Abstract:
A driver (DR) for a brushless motor comprises at least three outputs (O U , O V , O W ) for supplying coils (U, V, W) of the motor. The driver (DR) has a first and a second output (O U , O V ) for providing a first and a second supply signal (S U , S V ) respectively. During a first commutation state (CS1) the first and the second supply signal (S U , S V ) respectively have a first and a second average voltage (V1, V2). During a second commutation state (CS2) succeeding the first commutation state (CS1) the first and the second supply signal (S U ,S V ) respectively have a third and a fourth average voltage (V3, V4). The second and the third average voltage (V2, V3) having a value intermediate the first average voltage (V1) and the fourth average voltage (V4).
Abstract translation:用于无刷电动机的驱动器(DR)包括至少三个输出(O U SUB>,O V SUB>,O W SUB>), ,V,W)。 驱动器(DR)具有用于提供第一和第二电源信号(S U SUB>)的第一和第二输出(O SUB>,S V SUB>)。 在第一换向状态(CS1)期间,第一和第二供电信号(S ,S V SUB>)分别具有第一和第二平均电压(V1,V2) 。 在第一换向状态(CS1)之后的第二换向状态(CS2)期间,第一和第二供电信号(S U SUB>,S V SUB>)分别具有第三换向状态 第四平均电压(V3,V4)。 第二和第三平均电压(V2,V3)具有在第一平均电压(V1)和第四平均电压(V4)之间的值。
Abstract:
A power tool having an electronically commutated DC motor capable of providing various operating modes ranging from a maximum efficiency operating mode to a maximum power operating mode. The motor has a rotor having permanent magnets mounted in recesses in a back iron of the rotor. In one embodiment the motor has three phase windings, each having at least a pair of coils. The phase windings are connected in either a delta or a wye configuration via electromechancial or electronic switching components, or a combination of both, by a controller within the tool. The coils in each phase winding can also be switched between series and parallel configurations to configure the motor to provide its various operating modes. In one embodiment a dual wound motor is disclosed that has its phase coils dynamically or statically switchable between series and parallel configurations.
Abstract:
Schatzwerte (i d (EST) , i q (EST) ) von Motorstromen einer Synchronmaschine werden in einem mit einem Rotor umlaufenden Koordinatensystems mittels eines Beobachters ermittelt und zwar abhangig von Sollwerten (u d , u q ) elektrischer Spannungen der Synchronmaschine (PMSM) in dem mit dem Rotor umlaufenden Koordinatensystem.
Abstract:
The present invention discloses a method for measuring the operating state of a synchronous motor using composite power angle meter.1t includes the following steps: a, obtaining all kinds of signals of the synchronous motor as well as the system; b, converting the electric signals described above into digital signals by data collection part in the composite power angle meter and inputting all the digital signals to a host computer; c, inputting related parameters or commands to the host computer by using the keyboard and mouse; d, the host computer calculating the motor's related data according to a program, obtaining the coordinates of related points as well as related data, and inputting the results to a image displaying program; e, by using the coordinates of main points and the calculated results, the host computer displaying graphs on the display by the processing of the image displaying program, the graphs showing dynamic composite power angle and compound leakage magnetism in the motor's end which change along with the change in the motor's parameters. The method supplied by the present invention can reflect the operating state of the synchronous motor directly from electric and mechanic aspects, and reflect the situation of the compound leakage magnetism in the synchronous motor's end.
Abstract:
Reactive power (VAR) consumption in a power plant or facility having synchronous machines is adaptively controlled in an automated manner. Electrical parameters of the plant are dynamically monitored during plant operation, and the overall plant power system is brought to an optimum operating point under control of a microprocessor-based power measurement system. The microprocessor-based power measurement system adaptively changes the excitation system of synchronous machines in the plant based on results of monitoring. The excitation systems of the synchronous machines may be adjusted to be constant bus voltage, constant reactive power, or constant power factor, according to optimum system performance requirements. The power measurement system also assists in avoiding problems in voltage regulation during increased load demand conditions, such as when starting large electrical motors or energizing large transformers in the system.
Abstract:
A system and method for assembling machines using multiple, structurally equivalent components. The characteristics of each component are tested. The tested components are sorted into component classes using the test information. Individual components are selected from the classes and combined in a manner that, when combined, will provide desired price/performance characteristics in the machine. Machines with improved price/performance characteristics may be assembled without requiring change to the quality of the components, or the manner in which the components are manufactured.
Abstract:
Reconfiguration of stator winding sections of each phase of a multiphase motor is controlled for successive ranges of speed during which the motor can be expected to operate to obtain optimum operating efficiency throughout the entire operating range. All winding sections for a stator element are energized throughout the motor operating speed range but connected, through appropriate switches, in different circuit configurations for respective portions of the speed range. The switches are activated by a controller in response to a sensed motor speed signal. The reconfiguration of stator winding sections may be incorporated within a motor control system that is adaptive to control various motor parameters in response to sensed conditions as well as user input commands.
Abstract:
This invention relates to a variable speed drive with synchronous AC motor. In the disclosed embodiment, a variable speed drive operates in three modes: a first predetermined mode, in which a function (e.g., trapezoidal current waveform) controls operation at low motor speeds; a transitional mode, in which a transition function is applied to anticipate transitions of the first function, thus causing a smoothing of transitions at higher speeds; and a second predetermined (e.g., sinusoidal or smoothly-varying current) waveform at high speeds. This allows for the reduction in required rotor position sensor resolution as compared to conventional synchronous variable speed drives, resulting in cost savings in the sensor device and associated wiring. Additionally, it is quieter and more efficient operation at high speed as compared to conventional trapezoidal-current/DC-brushless motor drives.
Abstract:
The invention concerns an apparatus (1) to assist a patient respiration by delivering air to a patient through a mask, said mask being designed to be connected on one first extremity of a tube, said apparatus comprising: - a control unit (2) to adjust the pressure delivered by the blower (4) of said apparatus, - a first pressure sensor (6) for sensing the pressure PM at said first tube extremity and being connected to said control unit, and - a second pressure sensor (8) for sensing the pressure PB at the air output of said blower and being connected to said control unit; in order that, when a tube is connected to said mask and connected to said apparatus on its said second extremity, the air flowing from the apparatus to the mask, said control unit is able to calculate the airflow at said second extremity of the tube from said pressures PM and PB and from the airflow resistance coefficient K t of said tube.
Abstract:
A commutation and velocity control system of a brushless DC motor receives a velocity command signal and provides command signals to drive the brushless DC motor. The system includes a summer that receives the velocity command signal and a velocity feedback signal and provides a velocity error signal indicative of the difference. A velocity loop compensator receives said velocity error signal and provides a compensated velocity error signal. A magnitude sensing circuit senses the magnitude of said compensated velocity error signal and provides a velocity magnitude signal indicative thereof. A polarity sensing circuit senses the polarity of the said compensated velocity error and provides a velocity polarity signal indicative thereof. The system also includes an integrated circuit having: (i) a velocity calculation circuit that receives a first sampled digitized signal indicative of resolver position at a first time and a second sampled digitized signal indicative of resolver position at a second time, and determines velocity based upon the difference between said first and second sampled digitized signals and provides a sensed digitized velocity signal indicative thereof; (ii) a commutation logic circuit that receives said first sampled digitized signal, said velocity magnitude signal and said velocity polarity signal, and provides said command signal; and (iii) a counter that receives a signal indicative of said sensed digitized velocity signal and provides a pulse width modulated output signal indicative thereof. A filter receives said pulse width modulated output signal and generates said velocity feedback signal.