Abstract: A controller for use in a power supply regulator is disclosed. One controller includes a feedback circuit coupled to generate an equivalent switching frequency signal in response to a sense signal from a power supply regulator output. A comparator is coupled to compare the equivalent switching frequency signal with a reference signal. A period modulation circuit is coupled to the feedback circuit to generate a period modulation switching signal in response to the equivalent switching frequency signal. A multi-cycle modulator circuit is coupled to the output of the comparator. The multi-cycle modulator circuit is coupled to enable or disable a switch signal from the controller, which is to be coupled to a switch of the power supply regulator. A group of two or more consecutive switching cycles is separated from a next group having two or more switching cycles by a time of no switching.

Abstract: A method for an inverter, for inputting power output by a direct current voltage source in an alternating current voltage network chops the direct current voltage source by a bridge inverter by alternate switching of parallel-mounted and series-mounted circuit elements, in the form of a pulse width modulation, and the chopped power is transmitted via a transformer which is connected between the series-mounted elements. The transmitted power is then rectified and input in the alternating current voltage network via a down-converter transformer. In order to adapt the inverter to the power supplied, the switching times of the circuit elements of the bridge inverter are controlled or regulated.

Abstract: A power conversion apparatus for converting direct current from a power source to polyphase alternating current includes a plurality of carrier signal generators, a plurality of gate signal generators, and a plurality of legs. The carrier signal generators are configured and arranged to independently generate and transmit a plurality of carrier signals, respectively. The gate signal generators are operatively coupled to the carrier signal generators, respectively, to receive the carrier signals, each of the gate signal generators being configured and arranged to generate an on/off signal by comparing a command value of each phase of the polyphase alternating current and corresponding one of the carrier signals. The legs are connected to the gate signal generators. Each of the legs is operated based on the on/off signal transmitted from corresponding one of the gate signal generators to convert the direct current to each phase of the polyphase alternating current.

Abstract: A sampling method with adjusting duty ratios is provided and includes the following steps. A first working pulse signal which has a pulse-width duty ratio D in a switching period Ts is provided. A first adjusting period comprising first N successive switching periods of the first working pulse signal is set, wherein N is a natural number larger than 1. A second working pulse signal which has second N successive switching periods with their corresponding pulse-width duty ratio D1, D2, . . . , DN to drive the switch in the converter circuit is provided and the measured signal is generated, wherein the sum of D1, D2, . . . , DN substantially equals to N·D and the second N successive switching periods constitute a second adjusting period.

Abstract: A method of controlling a power converter is used to interface to a power grid or supply network operating at a frequency (Fnet) that is nominally fixed (say at 50 Hz, for example) but which can be varied as a way of controlling power imbalanced within the network as a whole. The power converter can include a network bridge that operates in accordance with the pulse width modulation (PWM) strategy having a switching frequency (Fpwm), a nominal switching frequency (Fpwm_nom) and a number of pulses per period (Pulse_Number).

Abstract: A DC/DC converter includes a reactor, IGBT devices, a dead time generation unit, and a DC-CPU. The dead time generation unit operates in response to a reference signal for a duty ratio, to output first and second activation signals provided with an inactive period corresponding to a dead time preventing both of the IGBT devices from conducting. The DC-CPU corrects a tentative duty ratio calculated as based on a voltage control value, in accordance with a value of a current flowing through the reactor, to output the reference signal. Preferably the DC-CPU associates the value of the current of the reactor with three states and when the value approaches a value at which a state transitions to a different state, the DC-CPU gradually switches a correction value.

Abstract: A low-power digital pulse-width modulator (DPWM) architecture for high frequency dc-dc switch-mode power supplies (SMPS) is disclosed that is well-suited for integration in power management systems of small handheld devices. The DPWM can operate in a stand-alone mode, without external clock, and can be implemented on a portion of silicon area needed for other DPWM solutions. In addition it has low power consumption and provides a good linearity of the input-to-output characteristic, also not characteristic for other architectures.

