41results about How to "Extended dead time" patented technology

A power converter employing a controller configured to increase a dead time between conduction periods of first and second power switches therein and method of operating the same. In one embodiment, the power converter includes first and second power switches coupled to an input thereof, and a sensor configured to provide a sensed signal representative of at least one of a current level and a power level of the power converter. The power converter also includes a controller configured to increase a dead time between conduction periods of the first and second power switches when the sensed signal indicates a decrease of at least one of the current level and the power level of the power converter.

To provide a DC-DC converter allowing miniaturization of a voltage transformer without fear of reducing conversion efficiency due to saturation of the transformer and allowing enhancement of conversion efficiency by suppressing switching loss. An LC resonance circuit 3 is inserted on the secondary side of a transformer 1. When driving means 4 alternately turn on and off a pair of switching means 2-1, 2-2, an output is obtained on the secondary side via the transformer 1. A current transformer 5 for current detection, a current value detection portion 6 and a current value comparison portion 7 detect a difference between each resonance current value per half cycle due to the operation of the LC resonance circuit 3. In response to its result, the drive means 4 regulate automatically on-state duty ratio of the switching means 2-1, 2-2 so as to align the resonance current values per half cycle.

To provide a DC-DC converter capable of suppressing switching loss with a simple structure, and capable of enhancing converting efficiency.

An LC resonant circuit 3 is inserted on a secondary side of a transformer 1. If switching means 2 is turned ON or OFF by driving means 4, output can be obtained on the secondary side through the transformer 1. A resonant current frequency detecting means comprises a current detecting current transformer 5 and a frequency detecting unit 6. The resonant current frequency detecting means detects resonant current frequency caused by operation of the LC resonant circuit 3. This frequency is fed back to the driving means. As a result, the driving means 4 turns the switching means 2 ON or OFF at a frequency corresponding to the resonant frequency of the LC resonant circuit 3.

The invention discloses a C80 autoclaving-free concrete pole production technology which comprises the following steps of: (1) mixing materials, namely uniformly stirring components of concrete by a secondary stirring mode; (2) forming, namely pouring the mixed material mixed to a pole steel mould for centrifugal shaping, and meanwhile sampling and preparing a test block; (3) performing steam maintenance, namely placing the pole and the test block to a maintenance pool for constant pressure steam maintenance; and (4) detecting, namely demoulding the test block and detecting one-day strength and seven-day strength, respectively. According to the C80 autoclaving-free concrete pole production technology provided by the invention, the autoclaving link of concrete can be omitted in the production process of high strength poles, so that energy consumption can be reduced. Autoclaving is omitted, so that concrete is prevented from being damaged by autoclaving, and the product durability is ensured. The technology can be further widely applied to tubular pipe production and has god economical and social benefits as well as good popularization prospect.

A switching power supply includes an insulated transformer, a full-bridge circuit which converts input DC power into AC power and outputs the AC power to a primary-side coil, an output circuit which converts AC power input from secondary-side coils into DC power and outputs the DC power, and a control circuit which controls the full-bridge circuit by using a phase shift method based on voltage output by the output circuit. When a measured value of the amount of phase shift determined from at least one of the voltage and current output by the output circuit is smaller than a theoretical value of the amount of phase shift corresponding to the switching power supply operating in a continuous current mode, the control circuit prolongs dead time used in the full-bridge circuit in accordance with the difference between the measured value and the theoretical value.

A gas shower device having gas curtain comprises a first gas shower unit for injecting a reaction gas, thereby forming a reaction gas region, and a second gas shower unit. The second gas shower unit arranged around a periphery of the first gas shower unit comprises a buffer gas chamber for providing a buffer gas, and a curtain distribution plate. The curtain distribution plate further comprises a plurality through holes for injecting the buffer gas, thereby forming a gas curtain around a periphery of the reaction gas region. In another embodiment, an apparatus for depositing film is provided by utilizing the gas shower device having gas curtain, wherein the gas curtain prevents the reaction gas in the reaction gas region from being affected directly by a vacuum pressure so that a residence time of reaction gas can be extended thereby increasing the utilization of reaction gas and film-forming efficiency.

In a unit inverter system where multiple unit inverters are connected in parallel, the quantity of operating unit inverters is determined in accordance with an amount of power to be converted. A gate signal of a semiconductor switching element of a unit inverter is turned off after an output current of the inverter is reduced when reducing the quantity of inverter units, thereby improving the partial load efficiency of the system without an adverse effect on the system. A regulator connected to the inverter determines dead time of the inverter according to the output current value and an average output current value of the unit inverters, waits for the determined dead time so as to reduce the output current of the unit inverter, and then turns off the gate signal.

