy-efficient devices that manage, and conserve energy/power generated, to be on par with the energy requirements and demands.

[0003] With advancements in technology, electric motors have been used in industries as a main driving power in various applications, which demand excessive use of energy resources. Specifically, induction motors such as the three-phase induction motors are predominantly used in the industrial and agricultural sectors and these motors consume 65% of the total energy produced. Thus, there is a need to save a substantial amount of energy compared to the standard conventional motors currently in use. Also, there is a need to design energy -efficient motors to reduce the running cost of such motors with improved efficiency.

[0004] There are basically two types of induction motors depending upon the type of input power supply to the motor and a type of rotor. Based on the type of input power supply, induction motors are classified as single-phase and three-phase induction motors. Based on the type of rotor, induction motors are classified as squirrel cage motors and slip ring motors or wound type.

[0005] The following is illustrative of the working principle of an inductor motor. When the stator winding of the induction motor is fed with an AC input power supply, alternating flux is produced around the stator winding due to the AC input power supply. This alternating flux revolves with synchronous speed. The alternating or revolving flux is referred to as the "Rotating Magnetic Field" (RMF). [0006] The relative speed between the stator RMF and rotor conductors causes an induced emf in the rotor conductors, in accordance with Faraday's law of electromagnetic induction. The rotor conductors are short circuited, and hence rotor current is produced due to the induced emf. Because of their operation mechanism, such motors are called as induction motors. This is similar to the action that occurs in transformers and hence induction motors are also referred to as rotating transformers.

[0007] The induced current in the rotor also produces an alternating flux around it. This rotor flux lags behind the stator flux. The direction of the induced rotor current, according to Lenz's law, is such that it will tend to oppose the cause of its production. As the cause of production of the rotor current is the relative velocity between the rotating stator flux and the rotor, the rotor tries to catch up with the stator RMF. Thus, the rotor rotates in the same direction as that of the stator flux to minimize the relative velocity. However, the rotor never succeeds in catching up with the synchronous speed of the rotating stator flux or the RMF. This is the basic working principle of both a single-phase and three-phase induction motor.

[0008] In a three-phase induction motor, the three-phase supply is used to balance the consumption of high current. Hence, the three-phase supply is required to run an induction motor with a 3 HP rating and more.

[0009] Energy efficiency of electric motors especially the induction motors, is a highly researched area. By increasing the efficiency of induction motors, it is possible to conserve tremendous amounts of energy. It is difficult to achieve industrial efficiency standards using conventional design approaches for designing the induction motors.

[0010] In conventional induction motors, the power factor varies with load, typically from around 0.85 to 0.90 at full load to as low as around 0.20 at no-load conditions. During the no- load condition, an induction motor draws a large magnetizing current and a small active component in order to meet the no-load losses. Therefore, the induction motor takes on a high no-load current lagging the applied voltage by a large angle. In view of this, the power factor of an induction motor on no load is extremely low.

[0011] Hitherto known low power (for example, less than 5 HP) induction motors cannot operate at a power factor of over 0.90 and would cut off based on maximum load principle. Thus, in conventional induction motors, the efficiency is always decided by the load on the induction motor. Also, conventional induction motors cannot work in both single-phase and three-phase power supply. Furthermore, conventional induction motors work within 10% tolerance on the voltage range ratings specified against such motors. For instance, a motor that is designed to operate for 220 V will not function for other voltages.

[0012] CN201663527U relates to an electric drive system design. An electric forklift alternating current drive system is a cage induction motor. A three-phase winding is placed in a slot in the inner circumference of a stator. A closed rotor generating rotary magnetic field induction generates current. The three-phase winding space of the electric forklift alternating current drive system is arranged according to 120-degrees potential difference. The rotor type is that a squirrel-cage rotor is formed by a cast aluminum strip in a rotor outer edge slot. After constant voltage frequency analogy control uses sine Pulse Width Modulation (PWM) and a DC/AC inverter for inversion, the voltage is 48V. The fundamental frequency of the electromotor is identical with the frequency of sine wave reference voltage. The elements required by an alternating current electromotor are greatly reduced, no easily damaged parts need regular replacement, and maintenance is nearly not necessary. Compared with a direct current electromotor, the electromotor is more efficient, firmer and more durable.

[0013] US4414499A discloses a motor protecting improved energy economizer for induction motors. A standard, unmodified AC induction motor has its stator winding energized from a sine wave source through a signal-responsive wave modifier operative to control the portion of each cycle of the sine wave which is coupled from said source to the stator winding. An improved motor current demodulator, responsive to efficiency-related parameters and excessive stator winding inrush current each time said current increases from zero, produces signals for controlling the wave modifier, thereby to maintain optimum motor efficiency with varying motor loads and power source variations, and the signals also control a motor protector circuit which inhibits said wave modifier thereby to deenergize said stator winding under excessive input current conditions, excessive motor temperature or a potentially damaging combination thereof.

[0014] US4382223A relates to a voltage and frequency-controlled AC wave modifier. A standard, unmodified AC induction motor has its stator winding energized from a sine wave power source through a signal-responsive wave modifier operative to control the portion of each cycle of the sine wave which is coupled from said source to the stator winding. Load detecting means, comprising a comparatively small AC generator coupled to the rotor of the motor, produces a control signal, varying with variations in the load on the motor, for controlling the wave modifier to increase the field density of the stator winding with increase in load on the motor, and to decrease the field density of the stator winding with decrease in load.

[0015] US4864212A discloses an energy economizing AC power control system for energizing an induction motor. Here it describes a sine wave power source connected through a TRIAC to a control system with a gate electrode which is energized by a train (sequence) of sawtooth-shaped control signals having a repetition rate which is twice the frequency of the sine wave power source for providing short bursts of energy to decrease total power input for low power requirements at low fixed rates for variable rates of low-speed operation.