Abstract: A switching mode power supply includes: a power supply unit that comprises a switch that is coupled to a primary coil at a primary side of a transformer for converting an input DC voltage, and that supplies power to a secondary coil and a tertiary coil at a secondary side of the transformer according to an operation of the switch; a switching controller that receives a feedback voltage corresponding to a first voltage generated in the secondary coil at the secondary side of the transformer, and receives a detection signal corresponding to a current flowing to the switch to control an on/off operation of the switch; and a feedback signal generator that receives the first voltage and the switching control signal, samples the first voltage by using first pulse strings, and generates the feedback voltage according to a level of the first voltage sampled by a first pulse in the first pulse strings, wherein a toggling time of the first pulse strings is changed in a first period for sampling the first voltage, and a

Abstract: A first inverter control unit includes a harmonic generation unit. The harmonic generation unit generates a harmonic voltage instruction having a phase opposite to a harmonic generated at a neutral point of a motor-generator when the motor-generator revolves, based on motor revolution number of the motor-generator. A PWM signal generation unit generates a signal based on a voltage instruction obtained by superimposing an AC voltage instruction from an AC output control unit and the harmonic voltage instruction from the harmonic generation unit onto each voltage instruction of U-phase, V-phase and W-phase from a conversion unit.

Abstract: Systems and methods are provided for operating a pulse width modulation (PWM) circuit in a direct current (DC) to alternating current (AC) power inverter to reduce the magnitude of harmonics. The PWM circuit operates using a reference signal having an irregular period. In one implementation the irregular periodicity includes a sequence of periods uniformly distributed about a target period.

Abstract: A switching mode power supply (SMPS) and a driving method thereof are provided. The SMPS includes a power supply block that includes a first switch coupled to a first coil of a primary side of a transformer for converting an input voltage, wherein the power supply block supplies power to a second coil and a third coil of a secondary side of the transformer according to operation of the first switch; and a PWM signal generator determines a turn-on time of the first switch according to the input voltage, and the turn-on time is determined regardless of a power magnitude of an output terminal connected to the second coil. Accordingly, screen noise due to a ripple can be eliminated and stress on the switch breakdown due to excessive power input can be reduced to enable an SMPS with stable driving.

Abstract: A power source module is assembled on a main printed circuit board. The power source module comprises an input processing circuit, a PFC/PWM control circuit, a conversion circuit, and an output processing circuit. The input processing circuit is for rectifying an alternating current voltage to be a primary direct current voltage. The PFC/PWM control circuit is for modulating the primary direct current voltage. The PFC/PWM control circuit is assembled on a subsidiary printed circuit board electrically connected to the main printed circuit board. The conversion circuit is for converting the primary direct current voltage to be a secondary direct current voltage. The output processing circuit is for rectifying and filtering the secondary direct current voltage.

Abstract: Converter and method for controlling a converter with power semiconductor switches, having a filter (1) which is connected to the power semiconductor switches and having a drive circuit (4) which is connected to the power semiconductor switches for the purpose of modulation, wherein, as a result of the modulation, a fundamental at a fundamental frequency (fGS) is generated in a passband (P) of the filter (1), modulation products are generated in a first frequency band (FB1), in a second frequency band (FB2) and in an intermediate frequency band (ZFB) which is formed between the first frequency band (FB1) and the second frequency band (FB2), the modulation products in the intermediate frequency band (ZFB) are reduced in comparison with the modulation products in the first frequency band (FB1) and the modulation products in the second frequency band (FB2),; and the intermediate frequency band (ZFB) is generated, in a resonant range (R) of a resonant frequency (fres) of the filter (1), between the passband (P) a

Abstract: A control device calculates a voltage command value of a voltage step-up converter based on a torque command value and a motor revolution number and calculates the on-duty of an NPN transistor based on the calculated voltage command value and a DC voltage from a voltage sensor. Under the conditions that the on-duty is influenced by a dead time and the DC voltage is smaller than a predetermined set value, the control device controls NPN transistors to step-up or step-down the voltage while fixing the on-duty at 1.0.

