CPC Definition - Subclass H02P
This place covers:
Arrangements for
- starting,
- regulating,
- electronically commutating,
- braking,
or otherwise controlling:
- motors,
- generators,
- dynamo-electric converters, clutches, brakes, gears,
- transformers,
This place does not cover:
Arrangements for merely turning on an electric motor to drive a machine or device, e.g.: vacuum cleaner, vehicle starter motor | |
Arrangements for controlling electric generators for charging batteries | |
Arrangements for starting, regulating, electronically commutating, braking, or otherwise controlling electric machines not otherwise provided for, e.g. machines using piezoelectric effects |
Attention is drawn to the following places, which may be of interest for search:
Curtain | |
Hand hammers, drills | |
Printers | |
Power steering | |
Heating cooling ventilating | |
Hybrid vehicle, conjoint control, arrangements for mounting | |
Electrically propelled vehicles, current collector, maglev | |
Lighting | |
Electric circuits for vehicle | |
Wiper control | |
Marine | |
Elevator | |
Washing machines, household appliances | |
Sliding roof, power window | |
Gas turbine | |
Starting of engine with electric motor | |
Windmills | |
Pumps, compressors | |
Motor cooling | |
Structure of the mechanical brake | |
Air-conditioning | |
Refrigeration | |
Measuring arrangements | |
Electromagnetic actuators | |
Safety, control principles | |
Position control, servos | |
Structure of the mechanical speed regulator | |
Control of linear speed, control of angular speed; control of acceleration or deceleration | |
Systems for regulating electric or magnetic variables using transformers, reactors or choke coils | |
Cooling fans for computers | |
Data storage device (hard disk CD, DVD BlueRay...) | |
Structure of the variable resistor | |
Magnets, inductances or transformers structurally associated with motors, generators, dynamo-electric converters, transformers, reactors or choke coils | |
Structure of the starter switch | |
Emergency protective arrangements with automatic interruption of supply | |
Circuit arrangement or systems for supplying or distributing electric power; Systems for storing electric energy, connection or control of one generator, transformer, reactor, choke coil or dynamo-electric converter with regard to conjoint operation with similar or other source of supply | |
Dynamo-electric machines structurally associated with motors, generators, dynamo-electric converters, transformers, reactors or choke coils | |
Apparatus for conversion between AC and AC, AC and DC or DC and DC and for use with mains or similar power supply systems; conversion of DC or AC input power into surge output power; control or regulation thereof | |
Automatic control, starting, synchronisation, or stabilisation of generators of electronic oscillations or pulses | |
Housing, cooling of housing |
In this place, the following terms or expressions are used with the meaning indicated:
control | means influencing a variable in any way, e.g. changing its direction or its value (including changing it to or from zero), maintaining it constant, limiting its range of variation |
regulation | means maintaining a variable automatically at a desired value or within a desired range of values, in which the variable is detected in the system and fed back for determining its deviation from the desired value. The determined deviation is used by the means for maintaining the variable to its desired value or values. Regulation is a form of "control". |
This place does not cover:
Starting of synchronous motors with electronic commutators except reluctance motors | |
Starting dynamo-electric motors rotating step by step | |
Vector control |
This place covers:
Arrangements or measures for starting a motor when the power re-establishes after a power failure, e.g. when the motor does not automatically starts turning.
This place covers:
In particular restarting before the motor has stopped.
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Repulsion start induction motor (RS-IM):
An alternating-current motor that starts as a repulsion motor; at a predetermined speed the commutator bars are short-circuited to give the equivalent of a squirrel-cage winding for operation as an induction motor with constant-speed characteristics.
Attention is drawn to the following places, which may be of interest for search:
Starting an individual polyphase induction motor |
This place covers:
- Starting of DC motors supplied with a DC voltage, whereby the motor is seen as an independent block not being further elaborated.
- Starting of commutated motors
- Starting of fan motors for a PC, also being supplied with DC
This place covers:
The resistance may be an actual resistor or it could also be a semiconductor operating in its linear region.
Attention is drawn to the following places, which may be of interest for search:
PWM controlled semiconductors |
This place covers:
In this group is for starting a commutator motor supplied by AC.
