A power system specifically adapted to provide DC power for powering a DC load at a remote site under severe environmental conditions, such as is found at remote gas pipeline locations. The power system includes a slow speed heat engine adapted to be powered by fuel, preferably taken directly from the gas pipeline, the supply of which is controlled by means of a pressure regulator. The engine is adapted to be directly coupled to an oversized, slow speed three-phase alternator so as to produce AC power, which is subsequently rectified to DC power output for powering a load in the range of 500 to 5,000 watts. The engine is particularly adapted to be started with a hand crank or a portable starter, and is provided with ceramic main bearings, an oversized lubrication system, redundant independent ignition systems and a highly superior cooling system. The cooling system includes a variable speed fan, the operation and speed of which is adapted to be automatically controlled in response to a sensed engine temperature for purposes of maintaining the engine temperature at a particular level. A rotary magnetic encoder system is provided for sensing the engine speed and for controlling the pressure regulator in response to the sensed speed to achieve optimum engine speed. Redundant safety shutdown systems are adapted to shut down the engine upon the occurrence of certain critical events. The remote power system is characterized by long life, minimal maintenance requirements and a mean time between failure equal to or in excess of 20,000 hours.
A brushless permanent magnet motor for use within a electric submergible pumping system is controlled without utilizing rotor position sensors, by sampling the voltage of the motor's windings. The operation of the motor is governed by control circuits that provide signals representative of the winding EMFs. The control circuits utilize an integrator, a offset corrector, and a crossover detector to simulate outputs received from Hall effect devices. Outputs from the control circuits are used to sequentially gate an array of commutation transistors to apply power to the different windings. These outputs are also used to develop a tachometer signal to regulate the speed of the motor, by controlling the supply voltage to the commutation transistors. Prior to starting the motor, the output bus voltage is permitted to rise from zero volts to a predetermined level. Then, the rotor rotates to a predetermined home position with regard to the stator. During this time, integrators are precharged to assist crossover detectors in establishing the initial timing relationship between the three motor phases. As the motor begins to rotate, the motor control is performed by detecting and processing winding EMFs, and operating the motor in a brushless D.C. mode.
A batteryless starting and ignition system for a conventional automotive internal combustion engine includes a battery replacement circuit which simulates the effect of an operational automotive lead-acid battery in the engine electrical circuit while the engine is running. A jumper cable connector is wired across the replacement circuit to facilitate jump starting of the engine. The system is particularly useful to replace automotive batteries in irrigation systems in which automotive engines are adapted to drive irrigation pumps continuously for periods up to six months.
An airtight rotating driving device with eccentricity, especially for volumetric pump, the device including a bent shaft (1) presenting an input axis (5) and an output axis (10) parallel and off-centered in such a way as to carry out an orbital circular movement, and an airtight and non-rotatable sleeve (14) surrounding the shaft and comprising two metallic bellows (19, 20) linked by a guiding ring (21) mounted longitudinally in a sliding relation on the sloped intermediate section (17) of the shaft. The device converts a rotating movement into an orbital circular movement with an absolute airtightness.
A backup generator located at a remote site provides the advantages of being compact in size but providing backup power over a long period of time. A multi-level cabinet which includes room for a backup generator and a fuel tank is located in close proximity to the electronic devices for which the power will be provided. The fuel tank may be used to hold propane or a similar fuel, and the tank will be included in a stacked structure with the backup generator. The cabinet for the generator includes sufficient structure to protect the electronics of the backup generator from the elements. Connected between the backup generator and a primary power source to the electronic devices, such as a personal communications system (PCS) site, is a sensor which detects when a power failure has occurred. In the event that such a failure has occurred, the backup generator is activated and provides power to the site electronics. Other monitoring equipment may be included with the backup generator so that its operation may be monitored from a remote location.
An electric motor that may be used in a remote location, such as in a wellbore for pumping production fluids. The electric motor is designed to permit real-time adjustment of the position feedback signals to optimize motor performance. A position sensor is coupled to the rotor to sense rotor position. Simultaneously, a parameter, such as shaft twist, is measured, and a feedback control signal is provided. A processor receives the position sensor signals and the feedback control signals, and adjusts the energization of the stator windings to optimize motor performance.