Abstract: Audible noise in resonant switching power converter during low-power burst mode operation is reduced by spreading the spectrum generated by the bursts, thereby reducing the amplitude of audio spectrum peaks in the current supplied through the resonant tank from a switching circuit. The spreading can be accomplished by varying the intervals between the bursts and/or by varying a pulse pattern within the bursts. The pulse pattern within the bursts can be varied by varying the number of pulses in the bursts, the polarity of the initial pulse of the bursts, and/or the duration of pulses within the bursts either uniformly or randomly. The burst pulse pattern may also be selected in alternation from a set of pulse patterns stored in a memory and the selection may be made randomly or systematically.

Abstract: A method and apparatus for reducing common mode noise in a three phase pulse width modulated (PWM) system, the method comprising the steps of receiving the first, second and third modulating waveforms, identifying one of the modulating waveforms that is at least one of instantaneously the maximum and instantaneously the minimum of the modulating waveforms as a first identified waveform, wherein comparison of the first identified waveform to the carrier signal would generate a first on-off pulse sequence associated with a phase corresponding to the first identified waveform, generating switch control signals associated with the phase corresponding to the first identified waveform that cause a modified on-off pulse sequence that is phase shifted from the first pulse sequence, using the second and third modulating waveforms to generate second and third on-off pulse sequences corresponding to the second and third phases and providing the modified pulse sequence and the second and third pulse sequences to the one

Abstract: The resistors of a filter block in a voltage source converter station are connected with a floating neutral point.

Abstract: A night vision system comprising a power system having a low voltage unit coupled to a high voltage unit; the low voltage unit including a low voltage controller generating a pulse width code; the high voltage unit including an opto-isolator for receiving the pulse width code from the low voltage controller, a high voltage controller operative in response to the pulse width code to generate an output pulse, a pulse shaping module receiving the output pulse and generating a control pulse; and power electronics operative in response to the control pulse.

Abstract: A PWM generator system provides improved duty cycle resolution using a sub-cycle generator for generating a sub-cycle with a period that is a small fraction of the maximum PWM period to be generated. An integral sub-cycle estimator is coupled to said sub-cycle generator for determining the integral number of said sub-cycles for on and off time of the PWM waveform. An additional sub-cycle estimator determines the additional fractional sub-cycle required to provide the on and off time. A timer coupled to the integral sub cycle estimator and the additional sub cycle estimator controls PWM output switching for the on and off time of the integral and additional fractional sub cycles.

Abstract: A control device for a power converting device which performs PWM on an output from a DC power supply and produces an output of AC power, including: a current controller which converts a given current command value into a voltage command value; a carrier generator which generates a PWM carrier; a PWM generator which generates a PWM signal to be fed to the power converting device according to the voltage command value and the PWM carrier; a frequency controller which effects a change in the frequency of the PWM carrier from the carrier generator; and a current control gain controller which effects a change in the current control gain of the current controller according to the change in the frequency of the PWM carrier. The current control gain of the current controller is changed according to the change in the frequency of the PWM carrier from the carrier generator.

Abstract: An inverter includes a counter, a PWM generator, a central controller and a power converter. The counter is used for receiving a frame switch signal to generate a frame counting signal. The PWM generator is coupled to the counter, and is used to select a specific frequency among a plurality of predetermined frequencies according to the frame counting signal, and generate a modulated signal having the specific frequency. The central controller is coupled to the PWM generator, and is used to generate a processed signal according to the modulated signal. The power converter is coupled to the central controller, and is used to generate an output signal according to the processed signal.

Abstract: A power generation system for supplying a resultant output voltage is provided. The system comprises a power converter system. The power converter system comprises at least two power converter bridges, each configured for switching at a low frequency and generating a corresponding converter output voltage including a fundamental voltage component and harmonic components, and at least two power converter transformers. Each power converter bridge is coupled to a primary winding of a corresponding power converter transformer and a secondary winding of one power converter transformer is coupled to a secondary winding of a second power converter transformer. The resultant output voltage comprises a sum of the fundamental voltage components of each converter output voltage.

Abstract: Disclosed is a current mode switched power supply. The current mode switched power supply includes a switching element and a power stage coupled to the switching element and configured to provide, in response to the switching of the switching element, an output voltage and a feedback voltage related to the output voltage. The current mode switched power supply also includes a digital control circuit connected to the switching element to digitally control the switching of the switching element.

