Method for controlling asynchronous machines

Claim 2

Apparatus for controlling an inverter-fed asynchronous machine, comprising a component converter having two adding amplifiers each having two inputs and four multipliers each having two inputs and an output, each output of the multipliers being connected to a corresponding input of the amplifiers, a first input terminal connected to an input of each of two of said multipliers for applying a stator related field component voltage cos phi thereto, a second input terminal connected to an input of each of the other two of said multipliers for applying a stator related field component voltage sin phi thereto, a third input terminal connected to the other input of each of two of said multipliers for applying a field axis related voltage b or a stator related component voltage Ir thereto, and a fourth input terminal connected to the other input of each of the other two of said multipliers for applying a field axis related voltage w or a stator related component voltage Ij thereto.

Claim 3

Apparatus as claimed in claim 1, further comprising a vector analyzer having a pair of inputs and a pair of outputs connected to the first and second input terminals of said component converter, said vector analyzer having two amplifiers each having an input and an output and two multipliers, each of the amplifiers having a feedback circuit which includes a corresponding one of the multipliers, a first input terminal connected to the input of one of the amplifiers for applying a stator related field component psi r thereto, a second input terminal connected to the input of the other of the amplifiers for applying a stator related field component psi j thereto, two additional multipliers each having an output and an input connected to the output of a corresponding one of the amplifiers for squaring the output voltage of the corresponding amplifier, and an integrator having an input coupled to the outputs of the additional multipliers and an output connected to an input of each of said two multipliers for adding the squared output voltages of the amplifiers and comparing the resultant sum with a constant magnitude.

Claim 4

Apparatus as claimed in claim 2, wherein one side of the output of the integrator of the vector analyzer is limited to zero.

Claim 5

Apparatus as claimed in claim 2, further comprising an angular velocity measuring component having a pair of inputs connected to the outputs of said vector analyzer and an output coupled to inputs of said component converter, said angular velocity measuring component having a pair of differential components each having an input and an output, a pair of multipliers each having an input connected to the output of a corresponding one of the differential components, another input and an output, a first input terminal connected to the input of one of the differential components and to the other input of the multiplier connected to the other differential component for applying a stator related field component voltage cos phi thereto, a second input terminal connected to the input of the other of the differential components and to the other input of the multiplier connected to the other differential component for applying a stator related field component voltage sin phi thereto, a summation amplifier having an output and a pair of inputs each coupled to the output of a corresponding one of the multipliers for subtractively combining the outputs of said multipliers, and an output terminal connected to the output of the summation amplifier.

Claim 6

Apparatus as claimed in claim 2, further comprising an additional vector analyzer having outputs and a pair of inputs connected to outputs of said component converter, said additional vector analyzer producing output component voltages cos Beta * and sin Beta * at two of its outputs, a current regulator having a datum value input connected to a third output of said additional vector analyzer for an intermediate DC current Igl, an inverter having control means, and an angular switching circuit having inputs coupled to the two of the outputs of the additional vector analyzer and outputs connected to the control means of the inverter.

Claim 7

Apparatus as claimed in claim 5, wherein said angular switching circuit comprises a plurality of amplifiers having outputs and inputs connected to outputs of the additional vector analyzer for producing a plurality of AC voltages shifted by 60* relative to each other, a plurality of critical value indicators each having an input connected to the output of a corresponding one of said amplifiers and a plurality of AND gates each having two inputs connected to the outputs of corresponding ones of said critical value indicators and an output connected to the control means of the inverter.

Claim 8

Apparatus as claimed in claim 5, further comprising a phase correction regulator having inputs connected to the outputs of the additional vector analyzer and outputs connected to the inputs of the angular switching circuit for connecting the angular position of the stator current vector.

Claim 9

Apparatus as claimed in claim 7, wherein said phase correction regulator comprises an integrator having an input and an output, input means for applying to the input of the integrator a magnitude dependent upon the angular difference between a control vector determined by the component voltage cos Beta * and sin Beta * at the outputs of the additional vector analyzer and the stator current vector, and phase rotating means for rotating the control vector which is supplied to the input of the angular switching circuit, said phase rotating means having an input connected to the output of the integrator, other inputs and outputs, said phase rotating means comprising a pair of multipliers each having a pair of inputs and an output and an inverter amplifier having an input connected to an input of said phase correction regulator and an output connected to an input of one of the multipliers, an input of each of the multipliers being connected to the output of the integrator.

Claim 10

Apparatus as claimed in claim 8, wherein said phase correction regulator further comprises an additional pair of multipliers each having a pair of inputs and an output, an input terminal connected to an input of one of the additional multipliers multipliers for applying a voltage IS proportional to the stator phase current, thereto, an input terminal connected to an input of the other of the additional multipliers for applying a voltage IR proportional to the stator phase current, means coupling the inputs of the phase correction regulator to the other input of each of the additional multipliers for applying thereto AC voltages IR* and IS* formed from the component voltage cos Beta * and sin Beta * of the control vector, and a summation amplifier having a pair of inputs each connected to an output of a corresponding one of the additional multipliers and an output coupled to the input of the integrator, the output voltages of the additional multipliers being subtractively supplied to the summation amplifiers.

