223 results about "Boost chopper" patented technology

In a circuit apparatus for transformerless conversion of an electric direct voltage of a two-pole direct voltage source (1) connected to ground having a first voltage pole (+) and a second voltage pole (−) into an alternating voltage, hazardous capacitive leakage currents are avoided by connecting the direct voltage source (1) to ground and the DC-AC converter (400) is operated at a controlled intermediate circuit voltage, a DC-DC converter stage (300) being connected between the direct voltage source (1) and the DC-AC converter (400), said DC-DC converter stage providing at its output a + / − voltage that is symmetrical with respect to the grounding point, two series-connected capacitors (41, 42) having the same polarity and being connected to ground at their connecting point (V) and controlled are charged by two buck-boost choppers (100, 200) connected one behind the other.

A bypass control section (6) maintains a bypass switch (5) in the ON state during the period when a battery voltage (Vi) is higher than the output voltage (Vo) to an external load (L). Upon falling of the output voltage (Vo) at a desired voltage (ET), a converter control section (4) starts switching control at once, and a step-up chopper (3) promptly starts boost operation. The bypass control section (6) maintains the bypass switch (5) in the ON state from the start of the boost operation of the step-up chopper (3) until the match between the battery voltage (Vi) and the output voltage (Vo).

In an insulation type AC-dc converter in which input current from a commercial power supply is converted to obtain insulated direct current, the overall efficiency is raised and the structure is simplified. A multi-resonance type half-bridge DC-DC converter having an insulation transformer T is used as a first converter, and a boosting chopper circuit for power factor improvement is used as a second converter. Hence through multi-resonance operation, increases in losses can be suppressed even when the switching frequency is raised, and because a half-bridge circuit is used, switching elements and similar with lower voltage ratings can be employed, whereby overall efficiency can be increased. Moreover, a voltage substantially similar to the full-wave rectified waveform of the power supply voltage is obtained from the output capacitor at the boosting chopper circuit input, whereby there is no need for a feed-forward circuit across the insulation transformer, and moreover the electrolytic capacitor which had to be provided on the converter input side is unnecessary. This is advantageous for achieving miniaturization and a thin design.

A bypass control section (6) maintains a bypass switch (5) in the ON state during the period when a battery voltage (Vi) is higher than the output voltage (Vo) to an external load (L). Upon falling of the output voltage (Vo) at a desired voltage (ET), a converter control section (4) starts switching control at once, and a step-up chopper (3) promptly starts boost operation. The bypass control section (6) maintains the bypass switch (5) in the ON state from the start of the boost operation of the step-up chopper (3) until the match between the battery voltage (Vi) and the output voltage (Vo).

A boost chopper circuit converts AC power to DC voltage and supplies the DC voltage to a load. The boost chopper circuit includes a switching element and a reactor. A controller ON / OFF controls the switching element based on a comparison result in an interval of the former half of a half cycle of the AC power between a detected input current by a input current detector and a current instruction value of a modeling waveform obtained by reducing a harmonic component of a predetermined order from the current waveform.

The present invention relates to a method and a control system for driving a three-strand brushless, electronically commutated electric motor (2), wherein a line AC voltage (UN) is rectified and fed via a slim DC link (8) with minimum DC link reactance as a DC link voltage (UZ) to an inverter (10) that can be driven to supply and commutate the electric motor (2). A pulsating DC voltage (UG) initially generated by rectifying the line AC voltage (UN) is dynamically increased with respect to its instantaneous values by a step-up chopper (18) in such a manner that the resulting DC link voltage (UZ) with a reduced ripple always lies above a defined limit voltage (U18 / U1) over time. The control system consists of a network rectifier (6), a downstream slim DC link (8) with minimum DC link reactance and a controllable inverter (10) that can be supplied via the DC link and driven to commutate the electric motor (2). A step-up chopper (18) is integrated therein with a controller (20) designed in such a manner that, the pulsating DC voltage (UG) rectified by the network rectifier (6) is dynamically increased with respect to its instantaneous values in such a manner that the resulting DC link voltage (UZ) with a reduced ripple always lies above a defined limit voltage (U20 / U1) over time. Stray inductances (Ls1-Ls3) of the motor winding heads present in the electric motor (2) are used as inductor (L) for the step-up chopper (18).

