Multiplex submersible pump telemetry system

Claim 2

In a pump installation having a power cable for delivering AC power from a power source at the surface to an AC motor located in a well, measuring means for monitoring at the surface physical parameters in the environment of the motor, comprising in combination: a downhole assembly located in the well in the vicinity of the motor and having a transmitter means for generating a carrier signal and for superimposing the carrier signal onto the power cable; switching means for switching the carrier signal on and off the power cable; a plurality of transducer means in the downhole assembly, each for providing a variable electrical response corresponding to a physical parameter of the motor environment; modulating means in the downhole assembly for providing controlling signals to the switching means to switch the carrier signal on for a duration corresponding to an electrical response of the transducer means; sequencing means in the downhole assembly for sequentially switching each of the transducer means separately into the modulating means to provide a carrier signal with envelopes of on duration corresponding to the electrical response of each of the transducer means; and conversion means at the surface for detecting the length of each envelope and for converting the length into readout signals proportional to the physical parameter.

Claim 3

In a pump installation having a power cable for delivering AC power from a power source at the surface to an AC motor located in a well, measuring means for monitoring at the surface physical parameters in the environment of the motor, comprising in combination: a downhole assembly located in the well in the vicinity of the motor and having a transmitter means for generating a carrier signal and for superimposing the carrier signal onto the power cable; switching means for switching the carrier signal on and off the power cable; a plurality of transducer means in the downhole assembly, each for providing a variable resistance corresponding to a physical parameter of the motor environment; modulating means in the downhole assembly for providing controlling signals to the switching means to switch the carrier signal on and off; sequencing means in the downhole assembly for sequentially switching each of the transducer means separately to the modulating means to provide the carrier signal with a pulse train of data envelopes, each data envelope being of duration corresponding to the resistance of each of the transducer means; synchronizing means in the downhole assembly for providing a synchronizing signal to the switching means to provide the carrier signal with a synchronizing envelope prior to each data envelope in the pulse train; and decoding means at the surface for detecting the synchronizing envelope and directing the data envelopes to respective readout means for converting the data envelopes into readout signals proportional to the parameter sensed.

Claim 4

In a pump installation having a power cable for delivering AC power from a power source at the surface to an AC motor located in a well, measuring means for monitoring at the surface physical parameters in the environment of the motor, comprising in combination: a downhole assembly located in the well in the vicinity of the motor and having a transmitter means for generating a carrier signal and for superimposing the carrier signal onto the power cable; switching means for switching the carrier signal on and off the power cable; a plurality of transducer means in the downhole assembly, each for providing a variable resistance corresponding to a physical parameter of the motor environment; modulating means in the downhole assembly for providing controlling signals to the switching means to switch the carrier signal on and off; sequencing means in the downhole assembly for sequentially switching each of the transducer means separately to the modulating means to provide the carrier signal with a pulse train of data envelopes, each data envelope being of duration corresponding to the resistance of each of the transducer means; synchronizing means in the downhole assembly for providing a synchronizing signal to the switching means to provide the carrier signal with a synchronizing envelope prior to each data envelope in the pulse train; and decoding means at the surface for detecting the synchronizing envelope and directing the data envelopes to respective readout means for converting the data envelopes into readout signals proportional to the parameter sensed.

Claim 5

In a pump installation having a power cable for delivering AC power from a power source at the surface to an AC motor located in a well, measuring means for monitoring at the surface physical parameters in the environment of the motor, comprising in combination: a downhole assembly located in the well in the vicinity of the motor and having a transmitter means for generating a carrier signal and for superimposing the carrier signal onto the power cable; switching means for switching the carrier signal on and off the power cable; a plurality of transducer means in the downhole assembly, each for providing a variable resistance corresponding to a physical parameter of the motor environment; a synchronizing resistor in the downhole assembly; modulating means in the downhole assembly for turning the switching mean on then off for a combined duration which corresponds to a resistance of each of the transducer means and also to the resistance of the synchronizing resistor; sequencing means in the downhole assembly for sequentially switching each of the transducer means and the synchronizing resistor separately to the modulating means to provide the carrier signal with data envelopes with on and off duration corresponding to the resistance of each of the transducer means and with a synchronizing envelope of on and off duration corresponding to the synchronizing resistor; and decoding means at the surface for detecting the synchronizing envelope and directing the data envelopes to respective readout means for converting the data envelopes into readout signals proportional to the parameter sensed.

