Power meter disconnect switch operation
AssigneeElster Solutions, LLC
InventorKenneth C. Shuey
Life of this patent
Estimating the term…
Abstract
Techniques are disclosed herein for improved power meter disconnect switch operation, which may include opening and/or closing of the disconnect switch. In particular, for reasons such as reduction of electromechanical stress on the disconnect switch, the disconnect switch may be operated based, at least in part, on a voltage at the load side of the disconnect switch. For example, in some cases, the disconnect switch may be opened slightly before a zero crossover of a waveform corresponding to the load side voltage. As another example, in some cases, the disconnect switch may be closed slightly before or slightly after a zero crossover of a waveform corresponding to the load side voltage.
Claims17
A system for operating a disconnect switch based, at least in part, on a load side voltage in a power meter coupled to a voltage source through a first and second source side contacts, the power meter coupled to a load through a first and second load side contacts, the power meter measuring power flowing from the voltage source to the load, the system comprising:
- the disconnect switch interposed between the first source side contact and the first load side contact and between the second source side contact and the second load side contact, the disconnect switch interrupting a flow of power from the voltage source to the load when the disconnect switch is in an open position;
- a first bypass resistor coupled between the first source side contact and the first load side contact, a second bypass resistor coupled between the first source side contact and the second load side contact,
- a load side voltage sensor coupled to the first load side contact and the second load side contact, the load side voltage sensor measuring a first load side voltage from the first load side contact and measuring a second load side voltage from the second load side contact;
- and
- one or more processing components that perform operations comprising:
- receiving a request to close the disconnect switch;
- making a determination, based, at least in part, on the first load side voltage, of when to issue a command to close the disconnect switch, wherein the determination is based, at least in part, on a time selected for the disconnect switch to close, wherein the selected time is 1 millisecond or less prior or subsequent to an occurrence of a zero crossover of a waveform corresponding to the first load side voltage;
- and
- issuing the command to close the disconnect switch.
A system for operating a disconnect switch based, at least in part, on a load side voltage in a power meter coupled to a voltage source through one or more source side contacts, the power meter coupled to a load through one or more load side contacts, the power meter measuring power flowing from the voltage source to the load, the system comprising:
- the disconnect switch interposed between the one or more load side contacts and the one or more source side contacts, the disconnect switch interrupting a flow of power from the one or more source side contacts to the one or more load side contacts when the disconnect switch is in an open position;
- a load side voltage sensor that measures the load side voltage from at least one of the one or more load side contacts;
- and
- one or more processing components that perform operations comprising:
- receiving a request to open the disconnect switch;
- making a determination, based, at least in part, on the load side voltage, of when to issue a command to open the disconnect switch, wherein the determination is based, at least in part, on a time selected for the disconnect switch to open, wherein the selected time is 1 millisecond or less prior to an occurrence of a subsequent zero crossover of a waveform corresponding to the load side voltage;
- and
- issuing the command to open the disconnect switch.
A method for operating a disconnect switch based, at least in part, on a load side voltage in a power meter coupled to a voltage source through a first and second source side contacts, the power meter coupled to a load through a first and second load side contacts, the power meter measuring power flowing from the voltage source to the load, the method comprising:
- receiving a request to close the disconnect switch, wherein the disconnect switch is interposed between the first source side contact and the first load side contact and between the second source side contact and the second load side contact, the disconnect switch interrupting a flow of power from the voltage source to the load when the disconnect switch is in an open position;
- making a determination, based at least in part on a first load side voltage, of when to issue a command to close the disconnect switch, wherein a first bypass resistor is coupled between the first source side contact and the first load side contact, wherein a second bypass resistor is coupled between the first source side contact and the second load side contact, and wherein a load side voltage sensor is coupled to the first load side contact and the second load side contact, the load side voltage sensor measuring the first load side voltage from the first load side contact and measuring a second load side voltage from the second load side contact;
- issuing the command to close the disconnect switch;
- and
- closing the disconnect switch in response to the command to close the disconnect switch, wherein the disconnect switch is closed on a plurality of occasions, wherein, for at least some of the plurality of occasions, the disconnect switch is closed while a waveform corresponding to the first load side voltage is in a positive half cycle, and wherein, for at least some other of the plurality of occasions, the disconnect switch is closed while the waveform corresponding to the first load side voltage is in a negative half cycle.
Dependencies are inferred from the claim text.