In a circuit apparatus for transformerless conversion of an electric direct voltage of a two-pole direct voltage source (1) connected to ground having a first voltage pole (+) and a second voltage pole (−) into an alternating voltage, hazardous capacitive leakage currents are avoided by connecting the direct voltage source (1) to ground and the DC-AC converter (400) is operated at a controlled intermediate circuit voltage, a DC-DC converter stage (300) being connected between the direct voltage source (1) and the DC-AC converter (400), said DC-DC converter stage providing at its output a + / − voltage that is symmetrical with respect to the grounding point, two series-connected capacitors (41, 42) having the same polarity and being connected to ground at their connecting point (V) and controlled are charged by two buck-boost choppers (100, 200) connected one behind the other.

The present invention provides a power supply circuit comprises a rectifier circuit (2) for converting an AC voltage to a DC voltage, a boost chopper circuit (3) for boosting an output voltage of the rectifier circuit based on a duty ratio signal; a smoothing circuit (4) for smoothing an output voltage of the boost chopper circuit; and a control means (5) for creating the duty ratio signal, the control means (5) is provided with a function for generating a DC voltage ripple information of the smoothing circuit, and correcting or modifying the duty ratio signal based on the DC voltage ripple information.

A boost chopper circuit converts AC power to DC voltage and supplies the DC voltage to a load. The boost chopper circuit includes a switching element and a reactor. A controller ON / OFF controls the switching element based on a comparison result in an interval of the former half of a half cycle of the AC power between a detected input current by a input current detector and a current instruction value of a modeling waveform obtained by reducing a harmonic component of a predetermined order from the current waveform.

In a switching power supply device, the operating voltage is supplied to the power-factor improvement control circuit when the switching power supply device is operating under normal operating load. Thereby, the booster chopper circuit is controlled by the power-factor improvement control circuit so as to improve the power factor of the device. By contrast, during the non-oscillation period while the switching control circuit is in the intermittent oscillation mode when the power consumption is small, the voltage induced in the auxiliary winding drops. Accordingly, the voltage of the auxiliary power supply also drops. Furthermore, when the driving voltage to be supplied to the power-factor improvement control circuit is reduced below the operating voltage thereof by the voltage reduction circuit, the power-factor improvement control circuit stops functioning, thereby reducing power consumption accordingly.

A current transformer for energy conversion in a super-conductive energy storage system utilizes a two-stage boost-chopper to fulfill boost control for discharge process in super-conductive energy storage magnets. The first stage of the chopper circuit adopts a plurality of metal oxide semi-conductor field-effect transistors in parallel connection, so that the voltage on both ends of a super-conductive magnet can be limited in a rather low voltage level to meet the insulation requirements of the super-conductive magnet. The second stage of the chopper circuit increases the voltage to a higher level, and utilizes IGBTs as switch components to regulate subsequent output voltage through adjusting the switch duty cycle of the IGBTs through a PWM control mode, so as to fulfill the adjustable target for subsequent output voltage and the controllable target of the super-conductive magnet discharge voltage. The invention can realize energy output in the super-conductive energy storage magnet in a constant-voltage and DC mode, in order to meet the requirements for subsequent voltage-type loads. Meanwhile, the output voltage of the current transformer is not limited by insulating strength of magnets, but can fulfill flexible regulation according to subsequent load, and meanwhile, avoid the large volume problems with transformers or the multiple circuit topology structure.

A power supply device includes a first semiconductor switching device for controlling an alternating input current waveform, a smoothing capacitor to which a rectified voltage is applied, and an inverter that converts the rectified voltage into alternating current via a step-up chopper. The step-up chopper includes an inductor and a diode connected between the smoothing capacitor and inverter, and a second semiconductor switching device connected to the inductor and diode. The power supply device further includes an instantaneous voltage drop compensation function whereby the energy of the smoothing capacitor is supplied by an operation of the step-up chopper to the inverter when there is an instantaneous voltage drop in an alternating current power supply voltage. MOSFETs with a breakdown voltage lower than that of the first semiconductor switching device are connected between terminals of the step-up chopper, thus further reducing loss in comparison with when a bypass diode is used.

