77results about How to "Reduce harmonic loss" patented technology

The invention relates to a permanent magnet synchronous motor (PMSM) AC servo system, which is composed of a DSP control panel, a rotary transformer, a main power circuit and a conditioning and protecting circuit, a motor body consists of an armature winding and a permanent magnet core rotor, wherein the motor is excited by a permanent magnet, and the DSP is used for realizing an field-orientated control algorithm, communication, sampling calculation of current and configuration output of a drive; the output of the rotary transformer enables data to be transmitted to the DSP via four-path DA transform chips and SPI of the DSP or multi-channel buffering; the DSP outputs pulse width modulation, is connected with voltage signals output by a current regulator, and is connected with a PWM1-PWM3 drive inverter which can convert the voltage signals into three-phase switch signals by CLARK inverse transformation, and the inverter outputs to the armature winding so as to control the armature winding of the motor to generate a rotary round magnetic field; and the main power circuit is composed of a direct current detection circuit with controllable rectification, an inverter, a current detection circuit, an overvoltage discharging circuit, a protection circuit and a driving circuit. The invention adopts the field-orientated control algorithm which can control the torque, speed and position state of the motor in real time and has good control performance.

The invention provides a magnetic field modulating type concentric magnetic gear transmission device in a Halbach magnet structure, which comprises a shell, an outer rotor and an inner rotor, whereinthe outer rotor and the inner rotor are installed in an inner cavity of the shell and are in a cantilever type; the inner rotor comprises an inner rotor iron core and a permanent magnet, which are installed on an output shaft of the inner rotor; the outer rotor comprises an outer rotor iron core and a permanent magnet, which are installed on an output shaft of the outer rotor; a magnetic modulation ring is arranged between the permanent magnet of the inner rotor and the permanent magnet of the outer rotor; and the magnetic modulation ring comprises an iron core block and is fixed on an end plate of the shell. The magnetic gear transmission device comprises two layers of air gaps, wherein an inner-layer air gap is formed between the inner rotor and the magnetic modulation ring, and an outer-layer air gap is formed between the outer rotor and the magnetic modulation ring. The magnet structure uses a Halbach array to replace the conventional radial structure, thereby improving the magnetic density distribution of the air gaps of the magnetic gear transmission device. Because the magnetic density of the air gaps approaches to sinusoidal distribution, the detent torque of the magnetic gear transmission device in the structure is greatly reduced, thereby decreasing the vibration and noise of the magnetic gear transmission device and improving the running efficiency.

The invention provides an optimization control method based on selective harmonic elimination pulse width modulation (SHEPWM). The optimization control method based on the SHEPWM comprises the following steps: writing amplitude expressions of fundamental waves and controlled harmonic waves of all times in an arraying mode, confirming amplitude of the fundamental waves and the controlled harmonic waves of all times, and obtaining a switch angle. The optimization control method is combined with characteristics of amplitude frequency of a filter, obtains the most advantageous size value of the amplitude of the controlled harmonic waves by optimizing an objective function, improves the harmonic wave distribution condition of an SHEPWM wave form, reduces amplitude of surplus harmonic wave, enables a total harmonic content to reduce, and even removes the big surplus harmonic waves. Small amplitude changes of a controlled harmonic wave component can cause great influence on harmonic wave distribution of output voltage, and suitable changes can reduce amplitude of surplus harmonic wave components of a traditional SHEPWM method.

The invention discloses an environment-friendly and energy-saving DC power station. The DC power station comprises an input AC voltage sampling circuit, an input AC current sampling circuit, a load voltage regulator, a rectiformer, a commutator, a controller, a filter and power compensation device, an output DC voltage sampling circuit, and an output DC current sampling circuit, the output of the input AC voltage sampling circuit and the input AC current sampling circuit is connected with the controller, the load voltage regulator is serially connected between the AC input power supply and the input end of the rectiformer, the secondary lateral low voltage winding of the rectiformer is connected with the input end of the commutator, the secondary lateral medium voltage winding of the rectiformer is connected with the filter and power compensation device, the output of the output DC voltage sampling circuit and the output DC current sampling circuit is connected with the controller, the control output of the controller is respectively connected with the commutator and the control end of the filter and power compensation device. The invention can realize the constant control of the high power factors and good harmonic wave shield as well as can improve the running efficiency of the system.