This place does not cover:
Starting of AC/DC commutator motors |
This place covers:
Repulsion start induction motor (RS-IM):
An alternating-current motor that starts as a repulsion motor; at a predetermined speed the commutator bars are short-circuited to give the equivalent of a squirrel-cage winding for operation as an induction motor with constant-speed characteristics.
The polyphase refers to the supply. An induction motor having main and auxiliary windings could be considered as a polyphase motor, but not within the meaning of H02P 1/26. They are classified in H02P 1/42 because they are supplied by a single phase power supply which supplies the main and auxiliary windings.
Attention is drawn to the following places, which may be of interest for search:
Repulsion start induction motor (RS-IM) |
This place covers:
Other means than an inverter
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Other means than an inverter.
This place covers:
Other means than an inverter.
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The resistance may be an actual resistor or it could also be a semiconductor operating in its linear region.
Attention is drawn to the following places, which may be of interest for search:
PWM controlled semiconductors |
Attention is drawn to the following places, which may be of interest for search:
Pole changing for purposes other then starting |
This place does not cover:
Using variable-frequency supply voltage, e.g. inverter or converter supply voltage |
Attention is drawn to the following places, which may be of interest for search:
Running of a single phase induction motor |
This place covers:
Any typical frequency converter can be used to start from almost DC to nominal speed without modifications. These documents are not to be classified in this group except in the case where special measures are integrated with the sole purpose of starting.
This place does not cover:
Using variable-frequency supply voltage, e.g. inverter or converter supply voltage |
Attention is drawn to the following places, which may be of interest for search:
Pole changing for purposes other then starting |
This place does not cover:
Starting an individual synchronous motor by pole-changing |
Attention is drawn to the following places, which may be of interest for search:
Pole changing for purposes other than starting |
This place does not cover:
Stopping of synchronous motors with electronic commutators except reluctance motors, | |
Stopping dynamo-electric motors rotating step by step | |
Vector control |
Attention is drawn to the following places, which may be of interest for search:
Arrangements for controlling dynamo-electric brakes or clutches | |
Electrodynamic brake systems for vehicles in general | |
Dynamic electric resistor braking | |
Dynamic electric regenerative braking | |
Eddy-current braking |
Attention is drawn to the following places, which may be of interest for search:
Brakes |
This place covers:
DC motors, i.e. a motor supplied with a DC voltage, whereby the motor is seen as an independent block not further elaborated. Typically this is a commutated motor, however e.g. a fan motor for a PC is also supplied with DC and therefore the starting of a PC fan motor is also classified here.
Attention is drawn to the following places, which may be of interest for search:
Commutator motor supplied with AC |
This place covers:
Arrangements where energy is not regenerated but lost in resistors or in the impedances of the motor.
This place covers:
Arrangements or measures where the energy is regenerated, e.g. kinetic energy is reused by sending it back to the supply or stored in an energy buffer.
In this place, the following terms or expressions are used with the meaning indicated:
AC motor | a motor supplied with an AC voltage, whereby the motor is seen as an independent block not further elaborated |
This place covers:
Arrangements where energy is not regenerated but lost in resistors or in the impedances of the motor.
This place does not cover:
Vector control |
This place does not cover:
Attention is drawn to the following places, which may be of interest for search:
Starting | |
Stopping | |
Synchronous motors or other dynamo-electric motors with electronic commutators in dependence on the rotor position | |
Motors rotating step by step | |
Vector control |
This place covers:
Differential gearboxes, where the output speed or phase represents the difference in speeds or phase.
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Arrangements, wherein the rotor and stator lines of first motor are coupled in parallel with the rotor and stator lines of second motor.
This place covers:
Providing control for a first motor which switches a second motor on during a limited portion of one revolution, in a fixed or predetermined ratio of movement, e.g. 120 degrees of 360 degrees.
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Not only the speed is equalized but also the phase, e.g. newspaper printing presses where a phase difference results in paper jams.
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Arrangement for controlling both a DC motor supplied with a DC voltage and an AC motor supplied with an AC voltage, whereby the DC motor or AC motor is seen as an independent load.
This place does not cover:
Speed regulation of two or more dynamo-electric motors in relation to one another |
Attention is drawn to the following places, which may be of interest for search:
Commutator motors supplied with AC |
A fan motor for a PC supplied with DC is also classified here.