Claim 11

Apparatus as claimed in claim 8, wherein the phase correction regulator further comprises a phase angle measuring circuit having an output coupled to the input of the integrator and a pair of inputs, an input terminal connected to an input of the phase angle measuring circuit for applying a voltage IR proportional to the stator phase current thereto, and an input terminal connected to the other input of the phase angle measuring circuit for applying an AC voltage IR* derived from the component voltages cos Beta * and sin Beta * of the control vector thereto.

Claim 12

Apparatus as claimed in claim 9, wherein the phase correction regulator further comprises a third additional multiplier having an input coupled to the output of the summation amplifier, an output conNected to the input of the integrator and another input, and an input terminal connection to the other input of the third additional multiplier for supplying a magnitude phi proportional to the angular velocity of the field thereto.

Claim 13

Apparatus for controlling an inverter-fed asynchronous machine, comprising a harmonic-free two-phase generator for in-phase smoothing of field component voltages, said generator having an input and a pair of outputs, a PI regulator having an input and an output connected to the input of said generator for controlling the frequency of said generator, and input means connected to the input of the PI regulator for applying thereto a magnitude dependent upon the difference between the phase angle epsilon of an input vector E and the phase angle Alpha of a vector produced by said generator.

Claim 14

Apparatus for controlling an inverter-fed asynchronous machine, comprising a harmonic-free two-phase generator for in-phase smoothing of field component voltages, said generator having an input and a pair of outputs, a PI regulator having an input and an output connected to the input of said generator for controlling the frequency of said generator, and input means connected to the input of the PI regulator for applying thereto a magnitude dependent upon the difference between the phase angle epsilon of an input vector E and the phase angle Alpha of a vector produced by said generator.

Claim 15

Apparatus as claimed in claim 12, wherein one input of the divider is the divisor input and the other input of the divider is the dividend input and only positive magnitudes of the summation amplifier output voltage are applied to the divisor input of said divider.

Claim 16

Apparatus as claimed in claim 13, further comprising a pair of Zener diodes connected in series in opposing polarities between the output of the divider and the input of said generator.

Claim 17

Apparatus as claimed in claim 13, further comprising means coupled to the input of said generator for providing a magnitude dependent upon the angular velocity of the vector E for increasing the disturbance quantity of said generator.

Claim 18

Apparatus as claimed in claim 13, further comprising a pair of additional multipliers each having a pair of inputs and an output, smoothing means coupling the output of the summation amplifier applied to the divisor input of the divider to an input of each of the additional multipliers, an output of said generator being connected to the other input of one of the additional multipliers and the other output of said generator being connected to the other input of the other of the additional multipliers.

Claim 19

Apparatus as claimed in claim 16, wherein said apparatus is adapted to synchronize a power supply.

Claim 20

Apparatus as claimed in claim 16, wherein said apparatus is adapted to smooth the synchronizing voltage of control units for phase angle controlled rectifiers.

Claim 21

Apparatus for controlling an inverter-fed asynchronous machine, comprising a harmonic-free two phase generator for inphase smoothing of field component voltages, said generator having an input and a pair of outputs, a PI regulator having an input and an output connected to the input of said generator for controlling the frequency of said generator, and input means connected to the input of the PI regulator for applying thereto a magnitude dependent upon the difference between the phase angle of an input vector and the phase angle of a vector produced by said generator, said generator comprising two integrators and two multipliers connected in series circuit arrangement with one of said multipliers connected to the input of said generator, followed by one of said integrators, the other of said multipliers and the other of said integrators.

Claim 22

Apparatus for controlling an inverter-fed asynchronous machine, comprising a harmonic-free two phase generator for inphase smoothing of field component voltages, said generator having an input and a pair of outputs, a PI regulator having an input and an output connected to the input of said generator for controlling the frequency of said generator, and input means connected to the input of the PI regulator for applying thereto a magnitude dependent upon the difference between the phase angle of an input vector and the phase angle of a vector produced by said generator, said generator comprising two integrators and two multipliers connected in series circuit arrangement with one of said multipliers connected to the input of said generator, followed by one of said integrators, the other of said multipliers and the other of said integrators.

