GB2301716A - Phase angle control circuit for a switching device - Google Patents

Phase angle control circuit for a switching device Download PDF

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Publication number
GB2301716A
GB2301716A GB9511076A GB9511076A GB2301716A GB 2301716 A GB2301716 A GB 2301716A GB 9511076 A GB9511076 A GB 9511076A GB 9511076 A GB9511076 A GB 9511076A GB 2301716 A GB2301716 A GB 2301716A
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United Kingdom
Prior art keywords
circuit
zero
passing
voltage
power source
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Application number
GB9511076A
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GB9511076D0 (en
Inventor
Tai-Her Yang
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Individual
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Individual
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Priority to GB9511076A priority Critical patent/GB2301716A/en
Publication of GB9511076D0 publication Critical patent/GB9511076D0/en
Publication of GB2301716A publication Critical patent/GB2301716A/en
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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
    • H02M5/00—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases
    • H02M5/02—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases without intermediate conversion into dc
    • H02M5/04—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases without intermediate conversion into dc by static converters
    • H02M5/22—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases without intermediate conversion into dc by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
    • H02M5/275—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases without intermediate conversion into dc by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal
    • H02M5/293—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases without intermediate conversion into dc by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only
    • 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
    • H02M5/00—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases
    • H02M5/02—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases without intermediate conversion into dc
    • H02M5/04—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases without intermediate conversion into dc by static converters
    • H02M5/22—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases without intermediate conversion into dc by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
    • H02M5/275—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases without intermediate conversion into dc by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal
    • H02M5/293—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases without intermediate conversion into dc by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only
    • H02M5/2932—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases without intermediate conversion into dc by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only with automatic control of output voltage, current or power
    • H02M5/2935—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases without intermediate conversion into dc by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only with automatic control of output voltage, current or power using reverse phase control, i.e. turn-on of switches in series with load at zero crossing of input voltage, turn-off before next zero crossing

Abstract

A phase angle control circuit for a switching device 103 comprises a zero crossing detector 101 for detecting the zero crossing of an ac or pulsed dc waveform from a power source 100 connectable by the switching device 103 to a load 105, a timing circuit 102 responsive to the zero crossing detector and controlling the switching device 103, a feedback circuit 107 for detecting a physical or chemical status of the load and a central controller 110 for controlling the timing circuit according to the feedback from the feedback circuit 103. The timing circuit 102 is coupled to the switching device 103 by a driving circuit 104. A compensation component 106, such as a flywheel diode, capacitor or current limiting resistor is coupled across the load. The switching device may be a solid state switch such as an IGBT or an electromechanical switch. The physical status detected by the feedback circuit 107 may be velocity, direction, torque, temperature or sound intensity. The load may be a rotational machine, lighting device or a resistive, inductive or capacitive load.

