2583 results about "Induction motor" patented technology

A multi-motor drive in which the resonance existing between one or more output filter capacitors of a current source inverter and an a.c. induction motor is reduced. The inverter features a switching pattern generator which controls the power switches of the inverter based on a reference current. A control loop, connected to the switching pattern generator, measures the load current or voltage and generates a nominal reference current based on an error therein; determines a damping current based on the voltage at the terminal; and determines the reference current supplied to the switching pattern generator by subtracting the damping current from the nominal reference current. The invention essentially simulates the use of a physical damping resistor connected in parallel with each output filter capacitor, but without the corresponding energy loss. This form of active damping control is also applied to a resonance mode existing between the input filter capacitors of a PWM-based rectifier and the system inductance of a power source.

Control of an induction motor is carried out to limit damaging arcing stress and mechanical stresses placed on the control contactor assembly and the induction motor resulting from the simultaneous or synchronous breaking and making of contactors employed to connect the windings of the motor to a power supply. Asynchronously connecting the windings to the power supply via the asynchronous or non-simultaneous closing of the contactors of a modular contactor assembly reduces the potentially damaging transient current, the associated torque oscillations, and mechanical stresses. The present invention is particularly applicable to delta motors that are started with its windings in a star or wye configuration followed by the reconnection of the windings in a delta configuration when the motor is at normal running speed.

The drive for an a.c. induction motor features a rectifier for converting alternating current into direct current and a current source inverter for converting direct current into alternating current supplied to a motor. A d.c. link choke interconnects the rectifier and the inverter. The inverter includes a first control loop which provides a desired or command d.c. link choke current to a second control loop responsible for the rectifier. For the purposes of the second control loop the actual d.c. link choke current and an input voltage of the inverter are detected. The difference or error between the desired and actual d.c. choke currents are minimized by a compensator. The output of the compensator is added to the detected inverter input voltage, and the sum is fed to a switching pattern generator which controls the switches in the rectifier. In this manner the feedback of the inverter input voltage is decoupled from the compensator responsible for the d.c. link choke current. This makes the parameters of the second control loop substantially independent of the load, thereby enhancing the ease with which the control loop may be tuned and hence the stability of the drive.

An indoor or outdoor induction cook top with a heat management system is disclosed. The cook top controls heat generated by various components, including the electronic controller, mechanical controls, and the induction generators. The heat management system provides precise temperature control and an efficient way of removing heat from the cooktop. The cook top construction provides the ability to incorporate a smooth ceramic glass cook top and a number of induction hobs in multiple arrangements. The cook top also features a reduction in the number of components, the efficient removal of generated heat, the reduction of noise, an increase in performance and a barrier airflow director. Consequently, the cook top may be installed in a countertop without the need for venting above the counter.

The invention relates to a online testing process for shorted fault of asynchronous motor's stator winding, which is belong to Detecting Technology. It was designed to solve the detecting problem of stator winding. The project is that it figures out the voltage and current of negative sequence and positive sequence of the stator winding by collecting three-phase stator voltage, instantaneous-current signal. Then using of normal motor sample reference document estimated the filter value of the stator negative sequence, figured out the stator negative sequence current fault component. And then base on the threshold of the stator negative sequence current fault component educe failure exponent. Finally according to the index judge whether to exist short circuit failure or not. This invention also gave corresponding detection device. Not only can high sensitivity, high reliability and on-line measurement asynchronous motor stator windings at the beginning of the early short circuit fault, but also can judge short circuit phase. This can effectively ensure the asynchronous motor operating safely.

A power controller for applying power to an induction motor or similar AC load has a variable drive circuit for staring and switching a portion of the AC input line power. In one mode, the input line power is fed straight through to the load. In another mode, the AC waveform is reshaped to improve the power factor or to boost its RMS value, e.g., for brownout protection. In a further mode the output power can be provided at a different frequency from the input line power. Vector control increases efficiency through power optimization, with sensing of load requirements. Sensing of regeneration pulses at the commencement of a half cycle can be employed for direct sensing of motor speed or load.

An intelligent treadmill is described with modifications to existing treadmills, and associated methodology. The invention allows the conveyor belt automatically keeps track of and fixes the user's position dynamically with respect to a stationery reference point of the treadmill by adjusting its own speed free hands. Two position measurement techniques and their corresponding belt speed control algorithms are described. Other features of the invention allow users to perceive in real time how their surroundings would be changing by means of video, incline of platform, fan speed, sound and illumination as if they were in fact running in the natural environment. Real time positions of the runner and his partners on other treadmills with respect to a chosen track are displayed. The invention also utilizes a vectored controlled 2/3-phase AC induction motor or a BLDC motor to drive the conveyor belt for energy efficiency and fast response.