This place covers:
Arrangement for controlling two or more DC motors supplied with a DC voltage, whereby the motor is seen as an independent load.
This place does not cover:
Attention is drawn to the following places, which may be of interest for search:
Commutator motor supplied with AC |
A fan motor for a PC supplied with DC is also classified here.
This place covers:
Arrangement for controlling two or more AC motors supplied with an AC voltage, whereby the motor is seen as an independent load.
This place covers:
Arrangements for controlling synchronous motors with electronic commutators where commutation is done in dependence on the rotor position, or other dynamo-electric motors with electronic commutators where commutation is done in dependence on the rotor position; Electronic commutators therefore
Brushless DC motors, e.g. BLDC motors, BL motors, electronically commutated motors, ECMs.
This place does not cover:
Vector control |
Attention is drawn to the following places, which may be of interest for search:
Motors rotating step by step | |
Other aspects of synchronous motors | |
Control of linear AC synchronous motors | |
Reluctance motors |
This place covers:
Control of torque ripple by controlling current wave shape, e.g. by using trapezoidal current.
The source of the torque ripple is commutation in this group. Reducing is done e.g. by controlling with trapezoidal current or other waveforms.
Attention is drawn to the following places, which may be of interest for search:
Reduction by changing commutation time | |
Any other source for reduction in torque ripple |
This place covers:
Delaying or advancing the moment of commutation of the electronic commutators from the time at which the commutation would have occurred based solely on the position of the rotor.
Attention is drawn to the following places, which may be of interest for search:
Change in current for reducing torque ripple |
This place covers:
All circuits and methods which detect the rotor position inside the motor (or outside if the rotor is mounted on the outside and the stator on the inside).
Attention is drawn to the following places, which may be of interest for search:
Detecting rotor position in synchronous AC motors | |
Position control outside the motor e.g. position of elements which are externally connected to the motor | |
Structural arrangement of position sensors associated with brushless motors or generators |
Attention is drawn to the following places, which may be of interest for search:
Current being modulated, e.g. by a high frequency component |
This place does not cover:
Controlling speed or torque of a single motor |
Attention is drawn to the following places, which may be of interest for search:
Starting in a selected direction |
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Starting without feedback from the position detection, e.g. when back emf is too low.
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Starting without a movement in the wrong direction e.g. for hard disks spindle motor.
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A direct link between the Hall sensors and the switching transistors enables a brushless motor to turn only in one direction and an additional circuit for enabling the brushless motor to run in both directions of rotation.
This place does not cover:
Arrangements for starting in a selected direction of rotation |
This place covers:
Circuitry or apparatus for regulating or controlling the speed or torque of electrical DC motors, e.g. brushed commutator motors, homopolar motors or a ball bearing motors.
The DC motor can be supplied by an AC voltage or AC current.
There are three types of connections used for DC electric commutator motors: series, shunt and compound.
An armature generally refers to one of the two principal electrical components of an electromechanical machine–generally in a motor or generator, but it may also mean the pole piece of a permanent magnet or electromagnet, or the moving iron part of a solenoid or relay.
The other component is simply to create a magnetic field, or a magnetic flux, for the armature to interact with, so this component can comprise either permanent magnets, or electromagnets formed by a conducting coil.
The armature, in contrast, must carry current so it is always a conductor or a conductive coil, oriented normal to both the field and to the direction of motion, torque (rotating machine), or force (linear machine). The armature's role is twofold. The first is to carry current crossing the field, thus creating shaft torque in a rotating machine or force in a linear machine. The second role is to generate an electromotive force (EMF).
Other DC motors are:
- A homopolar motor, which is an electric motor that works without the need for a commutator, by rotating along a fixed axis that is parallel to the external magnetic field produced by a permanent magnet. The name homopolar indicates that the electrical polarity of the motor does not change, i.e. that it does not require commutation. Such motors necessarily have a single-turn coil, which restricts their practical applications, since they must be used with low voltages and produce relatively small torques.
- A ball bearing motor, which is an electric motor that consists of two ball-bearing-type bearings, with the inner races mounted on a common conductive shaft, and the outer races connected to a high current, low voltage power supply.