Description

PHASE SHIFT CUT-OFF CONTROL CIRCUIT SUMMARY OF THE INVENTION The phase shift cut-off control circuit is an innovative circuit to provide effective phase angle conduction, whereby to further control the output voltage of the AC or intermittent pulse DC power source, thereof it is characterized in that the AC voltage at the first zeropassing value (or at the neighborhood) is the trigger point, and the second zero-passing value is the cut-off point, i. e. phase shift control is performed between the electrical angle 00-1800 to modulate the output voltage.
BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is the schematic block diagram of the invention illustrating the main circuit composition.
Figure 1-1 is a schematic diagram illustrating a bridge switching circuit constituted by multiple active switching devices.
Figure 1-2 is a schematic diagram of the invention illustrating the combination with a bridge rectifier to constitute a AC bi-directional active switching device.
Figure 2 is a circuit example of the invention.
DETAILED DESCRIPTION OF THE INVENTION The phase shift cut-off control circuit is an innovative circuit to provide effective phase angle conduction, whereby to further control the output voltage of the AC or intermittent pulse DC power source, thereof it is characterized in that the AC voltage at the first zeropassing value (or at the neighborhood) is the trigger point, and the second zero-passing value is the cut-off point, i. e. phase shift control is performed between the electrical angle 00-1800 to modulate the output voltage.
The power source voltage in the conventional phase control circuit is usually triggered between after the zero pulse value and before the next zero-passing value, and through the cut-off at the zero-passing value to control the voltage within the 00-1800 electrical angle in the conduction angle range, thereof its disadvantage is that the trigger action may evoke an instant rising surge current (especially at 90 angle) to generate electromagnetic noise and impact on the load.
Please refer to Enclosure 1 for the comparison of output wave shapes between the phase shift cut-off control circuit and the conventional phase shift conduction.
Figure 1 is the schematic block diagram of the phase shift cut-off control circuit illustrating the main circuit composition, which is mainly comprised of the following: A power source 100: It is a AC sinusoidal wave shape power source or a DC power source with zero-passing pulse wave shape or other zero-passing wave shape power source, or a DC power source with zero-passing intermittent pulse wave shape; A voltage zero-passing detector circuit 101: It is a circuit for detecting the voltage zero-passing, whereof it is constituted by solid state or electromechanical components, whereby to generate corresponding power signal when the power source voltage passing the zero value; Conduction timing control circuit 102:It is activated by the zero-passing detecting signal from the voltage zero-passing detector circuit to generate a conduction timing controllable driving signal which is automatically cut-off at the time when the corresponding phase angle is reached.
An active switching device 103: It is constituted by solid state or electromechanical switching components and its corresponding pre-driving circuit 104 to be directly driven by the conduction timing control circuit 102 to further control the loading power supply status of the power source to be triggered conduction by the zero-passing voltage, and is cut off before or at the second zero-passing voltage; thereof the active switching device 103 can be further provided with a bridge switching circuit constituted by multiple active switching devices to control the voltage polarities, or the said device can be combined with a bridge rectifier to constitute a AC bi directional active switching device to control the voltage.
A load 105: It is a rotational electrical machine or lighting device, or other resistive, inductive, or capacitive loads, or the mixture of the two or more than two of the above said loads; A compensation component 106: It is applicable for compensation in the case of load driven by DC pulse power source, whereof it includes adopting a reverse parallel combined flywheel diode as an inductive load compensation component, a parallel combined capacitor as a resistive load compensation component, whereas the series combined current-limited resistor may be used as a compensation component according to requirements for capacitive loads; therein the compensation components can be selectively installed according to requirements; A feedback circuit 107:It is a sensing component for detecting the physical status (including translation, velocity, direction, torque, temperature, brightness, sound intensity, etc.) or the chemical status of the load, whereby to feedback the power signal to control the conduction timing of the afore said conduction timing control circuit 102, thereof the feedback circuit can be selectively installed according to requirements; A signal source supply device 108: It is for supplying power required by the circuit components in the afore said various signal control circuits.
