Mechanical design of 3 phase induction electric motor.
It is undeniable that the world's climate conditions are experiencing a significant quality decrease where the air around our homes, including Jakarta, are not feasible anymore where there are a lot of dangerous Particulate Matter 2.5 in the air that we breathe daily. Not only the air condition, the high demand for processed petroleum such as gasoline and diesel causes Indonesia to import where in 2018 there are 393,000 barrels per day. Of course, the budget spent to meet the fuel needs is not small, and will not decrease for the next few years, given that Indonesia's petroleum stock has also decreased. Based on these problems, Universitas Indonesia is committed to build an environmentally friendly transportation, called Electric Bus. This Electric Bus has prime mover in the form of a 3 phase induction motor. Author on this paper is doing the research to build an electric motor design used on The Bus, so that the motor can produce performance in accordance to the design specifications.
Multi-phase induction motor (MIM) drives with polephase modulation (PPM) is suitable for the Electric vehicle(EV) applications because of the reasons, like constant power operation with high efficiency over an extended speed-torque range and high reliability. By using Pole-Phase modulation, in this paper a 45-phase squirrel-cage induction motor (IM) drive is proposed with 1:3:5:9:15 speed ratios for EV applications. The proposed 45-phase IM drive with 90 stator slots is able to operate at five different pole-phase combinations, i.e., 45-phase 2-pole, 15-phase 6-pole, 9-phase 10-pole, 5-phase 18-pole and 3-phase 30-pole. The above five combinations make this MIM drive is suitable for EV applications, which eliminates the mechanical gear system in conventional EV. This can be helpful for saving the size and weight of the vehicle. This MIM drive offers the high torque for starting acceleration and gradient routes at low speeds and provides the high power for medium and high speed cruising, which is analogous to the typical five gear IC engine.
The problem of operating a three-phase induction motor connected to a single-phase supply system using two convertors is discussed. Special attention is focused on the starting torque and minimum unbalance requirements for different motor power ratings. A new approach is suggested here, concerning the calculation of the starting and running sizes of the convertors, to enable the motor to start under full load conditions with minimum unbalance factors. These sizes are also modelled as functions of the motor power, with a wide applicable range. A method of determining the switching instant of the first convertor sizes is also introduced and modelled. Numerical application of the proposal has been carried out on different induction motors to investigate its validity. The results prove a reasonable minimum unbalance factor of 5.8 per cent during normal running conditions. They also demonstrate that a sufficient starting torque is at least equal to the full load figure.
The method involves using block commutation and operating the electrical motor so that the commutation angle is less than 180 degrees and greater than 120 degrees. A natural number of successive states of equal duration is defined in each of which two or three of the phases (P1-P3) have a non-zero phase voltage. The state duration is derived from the motor speed and the number of poles. AN Independent claim is also included for the following: a brushless 3-phase electric motor.
A multi-phase electric motor including a housing, a stator mounted to the housing, a rotor rotatably mounted relative to the stator, and a position sensing system configured and disposed to output a signal representing a position of the rotor relative to the stator. The position sensing system includes a rotating member mounted relative to the rotor and a plurality of digital sensors mounted relative to the rotating member. At least two of the plurality of digital sensors are configured and disposed to generate a quadrature output signal. The plurality of digital sensors being configured and disposed to sense discrete portions of the rotating member to detect a position of the rotor relative to the stator.
The proposed method is based on extracting the magnitudes and phases of the high-frequency subband (HFSB) contents present in the d−q-axis components of the stator currents (id and iq) in an induction motor. The desired magnitudes and phases are extracted by processing id and iq using phaselet frames that are realized by a modulated filter bank. This filter bank is designed using six digital high-pass filters, whose coefficients are determined by biorthogonal phaselet basis functions. Extracted HFSB contents provide signature information that can offer accurate and fast detection of faults. The phaselet-based electric fault detection method has been made into a procedure for digital implementation. The performance of the proposed method is evaluated offline for collected stator currents from two different induction motor drives under different operating conditions. Offline test results show accurate, reliable, and fast detection of electric faults, with minor sensitivity.
Describes overvoltage caused by disconnecting a lot of motor-loads on a power distribution line with power-factor-correcting capacitors during a transmission line open-phase. The overvoltage phenomena are studied by a field test, a steady-state analysis and a transient analysis. Experimental results show that the line-to-line voltage on a 6.6 kV distribution line with an open-phase 22 kV transmission line amounts to 1.7 per unit. The overvoltages are caused by two types of resonance. One is the linear circuit resonance between the power-factor-correcting capacitors and the secondary side impedance of motors. The difference between positive components and negative ones of the impedance produces the resonance. The other is the nonlinear circuit resonance between the power-factor-correcting capacitors and the saturated reactances of a transformer.
