Electronic configuration and control for acoustic standing wave generation
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.
1. An apparatus for separating a second fluid or a particulate from a host fluid, comprising:
an ultrasonic transducer coupled to a flow chamber configured to house the host fluid;
an electronic driver coupled to the ultrasonic transducer for exciting the ultrasonic transducer to generate an acoustic standing wave in the flow chamber;
a control circuit coupled to the ultrasonic transducer and to the driver and configured to control the driver to provide a drive signal for the ultrasonic transducer; and
the control circuit being configured to receive feedback signals from the ultrasonic transducer 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 2 , where the acoustic standing wave comprises a multi-dimensional acoustic standing wave.
4. The apparatus of claim 1 , further comprising a compensation circuit between the driver and the ultrasonic transducer.
5. The apparatus of claim 4 , wherein the compensation circuit further comprises an inductive component and a capacitive component.
6. An apparatus for separating a secondary fluid or particulates from a host fluid, comprising:
an ultrasonic transducer coupled to a flow chamber configured to house the host fluid;
an electronic driver coupled to the ultrasonic transducer for exciting the ultrasonic transducer to generate an acoustic standing wave in the flow chamber; and
a DC-DC converter and an inverter included in the driver.
7. The apparatus of claim 6 , where the acoustic standing wave includes a multi-dimensional acoustic standing wave.
8. The apparatus of claim 6 , further comprising a scaling circuit that receives a drive signal from the driver and provides a translated drive signal to the ultrasonic transducer, where the scaling circuit provides impedance and source translation with respect to the ultrasonic transducer.
9. The apparatus of claim 8 , where the scaling circuit comprises a first inductor, a first capacitor and a second inductor cooperatively arranged as a low pass filter.
10. The apparatus of claim 8 , where the scaling circuit comprises an inductor that includes a first terminal and a second terminal, and a capacitor that includes a third terminal and a fourth terminal, where the first terminal receives the drive signal, the second and third terminals are connected, the fourth terminal is connected to a reference potential, and a signal indicative of the equivalent translated drive signal is provided at the second and third terminals.
11. The apparatus of claim 8 , wherein the scaling circuit consists of passive circuit components.
12. The apparatus of claim 6 , further comprising a conversion circuit between the DC-DC converter and the inverter.
13. 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.
14. The apparatus of claim 12 , where the conversion circuit comprises a low pass filter.
15. An apparatus for separating a second fluid or a particulate from a host fluid, comprising:
an ultrasonic transducer including a piezoelectric element and coupled to a flow chamber configured to house the host fluid;
a drive circuit coupled to the ultrasonic transducer and configured to provide a drive signal to the ultrasonic transducer to generate an acoustic standing wave in the flow chamber;
a controller coupled to the ultrasonic transducer and to the drive circuit and configured to control the drive circuit based on reactance values of the ultrasonic transducer.
16. The apparatus of claim 15 , where the acoustic standing wave comprises a multi-dimensional acoustic standing wave.
17. The apparatus of claim 15 , further comprising a compensation circuit between the driver and the ultrasonic transducer.
18. The apparatus of claim 15 , further comprising a DC-DC converter and an inverter in the drive circuit.
19. The apparatus of claim 18 , wherein the DC-DC converter is configured to provide a power signal and the inverter is configured to provide an RF signal based on the power signal.
20. The apparatus of claim 15 , where the controller is configured to detect reactance minima from feedback signals from the ultrasonic transducer.