The invention discloses a micro-grid system voltage stability control method based on robust control. The control structure of an intelligent micro-grid system is composed of a system control layer, a concentrated control layer and a local control layer, and energy optimization and voltage and frequency stability control of the micro-grid system are realized through multi-layer coordination control. According to the micro-grid system voltage stability control method based on robust control, a comprehensive load module of an induction motor is established, wherein dynamic loads are connected with static loads in parallel. On the premise that the constraint conditions of system performance and robust stability are met, a micro-grid voltage stability robust controller is designed by the adoption of a method of solving the problem of mixed sensitivity so as to improve the micro-grid voltage stability. The micro-grid system voltage stability control method based on robust control can be adapted to wide-range change of load parameters, has high robustness for the situations that due to the factors such as changes of running conditions, influences of external environment and frequency switching of the loads, perturbation is generated in model parameters of a micro-grid and uncertainty exists in the topologic part and the unmolded part and can better restrain parameter drift and noise interference, and meanwhile, the controller is simple in structure and easy to realize.

A method of providing ride-through capability in a chiller/refrigeration system employs a variable speed drive with an active converter stage, a DC link stage and an inverter stage for providing variable frequency and voltage to power at least one motor. An induction motor is coupled to the output of the inverter stage for driving a compressor in the chiller/refrigeration system. The ride-through method comprises operating the active converter to regulate the DC link voltage of the DC link stage to a predetermined voltage level until the current through the active converter equals a predetermined current limit, then transferring regulation of the DC link to the inverter upon reaching the current limit of the converter. The compressor is unloaded, and the power flow through the inverter is reversed to maintain the voltage level of the DC link stage. Pre-rotation vanes, slide valve, or check valve are used to unload the compressor.

A method of providing ride-through capability in a chiller/refrigeration system employs a variable speed drive with an active converter stage, a DC link stage and an inverter stage for providing variable frequency and voltage to power at least one motor. An induction motor is coupled to the output of the inverter stage for driving a compressor in the chiller/refrigeration system. The ride-through method comprises operating the active converter to regulate the DC link voltage of the DC link stage to a predetermined voltage level until the current through the active converter equals a predetermined current limit, then transferring regulation of the DC link to the inverter upon reaching the current limit of the converter. The compressor is unloaded, and the power flow through the inverter is reversed to maintain the voltage level of the DC link stage.

This invention is a methods and devices for detecting the fault of a cage rotor, which belongs to testing technology and for the settlement of broken rotor on the early detection of fault issue. Its technical program: through the acquisition of the stator transient current (is) continuously to do Fourier transform, receiving fundamental wave namely reference signal uS. Do adaptive filtering based the reference signal uS and the frequency f1 for the stator current transient signal. And then filter the output signal eT to do continuous the Fourier transform, identified (1 +- 2s) f1-frequency component and the amplitude of the fundamental components ratio as a failure features, the final determining fault index depending on fault detection threshold index and judge of Broken Bars, This invention can high sensitivity, high reliability and on-line detect the early induction motor of Broken Bars.

An auxiliary electric drive assembly includes an alternating current induction motor, planetary speed reduction gearing and a differential. The differential may be either active or passive. The auxiliary drive system is utilized as the front axle in a rear wheel drive vehicle and the rear axle in a front wheel drive vehicle. Elimination of many of the components in a conventional four wheel drive system such as the transfer case and hybrid gears improves the overall efficiency and fuel economy of a vehicle so equipped.

This disclosure relates to transient energy systems for supplying power to a load substantially instantaneously on demand. Transient energy systems may include a flywheel coupled the rotor of an induction motor generator. One embodiment of the disclosure refers to systems and methods for reducing loads on a bearing in a transient energy system. In another embodiment, the disclosure refers to an induction motor generator that is optimized for high power transient power generation, yet low power motor operation. Yet another embodiment of the disclosure refers to using a flywheel as a drag pump to cool components of a transient energy system. In yet another embodiment, a slip control scheme is discussed for regulating a DC bus. In yet a further embodiment of the disclosure a method is provided for reducing unnecessary turbine starts by making turbine start a function of the rotational velocity of a flywheel.

The invention discloses an induction method of a three-dimensional (3D) online induction system for mechanical equipment dismounting. The induction system comprise an eyeglass-type augmented reality helmet, a hand position tracking device and a computer, wherein the augmented reality helmet is provided with two display screens and two cameras; and wireless communication can be realized among the augmented reality helmet, the hand position tracking device and the computer. An induction method for realizing the three-dimensional online induction system for mechanical equipment dismounting comprises the following steps of: 1, transforming a virtual assembly model; 2, initializing the induction system; 3, recognizing the dismounting purpose; 4, generating induction information; 5, overlapping the induction information; and 6, repeating the steps 3-5 until the online product induction is finished. The method disclosed by the invention has the characteristics of accurate induction information, strong universal capability and convenience in carrying, and can be used for realizing the 3D online induction driven by requirements of operators, current situations of tasks and dismounting history and realizing the integration of product 3D design and dismounting induction.

There is provided an electric motor having a flat form factor. The electric motor has a rotor with a shaft attached thereto. The rotor further includes a plurality of teeth disposed thereon. The motor further includes a stator having an axial length. A plurality of teeth are disposed on the stator such that a gap is defined between the teeth of the stator and the teeth of the rotor. The motor further includes a plurality of copper windings disposed around each of the teeth of stator. Each of the windings has a length of end copper equal to about twice the axial length of the stator. In this regard, the end of the wire is greater than the width of the stator such that the form factor of the motor can be flattened.