This module consists of a uncontrolled rectifier circuit, buck converter circuit, and three phase inverter circuit as drive three phase induction motor. The module is a source of nets connected three phase rectifier circuit is governed by its three phase variac output from to 200 Vdc. Then the DC output rectifier circuit connected to the buck converter circuit, so that output DC use as input the inverter three phase which result voltage to 100 Vac. The inverter output voltage to run a three phase induction motor. Switching technique is used for triggering the inverter MOSFETs is PWM (Pulse Width Modulated) voltage switching mode with 180 conduction. The PWM signal generation is controlled through the microcontroller ATmega 8535.
This paper is modeling two type of 3 phases BLDC motors, one has Y-connection type and the other has independent type, and it shows simulation of them, compares its characteristics. As a result of simulation, phase voltage of independent 3 phase BLDC motor is higher than Y-connection three phase BLDC motor. When the stator resistance and inductance are stable, high phase voltage causes an increase in maximum phase current and an increases in it serially causes an increase of maximum torque. It is also found that the current pulsation of independent phase BLDC motor was decreased by controlling phase current of independent BLDC motor.
Under the low speed condition, a method of real-time tracking and estimation of rotor position based on PLL technology is proposed, which is used to solve the control system detection accuracy problem of permanent magnet synchronous motor (PMSM) for electric vehicles. The control principles of high frequency signal fluctuation are analyzed, and the mathematical model of three phases PMSM under rotor estimated synchronous rotating reference frame is established. The basic principles of phase locked loop (PLL) are analyzed. Based on phase locked loop, a rotor position estimation method is designed and analyzed. Finally, simulation model of sensorless control system is set up, and the simulation experiment is carried out. The simulation experiment results show that the sensorless control based on PLL can obtain the accurate rotor positions and the excellent control ability. Therefore, the rotor positions estimation method based on PLL is an ideal method for the sensorless control of electric vehicle drive motor.
The invention relates to an electric motor for power-converter operation with a selectable, multi-phase stator winding which is divided into similar, m-phased partial winding systems and is connected to a total of a.m. power-converter bridge branches connected in parallel on the d.c. side. It is possible to select the stator winding with relatively few switching contacts because the partial winding systems are galvanically separated and arranged in fixed star or polygonal array whereby, to change the winding over, at least one connection point of each partial system can be connected to a diametrically opposite connection point, from the phase position viewpoint, of another partial system via a separate switching component.
An electric motor system includes a motor housing and a stator core disposed within the motor housing . The stator core includes a back iron heat exchanger for passing fluid therethrough. A fluid inlet is disposed at a first portion a of the back iron heat exchanger that is at least partially in fluid communication with a liquid coolant source and is configured to accept a cooling mixture. A fluid outlet is disposed at a second portion of the back iron heat exchanger for outletting a gas coolant from the back iron heat exchanger such that liquid coolant is convertible to the gas coolant in the back iron heat exchanger by receiving energy from the stator core allowing the gas coolant exit through the outlet and thereby removing heat from the stator core .
A multi-phase electric motor including a housing, a stator mounted to the housing, a rotor rotatably mounted relative to the stator, and a position sensing system configured and disposed to output a signal representing a position of the rotor relative to the stator. The position sensing system includes a rotating member mounted relative to the rotor and a plurality of digital sensors mounted relative to the rotating member. At least two of the plurality of digital sensors are configured and disposed to generate a quadrature output signal. The plurality of digital sensors being configured and disposed to sense discrete portions of the rotating member to detect a position of the rotor relative to the stator.
A starting circuit for single phase electric motors including both split-phase and capacitor start motors includes a gate controlled solid state switch serially connected to the start winding of the motor. Rectified reference pulses from a pulse transformer are generated to turn on a first transistor to provide gating current for the solid state switch. Initially, when the motor is energized at zero rpm, the pulses are received at the switch after the start winding current passes through the zero current level to gate the switch to conduct each half cycle and energize the start winding however as the motor speeds up, the pulses are received earlier and earlier relative to the start winding current zero cross over until at a selected speed the pulses are received at the switch prior to the start winding current zero cross over with the result that the switch is no longer gated conductive. When this occurs, the voltage across the switch goes high.
The method for controlling a voltage/frequency converter controlled single-phase or polyphase electric motor evaluates the phase shifting between the EMF and BEMF by way of the deviation between the zero crossing of the phase current and the voltage produced by the intrinsic induction and readjusts the frequency of the converter accordingly. The measurement of the intrinsic induction is effected in the zero crossing of the current courses of the associated phase, wherein during the measurement the phase is separated from the supply network.
An electric motor control circuit, especially for a split phase motor, in which a positive temperature coefficient resistor is interposed in the starting winding circuit to substantially remove the starting winding from the circuit after the motor has started while a temperature sensitive switch is provided in series with the motor to deenergize the motor when it is overloaded. The positive temperature coefficient resistor element has a temperature sensitive element associated therewith which prevents the temperature sensitive switch from activating to a closed position from an open position whenever the resistor element is above a predetermined temperature.
