Motor power supply system

Claim 2

A motor power supply system comprising, a motor having a polyphase winding and a rotor, a field winding for said motor operative when energized by direct current to provide magnetic poles on said rotor, a switching circuit comprised of a plurality of controlled rectifiers, said switching circuit having input terminals and output terminals connected with said polyphase motor winding, means for causing groups of said controlled rectifiers of said switching circuit to be gated conductive in a predetermined sequence as a function of rotor position to thereby provide current paths for energizing said polyphase winding in a predetermined polyphase sequence, each group of controlled rectifiers when gated conductive defining a full-wave rectifier circuit that is operative to apply a direct voltage to predetermined phases of said polyphase winding, the switching frequency of said controlled rectifiers being a function of rotor speed, a source of direct voltage, inverter means having an input connected to said source of direct voltage and having an output circuit, said inverter means providing a variable frequency alternating output voltage at its output circuit, a circuit connecting the output circuit of said inverter means to said input terminals of said switching circuit including coupling capacitor means connected in series between said inverter means and said switching circuit, means for varying the frequency of the alternating output voltage of said inverter means whereby the reactance of said coupling capacitor means is varied as a function of the output frequency of said inverter means to thereby control the amount of power supplied to said switching circuit from said inverter means, and means for energizing said field winding with direct current.

Claim 3

A motor power supply system comprising, a motor having a polyphase winding and a rotor, a field winding for said motor operative when energized with direct current to provide magnetic poles on said rotor, a switching circuit comprised of a plurality of controlled rectifiers, said switching circuit having input terminals and output terminals connected with said polyphase winding, means for causing groups of said controlled rectifiers of said switching circuit to be gated conductive in a predetermined sequence as a function of rotor position to thereby provide curreNt paths for energizing said polyphase winding in a predetermined polyphase sequence, each group of controlled rectifiers when gated conductive defining a full-wave rectifier circuit that is operative to apply a direct voltage to predetermined phases of said polyphase winding, the switching frequency of said controlled rectifiers being a function of rotor speed, a source of direct voltage, inverter means having an input circuit connected to said source of direct voltage and having an output circuit, said inverter means providing a variable frequency alternating output voltage at its output circuit, a circuit connecting the output circuit of said inverter means to said input terminals of said switching circuit including coupling capacitor means connected in series between said inverter means and said switching circuit, means for varying the frequency of the alternating output voltage of said inverter means whereby the reactance of said coupling capacitor means is varied as a function of the output frequency of said inverter means to thereby control the amount of power supplied to said switching circuit from said inverter means, and means including rectifier means connected between the input circuit to switching circuit and said field winding operative to energize said field winding with a direct voltage that is proportional to the input current to said switching circuit.

Claim 4

A motor power supply system comprising, a motor having a polyphase winding and a rotor, a field winding for said motor operative when energized with direct current to provide magnetic poles on said rotor, a switching circuit comprised of a plurality of controlled rectifiers, said switching circuit having input terminals and output terminals connected with said polyphase winding, means for causing groups of said controlled rectifiers of said switching circuit to be gated conductive in a predetermined sequence as a function of rotor position to thereby provide curreNt paths for energizing said polyphase winding in a predetermined polyphase sequence, each group of controlled rectifiers when gated conductive defining a full-wave rectifier circuit that is operative to apply a direct voltage to predetermined phases of said polyphase winding, the switching frequency of said controlled rectifiers being a function of rotor speed, a source of direct voltage, inverter means having an input circuit connected to said source of direct voltage and having an output circuit, said inverter means providing a variable frequency alternating output voltage at its output circuit, a circuit connecting the output circuit of said inverter means to said input terminals of said switching circuit including coupling capacitor means connected in series between said inverter means and said switching circuit, means for varying the frequency of the alternating output voltage of said inverter means whereby the reactance of said coupling capacitor means is varied as a function of the output frequency of said inverter means to thereby control the amount of power supplied to said switching circuit from said inverter means, and means including rectifier means connected between the input circuit to switching circuit and said field winding operative to energize said field winding with a direct voltage that is proportional to the input current to said switching circuit.

Claim 5

A motor power supply system comprising, a motor having a polyphase winding, a switching circuit comprised of a plurality of controlled rectifiers having input terminals and output terminals connected with said polyphase winding, said switching circuit sequentially energizing the phase windings of said polyphase winding in a predetermined sequence, a source of direct voltage, an inverter having an input connected to said source of direct voltage and having an output, said inverter developing a variable frequency output voltage at said output, means connecting the output of said inverter to the input terminals of said switching circuit including a first coupling capacitor, voltage developing means connected across the input terminals of said switching circuit for developing a voltage which is a function of the input voltage to said switching circuit, a second capacitor, means including a first rectifying circuit for charging said second capacitor from said voltage developing means, current responsive means for developing an alternating voltage which is a function of the input current to said switching circuit, and a second rectifying circuit connected to said current responsive means, the direct voltage output terminals of said second rectifying circuit being connected in series with said source of direct current and in series with said second capacitor.

Claim 6

A motor power supply system comprising, a motor having a polyphase winding, a switching circuit comprised of a plurality of controlled rectifiers having input terminals and output terminals connected with said polyphase winding, said switching circuit sequentially energizing the phase windings of said polyphase winding in a predetermined sequence, a source of direct voltage, an inverter having an input connected to said source of direct voltage and having an output, said inverter developing a variable frequency output voltage at said output, means connecting the output of said inverter to the input terminals of said switching circuit including a first coupling capacitor, voltage developing means connected across the input terminals of said switching circuit for developing a voltage which is a function of the input voltage to said switching circuit, a second capacitor, means including a first rectifying circuit for charging said second capacitor from said voltage developing means, current responsive means for developing an alternating voltage which is a function of the input current to said switching circuit, and a second rectifying circuit connected to said current responsive means, the direct voltage output terminals of said second rectifying circuit being connected in series with said source of direct current and in series with said second capacitor.

Claim 7

A motor power supply system comprising, a source of direct current, inverter means having an input connected to said source of direct current, said inverter means having an output providing an alternating voltage, means for varying the output frequency of the alternating voltage developed at the output of said inverter means, a motor having a polyphase winding and a rotor, said motor having a field winding for developing magnetic poles on said rotor, a switching circuit comprised of a plurality of controlled rectifiers having an input and output connected to said polyphase winding, means for causing said controlled rectifiers to become conductive in a predetermined sequence related to rotational position of said rotor to thereby control the energization of said polyphase winding, means connecting the output of said inverter means and the input of said switching circuit including a coupling capacitor, current transformer means operative to develop an alternating voltage which is proportional to the current passing through said coupling capacitor, rectifier means for rectifying said alternating voltage to a direct voltage, and means for applying said direct voltage to the field winding of said motor.

Claim 8

A motor power supply system comprising, a source of direct current, inverter means having an input connected to said source of direct current, said inverter means having an output providing an alternating voltage, means for varying the output frequency of the alternating voltage developed at the output of said inverter means, a motor having a polyphase winding and a rotor, said motor having a field winding for developing magnetic poles on said rotor, a switching circuit comprised of a plurality of controlled rectifiers having an input and output connected to said polyphase winding, means for causing said controlled rectifiers to become conductive in a predetermined sequence related to rotational position of said rotor to thereby control the energization of said polyphase winding, means connecting the output of said inverter means and the input of said switching circuit including a coupling capacitor, current transformer means operative to develop an alternating voltage which is proportional to the current passing through said coupling capacitor, rectifier means for rectifying said alternating voltage to a direct voltage, and means for applying said direct voltage to the field winding of said motor.