121 results about "Motor constants" patented technology

It is attained by being provided with a motor constant calculation unit for calculating electric constants of a motor, and by correcting setting values of electric constants defined on one of the axes of two orthogonal axes, by a functional expression using a state variable defined on the same axis, and by correcting them by a functional expression using a state variable defined on the other axis.

A method of measuring a motor constant is provided in a vector control apparatus for an induction motor. A voltage output phase [theta]v is set at an previously set arbitrary phase. Prior to applying a current, a current command is fed to operate the vector control apparatus with a proportional-plus-integral controller being set operative. After conduction for a predetermined time, the gain of the proportional-plus-integral controller is set to zero to maintain an integrated value constant and accordingly fix a voltage command value. In this state, a current command value and a detected current value are measured. k is measured at two levels of current, and a primary resistance value (or a line-to-line resistance value) is derived from the slope.

A method and apparatus are provided for detecting a rotor lock condition in a sensorless permanent magnet synchronous motor. A BEMF observer determines an estimated rotor speed {circumflex over (ω)} and a first BEMF voltage value in an estimated rotor-related γ,δ reference frame. In addition, a second estimated BEMF voltage value is calculated in a rotor-related d,q reference frame based on at least a first motor constant and an estimated rotor speed {circumflex over (ω)}. After generating a BEMF error filter value from the first and second estimated BEMF voltage values and calculating a BEMF error threshold value as a function of the estimated rotor speed {circumflex over (ω)} that is subject to a minimum threshold BEMF value, a rotor lock condition is detected based on at least the BEMF error filter value and the BEMF error threshold value.

A motor control device includes a magnetization control unit energizing a motor winding to change magnetic flux content of permanent magnet motor, a current detector detecting current supplied to the motor, a vector control unit including a speed / position estimation unit carrying out an operation to estimate a motor rotational speed and rotational position, the vector control unit carrying out a vector control of the motor, an induced voltage detector detecting an induced voltage of the motor based on the rotational speed, motor currents obtained by the vector control unit, output voltages of the drive unit, a winding inductance or the motor constant and a winding resistance, an induced voltage command determining unit determining an induced voltage command based on the motor rotational speed and output torque, and a magnetization current determining unit determining an amount of energization based on the induced voltage of the motor and the induced voltage command.

A vector controller for a permanent magnet synchronous motor uses current command values and detected currents of the d-axis and q-axis, a calculated frequency, and motor constant settings to control the output voltage of a power converter; the motor constants are identified by use of active or reactive power obtained from the output voltage and detected current of the power converter, the calculated frequency, and the detected current immediately before or during an actual operation.

A vector control system for a permanent magnet synchronous motor, using a current control equivalent output value, a frequency instruction value, a current detection value, an inference phase error value, and a motor constant, identifies a motor resistance equivalent or a resistance setting error equivalent. Next, the vector control unit, using the identified value, corrects a set value R* equivalent of a voltage instruction calculation unit and a n inference phase error calculation unit.Thereby, a vector control system for a permanent magnet synchronous motor can realize a robust control characteristic for changing of a resistance constant of a motor in a low rotation speed area under position sensor-less control. Further, a vector control system for a permanent magnet synchronous motor can be applied in common in a system performing inexpensive current detection.

A motor control device is disclosed which is arranged so as to perform a PWM control for a permanent magnet motor including a rotor having a permanent magnet and a stator with a multiphase winding. The motor control device includes a position detection unit which executes an analog computation process for induced voltages of respective phases of the motor based on a phase voltage equation having, as operation terms, respective phase voltages, respective phase currents, winding inductance, winding resistance and a neutral point voltage, the winding inductance and the winding resistance being motor constants of the motor, thereby generating and delivering a rotational position signal of the rotor based on a phase relation of the induced voltages, and a digital processing unit which has a function of generating and delivering a sinusoidal PWM signal based on the rotational position signal, thereby controlling the motor.

An electric motor control device includes: a motor constant generator configured to generate a motor constant by using a temperature as a parameter; a current control unit configured to generate a current command value to an electric motor based on the motor constant and a torque command value and execute a current control mode in which a voltage applied to the electric motor is controlled to match the current command value; a voltage phase control unit configured to calculate a torque estimation value of the electric motor and execute a voltage phase control mode in which a feedback operation is performed for a voltage phase based on the difference between the torque estimation value and the torque command value; and a control mode switching unit configured to switch to the voltage phase control mode in a high rotation area where a flux weakening control is performed. The torque estimation value is calculated using the motor constant common to generation of the current command value in the current control mode.

A motor control device includes a current detecting unit detecting current flowing into a motor winding, a speed / electrical angle estimating unit estimating a rotational speed and an electrical angle of the motor, based on the current, a load torque estimating unit estimating load torque to be developed by a load, from a torque current obtained based on the current and the electrical angle, a motor constant and inertia moment of the motor inclusive of the load, a load torque phase calculating unit calculating a phase of periodic fluctuation indicated by the load torque, a torque-compensating current determining unit determining a sinusoidal torque-compensating current, based on the load torque phase, and an amplitude / phase adjusting unit detecting speed fluctuation of the motor to adjust amplitude and phase of the torque compensating current by increasing or decreasing the amplitude and the phase so that the speed fluctuation is reduced.

The invention discloses a motor constant-speed forward / reverse rotation control circuit. A control signal output pin of a master chip outputs motor forward / reverse rotation control signals to the base electrode of a third crystal triode, the collector electrode of the third crystal triode is connected with a power source by an electromagnetic relay, and the electromagnetic relay is provided with at least a first moving contact and a second moving contact which are correspondingly communicated with the positive pole and the negative pole of the motor; the normally closed contact of the electromagnetic relay corresponding to the first moving contact is connected with the collector electrode of a first crystal triode, and the corresponding normally open contact is earthed; the normally closed contact of the electromagnetic relay corresponding to the second moving contact is earthed, and the corresponding normally open contact is connected with the collector electrode of the first crystal triode; and the base electrode of the first crystal triode is connected with the collector electrode of a second crystal triode, and a modulation signal output pin of the master chip outputs PWM signals to the base electrode of the second crystal triode. By controlling the electromagnetic relay based on the motor forward / reverse rotation control signals to realize the forward / reverse rotation of the motor and determining the rotation speed of the motor based on PWM signals, the invention has the advantages of high stability and low failure rate.

Size and weight reduction of a motor-driven vehicle, robot or the like is achieved. A current command Iref from a speed feedback gain is supplied to each of circuits with coefficients of sin(θm), sin(θm+2π / 3) and sin(θm−2π / 3) to generate three-phase signals. The three-phase signals are respectively supplied to current control gains through adder-subtracters. Further, signals from motor constants are added together by an adder to produce motor torque. Furthermore, coil voltages output from adders pass through diodes and are then added together by an adder, and the signal is supplied to a regenerative voltage determiner. When a regenerative voltage becomes excessive, in-phase current Idc is supplied through a regeneration control gain to adder-subtracters.