Claim 23

Apparatus for controlling an inverter-fed asynchronous machine, comprising a harmonic-free two phase generator for inphase smoothing of field component voltages, said generator having an input and a pair of outputs, a PI regulator having an input and an output connected to the input of said generator for controlling the frequency of said generator, input means connected to the input of the PI regulator for applying thereto a magnitude dependent upon the difference between the phase angle of an input vector and the phase angle of a vector produced by said generator, four multipliers each having two inputs and an output, one output of said generator being connected to an input of each of two of said multipliers and the other output of said generator being connected to an input of each of the other two of said multiplieRs, an input terminal connected to the other input of each of two of said multipliers for applying a vector component voltage thereto, an input terminal connected to the other input of each of the other two of said multipliers for applying a vector component voltage thereto, a pair of summation amplifiers each having a pair of inputs coupled to the outputs of corresponding ones of said multipliers and an output for producing output magnitudes proportional to the sine and cosine of a differential angle, and a divider having a pair of inputs each coupled to the output of a corresponding one of said summation amplifiers and an output for producing a magnitude proportional to the tangent of said differential angle.

Claim 24

Apparatus for controlling an inverter-fed asynchronous machine, comprising a harmonic-free two phase generator for inphase smoothing of field component voltages, said generator having an input and a pair of outputs, a PI regulator having an input and an output connected to the input of said generator for controlling the frequency of said generator, input means connected to the input of the PI regulator for applying thereto a magnitude dependent upon the difference between the phase angle of an input vector and the phase angle of a vector produced by said generator, four multipliers each having two inputs and an output, one output of said generator being connected to an input of each of two of said multipliers and the other output of said generator being connected to an input of each of the other two of said multiplieRs, an input terminal connected to the other input of each of two of said multipliers for applying a vector component voltage thereto, an input terminal connected to the other input of each of the other two of said multipliers for applying a vector component voltage thereto, a pair of summation amplifiers each having a pair of inputs coupled to the outputs of corresponding ones of said multipliers and an output for producing output magnitudes proportional to the sine and cosine of a differential angle, and a divider having a pair of inputs each coupled to the output of a corresponding one of said summation amplifiers and an output for producing a magnitude proportional to the tangent of said differential angle.

Claim 25

Apparatus for controlling an inverter-fed asynchronous machine, comprising a component converter (6) having a first pair of input terminals and a second pair of input terminals, voltage means connected to the first pair of input terminals for providing two DC voltages (b, w or I*w, I*b) determining two field axis related components of the stator current vector of the machine of which one is oriented in parallel and the other is oriented perpendicularly to the instantaneous rotary field axis of the machine, the component converter converting the field axis related components into corresponding stator related components of a datum value vector for the stator current, and field transmitting means connected to the second pair of input terminals for providing two component voltages (sin phi , cos phi ) defining the instantaneous portion of the rotary field axis.

Claim 26

Apparatus for controlling an inverter-fed asynchronous machine, comprising a component converter (6) having a first pair of input terminals and a second pair of input terminals, voltage means connected to the first pair of input terminals for providing two DC voltages (b, w or I*w, I*b) determining two field axis related components of the stator current vector of the machine of which one is oriented in parallel and the other is oriented perpendicularly to the instantaneous rotary field axis of the machine, the component converter converting the field axis related components into corresponding stator related components of a datum value vector for the stator current, and field transmitting means connected to the second pair of input terminals for providing two component voltages (sin phi , cos phi ) defining the instantaneous portion of the rotary field axis.

Claim 27

Apparatus as claimed in claim 21, further comprising a second component converter (21) having a first pair of input terminals, a second pair of input terminals and a pair of output terminals, transformation means connected to the first pair of input terminals for providing two component voltages (Ir, Ij) of the stator current vector, the field transmitting means being connected to the second pair of input terminals, and a pair of current regulators having pilot value inputs connected to the output terminals of the second component converter and outputs connected to the first pair of input terminals of the first component converter (6).

Claim 28

Apparatus as claimed in claim 22, wherein the voltage means comprises a speed regulator (110) providing an output signal which determines one of the field axis related stator current components (w or I*w).

Claim 29

Apparatus as claimed in claim 23, further comprising an angular velocity measuring component (27) having an output and a pair of multipliers (23, 24) having first inputs connected to the output (56) of the angular velocity measuring component and second inputs connected to the output terminals of the second component converter (21) and supplied by the second component converter with currents (Iw, Ib) proportional to the components of the stator current, and a pair of adding amplifiers connected to the multipliers for adding the output voltages of the multipliers to the component voltages of the datum value vector in a manner whereby a turning stretching of the datum value vector is effected in the rotary direction of the field of the machine and in dependence upon the stray field-time constant of the machine.

Claim 30

Apparatus as claimed in claim 24, further comprising a source of voltages (r, j), an additional pair of multipliers (23'', 24'') having first inputs connected to the output (56) of the angular velocity measuring component (27) and second inputs connected to the source of voltages, and outputs, and an additional pair of adding amplifiers connected to the outputs of the additional multipliers for adding the output voltages of the additional multipliers to the component voltages of the datum value vector in a manner whereby a turning stretching of the datum value vector is effected in opposition to the rotary direction of the field of the machine anD in dependence upon the main fieldtime constant of the machine.