US4363060A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Arcless tap changer for voltage regulator
Assignee: Siemens Power Transmission and Distribution Inc
•
Filing: 1981-12-18
•
Granted: 1982-12-07
•
Expires: 2001-12-18
Abstract
Abstract A tap changer voltage regulator permits a tap changer selector contact to engage an open circuited new tap without arcing and has a half-tap voltage auxiliary winding which permits halving the inter-tap voltage to thus double the number of steps, and an auxiliary switch with a pair of movable contacts. A first auxiliary contact initially connects a selector contact which has moved to a new tap through a circulating current limiting resistor to a load, preventing load current interruption. A second auxiliary contact is in series with a normally-closed switch through which load current and circulating current flow. A first set of inverse parallel SCR's is in series with the resistor, while the normally-closed switch is shunted by a second pair of inverse parallel thyristors. The first pair of thyristors is not gated until the first auxiliary contact has attained its new position, precluding initial arcing. The normally-closed switch is then opened to transfer the current to the thyristors, and gating current is subsequently removed from the second pair of thyristors so that load and circulating current are statically interrupted by the thyristors at current zero, thus completing the tap change by permitting the second auxiliary contact to arclessly interrupt the circuit to the selector contact on the previous tap.
Inventors
- 👤 Frederick A. Stich
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 21:11
CPC Classifications
H; H01; H01H; H01H9/00; H01H9/0005; H01F; H01F29/00; H01F29/02; H01F29/04; H01H9/54; H01H9/548
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
192 words
In a power line voltage regulator of the tap changing type including a main winding and a tapped auxiliary winding, a plurality of taps on said auxiliary winding, a pair of selector contacts for engaging the taps, a collector coupled to each selector contact, drive means for operating said selector contacts and an output terminal adapted to be coupled to a load, the improvement comprising an auxiliary system for effecting arcless engagement and disengagement of said taps by said selector contacts including first and second terminals coupled to the first and second collectors, respectively; a first selector switch for engaging one or the other of said terminals; a current switch coupled between said selector switch and said output terminal; a first thyristor circuit coupled in shunt about said current switch; a gating circuit coupled to said thyristor circuit for energizing said thyristor circuit to allow said current switch to open arclessly; current limiting impedence means; means for electrically coupling said impedance means to one of said first or second terminals and circuit switching means for coupling said impedence means in circuit between said output terminal and said first or said second collectors.
Claim 2
Dependent Claim
192 words
In a power line voltage regulator of the tap changing type including a main winding and a tapped auxiliary winding, a plurality of taps on said auxiliary winding, a pair of selector contacts for engaging the taps, a collector coupled to each selector contact, drive means for operating said selector contacts and an output terminal adapted to be coupled to a load, the improvement comprising an auxiliary system for effecting arcless engagement and disengagement of said taps by said selector contacts including first and second terminals coupled to the first and second collectors, respectively; a first selector switch for engaging one or the other of said terminals; a current switch coupled between said selector switch and said output terminal; a first thyristor circuit coupled in shunt about said current switch; a gating circuit coupled to said thyristor circuit for energizing said thyristor circuit to allow said current switch to open arclessly; current limiting impedence means; means for electrically coupling said impedance means to one of said first or second terminals and circuit switching means for coupling said impedence means in circuit between said output terminal and said first or said second collectors.
Claim 3
Dependent Claim
101 words
The improvement according to claim 1, wherein said means for electrically coupling comprises a second selector switch for engaging one or the other of said terminals and said circuit switching means comprises a second thyristor circuit coupled in series with said current limiting impedence means; and a second gating circuit coupled to said second thyristor circuit for enabling said thyristor circuit when said second selector switch changes position, whereby load current is temporarily conducted through said second selector switch, current limiting impedence and second thyristor circuit while said first selector switch is moved from one of said terminals to the other.
Claim 4
Dependent Claim
35 words
The improvement according to claim 2, further including a current transformer coupled to a line in series with said current switch; means for applying the output of said current transformer to said first gating circuit.
Claim 5
Dependent Claim
35 words
The improvement according to claim 3, further including an auxiliary winding electromagnetically linked to said tapped winding and coupled in series between one of said collectors and one of said therefore first or second terminals.
Claim 6
Dependent Claim
90 words
The improvement according to claim 1, wherein said current limiting impedence comprises a first resistor and a second resistor; said means for electrically coupling comprises a first conductor coupling said first terminal to said first resistor and a second conductor coupling said second terminal to said second resistor; said circuit switching means comprises a second thyristor circuit coupled in series with said second resistor and a third thyristor circuit coupled in series with said first resistor; and a second gating circuit for enabling said first or said second thyristor circuit.
Claim 7
Dependent Claim
32 words
The improvement according to claim 5, further including an auxiliary winding magnetically coupled to said tapped winding and coupled in series between one of said collectors and said second current limiting resistor.
References Cited (Backward Citations)
US3515980A
Cited
US3621374A
Cited
US3621375A
Cited
US3786337A
Cited
US4130789A
Cited
US4201938A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-12-06 | 1986-06-07 | 1986-12-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-12-06 | 1990-06-07 | 1990-12-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-12-06 | 1994-06-07 | 1994-12-07 | $7700.00 | Window Closed / Lapsed |