SU781179A1 - Device for measuring momentum and shaft power of direct current electrical machine with additional pole coiling - Google Patents

Description

(54) DEVICE FOR MEASURING THE MOMENT AND POWER ON THE SHAFT OF THE ELECTRIC CURRENT OF THE DIRECT CURRENT WITH THE WELDING OF ADDITIONAL POLES modes. A device for measuring the static moment of load on a DC motor shaft is known, comprising a dynamic torque torque measurement unit in the form of a tachogenerator with a differentiating link, a total torque measurement unit made in the form of a tachometer bridge, the core windings and additional motor poles are included in the adjacent arms, and, accordingly, two resistances of the delta device, one input of which is connected to the diagonal of the bridge, the other to the main winding of the tachogenerator and the multiplying mouth The device, one input of which is connected to the winding with additional motor poles, the other with the output of a dividing device, and a summation unit connected by one input to a differential link, and the other to the output of a multiplying device}}. However, this device does not provide the required Measurement Accuracy and does not allow the measurement of torque when the engine is running in generator mode. The closest in technical essence and the achieved result to the proposed is a device for measuring the torque and power on the shaft of a DC electric machine with a winding of additional poles, containing a unit for determining the EMF of the rotor as a function of the current in the rotor circuit with a DC amplifier, the EMF multiplying unit the rotor on the current in the rotor circuit and the dividing unit connected to one input with the rotor speed sensor and the output to the torque meter 2. The disadvantage of such a device is also low measurement accuracy rhenium.

781179

The purpose of the invention is to increase the accuracy of imereons.

This goal is achieved by introducing into the device a unit for determining total losses in steel and mechanical losses of power in the car, connected with an input to a rotor frequency sensor, a summation unit, one input that is connected to the output of the block multiplied; the other to the output the total loss determination unit, and the output output of the target unit and the power meter associated with the output of the summation unit, and the unit for determining the EMF of the rotor is provided at the output with an algebraic summation node, one g: whose input is connected with the output force ate DC, and another - to the rotor circuit, wherein the gain is the ratio of the resistance values of the rotor circuit to the value of resistance of the winding of additional poles, which is connected to the input of amplifier.

The drawing shows a diagram of the proposed device.

The device contains a foiKi3 sensor 1 of the electric machine's 2-core circuit 2, a multiplication unit 3, one input of which is connected to the IP sensor 1 and another - with the rotor EMF determination unit 4 as a function of current in the rotor circuit. -. - -

Unit 4 consists of a node 5 of algebraic summation of voltages and a DC amplifier 6. One of the inputs of node 5 is connected to the root circuit of machine 2, and the other is connected to the output of amplifier 6, the input of which is connected to the winding of 7 additional poles of the machine I.

The output of multiplication unit 3 is connected to one input of summation unit 8, the other input of which is connected to the output of unit 9 for determining the total steel loss and mechanical power loss in machine 2 depending on the speed of rotation of its rotor controlled by a tachogenerator 10. The main circuit of the tachogenerator 10 is connected the input unit 9 and one input unit 11 division.

A power meter 12 and an OTHER input of a dividing unit 11 are connected to the output of the block 8 suK “mI rOwNy” and the OTHER input of the dividing unit 11, the output of which is connected to the torque meter 13.

The device works as follows. .. „, ..„ ..,. ..., .........;.,.,. .: ..... „.

When the electric machine 2 is in operation, a signal from the sensor (shunt) 1 of the current is transmitted to one input of the multiplier 3;

The current is a root crust, and to another input there is a signal, n {) is the reference EMF developed by an electrical machine. The value of this EMF is equal to

 ± li, v

where (J is the value of the voltage supplied to the machine's main circuit from the mains, or by developing a machine in a generator operating mode;

di voltage drop in the car's crown chain.

Thus, at the output of block 3, a voltage appears that is proportional to the power on the shaft of the electric machine without taking into account the total loss in steel and the mechanical power loss in the machine itself.

and, (and ±),

where K is the proportionality coefficient;

3 ok kornoy chain electric machine.

The EMF of the electric machine.2 is determined by block 4. To take into account the change in the resistance of the windings of the core circuit of the machine 2 when the temperature of the temperature changes, the input of the DC amplifier 6 is connected to the winding of 7 additional poles of the machine. The amplifier 6 increases the voltage taken from the winding 7 as many times as its resistance is less than the total resistance of the core circuit elements connected to the node 5 of the algebraic summation of voltages. Node 5 automatically removes voltages and UEs. In generating mode

machine operation 2 U and LU values are summed, and in the motor one, the voltage drop J is subtracted from the voltage U.

The voltage from the output of block 3 is multiplied to the input of block 8 summation, to another input of which voltage is supplied from the output of block 9, the proportion (the total total loss in steel and mechanical power loss in the machine 2 itself, depending on of the speed of its rotation. At the output of block 8, a voltage proportional to the power appears. In the generator mode, an electric

machine, and in the motor - on the shaft of the machine of direct current. This voltage is recorded by a power meter 12, and is also fed to one of the inputs of dividing unit 11, which is carried out

is the division of a voltage proportional to the power at the ball of the machine, which is proportional to the speed of rotation of its shaft.

Thus, the voltage at the output of the dividing unit 11 is propagating the torque to the shaft of the electric machine of direct current supplied to the machine in the generator mode of its operation and developed in the motor mode.

The use of the device makes it possible to increase the accuracy of measuring the moment and power on the shaft of the electric machine, direct current when it is operated in the engine mode and in the generator mode.

Claims (2)

1. Copyright certificate № 42O8931 Cl. Q 01 L 3/22, 23.05.1972 2. USSR author's certificate N 159482, 12.22.77 (prototype).