[0016] US4341984A discloses an electronic commutation for direct current electric motors. A direct current electric motor comprises a stator consisting of a plurality of coils interconnected to one another, and a plurality of gate controlled solid state rectifiers responsive to forced commutation below a particular rpm and self-commutation above said rpm which are connected to the junctions of the coils for selectively conducting current into and out of the stator coil junctions in dependence upon which of said rectifiers is rendered operative. This produces a plurality of stator poles which are angularly displaced from the poles of the rotor of the motor and which shift in position as the rotor rotates. A plurality of trigger assemblies are provided for controlling the energization of the various gate electrodes, each of said trigger assemblies comprising a pick-up coil which forms a portion of a frequency selective circuit whose resonance frequency varies in dependence on the position of a magnetic element that is moved relative to the pick-up coils as the rotor rotates. A sine wave oscillator is coupled to the frequency selective circuits in the trigger assemblies, the oscillator being operative to produce either of two different output frequencies, or an electronic switch responsive to the speed of rotation of the rotor selectively changes the output frequency of the oscillator. One of these frequencies induces trigger assembly operation at all rotor positions and advanced SCR trigger timing for reliable starting and very low speed operation. The other frequency retards SCR trigger timing for most efficient motor running at moderate and high speeds. [0017] US4636702A discloses an energy economizer controlled-current start and protection for induction motors. This document describes a sample transformer operative to generate a voltage pulse related to inrush-current parameters for control of portions of sine waves of power input to stator windings for diminishing electrical current to a motor during low loading. It is limited further to a “manually settable means” for selecting a maximum value of motor torque during start mode of operation.

[0018] US6489742B2 discloses an efficiency-maximization motor controller that includes a use method has power conveyance to an induction motor with a digital signal processor (DSP) that calculates and optimizes supply of current for existent motor loading from a power supply and mains voltage through a control element. The control element can include a standard TRIAC, a field-effect transistor, an insulated gate bipolar transistor, a three quadrant TRIAC or other select control element. Digital calculation and motor-control feedback of current requirements for motor loading and other motor parameters are calculated in millionths of seconds to provide motor-current optimization for all motor-use conditions. Calculation of motor-load requirement for current and supply of that current are effectively simultaneous.

[0019] Limitations and disadvantages of conventional and traditional approaches will become apparent to one of ordinary skill in the art, through comparison of described systems with some aspects of the present disclosure, as set forth in the remainder of the present application and with reference to the drawings.

SUMMARY

[0020] A system and method is disclosed for controlling a shutdown operation of an induction motor, as shown in and/or described in connection with, at least one of the figures.

[0021] In an example implementation, a system for controlling a shutdown operation of an induction motor includes a sensor component which includes a plurality of sensors operatively connected to the induction motor. The sensor component is configured to monitor at least one operational parameter of the induction motor. The system further includes a control component interfaced with the sensor component. The control component is configured to receive and process sensor data from the sensor component in real-time, compute a power factor value of the induction motor using the processed sensor data, calculate a shutdown score based on the computed power factor value and the processed sensor data, and initiate a shutdown sequence for the induction motor when the shutdown score exceeds a pre-set threshold.

[0022] In an aspect combinable with the example implementation, the plurality of sensors include at least one of voltage sensors, current sensors, temperature sensors, vibration sensors, and speed sensors torque sensors, and acoustics sensors.

[0023] In another aspect combinable with any of the previous aspects, the at least one operational parameter includes at least one of stator-rotor interaction, voltage, current, slip, torque and frequency supplied to the induction motor.

[0024] In another aspect combinable with any of the previous aspects, the control component includes a machine learning module to adaptively adjust the shutdown score calculation based on historical data.

[0025] In another aspect combinable with any of the previous aspects, the system further includes a feedback mechanism within the control component configured to adjust future shutdown thresholds and parameters based on operational data collected during and after shutdown events.

[0026] In another aspect combinable with any of the previous aspects, the shutdown sequence includes steps to gradually reduce speed and power consumption of the induction motor in a manner that minimizes wear and tear. [0027] In another aspect combinable with any of the previous aspects, the control component is configured to assign and dynamically adjust weights to different sensor data based on heuristic rules tuned based on correlations observed over time.

[0028] In another aspect combinable with any of the previous aspects, the control component is configured to normalize and weight the sensor data, for calculating the shutdown score.

[0029] In another example implementation, an induction motor includes a stator comprising a main winding (M) for generating a rotating magnetic field (RMF) upon providing a main AC power supply to the main winding (M) of the stator, and a rotor disposed to rotate relative to the main winding (M) of the stator due to the RMF. The stator further includes an auxiliary winding (A), wherein rotation of the rotor induces an alternating EMF in the auxiliary winding (A) of the stator. The alternating EMF produced in the auxiliary winding (A) is fed back to the main winding (M) of the stator throughout a complete rotation cycle of the rotor through an electronic control unit (ECU) coupled to the stator. The ECU includes the system described above for controlling the shutdown operation of the induction motor.

[0030] In another example implementation, an electric vehicle includes the induction motor described above.

[0031] In another example implementation, a method for controlling a shutdown operation of an induction motor includes obtaining sensor data from a sensor component operatively connected to the induction motor, the sensor component including a plurality of sensors, processing the sensor data received from the sensor component in real-time, computing a power factor value of the induction motor using the processed sensor data, calculating a shutdown score based on the computed power factor value and the processed sensor data, and initiating a shutdown sequence for the induction motor when the shutdown score exceeds a pre-set threshold.

[0032] In an aspect combinable with the example implementation, the method includes calculating the shutdown score comprises adaptively adjusting the shutdown score calculation based on historical data using a machine learning module. [0033] In another aspect combinable with any of the previous aspects, the method further includes adjusting future shutdown thresholds and parameters based on operational data collected during and after shutdown events using a feedback mechanism.