A chopping double-DSP digital speed governing system of a medium voltage motor having an IGBT inverter comprises an uncontrollable rectifier, a boosting chopper and an IGBT inverter. The boosting chopper and the IGBT inverter are controlled through two internal ring current controllers. The speed of an external ring of the speed governing system and the voltage of an external ring of the inverter are controlled through two DSPs. The speed governing system and a motor system are controlled in a programmable way through a programmable controller. The system is applicable for ordinary wound asynchronous motors, internal feedback wound asynchronous motors, wound-cage brushless doubly-fed motors and wound-cage internal feedback brushless motors, and eliminates the problem of damaging equipments because of inversion resulting from grid failure out and out. The invention is highly reliable, is simple and convenient to be used, has excellent man-machine interface, can achieve remote monitoring and management, is highly digitalized, saves energy and is environmentally protective; the control error is small; the means of communication is flexible; and the cost is low.

A power converter 1 includes a first conversion circuit 10 connected with a first winding n1 of a transformer 40, and a second conversion circuit 20 connected with a second winding n2 of the transformer 40. The first and second conversion circuits 10 and 20 are configured to perform bidirectional power conversion. The power converter further includes a third conversion circuit 30 that is a circuit provided at a pre-stage of the first conversion circuit 10 in a direction of transferring electric power toward the second conversion circuit 20 from the first conversion circuit 10. The third conversion circuit 30 is configured to perform bidirectional power conversion, and function as a boosting chopper circuit upon transferring electric power toward the second conversion circuit 20 from the first conversion circuit 10.

The invention discloses a power supply device for a DUT in an integrated circuit test system. A PC host computer sets a preset output value of the system according to the needs of the integrated circuit test system, and sends the preset output value to a controller MCU; the controller MCU controls a chopper circuit to output a corresponding voltage value for a power amplifier according to the preset output value of the system, and the integrated circuit test system is thus controlled to operate. When the integrated circuit test system is controlled to operate, a voltage / current sampling circuit collects voltage and current values, the values are fed back to the controller MCU, the controller MCU processes the deviation value of the preset output value and the sample value through a built-in feedback control algorithm, the output voltage of a BUCK / BOOST chopper circuit is further controlled through the deviation value, and thus, the output power precision is controlled and adjusted, thepower dissipation of the power amplifier is reduced, and the load driving capability of the power amplifier is improved.

A semiconductor switching device includes a power control part, which includes a voltage dropping chopper circuit having a first switching element and a first diode, a voltage boosting chopper circuit having a second switching element and a second diode, and an inductance. And the inductance is connected such that an unusual current caused by the arm short circuit is forced to pass through the inductance.

In an insulation type AC-dc converter in which input current from a commercial power supply is converted to obtain insulated direct current, the overall efficiency is raised and the structure is simplified. A multi-resonance type half-bridge DC-DC converter having an insulation transformer T is used as a first converter, and a boosting chopper circuit for power factor improvement is used as a second converter. Hence through multi-resonance operation, increases in losses can be suppressed even when the switching frequency is raised, and because a half-bridge circuit is used, switching elements and similar with lower voltage ratings can be employed, whereby overall efficiency can be increased. Moreover, a voltage substantially similar to the full-wave rectified waveform of the power supply voltage is obtained from the output capacitor at the boosting chopper circuit input, whereby there is no need for a feed-forward circuit across the insulation transformer, and moreover the electrolytic capacitor which had to be provided on the converter input side is unnecessary. This is advantageous for achieving miniaturization and a thin design.

A numerical physical hybrid simulation system of a grid-connected photovoltaic power generating system comprises an RTDS digital system, a DSP physical system, an analog quantity output card and a digital quantity input card, wherein a direct-current voltage signal and a direct-current current signal which are output by a photovoltaic cell panel in the RTDS digital system are transmitted and input to the DSP physical system through the analog quantity output card, and a PWM pulse driving a boost chopper circuit in the DSP physical system is transmitted and input to the RTDS digital system through the digital quantity input card. The numerical physical hybrid simulation system can accurately track the global maximum power point in a local shadow, a standby circuit is needless, the system is suitable for various extreme light conditions, and result accuracy and reliability are improved.