A signal input interface 109: It is constituted by electromechanical or solid state components, wherein it accepts the manual signal or power signal and provides input to the central controller to control the output status from the active switching device to the load, thereof the signal input interface can be selectively installed according to requirements.
A central controller 110: It is for controlling the phase shift cut-off control circuit to be driven in variable conduction angle or to be activated smoothly, or to accept the inputs from the feedback circuit and the control signal input interface for logic or program treating functions to control the conduction timing control circuit 102 and the active switching device; thereof it is constituted by a microprocessor and relevant softwares or other solid state or electromechanical circuit components, thereof the central controller can be selectively installed according to requirements.
Figure 2 is a circuit example of the phase shift cut-off control circuit, which is mainly comprised of the following: A power source 100: It is a AC sinusoidal wave shape power source or a DC power source with zero-passing pulse wave shape or other zero-passing wave shape power source, or a DC power source with zero-passing intermittent pulse wave shape; A voltage zero-passing detector circuit 101: It is constituted by operational amplifier and sampling circuit components, wherein it is by detecting the power source zero-passing point and the circuit for detecting the voltage zero-passing, whereof it is constituted by solid state or electromechanical components, whereby to generate corresponding power signal when the power source voltage passing the zero value; Conduction timing control circuit 102: It is constituted by a single steady state circuit, whereof it has a setting timing delay circuit to cut-off after activation by the zero-passing detecting signal from the voltage zero-passing detector circuit 101, whereby to generate a conduction timing controllable driving signal which is automatically cut-off when time is reached, thereof this circuit can be constituted by other timing circuits such as B555 series or by a microprocessor and relevant softwares; An active switching device 103:It is constituted by IGBT or other solid state switching transistors and pre-driving circuit 104 to be directly driven by the conduction timing control circuit 102 to further control the loading power supply status of the power source to be triggered conduction by the zero-passing voltage, and is cut off before or at the second zero passing voltage; thereof the active switching device 103 can be further provided with a bridge switching circuit constituted by multiple active switching devices to control the voltage polarities, or the said device can be combined with a bridge rectifier to constitute a AC bi-directional active switching device to control the voltage.
A signal source supply device 108: It is for supplying power required by the circuit components in the afore said various signal control circuits.
A signal input interface 109: It is constituted by adjustable resistors to control conduction time of the conduction timing control circuit 102, and to further control the working phase angle range for accepting the manual or power signal and providing inputs to the central controller to control the output status from the active switching device to the load.
Based on the above said principles, the phase shift cutoff control circuit can be further provided in multiple units and combining with multiple active switching device to constitute a multi-phase bridge circuit for applications in the phase shift cut-off control of the multi-phase AC power source to the load.
The voltage wave shape of the circuit can be improved according to the loading conditions through the following auxiliary components, whereof the compensation circuits includes the following: A resistive load parallel combined with an auxiliary capacitor, whereby the conducting current is always started to charge from zero, and the loading current to the resistor is smoothly increased, and at the time of cut-off, the compensation discharge current is provided to suppress the power noise from the sudden voltage drop;; An inductive DC motor load which smooth the voltage passing the front section of the sinusoidal wave of the power source when conducting and the motor armature EMF is extended backward to lower the voltage, thereby the electromagnetic noise is lower and the torque pulsation is smaller, and the circuit stability can be raised by parallel combining flywheel diodes at the two ends of the armature to absorb EMF as shown in Enclosure 2: A capacitive load to let the voltage always smoothly rise from the front section of the sinusoidal wave at conduction while the capacitor charging current smoothes input and at cut-off the capacitor discharge power to avoid the sudden voltage drop.
As is summarized from the above descriptions, the phase shift cut-off control circuit innovatively discloses an original technical idea of adopting zero-passing conduction and controlling the cut-off phase angle on the AC phase control circuits. As the industrial power equipments are getting more and more, the suppression of noise signal is becoming an important tendency, so the practical usefulness of the claim is obvious, and the applicant has survey the prior arts and found no similar disclosures, therefore, your legal approval on the claim is greatly appreciated.