[0034] In another aspect combinable with any of the previous aspects, the method of initiating the shutdown sequence includes initiating steps to gradually reduce speed and power consumption of the induction motor in a manner that minimizes wear and tear.

[0035] In another aspect combinable with any of the previous aspects, the method further includes assigning and dynamically adjusting weights to different sensor data based on heuristic rules tuned based on correlations observed over time.

[0036] In another aspect combinable with any of the previous aspects, the method of assigning and dynamically adjusting weights to different sensor data includes normalizing and weighting the sensor data, for calculating the shutdown score.

[0037] These and other features and advantages of the present disclosure may be appreciated from a review of the following detailed description of the present disclosure, along with the accompanying figures in which like reference numerals refer to like parts throughout.

BRIEF DESCRIPTION OF THE DRAWINGS

[0038] FIG. 1A is a schematic depicting various components and working of an energyefficient induction motor in accordance with an exemplary implementation of the disclosure.

[0039] FIG. IB is a schematic depicting components of an electronic control unit (ECU) of the induction motor in accordance with an exemplary implementation of the disclosure.

[0040] FIG. 2A is a schematic representation of a stator of a single-phase induction motor in accordance with an exemplary implementation of the disclosure. [0041] FIG. 2B is a diagrammatic representation of a connection configuration between a main winding and an additional auxiliary winding of the stator to achieve high power factor in accordance with an exemplary implementation of the disclosure.

[0042] FIG. 3 is a schematic representation of a rotor of a single-phase induction motor in accordance with an exemplary implementation of the disclosure.

[0043] FIG. 4 is a schematic of an example implementation of the induction motor in an electric vehicle in accordance with an exemplary embodiment of the disclosure.

[0044] FIG. 5 illustrates a flowchart of a method for controlling a shutdown operation of an induction motor in accordance with an exemplary implementation of the present disclosure.

DETAILED DESCRIPTION

[0045] The following described implementations may be found in the disclosed system and method for controlling a shutdown operation of an induction motor using sensor data.

[0046] FIG. 1A is a schematic depicting various components and working of an energyefficient high power factor induction motor in accordance with an exemplary implementation of the disclosure. Referring to FIG. 1A, there is shown an induction motor 100 comprising a stator 102 and a rotor 104, a single-phase or three-phase main AC power supply 106, a main winding (M) of the stator 102, one or more additional auxiliary windings (A) of the stator 102, a rotating magnetic field (RMF) 108 generated in the main winding (M), an alternating EMF 110 produced in the one or more additional auxiliary windings (A), an electronic control unit (ECU) 112, a control device 114, a resultant AC output power 116 and a load 118 of the induction motor 100.

[0047] The stator 102 comprises the main winding (M) and the one or more additional auxiliary windings (A). Respective terminal ends of the main winding (M) and the one or more additional auxiliary windings (A) are connected to the ECU 112. [0048] The main winding (M) of the stator 102 generates the RMF 108 upon connecting the main AC power supply 106 to the main winding (M) to provide the power input. The main AC power supply 106 is either single-phase or three-phase power supply.

[0049] The rotor 104 is disposed to rotate relative to the main winding (M) of the stator 102 due to the RMF 108 produced in the main winding (M). The one or more additional auxiliary windings (A) of the stator 102 produces the alternating EMF 110 which is induced in the one or more additional auxiliary windings (A) due to the rotation of the rotor 104.

[0050] The alternating EMF 110 produced in the one or more additional auxiliary windings (A) is then harvested, manipulated and fed back simultaneously to the main winding (M) of the stator 102 throughout the complete and/or fractional rotation cycle of the rotor 104 through the ECU 112 coupled to the stator 102. The energy (alternating EMF 110) thus produced during the rotation of the rotor 104 meets a major part of the energy requirement of the induction motor 100, as the induction motor 100 partly functions as a generator.

[0051] The alternating EMF 110 produced in the one or more additional auxiliary windings (A) of the stator 102 is fed to the ECU 112. The ECU 112 converts AC voltage of the main AC power supply 106 and the alternating EMF 110 produced in the one or more additional auxiliary windings (A) to respective DC powers. A resultant DC power is obtained by adding the respective DC powers.

[0052] The resultant DC power is then converted to the resultant AC output power 116 by circuitry in the ECU 112. The ECU 112 then feeds the resultant AC output power 116 to the main winding (M) of the stator 102. Thus, the stator 102 is continuously supplied only with the resultant AC output power 116.

[0053] The control device 114 is pivotal to the functioning of the ECU 112. The control device 114 controls the supply power/energy (RMF 108) required for rotating the rotor 104 and for driving the load 118 by providing the required torque, frequency, and power (alternating EMF 110) generated by the rotor 104 while it is rotating. The control device 114 is located either within the ECU 112 or is external to the ECU 112. The control device 114 may include, but need not be limited to, a microcontroller, a digital signal processor (DSP), or a microprocessor or a network operated computing device external to the ECU 112. [0054] The main AC power supply 106 provides power to the ECU 112, which in turn carries out its functions and provides the required power or torque to the induction motor 100 for driving the load 118. The energy required to develop the torque is provided collectively by the main power line of the main AC power supply 106 and the alternating EMF 110 generated in the one or more additional auxiliary windings (A) of the stator 102 due to the rotation of the rotor 104.

[0055] In accordance with an exemplary implementation, the one or more additional auxiliary windings (A) are connected to the main winding (M) of the induction motor in a specific configuration to achieve a high power factor, thus reducing the harmonics encountered during the operation of the induction motor 100. The shape of the stator core slots in conjunction with the connection configuration of the one or more additional auxiliary windings (A) with the main winding (M), helps to reduce heat and noise produced during the operation of the induction motor 100, thus improving the efficiency of the induction motor 100. The details related to the specific connection configuration of the windings is further described in conjunction with FIG. 2B.