The invention discloses an induction and phase-shifting rectifier transformer. The transformer is in a three-pole iron core structure, wherein each iron core pole is wound by four windings which include an AC line side winding, a filter winding, a valve side star-connected winding and a valve side delta-connected winding; the line side winding is arranged in the innermost layer of each iron core pole; the filter winding is arranged on the external layer of the line side winding; and the valve side star-connected winding and the valve side delta-connected winding are arranged on the external layer of the filter winding and respectively connected with a group of six-pulse rectifiers. The invention can counteract harmonic magnetomotive force generated by 5, 7, 11, 13, 17 and 19 characteristic harmonic currents of the transformer, thereby ensuring that the current in the line side winding is basically in a sine wave mode and greatly reducing the harmonic loss of the line side winding and other AC line side power equipment.

The invention relates to a user side energy-saving power-saving management system. The user side energy-saving power-saving management system comprises a server host, a communication network, a wireless transmission part, a wired transmission part, and various metering points. The server host is connected with the wireless transmission part and the wired transmission part by a communication network. The wireless transmission part and the wired transmission part are respectively connected with the various metering points. An electric energy on-line module, a power utilization analysis module, an auxiliary deciding module, an ordered power utilization module, and an energy-saving diagnosis consultation service module are embedded in the server host. Compared with the prior art, an object of realizing enterprise intelligent energy efficiency management is achieved, and power utilization costs are saved, and power utilization quality is improved.

The invention discloses an amplification module suitable for a class F or inverse class F power amplifier. The amplification module is applied to the class F power amplifier or the inverse class F power amplifier. The amplification module comprises a transistor, a resonator module for realizing harmonic wave matching required by the class F or inverse class F power amplifier, a base, a signal input end and a signal output end. The resonator module comprises a parallel resonator group and a series resonator group. The parallel resonator group comprises a first resonance module and a second resonance module. The series resonator group comprises a third resonance module and a fourth resonance module. Each resonance module comprises at least one film bulk acoustic resonator. Through adoption of the amplification module, the size of the class F power amplifier or the inverse class F power amplifier is reduced, harmonic loss is lowered, the efficiency of the power amplifier is improved, mutual interference of a harmonic wave matching network and a fundamental wave matching network is reduced, and the design of the class F power amplifier or the inverse class F power amplifier is easier.

The invention provides a rotor and a permanent magnet motor. The rotor includes a rotor core and a permanent magnet which is arranged in a mounting groove in the rotor core, wherein the permanent magnet is provide with a first end and a second end; the first end is far away from a center shaft of the rotor core; the second end approaches to the center shaft of the rotor core; and from the first end to the second end, the thickness of the permanent magnet is not consistent in the magnetization direction. The scheme of the rotor and the permanent magnet motor can solve the problem that the rotor of an existing permanent magnet motor is relatively high in the air-gap flux density harmonic wave content and is relatively small in the reluctance torque.

The invention is a double-winding two-phase brushless direct-current motor, which relates to a motor, which includes a stator part, a rotor part and a controller. The number of magnetic poles of the rotor is two poles, the number of slots of the stator is four slots, and the working mode of the stator winding is double winding. The current phase difference of the two-phase windings is 90 degrees electrical angle, there is no dead point where the torque is zero, and there is no need to adopt an asymmetrical air gap structure. No cogging torque. Compared with ordinary miniature single-phase brushless DC fans, the magnetic field distortion in the air gap is small, the stator magnetomotive force harmonic loss is small, the output torque is large, and the motor efficiency is high. The controller adopts two ordinary miniature single-phase brushless DC fan controller chips, and uses an external power switch tube to expand the current driving capability, which has the advantage of low cost. If the number of rotor magnetic poles is two, the angle of the rotor magnetic pole pole arc is large, and the Hall element can track the magnetic pole state of the permanent magnet of the rotor with high precision, and it is not easy to cause out-of-control phenomena.

