Abstract: A method is for controlling a three-phase current converter. First, subtract a second reference current signal representing the predicted current of the three-phase terminals in the present switching cycle from a first reference current signal representing the predicted current of the three-phase terminals in the next switching cycle to obtain a predicted variation. Then, subtract a feedback current signal representing the feedback current of the three-phase terminals in the previous switching cycle from the second reference current signal delayed by one switching cycle to obtain a current error. Multiply the current error by an error coefficient then add the predicted variation to obtain a current variation. Finally, obtain duty ratios of a plurality of switches, according to the current variation and inductance of the first to the third inductor. The three-phase current converter converts electric power between a DC terminal and the three-phase terminals, according to the duty ratio.

Abstract: A method is for controlling a three-phase current converter. First, subtract a second reference current signal representing the predicted current of the three-phase terminals in the present switching cycle from a first reference current signal representing the predicted current of the three-phase terminals in the next switching cycle to obtain a predicted variation. Then, subtract a feedback current signal representing the feedback current of the three-phase terminals in the previous switching cycle from the second reference current signal delayed by one switching cycle to obtain a current error. Multiply the current error by an error coefficient then add the predicted variation to obtain a current variation. Finally, obtain duty ratios of a plurality of switches, according to the current variation and inductance of the first to the third inductor. The three-phase current converter converts electric power between a DC terminal and the three-phase terminals, according to the duty ratio.

Abstract: A control circuit of a driving circuit for controlling a light emitting diode (LED) light source having a plurality of areas is provided. The control circuit includes the error amplifiers receiving a feed back current signal and a external reference voltage, and generating an error signal; a buffer register receiving a serial digital signal and generating the parallel digital signals; a work register receiving the parallel digital signals and a trigger signal, and outputting the parallel digital signals when the trigger signal is at a relatively high level; and a switch module having the power switches, each of which receives the error signal and the parallel digital signal for generating a driving signal to control a driving current of a specific area of the light source, in order to control the brightness in each area of the LED light source.

Abstract: A solar generator capable of power tracking and electric characteristic curve measurement and a method for realizing the same is disclosed. The solar generator of the present invention comprises at least one solar panel receiving solar energy, converting the solar energy into electric energy, and outputting the electric energy; an electric tracking-measuring circuit connected with the solar panel and the external load; and a processor connected with the electric tracking-measuring circuit, controlling the electric tracking-measuring circuit to receive the electric energy and output the electric energy to the external load at the highest power. When the illumination on the solar panel is greater than a preset value, the processor controls the electric tracking-measuring circuit to measure the I-V characteristic curve of the electric energy to determine the operation status of the solar panel.

Abstract: A control circuit of a driving circuit for controlling a light emitting diode (LED) light source having a plurality of areas is provided. The control circuit includes the error amplifiers receiving a feed back current signal and a external reference voltage, and generating an error signal; a buffer register receiving a serial digital signal and generating the parallel digital signals; a work register receiving the parallel digital signals and a trigger signal, and outputting the parallel digital signals when the trigger signal is at a relatively high level; and a switch module having the power switches, each of which receives the error signal and the parallel digital signal for generating a driving signal to control a driving current of a specific area of the light source, in order to control the brightness in each area of the LED light source.

Abstract: A ripple-free drive circuit for LED backlights of an LCD panel includes a PFC circuit, a DC/DC converter, three output load units, and a drive voltage resetter. The PFC circuit is connected with the mains power for outputting DC power. The DC/DC converter is connected with the PFC circuit. The three output load units are connected with the DC/DC converter for outputting red, green, and blue lights respectively, each having an electrically-controlled switch. The drive voltage resetter is connected with the DC/DC converter and the three output load units for preventing the three output load units from generation of surge current in a moment of electric conduction. In light of this, the ripple-free drive circuit is qualified as the drive power source of the LED backlights and can effectively isolate the surge current to prevent the surge current from entry into the output load units.

