SU1272413A2 - Rectifier electric motor - Google Patents

Abstract

The invention relates to electrical engineering, namely to el. cars. The aim of the invention is to improve the reliability of a valve motor (HP). The VD contains a synchronous machine 1, the sections of which the core winding through an inverter 2 is connected to the source 3 of an adjustable voltage. There are a rotor position sensor 9, a rotational direction indicator 10, a sawtooth voltage generator I1, and null organs 12-14 with different levels (L with: tc 4 CO N

Description

there is a displacement of the operating point. Three logical elements (E) are entered into the channel of the channel. In the first channel, these are logical E 16-18. The first inputs of these E directly or through the keys 19 are connected to the outputs of the corresponding null organs. The second inputs are connected to the corresponding devices 20 for converting signals from the sensor 9 of the rotor position into pulses of 60 electr duration. hail. This channel also includes inverting logic E 22 and 58, logical E matching 23, 24, 29, 30, static trigger 38 and key 39. Additionally, an operation mode determination unit 54, a unit 55 comparing the actual speed level with a preset and a static trigger are entered 57. The first input of a static trigger through E coincide 56.c is connected with the outputs of block 54

determining the operation mode and the block 55, and the second input through the differentiation of the chain 21 is connected to the sensor 9 of the rotor position. The operation mode determination unit 54 contains logical EI-NE 59-62, and static trigger 57 logical E-NE 63 and 64. Thanks to the newly introduced E, the switching process of the control zones of the inverter of the motor inverter thyristor occurs after changing the direction of rotation and coincides with the moment of input the next control pulse to the thyristors of the inverter, which excludes the possibility of connecting at the moment of transition of the motor speed through zero winding sections that do not correspond to the specified direction of rotation. This reduces additional fluctuations.

speed and reliability

bot bot 2 Il. .

The invention relates to the field of electrical engineering, in particular to valve electric motors (BD) of an adjustable AC electric drive, can be used in electric drives of machine tools and other mechanisms and is an improvement of the device according to the author. St. B 970578.

The purpose of the invention is to increase the reliability of a valve motor.

FIG. 1 is a schematic diagram of the proposed valve; Go electric motor; in fig. 2 detailed diagrams for the device operation.

FIG. Figure 2 shows the graphs of the component parts of the motor torque versus the angle of rotation of the rotor developed by separate phases of the core winding when the current is flowing around j-ix 1, the moment is calculated by the formula

m P s, U

 .five

where P is the power phase of the engine; rotor speed

engine;

 - instantaneous value of the EMF of rotation.

U-, o, .Uii and „, Uj ,, ,,, Ugj and Ug are the logic signals at the outputs of the corresponding circuit elements of FIG. one.

The DB contains synchronous maschina 1, the core winding sections through the inverter 2 are connected to an adjustable voltage source 3, for example, adjustable rectifier 4 with a system 5 of pulsed-phase control, a current and speed control system 6, a zero current sensor 7, a setting device 8 speeds and directions of rotation. There is a rotor position sensor 9.

The outputs of the path sensor channels are connected to the inputs of the rotational direction indicator 10 and the 11 5 sawtooth voltage generator, containing, for example, a counting device and a code-analog converter. The output of the sawtooth generator is connected to the inputs of the null organs 1214, which have a different level of displacement of the operating point. The second inputs of the zero-organs are combined and connected to the output of the setting device 15 of the inverter control angle. There are three for each channel logic element matches with the combined outputs (the first channel logic elements 16-J8), the first inputs of which directly or through the keys I9 (for reversing VD) are connected to the outputs of the corresponding zero-organs. The second inputs of the logic elements 16-18 are connected to the corresponding outputs of the device 20 for converting signals from the rotor-position sensor, pulses of duration 60 e. hail. devices. 20 through differential circuits 2I are also connected to the input of the generator 1 1 of the cross-sectional stresses. The combined outputs of the logic elements 16-18 coincidence are connected via inversions of the logic element 22 to the inputs of the logic elements 23 and 24 of the first group, the second inputs of which are connected respectively directly and through the inverting logic element 25 (for other control channels through the logic elements 26 and 27) and keys 28 (for reverse HP) to the input of the rotor position sensor. There are logic elements 29 and 30 of the second group coincidence, the first inputs of which are connected respectively directly and through the inverting logic element 31 (for other control channels through logic circuits 32 and 33) to the output of the sensor, the position of the DB rotor.