Claims (4)

1. A phase shift cut-off control circuit which is an innovative circuit to provide effective phase angle conduction, whereby to further control the output voltage of the AC or intermittent pulse DC power source, thereof it is characterized in that the AC voltage at the first zero-passing value (or at the neighborhood) is the trigger point, and the second zero-passing value is the cut-off point, i. e. phase shift control is performed between the electrical angle 0 ~180 to modulate the output voltage, wherein it is mainly comprised of the following: A power source 100: It is a AC sinusoidal wave shape power source or a DC power source with zero-passing pulse wave shape or other zero-passing wave shape power source, or a DC power source with zero-passing intermittent pulse wave shape; A voltage zero-passing detector circuit 101:It is a circuit for detecting the voltage zero-passing, whereof it is constituted by solid state or electromechanical components, whereby to generate corresponding power signal when the power source voltage passing the zero value; Conduction timing control circuit 102: It is activated by the zero-passing detecting signal from the voltage zero-passing detector circuit to generate a conduction timing controllable driving signal which is automatically cut-off at the time when the corresponding phase angle is reached.
An active switching device 103: It is constituted by solid state or electromechanical switching components and its corresponding pre-driving circuit 104 to be directly driven by the conduction timing control circuit 102 to further control the loading power supply status of the power source to be triggered conduction by the zero-passing voltage, and is cut off before or at the second zero-passing voltage; thereof the active switching device 103 can be further provided with a bridge switching circuit constituted by multiple active switching devices to control the voltage polarities, or the said device can be combined with a bridge rectifier to constitute a AC bi-directional active switching device to control the voltage.
A load 105: It is a rotational electrical machine or lighting device, or other resistive, inductive, or capacitive loads, or the mixture of the two or more than two of the above said loads; A compensation component 106: It is applicable for compensation in the case of load driven by DC pulse power source, whereof it includes adopting a reverse parallel combined flywheel diode as an inductive load compensation component, a parallel combined capacitor as a resistive load compensation component, whereas the series combined current-limited resistor may be used as a compensation component according to requirements for capacitive loads; therein the compensation components can be selectively installed according to requirements; A feedback circuit 107:It is a sensing component for detecting the physical status (including translation, velocity, direction, torque, temperature, brightness, sound intensity, etc.) or the chemical status of the load, whereby to feedback the power signal to control the conduction timing of the afore said conduction timing control circuit 102, thereof the feedback circuit can be selectively installed according to requirements; A signal source supply device 108: It is for supplying power required by the circuit components in the afore said various signal control circuits.
A signal input interface 109: It is constituted by electromechanical or solid state components, wherein it accepts the manual signal or power signal and provides input to the central controller to control the output status from the active switching device to the load, thereof the signal input interface can be selectively installed according to requirements.
A central controller 110: It is for controlling the phase shift cut-off control circuit to be driven in variable conduction angle or to be activated smoothly, or to accept the inputs from the feedback circuit and the control signal input interface for logic or program treating functions to control the conduction timing control circuit 102 and the active switching device; thereof it is constituted by a microprocessor and relevant softwares or other solid state or electromechanical circuit components, thereof the central controller can be selectively installed according to requirements.
2. The phase shift cut-off control circuit as in claim 1, wherein it is comprised of the following: A power source 100: It is a AC sinusoidal wave shape power source or a DC power source with zero-passing pulse wave shape or other zero-passing wave shape power source, or a DC power source with zero-passing intermittent pulse wave shape; A voltage zero-passing detector circuit 101: It is constituted by operational amplifier and sampling circuit components, wherein it is by detecting the power source zero-passing point and the circuit for detecting the voltage zero-passing, whereof it is constituted by solid state or electromechanical components, whereby to generate corresponding power signal when the power source voltage passing the zero value; Conduction timing control circuit 102:It is constituted by a single steady state circuit, whereof it has a setting timing delay circuit to cut-off after activation by the zero-passing detecting signal from the voltage zero-passing detector circuit 101, whereby to generate a conduction timing controllable driving signal which is automatically cut-off when time is reached, thereof this circuit can be constituted by other timing circuits such as B555 series or by a microprocessor and relevant softwares; An active switching device 103:It is constituted by IGBT or other solid state switching transistors and pre-driving circuit 104 to be directly driven by the conduction timing control circuit 102 to further control the loading power supply status of the power source to be triggered conduction by the zero passing voltage, and is cut off before or at the second zero-passing voltage; thereof the active switching device 103 can be further provided with a bridge switching circuit constituted by multiple active switching devices to control the voltage polarities, or the said device can be combined with a bridge rectifier to constitute a AC bi-directional active switching device to control the voltage.
A signal source supply device 108: It is for supplying power required by the circuit components in the afore said various signal control circuits.
A signal input interface 109: It is constituted by adjustable resistors to control conduction time of the conduction timing control circuit 102, and to further control the working phase angle range for accepting the manual or power signal and providing inputs to the central controller to control the output status from the active switching device to the load.
3. The phase shift cut-off control circuit as in claim 1, wherein it can be further provided in multiple units and combining with multiple active switching device to constitute a multi-phase bridge circuit for applications in the phase shift cut-off control of the multi-phase AC power source to the load.
4. The phase shift cut-off control circuit as in claim 1, whereof the voltage wave shape of the circuit can be improvea according to the loading conditions through the following auxiliary components, whereof the compensation circuits includes the following: A resistive load parallel combined with an auxiliary capacitor, whereby the conducting current is always started to charge from zero, and the loading current to the resistor is smoothly increased, and at the time of cut-off, the compensation discharge current is provided to suppress the power noise from the sudden voltage drop; ; An inductive DC motor load which smooth the voltage passing the front section of the sinusoidal wave of the power source when conducting and the motor armature EMF is extended backward to lower the voltage, thereby the electromagnetic noise is lower and the torque pulsation is smaller, and the circuit stability can be raised by parallel combining flywheel diodes at the two ends of the armature to absorb EMF.
A capacitive load to let the voltage always smoothly rise from the front section of the sinusoidal wave at conduction while the capacitor charging current smoothes input and at cut-off the capacitor discharge power to avoid the sudden voltage drop.
GB9511076A 1995-06-01 1995-06-01 Phase angle control circuit for a switching device Withdrawn GB2301716A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB9511076A GB2301716A (en) 1995-06-01 1995-06-01 Phase angle control circuit for a switching device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB9511076A GB2301716A (en) 1995-06-01 1995-06-01 Phase angle control circuit for a switching device