Claim 6

In a pump installation having a power cable for delivering AC power from a power source at the surface to an AC motor located in a well, measuring means for monitoring at the surface physical parameters in the environment of the motor, comprising in combination: a downhole assembly located in the well in the vicinity of the motor and having a transmitter means for generating a carrier signal and for superimposing the carrier signal onto the power cable; switching means for switching the carrier signal on and off the power cable; a plurality of transducer means in the downhole assembly, each for providing a variable resistance corresponding to a physical parameter of the motor environment; a synchronizing resistor in the downhole assembly; modulating means in the downhole assembly for turning the switching mean on then off for a combined duration which corresponds to a resistance of each of the transducer means and also to the resistance of the synchronizing resistor; sequencing means in the downhole assembly for sequentially switching each of the transducer means and the synchronizing resistor separately to the modulating means to provide the carrier signal with data envelopes with on and off duration corresponding to the resistance of each of the transducer means and with a synchronizing envelope of on and off duration corresponding to the synchronizing resistor; and decoding means at the surface for detecting the synchronizing envelope and directing the data envelopes to respective readout means for converting the data envelopes into readout signals proportional to the parameter sensed.

Claim 7

In a pump installation having a power cable for delivering AC power from a power source at the surface to an AC motor located in a well, measuring means for monitoring at the surface physical parameters in the environment of the motor, comprising in combination: a downhole assembly located in the well in the vicinity of the motor and having a transmitter means for generating a carrier signal and for superimposing the carrier signal onto the power cable; switching means for switching the carrier signal on and off the power cable; a plurality of transducer means in the downhole assembly, each for providing a variable resistance corresponding to a physical parameter of the motor environment; modulating means in the downhole assembly for charging a capacitor, then discharging the capacitor through a synchronizing resistance to turn on and off the switching means for equal duration corresponding to the synchronizing resistance, to provide the carrier signal with a synchronizing envelope that has an on and off duration corresponding to the synchronizing resistance; downhole sequencing means in the downhole assembly for swithing each of the transducer means separately to the modulating means in place of the synchronizing resistance to provide the carrier signal with data envelopes with on and off duration corresponding to the resistance of the transducer means, the downhole sequencing means being triggered by the switching of the switching means; the synchronizing resistance being selected to provide a synchronizing envelope of duration less than the duration of any of the data envelopes; a plurality of readout means at the surface, each corresponding to one of the transducer means, for converting each of the data envelopes to a readout signal proportional to the parameter sensed; surface sequencing means at the surface for sequentially turning on each of the readout means for the duration of each of the data envelopes, the surface sequencing means being triggered by the receipt of one of the data envelopes; and synchronizing means at the surface for detecting the synchronizing envelope and for resetting the sequencing means upon receipt of the synchronizing envelope, to assure that each of the readout means is turned on by its respective data envelope.

Claim 8

In a pump installation having a power cable for delivering AC power from a power source at the surface to an AC motor located in a well, measuring means for monitoring at the surface physical parameters in the environment of the motor, comprising in combination: a downhole assembly located in the well in the vicinity of the motor and having a transmitter means for generating a carrier signal and for superimposing the carrier signal onto the power cable; switching means for switching the carrier signal on and off the power cable; a plurality of transducer means in the downhole assembly, each for providing a variable resistance corresponding to a physical parameter of the motor environment; modulating means in the downhole assembly for charging a capacitor, then discharging the capacitor through a synchronizing resistance to turn on and off the switching means for equal duration corresponding to the synchronizing resistance, to provide the carrier signal with a synchronizing envelope that has an on and off duration corresponding to the synchronizing resistance; downhole sequencing means in the downhole assembly for swithing each of the transducer means separately to the modulating means in place of the synchronizing resistance to provide the carrier signal with data envelopes with on and off duration corresponding to the resistance of the transducer means, the downhole sequencing means being triggered by the switching of the switching means; the synchronizing resistance being selected to provide a synchronizing envelope of duration less than the duration of any of the data envelopes; a plurality of readout means at the surface, each corresponding to one of the transducer means, for converting each of the data envelopes to a readout signal proportional to the parameter sensed; surface sequencing means at the surface for sequentially turning on each of the readout means for the duration of each of the data envelopes, the surface sequencing means being triggered by the receipt of one of the data envelopes; and synchronizing means at the surface for detecting the synchronizing envelope and for resetting the sequencing means upon receipt of the synchronizing envelope, to assure that each of the readout means is turned on by its respective data envelope.