Pump system including a variable frequency drive controller

Abstract

A pump system generally comprising an electrical connector operable to couple with an electric circuit to receive electricity, an electric motor operable to actuate a pump to pump a fluid, and a variable frequency drive (VFD) controller. The VFD controller is operable to control the rotational speed of the electric motor by providing a variable frequency signal to the electric motor to prevent the current utilized by the electric motor from exceeding a maximum current level associated with the electric circuit.

1 . A pump system comprising:
 an electrical connector operable to couple with an electric circuit to receive electricity;   an electric motor operable to actuate a pump to pump a fluid; and   a variable frequency drive (VFD) controller coupled with electric motor and connector, the VFD controller operable to control the rotational speed of the electric motor by providing a variable frequency signal to the electric motor to prevent the current utilized by the electric motor from exceeding a maximum current level associated with the electric circuit.   
   
   
       2 . The system of  claim 1 , further including a maximum current input coupled with the VFD controller, the maximum current input operable to be functioned to set the maximum current level. 
   
   
       3 . The system of  claim 1 , further including a voltage sensor operable to monitor the voltage provided by the electric circuit, the VFD controller being coupled with the voltage sensor and operable to calculate an available current level associated with the electric circuit and control the rotational speed of the electric motor to prevent the current utilized by the electric motor from exceeding the calculated available current level. 
   
   
       4 . The system of  claim 1 , further including a rotational speed input operable to be functioned to set a rotational speed, the VFD controller being coupled with the rotational speed input and operable to control the rotational speed of the electric motor to match the set rotational speed while preventing the current utilized by the electric motor from exceeding the maximum current level. 
   
   
       5 . The system of  claim 1 , further including—
 a mode input operable to be functioned to select an automatic mode or a manual mode, and   an output sensor operable to sense a characteristic of the pumped fluid,   the VFD controller being coupled with the mode input and output sensor and, if the automatic mode is selected, control the rotational speed of the electric motor based upon the sensed characteristic while preventing the current utilized by the electric motor from exceeding the maximum current level.   
   
   
       6 . The system of  claim 5 , wherein the sensed characteristic is a pressure of the pumped fluid and the VFD controller is operable to control the rotational speed of the electric motor to produce a generally constant pumped fluid pressure while preventing the current utilized by the electric motor from exceeding the maximum circuit current level. 
   
   
       7 . The system of  claim 1 , further including a filtering element operable to at least partially filter the pumped fluid. 
   
   
       8 . The system of  claim 1 , further including a wheeled cart, the electrical connector, electric motor, and VFD controller being mounted on the cart. 
   
   
       9 . A pump system comprising:
 an electrical connector operable to couple with an electric circuit to receive electricity therefrom;   a maximum current input operable to be functioned to set a maximum circuit current level;   a mode input operable to be functioned to select an automatic mode or a manual mode;   a pump;   an electric motor operable to actuate the pump to pump a fluid;   an output sensor operable to sense a characteristic of the pumped fluid; and   a variable frequency drive (VFD) controller coupled with the inputs, output sensor, and electric motor, the VFD controller operable to control the rotational speed of the electric motor by providing a variable frequency signal to the electric motor to prevent the current utilized by the electric motor from exceeding the set maximum circuit current level and, if the automatic mode is selected, control the rotational speed of the electric motor based upon the sensed characteristic.   
   
   
       10 . The system of  claim 9 , wherein the sensed characteristic is a pressure of the pumped fluid and the VFD controller is operable to control the rotational speed of the electric motor to produce a generally constant pumped fluid pressure while preventing the current utilized by the electric motor from exceeding the set maximum circuit current level. 
   
   
       11 . The system of  claim 9 , further including a rotational speed input operable to be functioned to set a rotational speed, the VFD controller being coupled with the rotational speed input and, if the manual mode is selected, control the rotational speed of the electric motor to match the set rotational speed while preventing the current utilized by the electric motor from exceeding the set maximum current level. 
   
   
       12 . The system of  claim 9 , further including a voltage sensor operable to monitor the voltage provided by the electric circuit, the VFD controller being coupled with the voltage sensor and operable to calculate an available current level associated with the electric circuit and control the rotational speed of the electric motor to prevent the current utilized by the electric motor from exceeding the calculated available current level. 
   
   
       13 . The system of  claim 8 , further including a filtering element, the pump being operable to pump the fluid through the filtering element to at least partially filter the fluid. 
   
   
       14 . The system of  claim 8 , further including a wheeled cart, the electrical connector, inputs, electric motor, and controller being mounted on the cart. 
   
   
       15 . A method of pumping a fluid, the method comprising:
 pumping a fluid using a electric motor powered by an electric circuit; and   controlling the rotational speed of the electric motor by providing a variable frequency signal to the electric motor to prevent the current utilized by the electric motor from exceeding a maximum current level associated with the electric circuit.   
   
   
       16 . The method of  claim 15 , further including acquiring the maximum current level associated with the electric circuit from a functionable input. 
   
   
       17 . The method of  claim 15 , further including monitoring the voltage provided by the electric circuit, calculating an available current level associated with the electric circuit, and controlling the rotational speed of the electric motor to prevent the current utilized by the electric motor from exceeding the calculated available current level. 
   
   
       18 . The method of  claim 15 , further including acquiring a rotational speed input and controlling the rotational speed of the electric motor to match the acquired rotational speed while preventing the current utilized by the electric motor from exceeding the maximum current level. 
   
   
       19 . The method of  claim 15 , further including sensing a characteristic of the fluid pumped by the electric motor and controlling the rotational speed of the electric motor based upon the sensed characteristic while preventing the current utilized by the electric motor from exceeding the maximum current level. 
   
   
       20 . The method of  claim 19 , wherein the sensed characteristic is a pressure of the pumped fluid and the rotational speed of the electric motor is controlled to produce a generally constant pumped fluid pressure. 
   
   
       21 . The method of  claim 15 , further including pumping the fluid through a filtering element to at least partially filter the fluid.