Abstract

A rapid cutoff device includes a thyristor AC switch for supplying an AC current from a first AC circuit to a second AC circuit. A serially-connected circuit of a first switch and a first capacitor parallel-connects with the first AC circuit. A serially-connected circuit of a second switch and a second capacitor parallel-connects with the second AC circuit. When cutting off the thyristor AC switch, the first switch is operated to conduct the first capacitor in a first direction for the AC current charging to the first capacitor, alternatively, the second switch is operated to conduct the second capacitor in a second direction for the AC current charging to the second capacitor, thereby lowering a current in the thyristor AC switch approaching a zero value and thus rapidly cutting off it.

IPC Classes  ?

• H03K 17/725 - Bipolar semiconductor devices with more than two PN junctions, e.g. thyristors, programmable unijunction transistors, or with more than three electrodes, e.g. silicon controlled switches, or with more than one electrode connected to the same conductivity region, e.g. unijunction transistors for AC voltages or currents
• H03K 17/73 - Bipolar semiconductor devices with more than two PN junctions, e.g. thyristors, programmable unijunction transistors, or with more than three electrodes, e.g. silicon controlled switches, or with more than one electrode connected to the same conductivity region, e.g. unijunction transistors for DC voltages or currents
• H03K 17/04 - Modifications for accelerating switching
• H03K 17/12 - Modifications for increasing the maximum permissible switched current
• H03K 17/10 - Modifications for increasing the maximum permissible switched voltage
• H03K 17/13 - Modifications for switching at zero crossing

Abstract

A shadowing compensation device for a solar cell module has an input port, an isolated DC-DC power converter, and an output port. The input port is connected to two output ends of a solar cell array including multiple solar cell modules connected in series. The output port is connected to one of the multiple solar cell modules of the solar cell array. When one of the solar cell modules connected to the output port of shadowing compensation device has been shaded, the isolated DC-DC power converter outputs a compensating current to the solar cell module that has been shaded for increasing the output voltage of the solar cell module that has been shaded, and increasing the output voltage and output power of the solar cell array.

IPC Classes  ?

• H02M 3/335 - 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
• G01R 31/40 - Testing power supplies
• H01L 31/02 - SEMICONDUCTOR DEVICES NOT COVERED BY CLASS - Details thereof - Details
• H02J 3/38 - Arrangements for parallelly feeding a single network by two or more generators, converters or transformers
• H02M 1/00 - Details of apparatus for conversion

Abstract

A cascade bridge-type DC-AC power converter device includes a low-frequency bridge-type power converter including an AC terminal and a DC bus and a high-frequency bridge-type power converter including an AC terminal. A power conversion method includes: serially connecting the AC terminal of the high-frequency bridge-type power converter and the AC terminal of the low-frequency bridge-type power converter; operating frequency of the low-frequency bridge-type power converter synchronized with frequency of an AC source; and operating the high-frequency bridge-type power converter with high-frequency PWM to generate a multilevel AC voltage. A DC power source connects to the DC bus of the low-frequency bridge-type power converter. No additional power supply circuit will be required for power supply to a DC bus of the high-frequency bridge-type power converter. Accordingly, the power circuit is simplified, and the manufacturing cost is reduced.

IPC Classes  ?

• H02M 5/14 - 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 transformers for conversion between circuits of different phase number
• H02M 7/49 - Combination of the output voltage waveforms of a plurality of converters
• H02M 5/08 - 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 impedances using capacitors only

Abstract

A multilevel AC/DC power converter device includes a high-frequency power converter including a first AC port and a low-frequency power converter including a second AC port and a DC port. A power converting method includes: serially connecting the first AC port of the high-frequency power converter and the second AC port of the low-frequency power converter; operating frequency of the low-frequency power converter synchronized with frequency of an AC power source and operating the high-frequency power converter with high-frequency PWM to generate a multilevel AC voltage; and controlling the multilevel AC voltage to obtain a current of an input AC port being sinusoidal and in a same phase with a voltage of the AC power source. Accordingly, the input power factor approaches unity and the low-frequency power converter supplies a DC voltage to a load via a DC output port.

IPC Classes  ?

• H02M 1/42 - Circuits or arrangements for compensating for or adjusting power factor in converters or inverters
• H02M 7/483 - Converters with outputs that each can have more than two voltage levels
• H02M 7/217 - Conversion of AC power input into DC power output without possibility of reversal 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

Abstract

A control method for bidirectional DC-DC converter includes: operating a bidirectional DC-DC converter having a low voltage side including a plurality of low-voltage-side switches, a voltage clamping switch and a voltage clamping capacitor, and a high voltage side including a plurality of high-voltage-side switches in a boost mode; switching the voltage clamping switch with a predetermined duty cycle prior to switching on all of the low-voltage-side switches; adjusting the predetermined duty cycle of the voltage clamping switch to be smaller than a turn-off interval of the low-voltage-side switches to reduce the conduction loss of the low-voltage-side switches and the voltage clamping switch; alternatively, operating the DC-DC converter in a buck mode; and adjusting and extending the duty cycle of the low-voltage-side switches to overlap a turn-off time of the high-voltage-side switches to reduce the conduction loss of the low-voltage-side switches.