Attention is drawn to the following places, which may be of interest for search:
Starting | |
Stopping | |
Synchronous motors or other dynamo-electric motors with electronic commutators in dependence on the rotor position | |
Motors rotating step by step | |
Vector control |
This place covers:
Tirrill regulator: A device for regulating the voltage of a generator, in which the field resistance of the exciter is short-circuited temporarily when the voltage drops.
This place covers:
A Ward Leonard drive is a high-power amplifier in the multi-kilowatt range, built from rotating electrical machinery. A Ward Leonard drive unit consists of a motor and generator with shafts coupled together. The motor, which turns at a constant speed, may be AC or DC powered. The generator is a DC generator, with field windings and armature windings. The input to the amplifier is applied to the field windings, and the output comes from the armature windings. The amplifier output is usually connected to a second motor, which moves the load, such as an elevator. With this arrangement, small changes in current applied to the input, and thus the generator field, result in large changes in the output, allowing smooth speed control. Armature voltage control only controls the motor speed from zero to motor base speed. If higher motor speeds are needed the motor field current can be lowered, however by doing this the available torque at the motor armature will be reduced. Another advantage for this method is that the speed of the motor can be controlled in both directions of rotation.
Group H02P 7/281 takes precedence over groups H02P 7/282 - H02P 7/298.
This place covers:
The use of a transistor or FET in linear mode (non switching)
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Using a Schmitt trigger with two thresholds.
This place does not cover:
Of the kind having a thyristor or the like in series with the power supply and the motor |
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Electronic switches that do not extinguish automatically.
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Rotating amplifiers, e.g. metadyne, amplidyne, rototrol, magnicon and magnavolt.
In this place, the following terms or expressions are used with the meaning indicated:
metadyne, amplidyne | The Metadyne and Amplidyne are special-purpose DC generators historically used as high power electro-mechanical amplifiers in control systems. In use, such machines are driven at constant speed by a motor. The electrical output is varied by control of field excitation, as in a Ward-Leonard system. The Metadyne and the Amplidyne include an arrangement of cross-connected brushes on one axis and a further set of brushes on a perpendicular axis. This arrangement allows the machine to provide very high gain, that is, large changes of output may be controlled by small changes in the controlling field current. |
rototrol (American Westinghouse Co.) | The rototrol is a two-stage machine with static and dynamic characteristics similar to those of the Amplidyne. The Rototrol may also be operated as a three-stage machine (also known as a Magnicon) in which the output is further used to excite a pole winding. |
In this place, the following terms or expressions are used with the meaning indicated:
Ward-Leonard system | a method of controlling the speed and direction of rotation of a DC motor by varying and if necessary reversing its armature voltage. A DC generator provides the variable armature supply. The output of the generator is controlled by control of its field current. |
Ward-Leonard drive | a high-power amplifier in the multi-kilowatt range, built from rotating electrical machinery. A Ward-Leonard drive unit consists of a motor and generator with shafts coupled together. The motor, which turns at a constant speed, may be AC or DC powered. The generator is a DC generator, with field windings and armature windings. The input to the amplifier is applied to the field windings, and the output comes from the armature windings. The amplifier output is usually connected to a second motor, which moves the load, such as an elevator. With this arrangement, small changes in current applied to the input, and thus the generator field, result in large changes in the output, allowing smooth speed control. Armature voltage control only controls the motor speed from zero to motor base speed. If higher motor speeds are needed the motor field current can be lowered, however by doing this the available torque at the motor armature will be reduced. Another advantage for this method is that the speed of the motor can be controlled in both directions of rotation. |
Armature | a rotor which carries a winding connected to a commutator |
This place covers:
Stepper motors have typically a large number poles which results in a large number of steps, and use permanent magnets resulting in high cogging torque and therefore in a large holding torque, even when the motor is not energized. The motor's position can be controlled precisely without any feedback mechanism (Open-loop control).
Attention is drawn to the following places, which may be of interest for search:
Vector control |
This place covers:
Control of current to increase commutation speed through the inductive windings, e.g. by measuring the coil current and generating a PWM controlled current or e.g. by applying a first higher voltage and a thereafter a lower voltage.