Abstract: A power factor correction controller simultaneously controls several power converters to be operated at a critical conduction mode to improve the overall conversion efficiency and conversion power of the power factor corrector. The controller includes a primary power converter control circuit for feeding back an input voltage signal, an output voltage signal and a primary current signal, and outputting a primary gate control signal for controlling a primary power switch; at least one secondary power converter control circuit for receiving the primary gate control signal and outputting a secondary gate control signal for controlling a secondary power switch; and a phase splitter circuit for receiving the primary gate control signal to control a gate output driving circuit, so that the gate output driving circuit outputs the secondary gate control signal.

Abstract: A power factor correction controller simultaneously controls several power converters to be operated at a critical conduction mode to improve the overall conversion efficiency and conversion power of the power factor corrector. The controller includes a primary power converter control circuit for feeding back an input voltage signal, an output voltage signal and a primary current signal, and outputting a primary gate control signal for controlling a primary power switch; at least one secondary power converter control circuit for receiving the primary gate control signal and outputting a secondary gate control signal for controlling a secondary power switch; and a phase splitter circuit for receiving the primary gate control signal to control a gate output driving circuit, so that the gate output driving circuit outputs the secondary gate control signal.

Abstract: A multi-lamp driving system for driving lamp units includes a multi-phase alternating current (AC) power generating unit for generating a plurality of out-of-phase AC current signals, and a balancing unit for balancing current flowing through each lamp unit. The balancing unit includes a plurality of loads, and a multi-phase transformer that has a plurality of coils. Each lamp unit is adapted to be connected to at least one of a respective load and a respective coil, and forms a series connection with the respective load and the respective coil. The series connection of each lamp unit with the respective load and the respective coil is coupled across the AC power generating unit.

Abstract: A motor variator and a driving method thereof are provided for controlling the operating speed of a fan, which employ an alternate current chopper to change the working cycle and the rotary speed of a stepless motor. The motor variator includes a high-frequency alternate current chopper connected to an induction coil of an induction motor, an alternate current power supply connected to the high-frequency alternate current chopper and a controller connected to the high-frequency alternate current chopper for outputting a switch signal to the high-frequency alternate current chopper, such that the high-frequency alternate current chopper is controlled by the switch signal to perform a chopper action for the alternate current power supply and output a drive voltage, so as to change the rotary speed of the induction motor.

Abstract: A self-sourcing exercise bike with a linear digital control magnetic resistance braking apparatus comprises a generator, a power converter, a digital control system, a magnetic braking resistance and a LED control panel. This apparatus uses a linear control method to control the change of the magnetic resistance, and the magnetic resistance braking apparatus uses a method of changing inductance and a controlling way thereof to achieve the goal of controlling the variation of the magnetic resistance braking force. This bike makes the user or rehabilitant to linearly adjust the resistance force or torque according to the speed of the exercise bike and the presetting resistance force, and easily start up the power system in the initial stage.

Abstract: A power factor corrector control device accomplishes control of power factor correction with a simpler and cheaper circuit, overcomes the drawback of higher current harmonics occurred in the prior art, and also accommodates mains voltage distortion. This power factor corrector control device uses a built-in circuit to discriminate the mains frequency, and generates a pure sinusoidal signal having the same frequency with the mains frequency. The product of a feed-forward signal and an output error signal is exploited to get a constant by using a sample-and-hold circuit to determine the amplitude of a reference current signal, hence preventing ripples of the feed-forward signal and the output error signal from generating distortion of the reference current signal after circuit operation. Moreover, a division approximate circuit is used to accomplish simple feed-forward control so as to apply to various different mains voltage levels.

Abstract: A multi-lamp driving system for driving lamp units includes a multi-phase alternating current (AC) power generating unit for generating a plurality of out-of-phase AC current signals, and a balancing unit for balancing current flowing through each lamp unit. The balancing unit includes a plurality of loads, and a multi-phase transformer that has a plurality of coils. Each lamp unit is adapted to be connected to at least one of a respective load and a respective coil, and forms a series connection with the respective load and the respective coil. The series connection of each lamp unit with the respective load and the respective coil is coupled across the AC power generating unit.