IPC Classes  ?

• H02M 3/335 - 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
• H02M 3/337 - 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 in push-pull configuration
• H02M 1/00 - Details of apparatus for conversion

Abstract

A five-level DC-AC converter includes a capacitor set and a full-bridge circuit. The capacitor set contains two DC capacitors, a power electronic switch and two diodes. When the power electronic switch is turned on/off, the two DC capacitors are connected in series/parallel to provide a two-level DC voltage to the full-bridge circuit. The full-bridge circuit further converts the two-level DC voltage to output a voltage with three voltage levels in the positive half cycle and three voltage levels in the negative half cycle. This achieves the goal of using five power electronic switches to convert DC power into AC power with five voltage levels.

IPC Classes  ?

• H02M 7/5387 - Conversion of DC power input into AC power output without possibility of reversal 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, e.g. single switched pulse inverters in a bridge configuration
• H02M 7/483 - Converters with outputs that each can have more than two voltage levels

Goods & Services

Batteries; Frequency converters; Wave filters for eliminating harmonics; Constant voltage regulators; Rectifiers; Uninterruptible power supplies; Electrical power supplies; Electrical distribution systems, namely, power distribution panels; Transformers; Inverters; DC/AC power converters; Static voltage regulators.

Abstract

An estimation method for residual discharging time of batteries includes the steps of: providing a set of battery-discharge-current intervals and a set of battery-discharge equations, setting the discharge time of each battery-discharge-current intervals at zero; detecting a discharge current, voltage and time of batteries; judging whether the discharge current exceeds all of the battery-discharge-current intervals; selecting one of the battery-discharge-current intervals and the associated battery-discharge equation according to the detected discharge current; calculating an estimation of residual discharging time; accumulating and recording the discharge time; judging whether the discharge voltage is lower than a predetermined value and calculating an estimation error of the residual discharging time; and adjusting parameters of the battery-discharge equation for reducing the estimation error of the residual discharging time if the estimation error is greater than a predetermined error value.

IPC Classes  ?

• H02J 7/00 - Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
• H02J 7/04 - Regulation of the charging current or voltage
• G01R 31/36 - Arrangements for testing, measuring or monitoring the electrical condition of accumulators or electric batteries, e.g. capacity or state of charge [SoC]

Abstract

A three-leg power converter apparatus including first, second and third input/output ports, a three-leg bridge converter, a filter circuit, a decoupling circuit and a controller is presented. The three-leg bridge converter has three single-leg circuits, two DC terminals connecting to two terminals of the first input/output port, and three mid-terminals with each of them being formed by a middle point of one of the three single-leg circuits. The controller connects to the three-leg bridge converter for controlling an input or output current passing through each DC terminal and mid-terminal. The filter circuit connects between two of the mid-terminals and the second input/output port. The decoupling circuit has two terminals connecting to the second input/output port and another terminal connecting to a terminal of the third input/output port, with the third input/output port having another terminal connecting to the other mid-terminal that dose not connect with the filter circuit.

IPC Classes  ?

• H02M 3/24 - Conversion of DC power input into DC power output with intermediate conversion into AC by static converters
• G05F 1/10 - Regulating voltage or current

Abstract

A ripple voltage suppression apparatus includes a DC/DC converter and a control circuit. The DC/DC converter has a power electronic switch. The control circuit has a voltage detector detecting a DC output voltage of the DC/DC converter, a ripple voltage suppression circuit receiving the detected DC output voltage to generate an AC control signal for controlling an AC component of a duty ratio of the power electronic switch, an output voltage regulation circuit receiving the detected DC output voltage to generate a DC control signal for controlling an DC component of a duty ratio, an adder adding the AC and DC control signals to form a combined control signal, and a PWM circuit converting the combined control signal into a PWM signal to control the power electronic switch. Only the DC output voltage of the DC/DC converter has to be detected for the control circuit.

IPC Classes  ?

• H02M 1/14 - Arrangements for reducing ripples from DC input or output
• H02M 7/42 - Conversion of DC power input into AC power output without possibility of reversal

Abstract

A bi-directional DC to DC power converter includes two DC sources, two inductors respectively connected to the two DC sources, a first switch and a second switch respectively connected to the two inductors, two capacitors respectively connected to the two switches, and a third switch connected between the two inductors. The first, second and third switches are respectively connected reversely with a diode in parallel. When the third switch is alternately turned on and off and the first and second switches are always turned off, the power converter operates as a boost power converter and electric energy flows from the two DC sources to the two capacitors. When the third switch is always turned off and the first and second switches are synchronously turned on or off, the power converter operates as a buck power converter and electric energy flows from the two capacitors to the two DC sources.

IPC Classes  ?

