WO2004023636A1 - Apparatus and method for charging and discharging a capacitor to a predetermined setpoint - Google Patents
Apparatus and method for charging and discharging a capacitor to a predetermined setpoint Download PDFInfo
- Publication number
- WO2004023636A1 WO2004023636A1 PCT/US2003/023751 US0323751W WO2004023636A1 WO 2004023636 A1 WO2004023636 A1 WO 2004023636A1 US 0323751 W US0323751 W US 0323751W WO 2004023636 A1 WO2004023636 A1 WO 2004023636A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- smart material
- material actuator
- discharging
- charging
- voltage
- Prior art date
Links
- 238000007599 discharging Methods 0.000 title claims abstract description 28
- 238000000034 method Methods 0.000 title claims description 26
- 239000003990 capacitor Substances 0.000 title claims description 15
- 239000002520 smart material Substances 0.000 claims abstract description 50
- 230000004044 response Effects 0.000 claims description 16
- 239000011324 bead Substances 0.000 claims description 6
- 230000033228 biological regulation Effects 0.000 claims description 4
- 230000001629 suppression Effects 0.000 claims description 2
- 239000000463 material Substances 0.000 abstract description 5
- 230000004936 stimulating effect Effects 0.000 abstract description 2
- 238000006073 displacement reaction Methods 0.000 description 4
- 239000000919 ceramic Substances 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 230000010355 oscillation Effects 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 235000013361 beverage Nutrition 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000005669 field effect Effects 0.000 description 1
- 239000010408 film Substances 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 230000026280 response to electrical stimulus Effects 0.000 description 1
- 229910052715 tantalum Inorganic materials 0.000 description 1
- GUVRBAGPIYLISA-UHFFFAOYSA-N tantalum atom Chemical compound [Ta] GUVRBAGPIYLISA-UHFFFAOYSA-N 0.000 description 1
- 239000010409 thin film Substances 0.000 description 1
- 238000004804 winding Methods 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M3/00—Conversion of dc power input into dc power output
- H02M3/22—Conversion of dc power input into dc power output with intermediate conversion into ac
- H02M3/24—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters
- H02M3/28—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac
- H02M3/325—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal
- H02M3/335—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only
- H02M3/33569—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only having several active switching elements
- H02M3/33576—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only having several active switching elements having at least one active switching element at the secondary side of an isolation transformer
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M3/00—Conversion of dc power input into dc power output
- H02M3/22—Conversion of dc power input into dc power output with intermediate conversion into ac
- H02M3/24—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters
- H02M3/28—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac
- H02M3/325—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal
- H02M3/335—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only
- H02M3/33507—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only with automatic control of the output voltage or current, e.g. flyback converters
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M3/00—Conversion of dc power input into dc power output
- H02M3/22—Conversion of dc power input into dc power output with intermediate conversion into ac
- H02M3/24—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters
- H02M3/28—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac
- H02M3/325—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal
- H02M3/335—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only
- H02M3/3353—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only having at least two simultaneously operating switches on the input side, e.g. "double forward" or "double (switched) flyback" converter
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02N—ELECTRIC MACHINES NOT OTHERWISE PROVIDED FOR
- H02N2/00—Electric machines in general using piezoelectric effect, electrostriction or magnetostriction
- H02N2/0005—Electric machines in general using piezoelectric effect, electrostriction or magnetostriction producing non-specific motion; Details common to machines covered by H02N2/02 - H02N2/16
- H02N2/0075—Electrical details, e.g. drive or control circuits or methods
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N30/00—Piezoelectric or electrostrictive devices
- H10N30/80—Constructional details
- H10N30/802—Circuitry or processes for operating piezoelectric or electrostrictive devices not otherwise provided for, e.g. drive circuits
Definitions
- the present invention relates to electronic methods and circuits for controlling proportional general purpose smart material based actuators.
- Actuator technologies are being developed for a wide range of applications.
- One example includes a mechanically leveraged smart material actuator that changes shape in response to electrical stimulus. This change in shape is proportional to the input voltage. Since this shape change can be effectuated predominantly along a single axis, such actuators can be used to perform work on associated mechanical systems including a lever in combination with some main support structure. Changes in axial displacement are magnified by the lever to create an actuator with a useful amount offeree and displacement.
- Such force and displacement is useful for general-purpose industrial valves, clamps, beverage dispensers, compressors or pumps, brakes, door locks, electric relays, circuit breakers, and other applications actuated by means including solenoids, motors or motors combined with various transmission means.
