Patent ID: 7795824

Claim:
A linear motor automatic control circuit assembly connected to a 3-phase linear motor that is adapted for driving a submersible oil pump of a crude oil production system to pump crude oil out of an oil well, said linear motor automatic control circuit assembly comprising a linear motor power supply circuit, a CPU, an insulated gate bipolar transistor driving circuit, a current detection circuit, a fluid depth sensor, a function setting and status display circuit, and a circuit assembly power supply circuit, said linear motor power supply circuit being comprised of a 3-phase rectifier, a charging resistor, a filter and three insulated gate bipolar transistors and adapted to provide power supply to said linear motor, said insulated gate bipolar transistor driving circuit being electrically connected between said CPU and said insulated gate bipolar transistors of said linear motor power supply circuit and adapted for controlling on, off and speed of said linear motor, said current detection circuit being electrically connected between said CPU and current transformers at a front side of said linear motor power supply circuit and adapted for detecting the current value at said linear motor and providing the detected current value to said CPU for overcurrent protection control, said fluid depth sensor being electrically connected to said CPU and adapted for detecting the depth of the oil level in said oil well and providing the detected value to said CPU for reference in controlling the operation of said linear motor, said function setting and status display circuit being electrically connected to said CPU for setting system function parameters and displaying the settings and the status of the operation of the system, said circuit assembly power supply circuit providing the linear motor automatic control circuit assembly with the necessary working voltage.