Publications (2)

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GB9511076D0 GB9511076D0 (en) 1995-07-26
GB2301716A true GB2301716A (en) 1996-12-11

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GB9511076A Withdrawn GB2301716A (en) 1995-06-01 1995-06-01 Phase angle control circuit for a switching device

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2770943A1 (en) * 1997-11-13 1999-05-14 Francois Kneider Controlling electricity supply to load
GB2332108A (en) * 1997-12-05 1999-06-09 Samsung Kwang-Ju Electronics Co Ltd Motor phase control apparatus

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1389261A (en) * 1972-03-21 1975-04-03 Litton Industrial Products Method and means for controlling the output conditions of a self-excited alternating current motor
GB1463010A (en) * 1974-06-21 1977-02-02 Cohen A A Digital speed control system for an electric motor
GB2011195A (en) * 1977-10-11 1979-07-04 Midland Binding Machines Ltd Controlling the supply of a.c. to a load
EP0247650A2 (en) * 1986-04-30 1987-12-02 Philips Electronics Uk Limited Motor speed control system
GB2212013A (en) * 1985-05-03 1989-07-12 Hoover Plc Electric motor controller
US4996469A (en) * 1990-03-16 1991-02-26 Allen-Bradley Company, Inc. Electric motor controller with bypass contactor
US5008608A (en) * 1989-12-26 1991-04-16 Allen-Bradley Company, Inc. Controller for starting and stopping electric motors

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1389261A (en) * 1972-03-21 1975-04-03 Litton Industrial Products Method and means for controlling the output conditions of a self-excited alternating current motor
GB1463010A (en) * 1974-06-21 1977-02-02 Cohen A A Digital speed control system for an electric motor
GB2011195A (en) * 1977-10-11 1979-07-04 Midland Binding Machines Ltd Controlling the supply of a.c. to a load
GB2212013A (en) * 1985-05-03 1989-07-12 Hoover Plc Electric motor controller
EP0247650A2 (en) * 1986-04-30 1987-12-02 Philips Electronics Uk Limited Motor speed control system
US5008608A (en) * 1989-12-26 1991-04-16 Allen-Bradley Company, Inc. Controller for starting and stopping electric motors
US4996469A (en) * 1990-03-16 1991-02-26 Allen-Bradley Company, Inc. Electric motor controller with bypass contactor

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2770943A1 (en) * 1997-11-13 1999-05-14 Francois Kneider Controlling electricity supply to load
GB2332108A (en) * 1997-12-05 1999-06-09 Samsung Kwang-Ju Electronics Co Ltd Motor phase control apparatus
GB2332108B (en) * 1997-12-05 2000-02-02 Kwangju Electronics Co Limited Motor phase control apparatus

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Publication number Publication date
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