- Smart materials, however, and piezoelectric materials specifically can require hundreds of volts to actuate and cause displacement. This type of voltage may not be readily available and may have to be derived from a lower voltage as one would find with a battery.
- piezoelectric materials are capacitive in nature. Moreover, a single actuator is often controlled using three separate signals: a control signal, a main supply and a ground.
- An apparatus for charging and discharging a capacitor to predetermined setpoints includes a smart material actuator and a voltage controlled direct current (DC) to DC converter for operating the smart material actuator in a proportional manner.
- the voltage controlled DC to DC converter can further include a self-oscillating drive circuit connected to a primary coil of a transformer with push- pull drive signals 180 degrees out of phase.
- the voltage controlled DC to DC converter can also include an auxiliary coil on the transformer.
- An attached diode rectifier to generate a DC voltage from an AC signal of the secondary coil on the transformer can also be included with the DC to DC converter as well as a voltage feedback network for voltage regulation.
- the voltage controlled DC to DC converter can further include control circuitry for stopping and starting the self-oscillating mechanism and can also feature a diode on an input stage for reverse polarity protection.
- control circuitry can further include a bead inductor and bypass capacitor for suppression of radiated EMI into the power source of the system.
- Another feature of the invention includes a smart material drive circuit for actively charging and discharging the smart material actuator in response to connecting and disconnecting a power source respectively.
- the drive circuit for actively controlling at least one of charging and discharging the smart material actuator can be responsive to a control signal.
- Yet another embodiment of the invention for charging and discharging a capacitor to predetermined setpoints includes a smart material actuator, a power source connectible to the smart material actuator, and a switch circuit for actively discharging the smart material actuator in response to removal of the connection to the power source.
- the switch circuit for actively charging the smart material actuator can further be responsive to connecting the power source or a control signal input.
- the switch circuit can actively control at least one of charging and discharging the smart material actuator in response to a control signal and can further include a voltage comparator and field effect transistor (FET) to control the DC to DC converter.
- the switch can, according to the invention, have three operational modes, charge load, hold load and discharge load.
- the method for charging and discharging a capacitor to predetermined setpoints includes the steps of providing a smart material actuator and operating the smart material actuator in a proportional manner with a voltage controlled DC to DC converter.
- An alternative method for charging and discharging a capacitor to predetermined setpoints according to the invention includes the steps of providing a smart material actuator, connecting a power source to the smart material actuator, and actively discharging the smart material actuator in response to removal of the connection to the power source with a switch circuit.
- Fig. 1 is an electronic schematic of a voltage controlled DC to DC converter with active regulation to which the present invention is applied;
- Fig. 2 is an electronic schematic of a DC to DC converter of the present invention
- Fig. 3 is an electronic schematic of the electronic switch of the present invention illustrating current flow when the switch is closed;
- Fig. 4 is an electronic schematic of the electronic switch of the present invention illustrating current flow when the switch is open; and [0016] Fig. 5 is an electronic schematic of the control circuit of the present invention.
- Figure 1 shows an electronic schematic of a system 10 for controlling a proportional mechanically leveraged smart material actuator (not shown) including a specialized power source 12 coupled to switching circuitry 44 and control circuitry 64.
- the specialized power source
- the DC to DC converter 12 (12 is missing from Fig 2.) includes a supply voltage 14 connected to a bead inductor 16 which feeds reverse protection diode 18. Bead inductor 16 acts as a filter to remove noise generated by the collector of negative positive negative (NPN) transistor 20 connected to the supply voltage 14. NPN transistor 20 and NPN transistor 22 form a push-pull driver for transformer 24. Resistors 26, 28, 30, and 32 form a resistive voltage divider and set the basic bias points for NPN transistors 20 and 22.
- NPN negative positive negative
- Transformer 24 is wound not only with a primary coil 24a and a secondary coil 24b, but an auxiliary coil 24c.
- Auxiliary winding 24c, transformer 24, resistors 34, 36, 28, and capacitors 38, 40 form feedback means to cause oscillation on the base of NPN transistors 20, 22.
- Oscillation is 180 degrees out of phase between the two NPN transistors 20, 22 forming a self-oscillating push-pull transformer driver.
- the secondary coil 24b of transformer 24 is connected to rectifier 42. It should be noted that when the base of transistor 22 is grounded, the self- oscillating mechanism is stopped. When the ground is removed, the self-oscillating mechanism is restarted.