• H02M 7/5387 - Conversion of DC power input into AC power output without possibility of reversal 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, e.g. single switched pulse inverters in a bridge configuration
• H02M 3/156 - Conversion of DC power input into DC power output without intermediate conversion into AC 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 or current, e.g. switching regulators
• G05F 1/577 - Regulating voltage or current wherein the variable actually regulated by the final control device is DC using semiconductor devices in series with the load as final control devices for plural loads

Abstract

A modularized active power filter includes a control module and at least one power module. The control module automatically identifies the number of parallel connected power modules and generates one set of PWM signals to correspondingly control the parallel connected power modules, so as to provide a final compensation current by a single power module or by plural power modules. Thereby, the compensation demand of a load is met. Consequently, the modularized active power filter is able to improve flexibility of compensation capacity, to shorten the time for service, to be suitable for mass production, and to lower the manufacturing cost.

IPC Classes  ?

• H02M 1/12 - Arrangements for reducing harmonics from AC input or output

Abstract

An active power conditioner includes a first power electronic switch set, a second power electronic switch set, a third power electronic switch set, an input filter and an output filter. The active power conditioner can supply a stable AC voltage to a load when a voltage variation occurs at an AC power source by controlling either the second power electronic switch set or the third power electronic switch set via high-frequency switching, and the other power electronic switch sets that are not switched in high frequency are controlled to switch in low-frequency switching.

IPC Classes  ?

• G05F 1/70 - Regulating power factorRegulating reactive current or power

Abstract

An active power filter includes an energy storage capacitor, an inverter, a filtering circuit and a controller. The inverter is controlled to act as a virtual resister at a fundamental frequency for compensating for the power loss of the active power filter, to act as a virtual capacitor at a fundamental frequency for compensating for a fundamental reactive power of the load, and/or to generate a harmonic current for suppressing the harmonic currents of specific orders of the load.

IPC Classes  ?

• H02M 1/10 - Arrangements incorporating converting means for enabling loads to be operated at will from different kinds of power supplies, e.g. from AC or DC
• H02M 1/12 - Arrangements for reducing harmonics from AC input or output
• H02M 1/44 - Circuits or arrangements for compensating for electromagnetic interference in converters or inverters

Abstract

A maximum power point tracking method, applied to a tracking device, employs a DC/DC converter connecting with a solar cell array, and including a controller actuating the DC/DC converter to perform an active resistance characteristic; a maximum power point tracking circuit adjusting the active resistance of the DC/DC converter; monitoring a change of an output power of the solar cell array in determining a direction for adjusting the active resistance of the DC/DC converter; and the maximum power point tracking circuit repeatedly adjusting the active resistance of the DC/DC converter. If the change of the output power of the solar cell array is positive, the active resistance of the DC/DC converter is adjusted in the same direction; but, conversely, if the change of the output power of the solar cell array is negative, the active resistance of the DC/DC converter is adjusted in an opposite direction.

IPC Classes  ?

• G05F 5/00 - Systems for regulating electric variables by detecting deviations in the electric input to the system and thereby controlling a device within the system to obtain a regulated output
• G05F 1/40 - Regulating voltage or current wherein the variable is actually regulated by the final control device is AC using discharge tubes or semiconductor devices as final control devices
• H02M 7/00 - Conversion of AC power input into DC power outputConversion of DC power input into AC power output

Goods & Services

Battery; frequency converter; wave filter; constant voltage regulator; commutator; uninterruptible power supplies; electronic distributor panels; electrical transformers; static current transformer; PV Inverter.

Goods & Services

Constant voltage regulator; commutator; uninterruptible power supply; wave filter for eliminating harmonics; battery; static current transformer; electronic distributor panels; frequency converter; transformer; PV inverter

Abstract

An islanding detection apparatus for a distributed generation power system and a detection method therefor operates a power converter to act as a virtual capacitor or inductor at a frequency close to but unequal to that of a utility power system under abnormal condition of the utility power system. When power failure occurs in the utility power system, only the distributed generation power system supplies power to a load so that a load voltage has been changed in at least one of amplitude and frequency which can be immediately detected islanding phenomenon.

IPC Classes  ?

• H02J 9/00 - Circuit arrangements for emergency or stand-by power supply, e.g. for emergency lighting

Goods & Services

Constant voltage regulators; commutators; UPSs (uninterruptible power supply); wave filters; batteries; static current transformers; distributors; frequency converters; transformers.

Goods & Services

Uninterruptible electrical power supplies for all power sensitive electronics devices such as computers, telecommunication equipment, and medical equipment

Goods & Services

CONSTANT VOLTAGE REGULATOR, COMMUTATOR, UNINTERRUPTIBLE POWER SUPPLIES, WAVE FILTER, BATTERY; STATIC CURRENT TRANSFORMER; ELECTRONIC DISTRIBUTOR PANELS; FREQUENCY CONVERTER; ELECTRICAL TRANSFORMERS

Goods & Services

Constant voltage regulators; commutators; UPS (uninterruptible power supply devices); wave filters; batteries; static current transformers; distributors; frequency converters; transformers.

Goods & Services

Uninterruptible Power Supply.