[0056] The induction motor 100 operates based on the decision logic of the ECU 112 which controls parameters such as, but not limited to, speed, torque, input current requirements and heat. The decision logic of the ECU 112 controls a function of the one or more additional auxiliary windings (A) in the induction motor 100 operating in single phase, based on parameters such as, but not limited to, speed, and load to switch between the main winding (M) and the one or more additional auxiliary windings (A).

[0057] The ECU 112 is further programmed with a shutdown logic for the induction motor 100, which is triggered based on the power factor values rather than the load parameters. The induction motor 100 is wholly controlled by the ECU 112 based on multiple parameters obtained from the induction motor 100.

[0058] The above design and construction of the induction motor 100 enables the induction motor 100 to work both as a single-phase and three-phase induction motor. Further, the induction motor 100 is capable of operating at an input voltage range of 100V to 440V, thus making it usable for different operating voltages. [0059] The induction motor 100 is designed to operate at a very high power factor, of greater than 0.95, irrespective of the power rating of the motor.

[0060] Further, the shutdown logic of the induction motor 100 is intelligently programmed based on the power factor principle (-0.99) rather than the rated load parameter principle, reducing the overall harmonic losses including the heat and noise of the induction motor 100. This is possible with slow speed, high speed, low power or high power motors. The efficiency of the induction motor 100 is obtained during the initial fraction of the input voltage cycle provided. Both load and speed characteristics determine the power factor of the induction motor 100, thus reaching the maximum power factor on optimum speed.

[0061] In accordance with an implementation, when the induction motor 100 is connected to a three-phase power supply, the entire main winding (M) of the induction motor 100 is provided with the supply voltage and current to start the induction motor 100. On the other hand, when the induction motor 100 is connected to a single-phase power supply, the one or more additional auxiliary windings (A) inside the induction motor 100 are initiated as a starting winding for the required torque along with the main winding (M) by the ECU 112. Once the induction motor 100 reaches the rated speed or torque, the one or more additional auxiliary windings (A) serve as the efficiency winding and thus function towards improving the power factor and therefore the overall efficiency of the induction motor 100.

[0062] The ECU 112 intelligently controls the induction motor 100 for improving the power factor and to shut down the entire system based on the power factor. Thus, the power factor achieved in such a configuration is above 0.95, leading to very high efficiencies. The ECU 112 intelligently monitors the power generation in the one or more additional auxiliary windings (A) and the extra power from the one or more additional auxiliary windings (A) is re-routed to the input of the induction motor 100, thus reducing the overall input power requirements. This is further illustrated as follows:

[0063] During the initial fraction of the input voltage cycle to the induction motor 100,

Total input power (PI) = Input Power from Source (PI_S) [0064] Once the optimum speed/torque is reached after a fraction of the input voltage cycle or input cycle of power,

Total Input Power (PI) = Input Power from Source (PI_S) + Power contributed by the one or more additional auxiliary windings (A) (PI_a)

[0065] Further, the ECU 112 is intelligently programmed to shut down the induction motor 100 once the power factor reaches 0.99, and thus the induction motor operates independent of the load characteristics.

[0066] In accordance with another exemplary implementation, due to a reduced size and shape of the induction motor 100, multi -motor configuration may be implemented for high torque and load, which in turn provides for a higher load bearing capability of the induction motor 100, thus achieving a high power output and therefore, a high power factor and efficiency.

[0067] The multi-motor configuration provides higher efficiency and power factor due to multiple motor auxiliary windings being fed back to the motors to reduce the input power requirements.

[0068] FIG. IB is a schematic illustration of an example implementation of the ECU 112 of the induction motor 100. Referring to FIG. IB, there is shown the ECU 112 that includes a system 120 for controlling a shutdown operation of the induction motor 100. It is also shown in FIG. IB that the system 120 includes a sensor component 122 and a control component 124. The control component 124 is shown to further include a computation component 126, a shutdown controller 128, a machine learning module 130, a feedback mechanism 132 and an adjustment mechanism 134.

[0069] The sensor component 122 may comprise suitable logic, interfaces, and/or code that may be configured to monitor one or more operational parameters of the induction motor 100. The sensor component 122 may include multiple sensors that may include, but is not limited to, current sensors, voltage sensors, temperature sensors, speed sensors (e.g., tachometers), position sensors (e.g., encoders), vibration sensors, torque sensors, hall effect sensors, flux sensors, pressure sensors and humidity sensors. An operational parameter that is monitored by the sensor component 122 may include, but is not limited to, stator-rotor interaction, voltage, current, slip, torque and frequency supplied to the induction motor 100. [0070] The control component 124 is communicatively coupled to the sensor component 122. The control component 124 may comprise suitable logic, interfaces, and/or code that may be configured to receive sensor data from the sensor component 122, and process the received sensor data.

[0071] The computation component 126, which is a part of the control component 124, may comprise suitable logic, interfaces, and/or code that may be configured to compute a power factor (PF) value of the induction motor 100 using the processed sensor data. The computation component 126 is further configured to calculate a shutdown score based on the computed power factor value and the processed sensor data.

[0072] A shutdown controller 128, which is a part of the control component 124, may comprise suitable logic, interfaces, and/or code that may be configured to initiate a shutdown sequence for the induction motor when the shutdown score exceeds a pre-set threshold. The shutdown sequence includes steps to gradually reduce speed and power consumption of the induction motor in a manner that minimizes wear and tear.

[0073] The machine learning module 130 (also known as the decision logic module 130), which is a part of the control component 124, may comprise suitable logic, interfaces, and/or code that may be configured to adaptively adjust the shutdown score calculation based on historical data.

[0074] The control component 124 specifically focuses on the voltage and current waveforms, and processes the sensor data to compute the phase difference ((|)) by activating the computation component 126, with power factor (PF) calculated as F=cos((|)) . Based on the computed PF, the control component 124 makes decisions about the operational state of the induction motor 100 using the decision logic module 130. For instance, the control component 124 causes the shutdown controller 128 to initiate a shutdown or a transition to standby if PF is > 0.99, maintain operation with close monitoring if PF is between 0.95 and 0.99, or flag inefficiencies if PF drops below 0.95.