- switch circuitry 44 when commanded, is capable of actively controlling the voltage to the capacitive load.
- Control circuitry 64 monitors the control voltage and output voltage and makes the decision to turn on the DC to DC converter, or turn on the discharge switch, or hold the current voltage level at the capacitive load. Included in the system is means for forcing the capacitive load to ground should the supply voltage be removed.
- switching circuitry 44 is depicted isolated from the schematic of Figure 1 to better illustrate the operative features of the switching circuitry 44 when it is closed.
- switch 48 When switch 48 is closed, current flows from a power source 50 through switch 48 through bead inductor 52 charging the capacitive load 54. Also, current flows into resistive divider network 56 driving the NPN transistor 58 on, which turns NPN Darlington pair 60 off. The rate of charge is determined by the impedance of the power source and the capacitance of the load 54.
- Resistor 62 and NPN transistor 58 serve as a level translator between the switched power and control signal, so the switched power and control signal do not have to have the same voltage levels.
- switch 48 When switch 48 is open, no current flows from the power source 50. Also, current flows into resistive divider network 56 through switch 48 to ground, driving the NPN transistor 58 off, which turns NPN Darlington pair 60 on causing current flow through resistor 46 discharging capacitive load 54. The rate of discharge is determined by the value of resistor 46 and capacitive load 54. Resistor 62 and NPN transistor 58 serve as a level translator between the switched power and control signal so the switched power and control signal do not have to have the same voltage levels.
- control circuit 64 of Figure 1 is shown isolated to better illustrate the operative features of the circuit 64.
- Analog control voltage flows through resistor 66 and is clamped by Zener diode 68 at a preset voltage so as not to damage the input of operational amplifier 70.
- resistor 66 is part of resistive dividing network 72.
- the network 72 derives two voltages; one voltage is the reference to shut the DC to DC converter 12 down, the other, a reference to actively discharge the capacitive load.
- Operational amplifier 70 is used in a voltage comparator mode that is associated with the DC to DC converter 12 shutdown mode.
- Operational amplifier 74 is used in a voltage comparator mode and is associated with the active discharge mode.
- Resistors 76, 78, 80 form a second resistive voltage divider network. This network monitors the capacitive load voltage and derives the voltages that operational amplifiers 70, 74 compare to the reference voltages derived from resistors 66, 72. When the voltage at the plus terminal of operational amplifier 70 is greater than the minus, the output of the amplifier goes to the plus saturation state turning FET transistor 82 on causing the DC to DC converter to stop.
- the components have been chosen for their current carrying ability, voltage rating, and type.
- suitable components can include FET small signal, and power transistors, wire wound, thin film, and carbon comp resistors, ceramic, tantalum, and film capacitors, wound, and Low Temperature cofired ceramic (LTCC) transformers, or any combination of suitable components commonly used for high volume production.
- LTCC Low Temperature cofired ceramic
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Dc-Dc Converters (AREA)
Abstract
Description
Claims
Priority Applications (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
AU2003257010A AU2003257010A1 (en) | 2002-09-05 | 2003-07-30 | Apparatus and method for charging and discharging a capacitor to a predetermined setpoint |
EP03794449A EP1547233A1 (en) | 2002-09-05 | 2003-07-30 | Apparatus and method for charging and discharging a capacitor to a predetermined setpoint |
CA2495486A CA2495486C (en) | 2002-09-05 | 2003-07-30 | Apparatus and method for charging and discharging a capacitor to a predetermined setpoint |
JP2004534255A JP4421479B2 (en) | 2002-09-05 | 2003-07-30 | Apparatus and method for charging and discharging a capacitor to a predetermined set point |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US40846802P | 2002-09-05 | 2002-09-05 | |