The second inputs of logic elements 29 and 30 of the second group coincidence are combined and connected via the logical element AND-NOT 34 to the TERMINALS of node 35 of differentiating the fronts of the signals from the indicator of rotational direction, fixing unit 36, the initial state of the circuit representing, for example, the relay element , included in the initial state of the circuit, and the logic device 37 of the non-current mode switching operation. The corresponding outputs of the additionally introduced logic elements of the coincidence of the first and second groups are combined and connected to the inputs of static triggers (for the first

control channel to the input of the static trigger 38), the outputs of which directly or through the keys 39 (for non-reversible VD with braking and reversing VD) are connected to the corresponding inputs of the decoder of signals from the triggers. Logic elements 16-18, 22-24, 29 and 30 with trigger 38 and keys 39 are designed to form control zones of the inverter thyrephors connected to phase A of a synchronous machine. To control the inverse phase, the thyristors of the inverter connected to the phases B and C of the synchronous machine are circuit groups 40 and 41.

The outputs of the decoder on the logic elements are connected to the inputs of the pulse devices 48-53 of the inverter thyristors.

The device also contains a mode determination mode 54, a unit 55 comparing the actual speed level with a given one, a matching element 56 and a static trigger 57, the first input of which is connected to the operating mode determining unit 54 and the actual speed level comparing unit 55 through the matching element 56 with the given one, and the second input through differential chains 21 - with the sensor 9 of the rotor position. The first output of the static trigger 57 is connected via inverting logic element 58 with the second inputs of logic elements 23 and 24 of the first group, and the second output through the element 34 of coincidence with the second inputs of logical elements 29 and 30 of the second group. The first input of the operation mode determination unit 54 is connected to the output of the rotation direction shaker 10, and the second to the output of the logic device 37 for currentless operation switching. The input of the unit 55, comparing the actual level of speed with the setpoint, is connected via differential chains 21 to the 9th rotor positions.

The operation mode determination unit 54 contains AND-NOT 5962 logic elements. Static trigger 57 contains logical elements AND-NOT 63 and 64.

