No-break AC power supply
First Claim
1. An uninterruptible power supply comprising a power transformer including a first primary winding, a second primary winding, and a secondary winding,signal sensing means coupled to said first primary winding and responsive to detect a signal amplitude below a desired normal amplitude threshold,generating means to generate a periodic power signal and being coupled to said second primary winding,power flow control means to selectively control power transfer from said first and second primary windings to said secondary winding includingfirst phase detection means to monitor a signal phase of said secondary winding,phase control means coupled to said first phase detection means and to said generating means and normally operative to align the phase of said periodic signal with said signal phase of said secondary winding,second phase detection means to monitor a signal phase of said first primary winding,said phase control means coupled to said second phase detection means and to said signal sensing means and operative in response to a signal amplitude below a desired normal amplitude detected by said signal sensing means to align the phase of said periodic signal with a signal of said first primary winding.
0 Assignments
0 Petitions
Accused Products
Abstract
An uninterruptable power supply supplies a regulated output by utilizing a ferroresonant transformer. Two independent inputs are connected to the transformer; one input is connected to a commercial AC line signal source, the other input is connected to a battery energized static inverter circuit. The AC line source normally supplies the output power. A phase control system monitors the phase of the regulated output signal and constrains the static inverter to run in phase with the output. The phase and magnitude of the AC line signal are monitored. If the magnitude of the AC line drops significantly, the static inverter is constrained to operate in phase with the AC line signal wherein the inverter and AC line both share to contribute power to the output load. If the AC line signal fails, the static inverter operates independently and supplies all of the output power to the load.
-
Citations
24 Claims
-
1. An uninterruptible power supply comprising a power transformer including a first primary winding, a second primary winding, and a secondary winding,
signal sensing means coupled to said first primary winding and responsive to detect a signal amplitude below a desired normal amplitude threshold, generating means to generate a periodic power signal and being coupled to said second primary winding, power flow control means to selectively control power transfer from said first and second primary windings to said secondary winding including first phase detection means to monitor a signal phase of said secondary winding, phase control means coupled to said first phase detection means and to said generating means and normally operative to align the phase of said periodic signal with said signal phase of said secondary winding, second phase detection means to monitor a signal phase of said first primary winding, said phase control means coupled to said second phase detection means and to said signal sensing means and operative in response to a signal amplitude below a desired normal amplitude detected by said signal sensing means to align the phase of said periodic signal with a signal of said first primary winding.
- 6. A no-break reserve energy system comprising, signal processing means including first and second input means and output means, isolation means to minimize circulating currents between said first and second input means, first sensing means to detect a first signal magnitude threshold at said first input, second sensing means to detect a second signal magnitude threshold at said first input less than said first signal magnitude threshold, third sensing means to monitor a signal phase at said first input means, fourth sensing means to monitor a signal phase at said output means, phase control means to control the signal phase at said second input to coincide with the signal phase detected by one of said third and fourth sensing means, control selection means responsive to said first and second sensing means to selectively couple said third and fourth sensing means to said phase control means when signals at said first input are between said first and second signal magnitude threshold and when said signals exceed said first threshold, respectively.
- 12. An uninterruptable power supply comprising, a ferroresonant transformer having a regulated output, first and second inputs connected to said transformer, said first input adapted to accept a commercial AC line signal, said second input adapted to accept a DC voltage energized static inverter circuit, phase control means including line signal phase detection means to detect the phase of said AC signal, signal magnitude monitoring means to monitor the magnitude of said AC signal, and output signal phase detection means to detect the phase of said regulated output, said phase control means constraining said static inverter to run in phase with said regulated output in response to said signal monitoring means if the magnitude of the AC signal is normal, wherein the AC signal supplies the output power and said phase control means constraining said static inverter to operate in phase with the AC line signal with the magnitude of the AC signal at a lower than normal value wherein the static inverter and AC line both share to contribute to said regulated output.
- 16. An uninterruptable power supply comprising, first means to accept an AC primary source of energy, second means to accept a DC reserve source of energy, output means, signal processing means to couple said first and second means to accept to said output means, said means to couple including means to isolate said first and second means to accept from each other, inverter means to generate an AC signal coupled to interconnect said second means to accept to said signal processing means, said inverter means being responsive to derive AC signals from a DC reserve source of energy, magnitude monitoring means to monitor the magnitude of an AC signal applied to said first means to accept for a normal level, a brownout level, and a failed level, first phase detection means to detect the phase of a signal at said output means, second phase detection means to detect the phase of a signal at said first means to accept, means responsive to said magnitude monitoring means to constrain said inverter means to operate in phase with a signal phase detected by said first phase detection means at a normal level, and operate in phase with a signal detected by said second phase detection means at a brownout level, and to operate independently of said first and second phase detection means at a failed level.
- 20. A no-break uninterruptable power supply system comprising, a transformer including a saturating core, first and second primary windings, a secondary winding, a ferroresonant winding and a phase monitoring winding, controlled gating means connected to said first primary winding, means to accept an AC signal source connected to said gating means, an inverter circuit connected to said second primary winding, means to accept a DC signal source connected to said inverter circuit, first phase detection means coupled to said phase monitoring winding, second phase detection means coupled to said means to accept an AC signal, signal magnitude monitoring means connected to said means to accept an AC signal responsive to a normal, brownout, and failed magnitude of said AC signal, oscillating means having a phase adjustment circuit and connected to drive said inverter circuit, means to selectively couple said first and second phase detection means to said phase adjustment circuit, said means to selectively couple being responsive to said signal magnitude monitoring means to couple said first phase detection means to said phase adjustment circuit at a normal magnitude of said AC signal and couple said second phase detection means to said phase adjusment circuit at a brownout magnitude of said AC signal.
Specification