US60/408,468 | 2002-09-05 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2004023636A1 true WO2004023636A1 (en) | 2004-03-18 |
Family
ID=31978620
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/US2003/023751 WO2004023636A1 (en) | 2002-09-05 | 2003-07-30 | Apparatus and method for charging and discharging a capacitor to a predetermined setpoint |
Country Status (6)
Country | Link |
---|---|
EP (1) | EP1547233A1 (en) |
JP (1) | JP4421479B2 (en) |
CN (1) | CN1701499A (en) |
AU (1) | AU2003257010A1 (en) |
CA (1) | CA2495486C (en) |
WO (1) | WO2004023636A1 (en) |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0641066A1 (en) * | 1993-08-27 | 1995-03-01 | Hamamatsu Photonics K.K. | Push-pull, resonant type switching power supply circuit |
US5479062A (en) * | 1992-08-04 | 1995-12-26 | Fujitsu Limited | Piezo actuator driving circuit |
WO2001022502A1 (en) * | 1999-09-17 | 2001-03-29 | Siemens Aktiengesellschaft | Device for controlling at least one capacitive actuator |
EP1139448A1 (en) * | 2000-04-01 | 2001-10-04 | Robert Bosch GmbH | Method and apparatus for regulating voltages and voltage gradients for driving piezoelectric elements |
EP1182341A1 (en) * | 2000-08-25 | 2002-02-27 | Renault | Controller for a ceramic piezoelectric device, particularly for an internal combustion motor injection actuator |
Family Cites Families (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3947747A (en) * | 1975-02-19 | 1976-03-30 | Pylon Electronic Development Company Ltd. | Regulated transistorized DC to DC converter and parallel operation of plurality of converters |
JPH04507481A (en) * | 1990-05-08 | 1992-12-24 | キャタピラー インコーポレイテッド | Piezoelectric actuator drive device |
DE19733560B4 (en) * | 1997-08-02 | 2007-04-05 | Robert Bosch Gmbh | Method and device for charging and discharging a piezoelectric element |
US5895998A (en) * | 1997-09-18 | 1999-04-20 | Raytheon Company | Piezoelectric drive circuit |
FR2796219B1 (en) * | 1999-07-09 | 2001-09-21 | Renault | DEVICE AND METHOD FOR CONTROLLING A PIEZOELECTRIC ACTUATOR |
-
2003
- 2003-07-30 CA CA2495486A patent/CA2495486C/en not_active Expired - Lifetime
- 2003-07-30 EP EP03794449A patent/EP1547233A1/en not_active Withdrawn
- 2003-07-30 CN CN03820972.1A patent/CN1701499A/en active Pending
- 2003-07-30 JP JP2004534255A patent/JP4421479B2/en not_active Expired - Fee Related
- 2003-07-30 AU AU2003257010A patent/AU2003257010A1/en not_active Abandoned
- 2003-07-30 WO PCT/US2003/023751 patent/WO2004023636A1/en active Application Filing
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5479062A (en) * | 1992-08-04 | 1995-12-26 | Fujitsu Limited | Piezo actuator driving circuit |
EP0641066A1 (en) * | 1993-08-27 | 1995-03-01 | Hamamatsu Photonics K.K. | Push-pull, resonant type switching power supply circuit |
WO2001022502A1 (en) * | 1999-09-17 | 2001-03-29 | Siemens Aktiengesellschaft | Device for controlling at least one capacitive actuator |
EP1139448A1 (en) * | 2000-04-01 | 2001-10-04 | Robert Bosch GmbH | Method and apparatus for regulating voltages and voltage gradients for driving piezoelectric elements |
EP1182341A1 (en) * | 2000-08-25 | 2002-02-27 | Renault | Controller for a ceramic piezoelectric device, particularly for an internal combustion motor injection actuator |
Non-Patent Citations (3)
Title |
---|
BIELAWSKI JOHN ET AL: "Low profile LTCC transformers", 2002 INTERNATIONAL SYMPOSIUM ON MICROELECTRONICS;DENVER, CO, UNITED STATES SEP 4-6 2002, vol. 4931, 2002, Proc SPIE Int Soc Opt Eng;Proceedings of SPIE - The International Society for Optical Engineering 2002, pages 76 - 80, XP002266192, Retrieved from the Internet <URL:http://www.electroscience.com/publications/IMAPS2002(1).pdf> [retrieved on 20031226] * |
HOW TO USE INDUCTOR TYPE EMI SUPPRESSION FILTERS, pages 23, XP002266191, Retrieved from the Internet <URL:http://www.murata.com/emc/knowhow/pdfs/te15ey/23e.pdf> [retrieved on 20031231] * |
See also references of EP1547233A1 * |
Also Published As
Publication number | Publication date |
---|---|
CA2495486A1 (en) | 2004-03-18 |
EP1547233A1 (en) | 2005-06-29 |
AU2003257010A1 (en) | 2004-03-29 |
JP4421479B2 (en) | 2010-02-24 |
JP2006512034A (en) | 2006-04-06 |
CN1701499A (en) | 2005-11-23 |
CA2495486C (en) | 2013-07-16 |
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