All said connection of input elements at low speed in the braking mode blocks the operation of logic elements, matching the first group through which the phase-controlled pulses pass, and the operation of the second group of elements passing through the non-phase-controlled pulses from the position sensor the rotor, when using which the angles of control of the inverter keys when changing the direction of rotation change without additional switching from c1 O in braking mode to f) O in the motor mode (with respect to the intersection point of the phase EMF of the idle run of the synchronous machine), which eliminates the incorrect connection of the sections of the synchronous machine. Automatic change of the control angles from o (0 to 0 when changing the direction of rotation occurs because the forward direction of the rotor position sensor starts when the leverage of the sector of the disk coincides with the sensitive head, and when directed backward, it coincides with the rear part of the sector of the disk, which is equivalent to changing the phase of the control signal to 180 el. hail. The transition to the angle adjustment mode f occurs as a function of the signal from the differentiating chains, issuing it to 0, after switching the rotational direction indicator or simultaneously with it and the output of the sensor of the signal mode, indicating the motor mode, i.e. when the change of direction of rotation is complete. In the initial state of the circuit, at the output of the speed setting knob 8, the zero signal, the rectifier thyristor control angles are close to 160 el. hail. and the voltage at the output of source 3 of controlled voltage is zero. The output of node 36 of fixing the initial state of the circuit is a logical zero which brings the counting device of the sawtooth generator to the initial state when there is also a zero signal at its output. At the same time, depending on the signal level from the device 15, a logical zero can be at the output of all zero organs or only two. In the first case, at the output of logic elements 16-18, the first control channel coincides, as well as at the output of similar elements of other channels, a logical unit is output, the output of the inverting logic element 22 is a logical zero, and at the outputs of elements 23 and 24, a logical unit which does not affect the state of the flip-flop 38. At the same time, at the output of the NAND 34 logic element, under the action of a signal from the node 36, a logical unit appears that removes the blocking from the input of the logic elements. 29 and 30 match. The signal at the output of the elements 29 and 30, and hence the state of the trigger 38, is determined by the signal at their first inputs from the rotor position sensor. In the second case, when the logical unit at the output of one of the null organs, the signals at the outputs of the logic elements 23 and 29, 24 and 30 coincide and are determined by signals from the rotor position sensor. Signals from static outputs. . the triggers through the keys 39 (for the first control channel) are fed to the inputs of matching elements 42-47, the third inputs of which receive the assembly of control pulses of the controlled rectifier and the control pulses of the inverter, formed, for example, on the switching fronts of the trigger 38 and the other control channel triggers. If there are logical units on all the third inputs of the corresponding two of the six logic elements 4247, a logical zero appears on their codes, and two of the six pulse devices 48-53 appear at the output of the two; A control signal appears that opens the corresponding two inverter thyristors. But since there is no voltage at the output of the rectifier, the current in the sections of the synchronous machine does not leak and the rotor of the engine is stationary. At the output of block 55 of the severity of the actual level of speed with a given c. the stationary state of the rotor signal corresponds to the blade unit, and the signals at the outputs of the rotational direction indicator 10 and the device 37 for current-free switching of operation modes are not defined, not defined, and the signals at the output of the unit 54 are determined. Neither the mode of operation and, therefore, the outputs of the static trigger 57. However, its signals either do not affect the static trigger 38 (in one position of the trigger 57) or confirm its status (in a different position of the trigger 57), determined by signals from 9 position of the rotor in accordance with the signal from the node 36 fixation of the initial, state. scheme. When a voltage appears at the output of the speed limiter of a given field, corresponding, for example, to the Forward direction, the angles of control of the thyristor rectifier 4 become less than 90 e. hail, and the output of the rectifier 4. voltage appears. At the same time, the logic device 37 switches to the state corresponding to the Forward direction, while switching the keys 39 to the position where the inputs from the logic elements 42-47 come from the outputs triggers 38 (for the first control channel, also corresponding to the Forward direction. At the outputs of two pulse devices, control pulses appear, two thyristors of inverter 2 open and along sections of the synchronous machine in accordance with the state of the rotor position sensor The rotor of the engine turns to a certain angle. The indicator 1 of the direction of rotation turns on in the state corresponding to the Forward direction, including the keys 19 in the same direction. When the rotor turns at the output of the 11 sawtooth voltage generator, the signal decreases according to a linear law ( a DB scheme can be built up, which also works to increase the signal at the output of the sawtooth generator.) When the zero-body 12 decreases at the output of the sum of signals from the generator I 1 and the source of displacement below the signal from the rear tchika 15 at its output is at logic one, which is supplied to a first input of NAND gate 6 of the first control channel and first inputs of similar elements of the second and third channels are grappling. At the same time, in accordance with the 60-degree resolution zone (presence of a logical unit at the second input, for example, logic element 16 from device 20), the signal from the zero-body passes through logic element 22 to the input of logic elements 23 and 24, one of the first the inputs of which receive the resolution signal (logical unit) with a duration of 180 e. hail, through the keys 28 from the rotor position sensor 9. If there are two logical units at the input of the logic element 23, a logical zero appears at its output, which switches the static trigger 38. The signal at the inputs of the AND-NE logic elements 42, 43, .46 and 47 changes, which leads to the inclusion of other impulse devices and the opening of another pair of keys of the inverter 2. At the same time, the load current flows through other sections of the synchronous machine and the rotor of the motor begins to turn for the next 60 degrees. At the moments of changing signals from the rotor position sensor channels (over 60 electr.), The differentiating chains 21 pass the apertures on the front of the signal to the input of the sawtooth generator, which returns the generator to its original state. Upon further rotation of the rotor, the signal at its output again decreases according to a linear law and after it decreases below the driver from the setting unit 15, the zero-body is turned on again and the signal from it passes in accordance with the resolution zones from the device 20 and from the rotor position sensor to the static trigger input , but already another dripping control. The switching of the keys of the inverter 2 again occurs and the rotor turns by another 60 el. hail. Synchronous MaimiHa works in motor mode. At the same time, logical units are located at the output of nodes 35 and 36, and at the gate of AND-NE 34 there is a logical zero, which prevents the signal from the rotor position sensor from passing to the logic elements 29 and 30. The static trigger is controlled by signals from the null body in accordance with the eon resolution signals from sensors 9, coming through the keys 28 and logic elements 25-27 to the inputs of logic elements 23 and 24. When the database is in motor mode, the signal at the output of the operation mode determination unit 54 corresponds to logic-o. zero, and the output of the coincidence element 56 coincides with a logical one that does not affect the state of the static trigger 57, switched sigiampamp from the block of differential chains 21 to the state when its first output is (output of the logical element AND IS NOT 64 ) is a logical zero, and at its second output (output of the NAND gate 63) is a logical one. The signal for switching the DB to the braking mode or to the reverse comes from the current and speed control system 6. In this case, the rectifier thyristors 4 are switched to the inverter mode, the current of the synchronous machine section drops to yule, the logic device 37 switches, switching the keys 39 so that the phase of the signals from the standard | triggers to the inputs of logic elements 42-47 was replaced by 180 e. hail. At the same time, at the moment when the logic device 37 switches to one of its outputs, a logical zero appears briefly, which is fed to the input of the AND-NE 34 logic element. A logical unit appears at its output, which goes to the inputs of the first logic channel 29 - controls and inputs of similar circuit of other control channels. In this case, on their inputs, signals appear in accordance with the signals of sensor 9, the actuator, in accordance with them, the state of static triggers. If at the first moment after the logical zero at the input of the element 34 disappears, the signals at the output of the nullorgans 12-14 are zero, then the control angles of the inverter 2 thyristors are set in accordance with the sensor; and the composition of the rotor retains its value until the information arrives with zero organs. Similarly, information is updated at the input of static triggers and when changing the direction of rotation. In this case, if the rotational direction indicator switches through the node 35 of differentiating the fronts of the signals at the input of the logic element 34, a brief zero appears at the output, and a logical unit appears at the output, allowing the signals from the sensor 9 to pass through the input of static triggers. When the engine operates in high speed braking mode when adjusting the control angles of the inverter thyristors is required, for example: to limit the voltage at the output of the thyristors of the inverter 2 operating during deceleration in the accelerating mode (it should not exceed the counter-emf at the input of the controlled end a motor operating under braking in the inverter mode), at the output of the unit 55, comparing the actual speed level with the specified one, saves / - .- ,, with a logical zero, and at the output of the coincidence element 56 - a logical unit that torus does not affect the state of the static trigger 57. At the output of the operation mode determination unit 54, when the engine is braked, a logical unit is stored. When the speed in the brake system is lower than the set one, the logical unit appears at the output of the block 55, which is fed to the input of the coincidence element 56. If there are logical units at both of its outputs, a logical zero appears at its output, which enters the input of the static trigger 57 and switches it to the state when the logical one appears at the output of the logic element 64, and - logical zero. In this case, a logical unit appears at the output of logic element 34, allowing the signals of the sensor 9 of the position of the rotor to pass through the elements 29 and 30 of coincidence, to the input of the trigger 38, and at the output of the inverting logic element 58 there appears a logic zero. proceeding from phase-shifted signals from null-bodies 12-14 to trigger inputs 38. Further braking occurs with unregulated opening angles of the inverter thyristor d 0 (with respect to the intersection point of the phase EMF of the synchronous machine). If during braking a signal is received to accelerate the motor in another direction, then after reducing the speed to zero, the current in the phases of the synchronous machine remains the same, the torque on its shaft is also maintained, depending on the magnitude of the phase current and their relative position to the rotor. In this case, the rotor tends to occupy such a position, when the moment becomes equal to zero, i.e. when the resultant axis of the two sections, it coincides with the axis of the magnetic poles of the inductor of the synchronous machine. Since the torque of the synchronous machine, which seeks to set the inductor in this position, coincides with the torque of the motor mode of the other direction, the rotor of the engine begins to turn in this direction. But it does not reach the neutral position, since the rotor position sensor gives a signal to turn on the other phases of the synchronous machine, but already at the falling edge of its signal, the duration of which is 180 h.grad. (for a different direction of rotation, it is the leading edge). Thus, the phase of the control signals from the rotor position sensor without additional switchings in the control pairs changes by 180 el. hail, relative to the phase emf of a synchronous machine, ha the operating mode of the synchronous machine automatically changes from brake to motor. When the rotor of the engine is rotated at a certain angle corresponding to the dead zone of the direction of rotation indicator indicator, the signal at its output changes, the signal at the output of the operation mode determination unit 54 changes from a logical unit to a logical Zero corresponding to the driving mode.