[0075] The feedback mechanism 132 within the control component 124, may comprise suitable logic, interfaces, and/or code that may be configured to adjust future shutdown thresholds and parameters based on operational data collected during and after shutdown events. The feedback mechanism 132 is configured to provide real-time updates about any operational changes in the induction motor 100. The feedback mechanism 132 is configured to alert the control component 124 in the event of load changes, voltage fluctuations, or other transient events, enabling immediate recalculation of the PF.

[0076] The adjustment mechanism 134 within the control component 124, may comprise suitable logic, interfaces, and/or code that may be configured to assign and dynamically adjust weights to different sensor data based on heuristic rules tuned based on correlations observed over time. The adjustment mechanism 134 is further configured to normalize and weight the sensor data, for calculating the shutdown score.

[0077] In an implementation, the steps executed in the decision logic module 130 for effecting shutdown based on power factor of the induction motor is detailed as follows.

[0078] A first step includes setting a desired operational efficiency threshold. For instance, a predefined threshold power factor value is set as 0.90 (PFthreshoid = 0.90). This value may be the benchmark below which the induction motor 100 may be deemed inefficient. The threshold power factor is typically determined based on the desired operational efficiency of the induction motor 100 and the specific applications the induction motor 100 is being used for.

[0079] In a second step, the control component 124 continuously gathers essential data through integrated sensors of the sensor component 122. This data may include, but is not limited to, voltage and current readings of the induction motor 100 to calculate the power factor, temperature and load (torque) of the induction motor 100, and additional metrics from sensors such as, but not limited to, vibration sensors, acoustic sensors, and humidity sensors. The control component 124 continues to monitor the power factor value of the induction motor 100. If the power factor value drops and stays below PFthreshoid for an extended duration, the control component 124 flags the value for further checks.

[0080] In some implementations, before any decision, the control component 124 conducts additional checks. For instance, the control component 124 evaluates temperature of the induction motor 100 against a set threshold and gauges the load of the induction motor 100. If the temperature breaches its maximum limit or if the load falls below the set threshold, the control component 124 underscores inefficiencies or potential operational risks associated with the induction motor 100. [0081] The Integrated Sensor Data (Sdata) is a composite metric derived from various sensor readings and data points managed by the control component 124, such as, but not limited to, voltage and current fluctuations, speed monitoring, vibration and acoustic data, olfactory data, feedback from auxiliary systems and historical data. Given that each sensor produces data in different units and ranges, the data from the sensors are initially normalized. Once normalized, weights are assigned to each sensor by the adjustment mechanism 134, which represents its importance or relevance in the context of shutdown of the induction motor 100. For instance, temperature readings might be more critical than humidity readings in some scenarios.

[0082] A rule-based algorithm a rule-based algorithm for sensor weight assignment in the control component 124 involves several key steps.

[0083] To define sensor significance, initial importance levels are assigned to sensors based on domain expertise. The weights represent the expected influence of the sensor data on the power factor. For example, a high load variance might be known to cause more reactive power, affecting the power factor negatively, and the temperature parameter may be more critical than vibration. Therefore, sensors measuring load variance and temperature may be assigned higher weights than those measuring vibration, due to their direct impact on power factor.

[0084] Thresholds and conditions may be established for sensor readings that indicate critical conditions. For example, a temperature exceeding a certain level might indicate an impending shutdown.

[0085] Further, rules are defined for adjustment of weights. For instance, rules are defined for adjusting weights based on the following operating conditions: If increased load variability is often followed by a significant drop in power factor, increase the weight of the load sensor. If a rise in temperature of the induction motor 100 correlates with a decrease in efficiency and power factor, increase the weight of the temperature sensor.

[0086] The feedback mechanism 132 reviews the effectiveness of the weight adjustments is reviewed. If certain sensor readings lead to successful predictive adjustments in the operation of the induction motor 100 that maintain a high-power factor, their weights should be increased. [0087] The dynamic adjustment mechanism 134 updates sensor weights based on their performance overtime. For instance, a decay factor for sensors that have not shown significant correlations recently is implemented, reducing their weights gradually. In another instance, a boost factor for sensors that have recently shown a strong correlation with events are incorporated that typically result in power factor changes.

[0088] The dynamic adjustment mechanism 134 (weighting system 134) is regularly reviewed and evaluated to ensure it is in line with the current operating conditions and performance targets. The rules are adjusted as necessary to maintain the accuracy of the sensor weightings. These weighted values from the various sensors are then combined to form Sdata.

[0089] Using the data gathered and processed, the control component 124 computes a shutdown score using the equation:

Shutdown_Score= Wl X ( 1— PF) + W2 X T/Tmax + W3 X (1 - T/Tmax) + W4 ^x Sdata where,

[0090] wi x (1-PF) = This component captures the deviation of the power factor from the ideal value of 1. The weighting factor wi determines the significance of this component in the overall score, wi can be dynamically adjusted based on real-time operational conditions. For instance, during peak operational times, the control component 124 could prioritize efficiency and adjust wi to be more sensitive to power factor deviations. Conversely, during off-peak times, wi could be relaxed to prioritize longevity over efficiency.

[0091] W2 ^x T/Tmax = This term evaluates temperature T of the induction motor 100 against a predefined maximum allowable temperature Tmax. The weighting factor W2 establishes the importance of temperature in the decision-making process. The historical performance of the induction motor 100 under varying temperature conditions will be considered. If the induction motor 100 demonstrates resilience to higher temperatures without efficiency loss, W2 could be reduced accordingly. Conversely, if temperature spikes correlate with performance issues, W2 could be increased, making the system more responsive to thermal conditions.

