An emulsion pump station is made up of mechanical drive unit, hydraulic head, pressure controller and emulsion box. The emulsion pump of mechanical drive unit is driven by an explosion-proof motor, which brings crankshaft to rotate via a shaft joint, and changes rotation motion of the crankshaft into straight reciprocating movement of plunger piston via linkage slider mechanism. In the application of an emulsion pump, parameters such as flow and pressure change as per applications. An emulsion pump often works at low load, and adjusts flow and pressure of emulsion by openness of valve at the port of pump. Its energy consumption is great, its impact on the machine (such as emulsion pump and valve) is great and it increases loss of the machine. Control requirement : Realize automatic control at constant pressure ; The system responds quickly, and able to realize real-time calculation for the system; Wide speed adjustment range and good soft start performance; Good overload capability and environment adaptability and high operating reliability as well; Wide input voltage scope and automatic adjustment of voltage. Solution: Electric drive condition: The frequency inverter drives explosion-proof motor and brings crankshaft to rotate via a shaft joint, and changes rotation motion of the crankshaft into straight reciprocating movement of plunger piston via linkage slider mechanism. Flow pressure is fed back to frequency inverter via pressure sensor and achieves constant pressure control of emulsion pump via PID control of frequency inverter; The system controls one 160KW explosion-proof asynchronous motor via one INVT CHV100A-01-160G-12 frequency inverter, rated flow: 200L/min,rated discharge pressure:30Mpa,pressure fluctuation:≤±1MPa and work point of relieve valve at about 30MPa and 31L/min;When feed fluid increases suddenly, discharge pressure drops, and frequency inverter increases rotation speed of the motor. When feed fluid decreases suddenly, discharge pressure rises, and frequency inverter reduces rotation speed of the motor. When the rotation speed drops to 210r/min, emulsion mainly flows back to the fluid box via relieve valve. With combined action of relieve valve and frequency inverter, discharge pressure of the system is stabilized at 30MPa. Advantage : Achieve automatic control at constant pressure and energy saving effect is obvious; Improve power factor at grid side and electric power utilization rate; Reduce use of relieve valve and reduce mechanical loss; Reduce mechanical impact and reduce maintenance amount of the equipment ±15% wide grid design meets power grid requirement in a poor environment.
Solution: Electric drive condition: The frequency inverter drives explosion-proof motor and brings crankshaft to rotate via a shaft joint, and changes rotation motion of the crankshaft into straight reciprocating movement of plunger piston via linkage slider mechanism. Flow pressure is fed back to frequency inverter via pressure sensor and achieves constant pressure control of emulsion pump via PID control of frequency inverter; The system controls one 160KW explosion-proof asynchronous motor via one INVT CHV100A-01-160G-12 frequency inverter, rated flow: 200L/min,rated discharge pressure:30Mpa,pressure fluctuation:≤±1MPa and work point of relieve valve at about 30MPa and 31L/min;When feed fluid increases suddenly, discharge pressure drops, and frequency inverter increases rotation speed of the motor. When feed fluid decreases suddenly, discharge pressure rises, and frequency inverter reduces rotation speed of the motor. When the rotation speed drops to 210r/min, emulsion mainly flows back to the fluid box via relieve valve. With combined action of relieve valve and frequency inverter, discharge pressure of the system is stabilized at 30MPa. Advantage : Achieve automatic control at constant pressure and energy saving effect is obvious; Improve power factor at grid side and electric power utilization rate; Reduce use of relieve valve and reduce mechanical loss; Reduce mechanical impact and reduce maintenance amount of the equipment ±15% wide grid design meets power grid requirement in a poor environment.