In this case, a logical unit appears at the output of coincidence element 56, which does not affect the state of static trigger 57, which, when a logical zero signal arrives at its other input, switches from differentiating chains to the position where the logical element 63 appears the unit, and at the output of the logical element 64, the logical zero. The prohibition of the passage of phase-controlled pulses to the input of the static trigger 38 is removed, and the prohibition of the passage of pulses from the rotor position sensor, which are not phase-controlled, appears. The reverse process is terminated and the engine continues to operate in a predetermined mode.

Claims (1)

Tactical trigger, the first input of which is connected to the outputs of the operating mode determination unit and the unit comparing the actual speed level with the specified one through the coincidence element, and the second input through the differentiating chains to the output of the rotor position sensor, the nepBbrii output of the static trigger is connected to the second / and upsets logical elements of coincidence of the first group, and the input output is connected with the second inputs of logical elements of coincidence of the second group, the first input of the operation mode determination unit is connected with the output of the direction indicator in ascheni, and its second input coupled to the output device open-circuit switching operation modes, the input unit sravneyi actual speed to a predetermined level associated with the chain by differentiating the output of the rotor position sensor. Thus, due to the use of newly introduced elements, the switching process of the control zones of the inverter motor of the valve motor occurs after changing the direction of rotation and coincides with the moment of output of the next control pulse to the inverter's thyristors in O, which excludes the possibility of connecting, at the moment of the transition of the motor speed to zero, sections of the synchronous machine that do not meet the specified direction of rotation. This reduces additional speed fluctuations and increases the reliability of operation of a valve electric motor. (Claim of a motor according to St. 970578, characterized in that, with a PURPOSE of reliability, a mode of operation mode is entered into it, a unit comparing the actual speed level with a given , match element and staA /