[0092] W3 ^x (1 - T/Tmax) = This term assesses the load (torque r) on the induction motor 100 relative to its maximum designed load Tmax. The weighting factor W3 ascribes significance to this load-based component. If the induction motor 100 shows signs of wear or reduced performance under certain load conditions, W3 can be increased to reflect this in the shutdown score, prompting earlier shutdowns under those conditions.

[0093] W4 ^x Sdata = This term integrates a holistic assessment of the operational condition of the induction motor 100 based on a diverse array of sensor inputs. The weighting factor W4 acts as a scaling factor to ensure that the Sdata metric contributes appropriately to the shutdown score.

[0094] The weighting factors wi, W2, W3, and W4 will be set by engineers and system designers based on their knowledge of motor operations and the criticality of each factor. If this score surpasses a set threshold, the control component 124 is configured to transmit commands to the shutdown controller 128 to initiate the shutdown sequence. If the Shutdown_Score exceeds a pre-defined threshold, the shutdown controller 128 triggers the intelligent shutdown sequence or transitions the induction motor 100 to a safer operational state. This ensures that the shutdown decision is comprehensive, considering both primary motor operational metrics and a wide array of sensor data.

[0095] In some implementations, instead of a simple threshold-based shutdown, the induction motor 100 may have multiple 'states' or 'modes' of operation that are engaged based on the shutdown score range. A high score might trigger an immediate shutdown, a medium score could trigger a reduced-power mode, and a low score could maintain normal operation.

[0096] The above provided implementations present an approach to controlling the shutdown operation of the induction motor 100. Further modifications and alternative embodiments of various aspects will be apparent to those skilled in the art in view of this description.

[0097] FIG. 2A is a diagrammatic representation of a stator of a single-phase induction motor in accordance with an exemplary implementation of the disclosure. Referring to FIG. 2A, there is shown a stator 200 of the single-phase induction motor 100, which includes a frame or yoke 202, a stator core 204, stator slots 206 and stator windings 208.

[0098] The frame or yoke 202 is made of close-grained alloy cast iron or aluminum alloy and forms an integral part of the stator 200. The main function of the frame or yoke 202 is to provide a protective cover for other sophisticated components or parts of the single-phase induction motor 100. The stator core 204 is made up of laminations which include the stator slots 206 that are punched from sheets of electrical grade steel. The space provided in the stator slots 206 is sufficient to accommodate the stator windings 208 that include one or more sets of winding wires. In related aspects, the space provided in the stator slots 206 may be more than in conventional slots. The winding wires are insulated wires. The size of the stator slots 206 may be adjusted and maintained for uniform distribution of the stator windings 208.

[0099] The space provided in the stator slots 206 is configured to accommodate the one or more sets of winding wires which include the main winding (M) which carries the supply power/energy (RMF) required for rotating the rotor and the one or more additional windings (A) which is used for transmission of the power (alternating EMF) induced in the one or more additional windings (A) while the rotor is rotating. The energy produced during the rotation of the rotor meets part of the energy requirement of the single-phase induction motor 100, as the induction motor 100 partly functions as a generator.

[00100] Further, the stator 200 includes rabbets and bore that are machined carefully to ensure uniformity of air gap. The shaft and bearings used in the stator 200 of the induction motor 100 are like any other conventional induction motor. A ball bearing of suitable size is used to reduce rotational friction and support radial and axial loads. A fan is provided to enable adequate circulation of air to cool the stator windings 208. The heat produced in the induction motor 100 is comparatively less because of less current consumption and due to mutually opposite working of the stator windings 208 namely, the main winding (M) corresponding to supply power/energy required for rotating the rotor and the one or more additional windings (A) corresponding to transmission of the power generated in the one or more additional windings (A) while the rotor is rotating. Therefore, the size of the cooling fan can also be reduced, thus saving some energy on that count. The bearings are housed at the end of the shaft and are fixed to the frame or yoke 202.

[00101] A number of poles and a number of windings that will be required for the stator

200 is decided based on the speed of the induction motor 100 as the synchronous speed is directly proportional to frequency and inversely proportional to the number of poles according to the equation, Ns = 120f/P, wherein ‘Ns’ is the synchronous speed, is the frequency and ‘P’ is the number of poles. [00102] FIG. 2B is a diagrammatic representation of a connection configuration between a main winding and an additional auxiliary winding of the stator to achieve high power factor in accordance with an exemplary implementation of the disclosure. Referring to FIG. 2B, there is shown a main coil 202 of the stator with a start terminal (M_s) and an end terminal (M_e) and an auxiliary coil 204 with a start terminal (A_s) and an end terminal (A_e).

[00103] As depicted in FIG. 2B, the start terminal (A_s) of the auxiliary coil 204 is connected to the end terminal (M_e) of the main coil 202.

[00104] The ECU 112 feeds the back EMF power (Pl) generated by flux cutting from main coil 202 into the auxiliary coil 204 connected in reverse to the main coil 202. At the same time, a back EMF (P2) is also created at auxiliary coil 204, Thus, a total power of Pl + P2 is available in the auxiliary coil 204 and this phenomenon is replicated in all the coils using the main and auxiliary windings with the help of the ECU 112.

[00105] The ECU 112 of the induction motor 100 receives the back EMF from the stator coils and provides the same to the auxiliary windings. Thus, the main winding and the multiple auxiliary windings are enabled with more than one power component being feed to each winding. Each winding has more than one power component enabling an efficiency component as:

• Power Component generated from the back EMF induced from the previous coil due to flux cutting.

• Power component generated by the back EMF at the coil due to flux cutting while the rotor 104 is rotating the magnetic field (RMF).

[00106] The above-described connection configuration of the windings reduces the input current component.