Abstract: An apparatus and method for controlling an inverter, the apparatus including an adjustable frequency controller receiving a reference frequency value and generating a command frequency value as a function thereof, an adjustable voltage controller receiving a reference voltage value and generating a command voltage value as a function thereof and independent of the command frequency and a modulator receiving the command frequency value and the command voltage value and generating pulse width modulated (PWM) inverter control signals as a function thereof.

Abstract: Preferred embodiments of the present invention provide systems and methods that automatically correct the desired on-time of switching elements as the resonant frequency changes, so as to maintain the correct proportional value.

Abstract: A reverse current detection unit detects the direction of the motor current during the synchronous rectifier period based on the polarity of the on voltage of a switching device contained in the motor current path, and outputs a reverse current detection signal representing the result of this detection to the PWM control unit. Change in the output of the PWM control unit that generates the drive signal for a particular switching device in the drive unit is controlled based on the reverse current detection signal and the energizing pattern of the drive unit is changed when motor current is detected in the synchronous rectifier period to be flowing in the opposite direction as in the urging period. The flow of motor current to the power supply is thus reduced and a rise in the power supply voltage can be prevented.

Abstract: A method for controlling a three-level inverter with a two-level inverter controller uses a conversion circuit to process the two-level control signals and output a set of three-level control signals.

Abstract: A primary side controlled power converter having a voltage sensing means coupled to a transformer of the power converter and configured to provide a voltage feedback waveform representative of an output of the transformer is provided. A primary switching circuit operates to control energy storage of a primary side of the transformer. The primary switching circuit is operable during an on time and inoperable during an off time. The on and off time is switched at a system frequency. A feedback amplifier generates an error signal indicative of a difference between the voltage feedback waveform and a reference voltage. A sample and hold circuit samples the error signal at a periodic frequency during the off time. An error signal amplifier is configured to provide the sampled value to the primary switching circuit wherein the primary switching circuit controls the transformer and thereby regulates an output of the power converter.

Abstract: An inverter receives a DC power supply and converts it into AC power to a primary coil of a high frequency transformer. The output of the high frequency transformer passes through two secondary coils, and each secondary coil is associated with a bus. The busses supply positive and negative AC power to a downstream output. The flow of the power from the two busses is alternatively controlled to provide a desired frequency on the output.

Abstract: A discharge lamp lighting apparatus includes a triangular signal oscillator, a first control part to compare the triangular signal with an error voltage between a reference voltage and a voltage corresponding to a first current passed through a secondary winding of a transformer and generate a first PWM control signal for turning on/off switching elements Qp1 and Qn1 with a phase difference of about 180 degrees and a pulse width corresponding to the first current, and a second control part to compare the triangular signal with an error voltage between a reference voltage and a voltage corresponding to a second current passed through a secondary winding S2 of a transformer T2 and turn on/off switching elements Qp2 and Qn2 in synchronization with the first PWM control signal with a phase difference of about 180 degrees and a pulse width corresponding to the second current.

Abstract: A PWM signal generating circuit that generates a PWM signal having a period controlling portion for slightly fluctuating a period of the PWM signal; and a duty controlling portion for changing a duty of the PWM signal by changing a duty ratio in the period fluctuated by the period controlling portion.

Abstract: The present invention pertains to a switching regulator having two inductors that discharge stored energy during the switching operation to an output capacitor, which integrates the pulses and supplies an average voltage plus ripple to a load. The two inductors are each connected to one of a pair of equivalent inductors to form a common mode filter having magnetically interacting windings that introduce negligible inductance in series with a differential mode of current flow, in which the current in the winding of one of the pair of inductors opposes the current in the winding of the other pair of inductors during exposure to a common mode signal resulting in a cancellation of ripple current flow reaching the load.

Abstract: A pulse width modulation (PWM) generator featuring very high speed and high resolution capability and the ability to generate standard complementary PWM, push-pull PWM, variable offset PWM, multiphase PWM, current limit PWM, current reset PWM, and independent time base PWM while further providing automatic triggering for an analog-to-digital conversion (ADC) module that is precisely timed relative to the PWM signals. Applications include control of a switching power supply that requires very high speed operation to obtain high resolution at high switching frequencies, and the ability to vary the phase relationships among the PWM output signals driving the power supply power components. A single PWM duty cycle register may be used for updating any and/or all PWM generators at once to reduce the workload of a digital processor as compared to updating multiple duty cycle registers.

