SU649971A1 - Synchronous electric motor electromagnetic torque measuring device - Google Patents

Description

ku; in fig. 2 is a block diagram of a device for an electric motor with more than one stator windings. The device contains resistors 1 and 2, connected in series with the stator winding 3, voltmeter 4, measuring winding 5, differentiating unit 6, scaling amplifier 7, integrating unit 8, identical 3 input computing units 9 and 10, angular velocity sensor 11, unit 12 subtracting, recording devices 13, 14, 15. For electric motors containing more than one stator winding 3, the device includes two adders 16 and 17 corresponding to inputs “a,” b, “c, etc.” to, "l," L1, and so on, but the number of stator windings is 3. With the help of The structure of the reactive moment is determined by its expression with an unsaturated magnetic core (p, const) tm tt f (0) y; -1 /, - Y-1f, 2 X9 2 X0 ft ift-i g, (c) -jal) where M is a {9) -reactive moment; M (9), M2 (0) - components of the reactive moment; p, is the magnetic permeability of the material of the magnetic circuit; 9 is the angle of rotation of the rotor, t is the number of stator windings 3; k is the number of the stator winding 3; tfe - current of the st stator winding 3; - flux linkage of the 4th stator winding 3. Applying signals from the adder of subtractor 12 from adders 16 and 17 proportional to the components of the reactive moment, the output of block 12 of subtraction receives a signal proportional to the reactive moment. The component of the reactive moment MI (9) is equal to: ЖЛв): У-1гй 2 ЙЭ -0.5; S ik Ik -Г7-Т7 where the angular velocity of the rotor, rad / s; Wik is the number of turns / rth stator winding 3; zk is the number of turns of the th measuring winding 5; Ik - k-vi EMF of measuring winding 5. Attaching to the inputs of computing units 9, etc., the outputs of which are denoted by the positions "a," b, "e, etc., EMF of measuring windings, EMF of the angular velocity sensor and the voltage of the resistors, proportional to the currents of the stator windings, at the output of the adder 16, we obtain a signal proportional to the component Mi (9). The component of the reactive moment M2 (9) is equal to)., Dt. (3) -0.5 2 W211 dejdt dt. Signals proportional to dik and lkd (, о are taken from differentiating and integrating blocks 6 and 8, respectively. Attaching to the inputs of computing blocks 10, etc., the outputs of which are the positions "k," l, "m, etc. and, proportional to the integrals of the EMF of the measuring windings 5, derived from the currents of the stator windings 3 and the EMF of the sensor AND the angular velocity, at the output of the adder 17, we receive a signal equal to the normal component of the reactive torque 2 (9). stator winding 3 (Fig. 1), pa It works as follows. From the terminals of resistors 1 and 2, the signals pronounced current to the stator winding 3 are fed to the inputs of the differentiating unit 6 and the mass-stabilizing amplifier 7, respectively, and the EMF of the measuring winding 5 is applied to the input of the integrating unit 8. The computing unit 9 calculates the component of the reactive moment, equal to the product of the current of the stator winding 3 and the EMF of the measuring winding 5, divided by the angular velocity of the rotor - the sensor's EMF I. The computational unit 10 calculates the second component of the reactor actual time, equal to the product of the derivative of the current of the stator winding 3 and the integral of the EMF of the measuring winding 5, divided by the EMF of the sensor I. The reactive moment equal to the difference of the two components is calculated in subtraction unit 12, to the input of which the output signals are fed directly from the computing units 9 and 10. Reactive moment M (Q) and its components MI (9) and MS (9) are recorded respectively by elements 14, 15 and 13.

The voltage across the stator winding 3 is monitored with a voltmeter 4.

A device for measuring the torque of an engine containing several stator windings 3 (FIG. 2) operates similarly to the device described above. The signal proportional to the first component of the moment is removed from the adder 16, the inputs of which are a, b, 8, etc., receive signals from the computing blocks in functions similar to the computing block 9. The signal proportional to the second the moment is removed from the adder 17, the inputs of which “k,” l, “lg, etc., receive signals from the computational units by functions, anaLogical computational unit 10.

The reactive moment is calculated in block 12, to the INPUTS of which signals are supplied from adders 16 and 17.

The scaling of the output signals of the computing blocks 9 and 10 is carried out using predetermined constant voltages applied to the input of these blocks.

The tuning of the differentiating and integrating blocks 6. And 8 is made by the reference sinusoidal signals. When tuning with the help of scaling amplifiers included in these blocks, the values of the input and output voltages of the integrating unit 8 are the same, and the input voltage of the differentiating unit 6 r times its output voltage (g - resistance of the resistor 1, the voltage of which is applied to the input of the differentiating unit 6).

The adjustment of the scaling amplifier 7 is made using a constant or sinusoidal reference voltage. The input voltage of the scaling amplifier 7B TI times must exceed its output voltage (ri - the resistance of the resistor 2, the voltage of which is applied to the input of the scaling amplifier 7). The invention eliminates the component of measurement error.

due to the uneven rotation of the rotor of the engine within a revolution, and the technical capabilities of the device are expanded, since the output signals can be either registered by the recording elements or entered into other computing devices to automate the measurement.

FORUMUA AND 3 ABOUT AND

Claims (2)

1. A device for measuring the electromagnetic moment of a synchronous motor, containing an EMF sensor in the form of a measuring winding, located in a stator winding zone, a differentiating and integrating unit, a mass-stabilizing amplifier, two computational units with three inputs and recording elements, two inputs of one computational unit are connected to the output of the main amplifying amplifier and measuring winding, and two inputs of another computational unit - to the outputs of the differentiating and integrating units, characterized in that, in order to increase accuracy, the device is equipped with a subtraction unit with a recording element and an angular velocity sensor containing the shaft, assigned to a rigid connection to the motor shaft, and a winding connected to the third input of one and the other computational units, the outputs of which are connected to the subtraction unit. 2. The device according to claim 1, that is, so that, in order to expand the field of application to the t-phase synchronous motors, an additional 2 (t-1) computing blocks are introduced, and between the computing blocks and the subtraction block included two adders. Sources of information taken into account during the examination 1. USSR Author's Certificate No. 342093, cl. G OIL 3/00, 1970. 2. USSR Copyright Certificate No. 334495, cl. G OIL 3/00, H 02K P / OO, 1970. // T 15 9 R  G 15 -T g K