Electronic configuration and control for acoustic standing wave generation

Abstract

Aspects of the disclosure are directed to an apparatus for separating a second fluid or a particulate from a host fluid. That apparatus comprises a flow chamber with at least one inlet and at least one outlet. A drive circuit configured to provide a drive signal to a filter circuit configured to receive the drive signal and provide a translated drive signal. An ultrasonic transducer is cooperatively arranged with the flow chamber, and transducer includes at least one piezoelectric element configured to be driven by the current drive signal to create an acoustic standing wave in the flow chamber. At least one reflector opposing the ultrasonic transducer to reflect acoustic energy.

What is claimed is: 
     
         1 . An apparatus for driving a variable impedance load, comprising:
 an electronic driver that includes an inverter configured to produce an RF output;   a control circuit coupled to the variable impedance load and to the driver and configured to control the driver to provide a drive signal for the load; and   the control circuit being configured to receive feedback signals from the load and control the driver based on a reactance value obtained from the feedback signals.   
     
     
         2 . The apparatus of  claim 1 , where the control circuit comprises a digital signal processor. 
     
     
         3 . The apparatus of  claim 1 , further comprising a compensation circuit between the driver and the load. 
     
     
         4 . The apparatus of  claim 3 , wherein the compensation circuit further comprises an inductive component and a capacitive component. 
     
     
         5 . The apparatus of  claim 1 , further comprising a DC-DC converter coupled to the control circuit and the inverter. 
     
     
         6 . An apparatus for driving an ultrasonic transducer at radio frequencies (RF), comprising:
 an electronic driver coupled to the ultrasonic transducer for exciting the ultrasonic transducer; and   a DC-DC converter and an inverter included in the driver.   
     
     
         7 . The apparatus of  claim 6 , further comprising a conversion circuit between the DC-DC converter and the inverter. 
     
     
         8 . The apparatus of  claim 7 , wherein the conversion circuit is configured to convert a PWM signal to a DC signal. 
     
     
         9 . The apparatus of  claim 6 , further comprising a scaling circuit that is configured to convert a voltage drive signal to a current drive signal. 
     
     
         10 . The apparatus of  claim 9 , wherein the scaling circuit consists of passive circuit components. 
     
     
         11 . The apparatus of  claim 6 , further comprising a controller coupled to the ultrasonic transducer and to the driver, the controller configured to receive feedback signals from the ultrasonic transducer and to control the driver in accordance with the feedback signals. 
     
     
         12 . A method for driving a variable impedance load, comprising:
 controlling an electronic driver that includes an inverter to produce an RF output to the load;   determining a control for the electronic driver based on feedback signals from the load; and   providing the control to the electronic driver to produce the RF output to the load.   
     
     
         13 . The method of  claim 12 , further comprising using a digital signal processor for determining the control. 
     
     
         14 . The method of  claim 12 , further comprising compensating the RF output to the load. 
     
     
         15 . The method of  claim 12 , further comprising converting the RF output from a voltage drive signal to a current drive signal. 
     
     
         16 . The method of  claim 12 , wherein the electronic driver further comprises a DC-DC converter; and
 driving the DC-DC converter to produce a power output to the inverter.