[00107] FIG. 3 is a diagrammatic representation of a rotor of a single-phase induction motor in accordance with an exemplary implementation of the disclosure. Referring to FIG. 3, there is shown a rotor 300 which includes steel laminations 302, aluminum bars 304, a rotor shaft 306 and end rings 308. [00108] In this particular implementation, the rotor 300 is a squirrel cage type rotor. The rotor 300 includes a cylinder of the steel laminations 302, with the aluminum bars 304 for separating the steel laminations 302 of the rotor 300. In some implementations, the rotor 300 may include highly conductive metal (typically aluminum or copper) embedded into its surface, parallel or approximately parallel to the rotor shaft 306 and close to the surface of the rotor 300. At both ends of the rotor 300, rotor conductors are short-circuited by the continuous end rings 308 of similar materials to that of the rotor conductors. The rotor conductors and their end rings 308 by themselves form a closed circuit.

[00109] When an alternating current is run through the stator windings 208, the RMF is produced. This induces a current in the rotor windings, which produces its own magnetic field. The interaction of the magnetic fields produced by the stator and rotor windings produces a torque on the rotor 300.

[00110] The RMF induces voltage in the rotor bars which causes short-circuit currents to start flowing in the rotor bars. These rotor currents generate their self-magnetic field which interacts with the RMF of the stator 200. The rotor field will try to oppose its cause, which is the RMF. Therefore, the rotor 300 starts following the RMF. The moment the rotor 300 catches up with the RMF, the rotor current drops to zero as there is no more relative motion between the RMF and the rotor 300. Hence, when the rotor 300 experiences zero tangential force, the rotor 300 decelerates for the moment. After deceleration of the rotor 300, the relative motion between the rotor 300 and the RMF is reestablished, and consequently, a rotor current is induced again. Thus, the tangential force for rotation of the rotor 300 is restored again, and the rotor 300 starts rotating again following the RMF. In this way, the rotor 300 maintains a constant speed which is less than the speed of the RMF or the synchronous speed (Ns).

[00111] FIG. 4 is a schematic of an example implementation of the induction motor 100 in an electric vehicle. Referring to FIG. 4, there is shown an electric vehicle 400, the induction motor 100, a battery pack 402, a charging system 404, a power inverter 406, a transmission 408 and a thermal management system 420. The electric vehicle 400 includes a vehicle control unit (VCU) 410, auxiliary systems 412, sensors and actuators 414, a user interface 416 and a regenerative braking system 418. [00112] The description above of the components, features, processes, advantages and/or functionality of the induction motor 100 of FIG. 1A and FIG. IB apply mutatis mutandis to the induction motor 100 of FIG. 4.

[00113] The battery pack 402 is the primary source of electrical energy for the electric vehicle 400, storing power to be used by the induction motor 100 and other electrical systems . The charging system 404 manages the charging of the battery pack 402 from an external power source. The charging system may include onboard chargers and potentially regenerative braking systems that convert mechanical energy back into electrical energy during braking.

[00114] The power inverter 406 converts the DC power from the battery pack 402 into AC power suitable for the induction motor 100. The transmission 408 transfers mechanical power from the induction motor 100 to the wheels of the electric vehicle 400.

[00115] The VCU 410 acts as the central processing unit of the electric vehicle 400, managing various subsystems, including, but not limited to, the drive control, battery management, and thermal management systems. The auxiliary systems 412 includes components such as, but not limited to, lighting, infotainment, and climate control, which are powered by the electrical system of the electric vehicle 400.

[00116] The sensors and actuators 414 include various sensors such as, but not limited to, speed, temperature, and current sensors and actuators are essential for providing feedback to the control systems and ensuring safe and efficient operation of the electric vehicle 400. The user interface 416 includes the dashboard, which provides information to the driver about the vehicle's status (battery level, speed, etc.) and receives input from the driver (acceleration, braking, etc.).

[00117] Optionally, there may be a regenerative braking system 418 in the electric vehicle 400 which recovers energy during braking and feeds it back into the battery pack 402.

[00118] The thermal management system 420 maintains optimal operating temperatures for the battery pack 402, the induction motor 100, and other electronic components.

[00119] Further modifications and alternative embodiments of various aspects will be apparent to those skilled in the art in view of this description.

[00120] The speed-centric approach to optimizing efficiency in control systems (e.g., control system 120 of the induction motor 100) of electric vehicles (e.g., electric vehicle 400) offers several advantages over the traditional load-centric approach, particularly in terms of operational efficiency across various conditions. Electric vehicles operate under dynamic conditions, frequently encountering changes in speed due to accelerations, decelerations, uphill climbs, and more. A speed-centric approach is adept at optimizing efficiency across these varying speeds, unlike a load-centric motor that might only achieve peak efficiency at a specific load point.

[00121] Additionally, speed-centric motors, equipped with feedback loops and Electronic Control Units (ECUs), can rapidly adjust their operations to changes in the desired speed. This quick response capability ensures minimal deviations from optimal efficiency, even during abrupt speed changes such as rapid accelerations or decelerations.

[00122] In scenarios like regenerative braking, which focuses more on controlling speed than load, the speed-centric approach proves to be more effective. Precise speed control efficiently converts kinetic energy back into stored energy in the battery pack 402. Furthermore, consistently higher efficiency across diverse driving conditions means that the electric vehicle 400 with a speed-centric induction motor 100 would have an extended driving range on a single battery charge, compared to one with a load-centric motor. The closer match between desired and actual speeds in speed-centric systems also reduces wear and tear on the motor components, potentially extending the lifespan of the induction motor 100. Modem EVs often feature integrated systems where the induction motor 100, battery management system, and other components communicate seamlessly. A speed-centric approach enhances the synergy between these systems, leading to improved overall vehicle performance.

[00123] While load-centric motors can achieve high peak efficiencies under optimal conditions, their efficiency often drops significantly under dynamic driving conditions. In contrast, a speed-centric induction motor 100 maintains a more consistent efficiency level across a broader range of speeds and conditions. This consistency makes the speed-centric approach more suitable for EVs, aligning with their operational demands and contributing to overall energy efficiency and user satisfaction.

