Current-powered converted with energy recovery clamping circuit

• US 6,836,413 B2
• Filed: 06/17/2003
• Issued: 12/28/2004
• Est. Priority Date: 06/17/2002
• Status: Expired due to Term

• Current Assignee: ABB Schweiz AG (ABB Limited)
• Original Assignee: Magnetek Incorporated (Columbus Mckinnon Corporation)
• Inventors: Macerini, Sauro, Cincinelli, Lorenzo
• Primary Examiner(s): BERHANE, ADOLF D
• Application Number:
  US10/463,210
• Publication Number:
  US 20040042236A1
• Time in Patent Office: 560 Days
• Field of Search: 363/16, 363/17, 363/40, 363/55, 363/56.01, 363/131, 363/132
• US Class Current: 363/16
• CPC Class Codes: H02M 1/38 Means for preventing simultaneous conduction of switches
• CPC Class Codes: H02M 3/28 using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac
• CPC Class Codes: H02M 7/48 using discharge tubes with control electrode or semiconductor devices with control electrode

Abstract

A current-powered converter includes a current source, a switching section connected to the output of the converter, a dispersed inductance being provided between the switching section, and the converter output. A clamping circuit limits the voltage at the input of the switching section. The clamping circuit comprises a capacitor in which energy is stored during at least one phase of the switching cycle of the switching section, and an inductance by means of which the energy stored in said capacitor is returned to the output of the converter.

Claims

1. A current-powered converter comprising:

a current source;

a switching section connected to an output of the converter, a dispersed inductance being provided between the switching section and the converter output;

a clamping circuit operative to limit a voltage at an input of the switching section; and

said clamping circuit comprising a capacitor in which energy is stored during at least one phase of a switching cycle of said switching section, and an inductance by means of which the energy stored in said capacitor is returned to the output of the converter.

2. The converter according to claim 1 further comprising a transformer connected to the output of the converter, the transformer having a dispersed inductance, and said switching section is connected to the transformer wherein said inductance comprises the dispersed inductance of said transformer.

3. The converter according to claim 2 further comprising:

a first unidirectional component in series with said capacitor, said capacitor and said unidirectional component being arranged between a positive terminal and a negative terminal on an input side of said switching section; and

in parallel with said first unidirectional component, a controlled switch arranged in series with said inductance;

said controlled switch being closed when the switching section is in a phase where energy is transferred to the converter output and a capacitor voltage across said capacitor is at least equal to a reference voltage, and closing of said controlled switch connecting said capacitor to said inductance.

4. The converter according to claim 3, said first unidirectional component connecting the positive input terminal of the switching section to said capacitor when the input voltage of said switching section increases beyond said reference voltage.

5. The converter according to claim 4 further comprising a second unidirectional component in parallel with a circuit branch containing said controlled switch in series with said capacitor, said unidirectional component operative to prevent an over-voltage when the controlled switch is opened.

6. The converter according to claim 5 further comprising

a switching circuit operatively coupled to said controlled switch, the switching circuit functional to prevent closing of said controlled switch until the capacitor voltage has reached a predetermined value;

after the capacitor voltage reaches the predetermined value, the switching circuit is operative to close and open said controlled switch depending on switching conditions of the switching section, causing closing of the controlled switch when the switching section transfers energy to the converter output and keeping the controlled switch open when the switching section does not transfer energy to the converter output.