Abstract: A method for starting the modulation of a frequency converter, which method comprises the steps of receiving reference voltages (sa, sb, sc; Uref), generating output switch commands from the reference voltages. The generation of output switch commands comprises further a step, in which the ratio (dz) of active time (T0+) in a modulation period (Ts) of selected zero vector and the total active time (T0++T0?) of zero vectors in a modulation period is changed from a first predetermined ratio, which is substantially 0 or 1, to a second predetermined ratio, which is substantially 0.5.

Abstract: Mitigating the DC content of an AC output from an inverter is important for electrical system reliability. The inverter may be powered by unbalanced DC inputs while still mitigating the DC content of the AC output wavefrom. The present invention provides methods to mitigate the DC content in the output DC voltage by reshaping the PWM reference signals (carrier signals) according to the DC content in such a way that the DC content is canceled. These reshaped PWM reference signals may be, for example, unsymmetrical reference waveforms. Unlike conventional methods for providing an AC voltage from a DC voltage with an inverter, which may result in DC content in the output AC voltage when an unbalanced DC input voltage is supplied, the present invention provides methods for mitigating the DC content in an AC voltage, even if the inverter providing the AC voltage is supplied with unbalanced DC voltage.

Abstract: A power converting apparatus used as an active filter includes single-phase multiplex inverter unit for converting DC power into AC power and a control unit for controlling the single-phase multiplex inverter unit. The single-phase multiplex inverter unit includes a first single-phase inverter and a second single-phase inverter. The first single-phase inverter to which a maximum DC voltage is supplied outputs voltage pulses at a rate of one pulse per half the period of an AC voltage fed from an AC source. The control unit includes a pair of hysteresis comparator circuits for driving the second single-phase inverter such that an AC source current follows a sinusoidal target current.

Abstract: Systems and methods are provided for distributing power to a load by controlling an uninterruptible power supply that has an inverter and a filter, where the filter has an inductor and a capacitor. The systems and methods apply a pulse width modulation control signal to the inverter, sample inverter inductor current and compare the inductor current to a reference current. A duty cycle of the pulse width modulation control signal is adjusted to drive the inductor current at a second sampling time to a value substantially equal to a reference current at a first sampling time. The systems and methods can filter harmonic distortion from output signals and control uninterruptible power supply output.

Abstract: This invention relates to SMPS controllers employing primary side sensing. We describe a system for identifying a knee point in a sensing waveform, at which the output voltage of the SMPS may be sampled accurately on the primary side. The system identifies the knee point by fitting a tangent to a portion of a power transformer voltage waveform, and samples the voltage waveform at the knee point to determine the SMPS output voltage. In preferred embodiments this technique is implemented using a decaying peak detector, providing a timing signal indicating detection of the knee point. Sample/hold and error amplifier circuits may be employed to achieve output voltage regulation.

Abstract: In a voltage regulator including an error amplifier to generate a first signal related to an output voltage of the voltage regulator, a current sense circuit to generate a second signal related to an inductor current of the voltage regulator, and a PWM comparator to generate a PWM signal in response to the first and second signals to regulate the output voltage, a current feed-through adaptive voltage position control comprises supplying ramp signal and offset signal to modify the PWM signal to thereby eliminate the offset of the output voltage.

Abstract: In a power converter apparatus, such as an uninterruptible power supply, a phase reference signal is generated responsive to a DC voltage on a DC bus. A magnitude reference signal may be generated responsive to a phase current of an AC bus and/or the DC voltage on the DC bus. Power is transferred between the AC and DC busses responsive to the phase reference signal and the magnitude reference signal. Generation of the phase reference signal may include generating a DC voltage error signal responsive to the DC voltage on the DC bus, generating a phase offset signal responsive to the DC voltage error signal, and generating the phase reference signal responsive to the phase offset signal. Generation of the magnitude reference signal may include generating a volt-amperes reactive (VAR) error signal responsive to the phase current and generating the magnitude reference signal responsive to the VAR error signal.