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e.g. by lowering the current to the minimum required to hold the position or by increasing the current when a step is required in particular using feedback to determine the movement.
This place covers:
Control of step size, including half step.
Attention is drawn to the following places, which may be of interest for search:
Ward-Leonard arrangements | |
Vector control | |
Feeding a network by two or more generators | |
For charging batteries |
This place does not cover:
Control effected upon generator excitation circuit to reduce harmful effects of overloads or transients |
Attention is drawn to the following places, which may be of interest for search:
Emergency protective arrangements with automatic interruption of supply |
This place covers:
Typically the rotor is moved by an external force and the rotor current is controlled such that a desired output voltage is achieved without an additional converter at the power output stage. The generator has typically two electrical connections and one mechanical input.
This place does not cover:
In this place, the following terms or expressions are used with the meaning indicated:
Tirrill regulator | A device for regulating the voltage of a generator, in which the field resistance of the exciter is short-circuited temporarily when the voltage drops (source: McGraw-Hill Dictionary of Scientific & Technical Terms). |
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Brushless excitation |
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Using magnetic devices with controllable degree of saturation in combination with controlled discharge tube or controlled semiconductor device |
Attention is drawn to the following places, which may be of interest for search:
Control circuits for doubly fed generators |
This place does not cover:
Control effected upon non-electric prime mover and dependent upon electric output value of the generator (effecting control of the prime mover in general, see the relevant class for such prime mover) | |
Using magnetic devices with controllable degree of saturation in combination with controlled discharge tube or controlled semiconductor device |
Attention is drawn to the following places, which may be of interest for search:
For the electrical supply of for the functioning of the battery or the electrical generator | |
Starter - generator | |
Balancing the load in a network (e.g. switching in extra loads like the airconditioning pump) | |
For charging batteries from dynamo-electric generators driven at varying speed, e.g. on vehicle |
Attention is drawn to the following places, which may be of interest for search:
Dynamo-electric converters are rotating machines whose purpose is not to provide mechanical power to loads but to convert one type of electric current into another, for example DC into AC. They are multi-field single-rotor devices with two or more sets of rotating contacts (either commutators or slip rings, as required), one to provide power to one set of armature windings to turn the device, and one or more attached to other windings to produce the output current. The rotary converter can directly convert, internally, any type of electric power into any other. This includes converting between direct current (DC) and alternating current (AC), three phase and single phase power, 25 Hz AC and 60 Hz AC, or many different output voltages at the same time. The size and mass of the rotor was made large so that the rotor would act as a flywheel to help smooth out any sudden surges or dropouts in the applied power. (source Wikipedia) Dynamo-electric converters are now obsolete technology. Modern electronic devices for controlling power in the kilowatt range include MOSFET and IGBT devices.
Attention is drawn to the following places, which may be of interest for search:
This place does not cover:
Vector control |
Attention is drawn to the following places, which may be of interest for search:
Controlling speed of dynamo-electric motors by means of a separate brake |
This place does not cover:
Vector control |
When classifying in this group, classification should also be made under H02P 25/00 when the method of control is characterised by the kind of motor being controlled. Classification should also be made under H02P 27/00 when the method of control is characterised by the kind of supply voltage of the motor being controlled.
In this place, the following terms or expressions are used with the meaning indicated:
Vector control | a method of controlling the speed of a three-phase AC motor by varying its power supply in accordance with a mathematical model of the machine flux. Stator currents are measured and transformed into a complex current space vector, allowing control of flux and torque. The vector components are then transformed to a rotating coordinate system and voltages calculated in this system are generated by an inverter and applied to the motor. |
Attention is drawn to the following places, which may be of interest for search:
Control strategies in general |
Attention is drawn to the following places, which may be of interest for search:
Arrangements for starting | |
Determining the initial rotor position | |
Arrangements for starting by vector control | |
Arrangements or methods for the control of AC motors specially adapted for very low speeds |
This place covers:
Synchronous Motor having an inherent instability, e.g. when it is used to drive a high inertia load. The motor ideally should spin at a constant angular velocity, but it instead sporadically oscillates about synchronous speed. This phenomenon is known as 'hunting'. This problem produces current ripples at the motor's electrical terminals and induces noise.
