US 6,038,155 A · Three phase SCR rectifier bridge with soft start control IC

Abstract

A soft start circuit for controlling a rectifier circuit, the rectifier circuit for converting power from an AC source having one or more phases to DC power having an output voltage (Vo) from a Vo+ node to a Vo- node, the rectifier circuit including: (i) at least first and second rectifier legs coupled from the Vo- node to the Vo+ node, each rectifier leg including a diode and a silicon controlled rectifier (SCR), wherein anodes of the diodes are coupled to the Vo- node, cathodes of the diodes are coupled to anodes of the SCRs at AC input nodes, and cathodes of the SCRs are coupled to the Vo+ node; and (ii) a bus capacitor coupled from the Vo+ node to the Vo- node, the soft start circuit operable to control respective firing angles of the SCRs such that: (i) the output voltage substantially linearly ramps from a low initial value to a relatively high final value, and (ii) charge up currents into the bus capacitor are controlled.

Claims98

Dependent claims

(i) at least first and second rectifier legs coupled from the Vo- node to the Vo+ node, each rectifier leg including a diode and a silicon controlled rectifier (SCR), wherein anodes of the diodes are coupled to the Vo- node, cathodes of the diodes are coupled to anodes of the SCRs at AC input nodes, and cathodes of the SCRs are coupled to the Vo+ node;
and (ii) a bus capacitor coupled from the Vo+ node to the Vo- node, the soft start circuit operable to control respective firing angles of the SCRs such that:
(i) the output voltage substantially linearly ramps from a low initial value to a relatively high final value, and (ii) charge up currents into the bus capacitor are controlled.

A rectifier circuit for converting power from an AC source having one or more phases to DC power having an output voltage (Vo) from a Vo+ node to a Vo- node, the rectifier circuit comprising:

first, second and third rectifier legs coupled from the Vo- node to the Vo+ node, each rectifier leg including a diode and a silicon controlled rectifier (SCR), wherein anodes of the diodes are coupled to the Vo- node, cathodes of the diodes are coupled to anodes of the SCRs at AC input nodes, and cathodes of the SCRs are coupled to the Vo+ node;
a bus capacitor coupled from the Vo+ node to the Vo- node;
and
a soft start circuit operable to control respective firing angles of the SCRs such that:
(i) the output voltage substantially linearly ramps from a low initial value to a relatively high final value, and (ii) charge up currents into the bus capacitor are controlled.

2 more elements

(i) at least first and second rectifier legs coupled from the Vo- node to the Vo+ node, each rectifier leg including a diode and a latchable MOS gated switch, wherein anodes of the diodes are coupled to the Vo- node, cathodes of the diodes are coupled to one terminal of the latchable MOS gated switches at AC input nodes, and another terminal of the latchable MOS gated switches are coupled to the Vo+ node;
and (ii) a bus capacitor coupled from the Vo+ node to the Vo- node, the soft start circuit operable to control respective firing angles of the latchable MOS gated switches such that:
(i) the output voltage substantially linearly ramps from a low initial value to a relatively high final value, and (ii) charge up currents into the bus capacitor are controlled.

Dependencies are inferred from the claim text.

Three phase SCR rectifier bridge with soft start control IC

Life of this patent

Three phase SCR rectifier bridge with soft start control IC

Life of this patent

Abstract

Claims98