Abstract: A power supply device comprises: a voltage converting portion that converts a voltage generated from a power supply portion into an output voltage to be supplied to a load; a voltage divider circuit that generates an output voltage setting signal for providing a set value of the output voltage; a set value changeover portion that turns on/off set value changeover switches to change a voltage divider ratio of the voltage divider circuit to change the set value; a storage device that stores a state appropriate for each set value changeover switch for keeping the value of the output voltage within a specified range; a set value changeover switch control portion that controls the set value changeover switches so as to bring each set value changeover switch into a state as stored in the storage device when the voltage is supplied from the voltage converting portion to the load; and an output voltage control portion that controls the voltage converting portion so as to make zero a deviation between the value of the

Abstract: Measured or otherwise known operating characteristics of a DC/DC power converter are used to determine, without measuring, an operating characteristic of the DC/DC power converter.

Abstract: There is provided a PWM inverter capable of preventing a phase error from occurring in generating a PWM signal even in the case where a carrier wave frequency is not sufficiently higher than a signal wave frequency. A PWM signal generating section (2) includes a phase adjusting section (11) configured to advance a phase of the signal wave by adding, to a signal wave, a delay component of the PWM signal with respect to the signal wave, the phase delay component being involved by digital control. Furthermore, in a case where the carrier wave frequency is changed, the phase delay component with respect to the signal wave is updated in synchronism with the timing of change of the carrier wave frequency.

Abstract: This invention relates to switch mode power supply (SMPS) controllers employing primary side sensing. We describe an (SMPS) controller which uses an area correlator to compare an area under a feedback signal waveform between a start point defined by said first timing signal and an end point defined by said second timing signal with a reference area. An output of the area correlator provides an error signal for regulating the SMPS output.

Abstract: A motor drive for an electric motor receives high frequency AC current, and delivers this current through a converter which is operable to change the current delivered downstream to an inverter and an electric motor.

Abstract: An apparatus for generating a three-phase pulse-width-modulation signal for a three-phase voltage inverter employing a semiconductor switching element includes a generating unit that generates the three-phase pulse-width-modulation signal based on at least one combination of three basic voltage vectors and at least a zero vector.

Abstract: By reduction in loss and noise of a three-phase reactor on the AC side of an electric power converter, compactness and reduction in weight of the reactor are realized, and countermeasures for heat and noise are reduced, and a specific frequency component is reduced, thus cost reduction and conversion efficiency are improved, and carriers of a controller are prepared in correspondence to the phases of the electric power converter, and moreover a phase difference of each carrier is set properly.

Abstract: By reduction in loss and noise of a three-phase reactor on the AC side of an electric power converter, compactness and reduction in weight of the reactor are realized, and countermeasures for heat and noise are reduced, and a specific frequency component is reduced, thus cost reduction and conversion efficiency are improved, and carriers of a controller are prepared in correspondence to the phases of the electric power converter, and moreover a phase difference of each carrier is set properly.

Abstract: A method and device for measuring a switched current (IH) comprises: sensing the switched current (IH) with an AC current transformer to obtain an intermediate measuring signal (VHM); receiving a timing signal indicating on and off periods of the switched current (IH); during an off period, generating an auxiliary signal such that the sum of the intermediate measuring signal and the auxiliary signal is equal to zero; and during an on period, adding the intermediate measuring signal and said the auxiliary signal and providing the sum signal as the output measuring signal, the output measuring signal reflecting an actual value of the AC part and the DC part of the switched current (IH).

Abstract: Apparatus for generating a high time-varying AC voltage using low voltage power semiconductors arranged in series bridge circuits, each powered by an independent DC source. At least one bipolar output pulse width modulation bridge circuit and at least a pair of bipolar output square wave generator bridge circuits have their outputs added together and passed through a low pass filter to form a time-varying, typically sinusoidal, AC output waveform. A first square wave generator has an output with a relative magnitude of 6, a second square wave generator has an output with a relative magnitude of 2 and the pulse width modulator has an output with a relative magnitude of 1. Additional square wave generators of relative magnitude 6 may be added to increase the output voltage.