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- Reference frame conversion being based in the rotor
- Control is based on the rotor flux.
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- Reference frame conversion being based in the rotor
- Control is based on the stator flux.
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Estimation of changes in constants, e.g. temperature related changes in winding resistance.
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Arrangements for starting |
Attention is drawn to the following places, which may be of interest for search:
Position detection in general |
Attention is drawn to the following places, which may be of interest for search:
When classifying in this group, subject matter relating to vector control should also be made under H02P 21/00. Classification should also be made under H02P 25/00 when the method of control is characterised by the kind of motor being controlled. Classification should also be made under H02P 27/00 when the method of control is characterised by the kind of supply voltage of the motor being controlled.
Attention is drawn to the following places, which may be of interest for search:
Estimation or adaptation of motor parameters, e.g. rotor time constant, flux, speed, current or voltage | |
Control of angular speed of one shaft by controlling the prime mover |
This place covers:
A software algorithm that is only suitable in motor control which enables the implementation of a strategy in a processor (minimalising computing steps).
The motor parameters are stored in the in memory chip located in (or in the proximity of e.g. installed coder) the motor identifying the motor.
This place covers:
For attenuating the rotational velocity fluctuations of AC motors which spin at non-constant angular velocity.
Attention is drawn to the following places, which may be of interest for search:
Arrangements for controlling or reducing torque ripple in synchronous motors or electronically commutated motors | |
Control of reluctance motors | |
Motor oscillations that are synchronous to the motor position |
In this place, the following terms or expressions are used with the meaning indicated:
hunting | Hunting occurs when a synchronous motor is used to drive a high inertia load and sporadically oscillates about synchronous speed which induces noise. |
Attention is drawn to the following places, which may be of interest for search:
DC current braking |
Attention is drawn to the following places, which may be of interest for search:
Control of angular speed together with angular position or phase |
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The speed and the phase (or position) of a rotating shaft are both controlled to reach both a predetermined reference signal
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By acting on a device that is not the driving motor; for example, by acting on a brake.
Attention is drawn to the following places, which may be of interest for search:
Suitable for AC and DC motors |
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By acting on the supply of the motor that drives the shaft.
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Special control of the motor, e.g. by adapting the voltage and the phase/frequency fed to the motor.
In this place, the following terms or expressions are used with the meaning indicated:
DTC | Direct torque control is one method used in variable frequency drives to control the torque (and thus finally the speed) of three-phase AC electric motors. This involves calculating an estimate of the motor's magnetic flux and torque based on the measured voltage and current of the motor. |
Attention is drawn to the following places, which may be of interest for search:
When classifying in this group, subject matter relating to vector control should also be classified under H02P 21/00. Classification should also be made under H02P 27/00 when the method of control is characterised by the kind of supply voltage of the motor being controlled.
This place covers:
Circuit or methods which controls and detects the rotor position of the AC motor.
Attention is drawn to the following places, which may be of interest for search:
The motor being controlled based on the determined position |
Attention is drawn to the following places, which may be of interest for search:
Head positioning in hard disks |
This place does not cover:
Voice coil motors driven by DC |
Attention is drawn to the following places, which may be of interest for search:
Driving or moving heads in hard disks |
Attention is drawn to the following places, which may be of interest for search:
Direct torque control | |
Arrangements for reducing torque ripple |
This place does not cover:
Direct torque control |
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Reduction of torque ripple or 'cogging' torque arising from the construction of the motor, wherein the reluctance of the magnetic circuit changes as the motor revolves, for example due to differing rotor and stator saliencies.