Abstract: An electric energy auxiliary device of transdermal drug delivery patch is provided which includes an upper electrode, a lower electrode, and a drug storage area between two electrodes, generating a kinetic energy in the pharmaceutical compound in the drug storage area toward the skin by a electric field between two electrodes. For the pharmaceutical compound with the same polarity, the pharmaceutical compound is pushed by the electric energy interacted with polar the pharmaceutical compound so as to deliver the drug the human body. The lower electrode generates an ion channel with electroporation on the surface of skin. By using the change of electric field on the surface of skin, a temporary ion channel is generated in the cells where the pharmaceutical compound enters the systemic circulation of human body via skin. This temporary ion channel allows large compound to pass into the skin of human body.

Abstract: A speed adjuster is provided in a belt-disc sander for controlling the rotating speed of a motor of the belt-disc sander. A speed adjust knob is disposed outside the belt-disc sander. The speed adjuster has a control circuit, a current sensor, a drive circuit, and a converter. The current sensor detects the motor current and feeds back to the control circuit, which controls the frequency variation of a SPWM signal of the drive circuit in response to the input of the speed adjust knob. The converter transforms the square wave voltage into an AC voltage for driving the motor. The desired rotating speed can be adjusted through the speed adjust knob. The control circuit will compare the present rotating speed of the motor with the set rotating speed to determine whether the present rotating speed conforms to the set one for correcting the rotating speed of the motor.

Abstract: An electronic ballast system with emergency lighting features is presented. Especially, the electronic ballast system is relative to a single-stage converter configuration. The electronic ballast system serves as a regular ballast, a regular/emergency ballast, a battery charger or discharger and a power failure detector, fulfilling emergency lighting features. The single-stage converter used in the ballast is an integration of a bi-directional flyback converter and two half-bridge series-resonant parallel-loaded inverters. Unlike conventional approaches, the rectified and filtered input voltage is directly added to a set of battery voltages in the proposed system, so as to reduce the fabrication cost by simplifying the circuit configuration and the number of active switching elements.

Abstract: A compact single-stage electronic ballast circuit for emergency lighting applications, integrating the functions of a flyback charger, a flyback discharger and a half-bridge series resonant parallel loaded electronic ballast into a single-stage electronic ballast. The present invention only employs two active switches so as to achieve an electronic ballast for emergency lighting applications when the electricity is out. Furthermore, the present invention reduces the fabrication cost by simplifying the circuit configuration and reducing the number of employed active switching elements.

Abstract: A compact single-stage electronic ballast circuit for emergency lighting applications, integrating the functions of a flyback charger, a flyback discharger and a half-bridge series resonant parallel loaded electronic ballast into a single-stage electronic ballast. The present invention only employs two active switches so as to achieve an electronic ballast for emergency lighting applications when the electricity is out. Furthermore, the present invention reduces the fabrication cost by simplifying the circuit configuration and reducing the number of employed active switching elements.

Abstract: A preheating circuit for a fluorescent lamp is provided. The preheating circuit includes a filament detecting circuit indirectly detecting a filament resistance in a fluorescent lamp by measuring a filament voltage and a filament current, a pulse generation circuit providing pulses of one of a first frequency and a second frequency determined by the detected filament resistance and a specific filament resistance, and a filament resonance circuit operating the fluorescent lamp at an operating frequency determined by the pulse generation circuit. Therefore, the filament resonance circuit operates at the first frequency to preheat the fluorescent lamp when the detected filament resistance is smaller than the specific resistance. The filament resonance circuit operates at the second frequency to operate the fluorescent lamp when the detected filament resistance is one of a first value being larger than and a second value being equal to that of the specific resistance.