[00124] FIG. 5 is a flowchart of a method for controlling a shutdown operation of the induction motor 100 in accordance with an exemplary implementation of the disclosure. Referring to FIG. 5, there is shown a flowchart of a method 500 which includes steps 502, 504, 506, 508 and 510.

[00125] At 502, the method 500 includes obtaining sensor data from a sensor component (e.g., sensor component 122) operatively connected to the induction motor 100. The sensor component 122 includes a plurality of sensors.

[00126] At 504, the method 500 includes processing the sensor data received from the sensor component 122 in real-time.

[00127] At 506, the method 500 includes computing a power factor value of the induction motor 100 using the processed sensor data.

[00128] At 508, the method 500 includes calculating a shutdown score based on the computed power factor value and the processed sensor data.

[00129] At 510, the method 500 includes initiating a shutdown sequence for the induction motor 100 when the shutdown score exceeds a pre-set threshold.

[00130] The present disclosure may be realized in hardware, or a combination of hardware and software. The present disclosure may be realized in a centralized fashion, in at least one computer system, or in a distributed fashion, where different elements may be spread across several interconnected computer systems. A computer system or other apparatus/devices adapted to carry out the methods described herein may be suited. A combination of hardware and software may be a general-purpose computer system with a computer program that, when loaded and executed on the computer system, may control the computer system such that it carries out the methods described herein. The present disclosure may be realized in hardware that comprises a portion of an integrated circuit that also performs other functions. The present disclosure may also be realized as a firmware which form part of the media rendering device.

[00131] The present disclosure may also be embedded in a computer program product, which includes all the features that enable the implementation of the methods described herein, and which when loaded and/or executed on a computer system may be configured to carry out these methods. Computer program, in the present context, means any expression, in any language, code or notation, of a set of instructions intended to cause a system with information processing capability to perform a particular function either directly, or after either or both of the following: a) conversion to another language, code or notation; b) reproduction in a different material form.

[00132] While the present disclosure is described with reference to certain implementations, it will be understood by those skilled in the art that various changes may be made, and equivalents may be substituted without departure from the scope of the present disclosure. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the present disclosure without departure from its scope.

Claims

CLAIMS I/WE CLAIM:

1. A system for controlling a shutdown operation of an induction motor, comprising: a sensor component including a plurality of sensors operatively connected to the induction motor, the sensor component configured to monitor at least one operational parameter of the induction motor; a control component interfaced with the sensor component, wherein the control component is configured to: receive and process sensor data from the sensor component in real-time; compute a power factor value of the induction motor using the processed sensor data; calculate a shutdown score based on the computed power factor value and the processed sensor data; and initiate a shutdown sequence for the induction motor when the shutdown score exceeds a pre-set threshold.

2. The system as claimed in claim 1, wherein the plurality of sensors include at least one of voltage sensors, current sensors, temperature sensors, vibration sensors, and speed sensors torque sensors, and acoustics sensors.

3. The system as claimed in claim 1, wherein the at least one operational parameter includes at least one of stator-rotor interaction, voltage, current, slip, torque and frequency supplied to the induction motor.

4. The system as claimed in claim 1, wherein the control component includes a machine learning module to adaptively adjust the shutdown score calculation based on historical data.

5. The system as claimed in claim 1 , further comprising a feedback mechanism within the control component configured to adjust future shutdown thresholds and parameters based on operational data collected during and after shutdown events.

6. The system as claimed in claim 1, wherein the shutdown sequence includes steps to gradually reduce speed and power consumption of the induction motor in a manner that minimizes wear and tear.

7. The system as claimed in claim 1, wherein the control component is configured to assign and dynamically adjust weights to different sensor data based on heuristic rules tuned based on correlations observed overtime.

8. The system as claimed in claim 7, wherein the control component is configured to normalize and weight the sensor data, for calculating the shutdown score.

9. An induction motor, comprising: a stator comprising a main winding (M) for generating a rotating magnetic field (RMF) upon providing a main AC power supply to the main winding (M) of the stator; and a rotor disposed to rotate relative to the main winding (M) of the stator due to the RMF, the stator further comprising an auxiliary winding (A), wherein rotation of the rotor induces an alternating EMF in the auxiliary winding (A) of the stator, wherein the alternating EMF produced in the auxiliary winding (A) is fed back to the main winding (M) of the stator throughout a complete rotation cycle of the rotor through an electronic control unit (ECU) coupled to the stator, the ECU comprising the system as claimed in claim 1.

10. An electric vehicle comprising the induction motor as claimed in claim 9.

11. A method for controlling a shutdown operation of an induction motor, comprising: obtaining sensor data from a sensor component operatively connected to the induction motor, the sensor component comprising a plurality of sensors; processing the sensor data received from the sensor component in real-time; computing a power factor value of the induction motor using the processed sensor data; calculating a shutdown score based on the computed power factor value and the processed sensor data; and initiating a shutdown sequence for the induction motor when the shutdown score exceeds a pre-set threshold.

12. The method as claimed in claim 11, wherein calculating the shutdown score comprises adaptively adjusting the shutdown score calculation based on historical data using a machine learning module.

13. The method as claimed in claim 11, further comprising adjusting future shutdown thresholds and parameters based on operational data collected during and after shutdown events using a feedback mechanism.

14. The method as claimed in claim 11, wherein initiating the shutdown sequence comprises initiating steps to gradually reduce speed and power consumption of the induction motor in a manner that minimizes wear and tear.

15. The method as claimed in claim 11, further comprising assigning and dynamically adjusting weights to different sensor data based on heuristic rules tuned based on correlations observed over time.

16. The method as claimed in claim 15, wherein assigning and dynamically adjusting weights to different sensor data comprises normalizing and weighting the sensor data, for calculating the shutdown score.