The invention provides a pulverized coal feeder frequency converter control system with a low voltage ride-through power supply device and relates to the field of pulverized coal feeder frequency converter control. The pulverized coal feeder frequency converter control system with the low voltage ride-through power supply device aims to solve the problems that when a pulverized coal feeder frequency converter control system encounters low system voltages, a pulverized coal feeder stops running, and changes of rotating speed, changes of torque and changes of power are caused. According to the pulverized coal feeder frequency converter control system with the low voltage ride-through power supply device, three-phase alternative current power energy passes through a second three-phase switch and a first contactor and is fed into a rectification loop formed by a first three-phase inducer and a diode rectification bridge, the three-phase alternative current power energy is transformed to direct current power energy and is stored in a first capacitor and a second capacitor, a BOOST type boost chopper circuit is formed by a second three-phase inducer and a three-phase inverter circuit, the direct current power energy on the first capacitor and the second capacitor can be transformed to direct current power energy with a higher voltage class, and the direct current power energy with the higher voltage class is stored in a third capacitor and a fourth capacitor and is fed into a frequency converter. A pre-charging loop is formed by a second contactor and three resistors of another set, and stable charging for the first capacitor, the second capacitor, the third capacitor and the forth capacitor when a voltage detecting module is powered on initially is achieved. The pulverized coal feeder frequency converter control system with the low voltage ride-through power supply device is applied to pulverized coal feeder control systems of boilers.

The invention discloses a multi-energy collecting wireless sensor network node power source which comprises an energy collecting module, a power selecting module, a charging control module, a discharging management module and a control core. The energy collecting module collects solar energy, wind energy and water energy from the environment through a small solar cell panel, a wind power generator and a water power generator and enables the energy to be converted into electric energy. The power selecting module selects one kind of the environment energy to supply power according to judgment on the output power. The maximum energy tracking algorithm is used in the charging control module, and the duty ratio of a direct current boosting chopper circuit is controlled through PWM waves changed along with the output power to improve the charging efficiency. The discharging management module can select proper output voltage and provide stable energy supply. The multi-energy collecting wireless sensor network node power source is small in size, low in cost, low in power consumption, capable of guaranteeing that a node can have stable energy supply under different environmental conditions and capable of effectively prolonging the service life of the node.

AC-DC converter is provided which comprises an auxiliary winding 8c in a transformer 8, a voltage detector 21 for detecting a voltage VN appearing on auxiliary winding 8c of transformer 8 by on-off operation of a main switching element 9 in a DC-DC converter 10 to produce an output signal VCP1 when voltage VN on auxiliary winding 8c has a negative polarity, a waveform shaper 23 for generating chopping signals VRC from output signal VCP1 of voltage detector 21, and a PWM circuit 27 for comparing output voltage VRC from waveform shaper 23 and output voltage VCH from a boosting chopper 3 to supply drive signals VG1 to step-up switching element 5 in boosting chopper 3 when output voltage VRC from waveform shaper 23 exceeds output voltage VCH from boosting chopper 3. While controlling fluctuation in output voltage from boosting chopper with respect to fluctuation in AC input voltage, the converter can improve input power factor relative to AC voltage and also reduce consumption power during light load period.

The invention relates to a wide-input voltage range arc power-supply device. A wide-range commercial power voltage is divided into a low-voltage module voltage, a medium-voltage module voltage and a high-voltage module voltage after rectified, filtered and stabilized, the low-voltage module voltage is boosted and the high-voltage module voltage is bucked as well as the medium-voltage module voltage is directly connected by a booster chopper circuit and a cascade voltage-reducing chopper, and then the low-voltage module voltage, the medium-voltage module voltage and the high-voltage module voltage are inverted by one group of inverters for obtaining the single voltage value with the required frequency so as to be used by an inversion type electric welder, and the single voltage value can be connected with the single-phase / three-phase power supply voltage, thus the flexibility is stronger.