Attention is drawn to the following places, which may be of interest for search:
AC motor control arrangements, other than vector control, specially adapted for damping motor oscillations or reducing hunting | |
Reduction of harmonics |
Attention is drawn to the following places, which may be of interest for search:
DC motors |
In this place, the following terms or expressions are used with the meaning indicated:
Repulsion motor | a type of electric motor for use on alternating current. It was formerly used as a traction motor for electric trains but has been superseded by other types of motors and is now only of historical interest. Repulsion motors are classified under Single Phase motors. In magnetic repulsion motors the stator windings are connected directly to the AC power supply and the rotor is connected to commutator and brush assembly, similar to that of a DC armature. |
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Shiftable brushes allow control of speed and/or torque
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Motors with shiftable brushes |
In this place, the following terms or expressions are used with the meaning indicated:
Series-wound motor | a universal motor when it has been designed to operate on either AC or DC power. It can operate well on AC because the current in both the field and the armature (and hence the resultant magnetic fields) will alternate (reverse polarity) in synchronism, and hence the resulting mechanical force will occur in a constant direction of rotation. |
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Motor being controlled by a control effected upon an AC generator supplying it |
This place does not cover:
Attention is drawn to the following places, which may be of interest for search:
When classifying in this group, subject matter relating to vector control should also be classified under H02P 21/00. Classification should also be made under H02P 25/00 when the method of control is characterised by the kind of motor being controlled.
If the supply is not particularly adapted for the control of a motor than it should not be classified here e.g. a variable voltage supply is suitable for a DC motor however it is suitable for various loads and therefore should be classified in a general voltage supply group e.g. H02M or G05B Only when the supply is exclusively for the control of AC motors these groups are used e.g. because control is influenced in function of a motor parameter (e.g. speed, torque, position, motor parameters etc)
Attention is drawn to the following places, which may be of interest for search:
Doubly fed motors | |
Doubly fed generators |
This place does not cover:
AC supply for both rotor and stator circuits, the frequency of supply to at least one circuit being variable |
In this place, the following terms or expressions are used with the meaning indicated:
Bang–bang controller (on–off controller) | is also known as a hysteresis controller, is a feedback controller that switches abruptly between two states |
Attention is drawn to the following places, which may be of interest for search:
Direct torque control per se |
In this place, the following terms or expressions are used with the meaning indicated:
DTC | Direct torque control is one method used in variable frequency drives to control the torque (and thus finally the speed) of three-phase AC electric motors. This involves calculating an estimate of the motor's magnetic flux and torque based on the measured voltage and current of the motor. |
This place does not cover:
Using AC supply for both rotor and stator circuits, the frequency of supply to at least one circuit being variable |
This place does not cover:
Starting | |
Stopping | |
Control of motors that can be connected to two or more different voltage or current supplies | |
Arrangements specially adapted for regulating or controlling the speed or torque of two or more electric motors | |
Vector control |
Attention is drawn to the following places, which may be of interest for search:
This place covers:
The (prime mover) motor is supplied with a constant power supply. Some means connected (mechanically) with the motor and the load influences the speed.
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Motor regulation or control guarding against excessive voltage or amperage while power is maintained, e.g. protection against broken phase or power surge/failure
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Protection for stepper motors |
Attention is drawn to the following places, which may be of interest for search:
Protection during start | |
Generator overload and transient protection | |
Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for dynamo-electric motors | |
Emergency protective arrangements with automatic interruption of supply | |
Emergency protective circuit arrangements for limiting excess current or voltage without disconnection, in general | |
Protection of inverter circuit |
Attention is drawn to the following places, which may be of interest for search:
From commutation | |
Motor oscillation | |
In Reluctance motors | |
EMI interference reduction on the converter side |
This place does not cover:
Protection against overload |
Attention is drawn to the following places, which may be of interest for search:
Protection against faults of stepper motors | |
Motor parameter estimation for vector control | |
AC motor parameter estimation | |
Measuring temperature |
This place does not cover:
By back-EMF evaluation to obtain the motor temperature |
Attention is drawn to the following places, which may be of interest for search:
Back-EMF based rotor position determination |
Attention is drawn to the following places, which may be of interest for search:
Conversion of DC or AC input power into surge output power |
Attention is drawn to the following places, which may be of interest for search:
Conversion of DC or AC input power into surge output power |
Attention is drawn to the following places, which may be of interest for search:
Conversion of DC or AC input power into surge output power |
Attention is drawn to the following places, which may be of interest for search:
Conversion of DC or AC input power into surge output power |
Attention is drawn to the following places, which may be of interest for search:
Power factor control [PFC] of AC motors |
Attention is drawn to the following places, which may be of interest for search:
Circuit arrangements for detecting rotor position using inductance sensing, e.g. pulse excitation, to control synchronous motors or other dynamo-electric motors |