The invention relates to the technical field of high-voltage permanent magnet synchronous motors, and discloses a rotor permanent magnet series distribution-linked high-voltage permanent magnet synchronous motor, which comprises a motor shell, a stopper is fixedly connected with the motor shell, a first fixing seat is fixedly connected with stopper, a second fixing seat is fixedly arranged on theinner wall on the right side of the motor shell. The rotor permanent magnet series distribution-linked high-voltage permanent magnet synchronous motor can make the waveform of the counter electromotive force achieve the best effect as long as the design of each segment length is appropriate, the useless harmonic generated by the stator is minimized, the harmonic loss is minimized, the motor achieves high efficiency, the manufacturability is good, the rotor punching die is most simple, and each magnetic steel is easy to install due to small volume, and the design level and the process level ofthe high-voltage permanent magnet motor become reliable and efficient, so that the design of this type of motor becomes feasible, and meanwhile, the motor can be applied to various complex occasions.

The invention relates to the technical field of electromagnetic power, and provides a double-cage rotor magnetic pump, which comprises a motor, a pump body, a shell, an input shaft and an output shaft, wherein the input shaft is rotatably arranged at one side of the shell, and the first end of the input shaft is arranged in the shell; the second end of the input shaft is arranged outside the shell, and the output shaft is rotatably arranged on the pump body; the first end of the output shaft is arranged in the shell, and the second end of the output shaft is arranged in the pump body; a cup-shaped sleeve is arranged on the first end of the input shaft, and an annular outer magnetic rotor core is arranged on the inner side edge of the cup-shaped sleeve; an annular shaft sleeve is arranged at the first end of the output shaft, and an annular inner rotor core is arranged outside the annular shaft sleeve; an outer magnetic rotor magnet ring is arranged on the inner wall of the annular outer magnetic rotor core, and upper and lower mouse cages are arranged on the annular inner rotor core; and the inner rotor core and the upper and lower mouse cages form an inner rotor, and an annular gap is formed between the outer magnetic rotor magnet ring and the inner rotor. With the technical scheme provided by the invention, the air-gap magnetic flux density forms a sine waveform, and the harmonic loss of the core is reduced.

The invention discloses a three-phase dry transformer for a motor train unit auxiliary system, and the transformer comprises an iron core and a main coil arranged on the periphery of the iron core ina winding mode; the iron core comprises a main iron core body and an auxiliary iron core body, the main coil comprises a low-voltage winding and a high-voltage winding, and the main iron core body comprises a main iron core column and a main iron yoke connected with the main iron core column. The auxiliary iron core comprises an auxiliary iron core column and an auxiliary iron yoke connected withthe auxiliary iron core column, the low-voltage wire is wound on the main iron core column to form a low-voltage winding, the high-voltage wire drives the auxiliary iron core column to be wound on thelow-voltage winding at the same time to form a high-voltage winding, and the high-voltage winding and the low-voltage winding comprise a plurality of transposition copper wires which are wound in parallel; and the lengths of the transposed copper conductors which are arranged in parallel are the same. By means of the mode, the three-phase dry-type transformer for the auxiliary system of the motortrain unit can reduce the thickness of a single wire, meanwhile, the chance that each wire is located in a leakage magnetic field is equal, circulation between the wires is reduced, harmonic loss isreduced, and the overall harmonic loss can be reduced by 80%.

The invention provides a motor frequency conversion control method and apparatus, and relates to the technical field of frequency conversion of a motor; and not influenced by nonlinear parameters of the motor, high robustness is achieved. According to the main technical scheme, the motor frequency conversion control method comprises the steps of obtaining the actual position of a voltage vector ofthe motor; obtaining the instruction position of the voltage vector of the motor; and adjusting the motor drive switching frequency according to deviation between the actual position of the voltage vector and the instruction position of the voltage vector. The motor frequency conversion control method is mainly used for realizing synchronous frequency conversion control in the dynamic changing process of the motor.

The invention discloses a box-type high-speed motor which is mainly composed of a box-type motor stator, a bearing installed on a box-type motor stator base and a motor rotor supported by the bearing,a cooler is located at the top of the box-type motor, and the motor rotor is of a solid rotor structure and is provided with balance areas at the two ends of a rotor body. The motor rotor is also provided with a balance area in the center of the rotor body. The box-type high-speed motor is compact in structure and reliable in operation, and is suitable for higher-rotating-speed working conditions.