In a reversible buck-boost chopper circuit, a first half-bridge circuit has a first switching element with a high-side main electrode connected to a positive electrode of a DC power source, and a second switching element is connected to the first switching element at a first output terminal. A low-side main electrode of the second switching element is connected to a negative electrode of the DC power source. A second half-bridge circuit has a third switching element with a high-side main electrode connected to a high-side terminal of the load. A fourth switching element of the second half-bridge circuit is connected to the third switching element at a second output terminal. A low-side main electrode of the fourth switching element is connected to a low-side terminal of the load and the negative electrode. A reactor is connected between the first and second output terminals.

The invention relates to a great-power wind-power integration convertor suitable for a cage asynchronous generator, belonging to the technical field of new energy of wind and power. The invention adopts the technical scheme that a rectifying unit comprises at least one three-phase uncontrolled diode rectifier unit or a plurality of three-phase uncontrolled diode rectifier units connected in parallel, a boost chopper unit comprises at least one boost chopper unit or a plurality of boost chopper units connected in parallel, an inverter unit comprises at least one three-phase full-control inverter unit or a plurality of three-phase full-control inverter units connected in parallel, and a motor soft-start excitation unit comprises at least one three-phase soft-start excitation unit or a plurality of three-phase soft-start excitation units connected in parallel. By applying the low-cost cage asynchronous generator to wind-powered generation, the whole unit cost is greatly decreased, the control structure is simplified, and the stability and the suitability of the unit operation are enhanced.

The invention belongs to the technical field of power electronics and relates to a novel boost chopper cascade structure. The novel boost chopper cascade structure comprises a boost chopper and a filter energy-storage capacitor connected with the output end of the boost chopper, wherein the boost chopper consisting of the cascade structure comprises n boost chopper units which are built according to a regular circuit and cascading diodes and commutation power switching tubes which are connected between the boost chopper units; and the output ends of the n boost chopper units are connected in series with one another by commutation power switching tubes. The novel boost chopper cascade structure has the advantages of simple structure and high expandability.

A light emitting element drive device of the present invention includes a light emitting element; a drive unit for driving the light emitting element; an electricity storage element capable of storing electric power; a battery power supply capable of supplying electric power to the electricity storage element; and a boost chopper circuit having an inductor, for boosting voltage by opening and closing a switching element. The drive unit is switchable between three states: a storing state in which electric power from the battery power supply is stored in the electricity storage element; a first discharging state in which the electric power stored in the electricity storage element is supplied to the light emitting element; and a second discharging state in which electric power from the battery power supply is boosted by the boost chopper circuit and is supplied to the light emitting element.

A boost converter is configured of a boost chopper having a diode of an upper arm and a switching element of a lower arm. Output power from a battery to a load is limited such that a current flowing through boost converter does not exceed a current upper limit value for thermal protection of boost converter. The current upper limit value is set based not only on a cooling water temperature of boost converter but also on an output voltage VH of boost converter, in consideration of characteristics that, as output voltage VH rises, an amount of heat generated in diode decreases, diode being regarded as a main target of thermal protection since it receives a power running current to load. Thereby, the boost converter can be protected from overheating without excessively deteriorating vehicle traveling performance.

The invention provides a string inverter and a boost chopper circuit control method thereof, and the method comprises the steps: firstly, determining a corresponding first PV voltage interval when a current ripple is greater than a threshold value according to a preset ripple current condition; performing PWM control on the boost chopper circuit at a first switching frequency in the first PV voltage interval; and performing PWM control on the boost chopper circuit at a frequency lower than the first switching frequency in other voltage intervals except the first PV voltage interval. Namely, when PWM control is carried out on the boost chopper circuit, control is carried out in a PV voltage interval with relatively high current ripples by adopting relatively high switching frequency, so that the current ripples are reduced. In a PV voltage interval with relatively small current ripple, relatively low switching frequency is adopted for control, so that the switching loss is reduced, therefore, two restriction conditions of current ripples and switching loss can be compatible.