A small two-phase motor having first and second field coils which each cooperate with a long, thin cylindrical rotor. The rotor is provided with only a single pair of nonsalient rotor poles and has a length to diameter ratio which advantageously is at least about 2.5. A stator pole piece assembly is in magnetic flux relationship with the rotor and includes first and second sets of salient stator poles which respectively cooperate with the first and second field coils. There are only two salient stator poles in each set, and the stator poles are angularly spaced apart by approximately ninety electrical degrees. In some embodiments one of the stator poles in the first set and one of the stator poles in the second set extend in opposite directions parallel to the rotor axis from a single tubular member which forms a part of the pole piece assembly.
A control method for a brushless, three-phase DC motor. A voltage induced by rotation of a rotor may be sampled at a first expected zero crossing value to produce a first sampled voltage value. An average of a plurality of sampled voltage values, including voltage values sampled at a plurality of prior expected zero crossing values and the first sampled voltage value, may be calculated. The first sampled voltage value may be subtracted from the calculated average to produce a delta zero crossing error. A pulse-width modulation duty cycle may be adjusted based on the delta zero crossing error. The pulse-width modulation duty cycle may be used to control a rotational velocity of the rotor.
In addition to basic characteristics such as a small size, light weight and easy maintenance, the electric vehicle (EV) motor is required to possess characteristics which allow for the production of a high torque at a low speed region and to realize a wide range of constant power operation at a high speed region.In an attempt to further improve the constant power operation properties of the induction motor (IM), this paper proposes a six-phase pole change IM (six-phase PCIM). The six-phase PCIM further expands the constant power operation range without increasing the volume and current of IM.To clarify the basic principle and the torque characteristics of the six-phase PCIM, first, its winding method and distribution of mmf will be examined. Next, by establishing a performance calculation method based on quasi-sinusoidal wave method, the feasibility of a highly precise performance calculation sufficient for actual use will be demonstrated. Furthermore, by clarifying the maximum torque characteristics through experiment.
Steep-fronted voltage transients, generated by prestriking conditions in circuit breakers and contactors when closing, produce severe interturn insulation stresses in machine windings. A computer program simulating the production of prestriking transients is described. The simulation is based on a full three-phase system representation, including busbars, switching device, cable and motor winding. The complex interaction between the system and the switching device, and also the interaction between the three poles of the switching device, are fully taken into account. A solution method based on the Fourier transform and using a combination of voltage and current generators to simulate switching actions is used in the calculations.
A five–phase in–wheel fault–tolerant interior permanent–magnet (FT–IPM) motor incorporates the merits of high efficiency, high power density and high reliability, suitable for Electric Vehicles (EVs). A new remedial Neural Networks Inverse (NNI) control strategy is proposed to attain the post–fault operation. In this scheme, the NN is used to approximate the inverse model of the FT–IPM motor. With this NNI system and the original motor drive combined, a pseudo–linear compound system can be obtained. The simulation demonstrates that the proposed control strategy leads to excellent control performance at the faulty mode and offers good robustness against load disturbance.
An electrical circuit protects a direct current electric motor from overload. The circuit has a permanent magnet stator, a rotor taking the motive current via a commutator, a recovery diode, and a precision resistor. The precision resistor is in series with the recovery diode. A distribution voltage (Uv) is applied between the recovery diode and the precision resistor , via a power switch between one of the power switch electrodes and a nodal point . The power switch control electrode is connected to a comparator output . The comparator first input is connected to the nodal point , and a second input is linked to a threshold value transmitter. The link between the irst electrode , distribution voltage and nodal point is interrupted above a pre-determined threshold value, and is restored when the voltage has fallen below a lower threshold value.
Described herein is a throttle valve for an internal-combustion engine; the throttle valve is provided with: a three-phase brushless electric motor having three stator windings and three angular-position sensors designed to determine the angular position of a rotor of the electric motor ; a valve seat ; a turnable disk element or butterfly , which engages the valve seat and is mounted on a shaft so that it can rotate about an axis of rotation to turn between an opening position and a closing position of the valve seat under the thrust of the electric motor ; a gear transmission to connect the electric motor to the shaft of the disk element ; and an electronic control unit designed to drive the electric motor according to a feedback control logic using as feedback quantity the angular position of the disk element about the axis of rotation, measured by means of the three angular-position sensors integrated in the electric motor .
A method is provided for detecting an insufficient or missing phase current in a permanent magnet synchronous motor, and includes determining a composite vector position of a combined three-phase phase current with respect to a stationary portion of the motor, and assigning a sector to the position. The method includes comparing the phase current to a calibrated threshold current corresponding to the sector, and executing a response when the absolute value is less than the threshold. A vehicle includes an energy storage device (ESD), a motor/generator configured as a permanent magnet synchronous motor, a voltage inverter, and a bus for conducting DC current from the ESD to the inverter. A controller detects an insufficient phase current, determines a current vector position of the three-phase AC, assigns a sector to the position, and executes a response when an absolute value of the phase current is less than a calibrated threshold.
A permanent split capacitor electric motor is constructed by using existing components of a known shaded pole motor design to reduce engineering, tooling, inventory and other manufacturing costs of the new motor and, potentially, the known design through economics of scale. The alterations to the known motor principally involve different winding circuits and the addition of a capacitor. The new motor can be reversed with a single switch circuit.