The invention relates to the technical field of waste gas circulating heating devices, in particular to a high-temperature hot air device suitable for waste gas circulation heating of a brick kiln. The high-temperature hot air device comprises a hot air flow channel and a heater arranged in the hot air flow channel; the hot air flow channel comprises an air blower, an air inlet pipe, an outer cylinder body, an inner cylinder body and a rotating body, wherein the inner cylinder body is arranged in the outer cylinder body, an outer flow channel is formed between the outer cylinder body and the inner cylinder body, nozzles are evenly distributed on the top of the inner cylinder body, and the rotating body is arranged in the inner cylinder body. According to the high-temperature hot air devicesuitable for waste gas circulation heating of the brick kiln, the principle of fluid mechanics and aerodynamics is fully utilized, and an 80-degree inclined plane, a diffuser pipe heat flow channel,an impeller inner bottom plate flow mixing device, a four-leg supporting device and the like are adopted in the structure, so that not only is water contained in waste gas further removed, but also the waste gas is fully mixed in the heating area and keeps the long stagnation time, the waste gas is sufficiently heated, the heating efficiency is improved, and the energy consumption is reduced.

An improved high input voltage instant start electronic ballast uses a substantially lossless snubber circuit. The substantially lossless snubber circuit is incorporated into the ballast to reduce turn off losses and increase the efficiency of the ballast. The snubber circuit includes two capacitors connected in parallel with respect to the two switching transistors or FETS in the inverter of the ballast. A series-resonant lamp voltage sensing circuit is also provided that uses a voltage dividing capacitor to accomplish lossless monitoring of the open circuit voltage of the ballast. A cable compensation circuit minimizes variations in the open circuit voltage due to the connecting and disconnecting of a cable to the ballast by limiting the turn on times of the transistors during high voltage conditions.

The invention discloses a rotary load switch contact arc extinguishing system of a sulfur hexafluoride (SF6) ring main unit. The system comprises a static contact, a dynamic contact corresponding to the static contact and a driving mechanism for driving the dynamic contact to move; a static contact insulating seat is arranged on the static contact; a plurality of metal grids are inlaid on the static contact insulating seat side by side; and an arc spacing plate is arranged between three-phase contacts. The load switch has simple process, strong arc extinguishing capacity and good on-off stability of transfer current, and meets the requirement of 1750A disjunction by test.

The invention provides a lakeside zone for intercepting and purifying non-point source pollution. A first step land, a first depression land, a second step land, a second depression land, a third stepland and a third depression land are sequentially arranged outwards along a lake area, and a flow guide pipe is embedded in the bottom of the third step land; the cross sections of the three stages of step lands are trapezoidal, and the elevations of the three stages of step lands are increased step by step; the cross sections of the first depression land and the second depression land are inverted trapezoids, the cross section of the third depression land is concave, and the elevations of the three stages of depression lands are increased step by step; flood-tolerant emergent aquatic plantsare planted on the first step land, and drought-tolerant emergent aquatic plants are planted on the second step land and the third step land; and floating plants are planted in the first depression land, flooding-resistant emergent aquatic plants are planted in the second depression land, and turf is planted in the third depression land. According to the method, the terrain of the lakeside zone isreconstructed into multiple stages of step lands and depression lands, so that the stagnation time of non-point source pollution on the lakeside zone can be effectively prolonged, the non-point source pollution is prevented from directly entering the lake area, and favorable conditions are created for absorption and purification by aquatic plants in the lakeside zone.

The invention relates to a driving signal processing device and a motor system. The driving signal processing device comprises a dead zone detection circuit, a signal rising edge detection circuit, a signal delay circuit and a control unit. According to the invention, the dead zone detection circuit can detect the dead zone indication signal indicating whether the target dead zone duration is abnormal, the rising edge detection signal can be obtained based on the signal rising edge detection circuit, and then the control signal for performing delay control on the signal delay circuit is generated based on the dead zone indication signal and the rising edge detection signal. Therefore, when the signal time-delay circuit is triggered by the control signal, the upper and lower bridge arm driving signals can be subjected to time-delay processing to obtain the delayed driving signal, and the purpose of prolonging the time length of the dead zone by performing time-delay processing on the rising edge of the upper and lower bridge arm driving signals under the condition that the time length of the target dead zone is too short can be achieved.

The invention provides a viscosity reduction and solid removal integrated device for catalytic cracking oil slurry. The viscosity reduction and solid removal integrated device can effectively carry out viscosity reduction and solid removal treatment on the catalytic cracking oil slurry. The viscosity reduction and solid removal integrated device comprises an ultrasonic viscosity reduction tank, electrostatic separation tanks, a constant-temperature water bath tank and an oil storage tank; the constant-temperature water bath tank is arranged above the oil storage tank through a supporting frame, the ultrasonic viscosity reduction tank is arranged above the constant-temperature water bath tank through a supporting frame, and the electrostatic separation tanks are mounted in the constant-temperature water bath tank; the ultrasonic viscosity reduction tank is communicated with the electrostatic separation tanks through hoses, the electrostatic separation tanks are communicated with the oil storage tank through hoses, and the oil storage tank is fixedly mounted through a leg type base; and the plurality of electrostatic separation tanks are arranged in the constant-temperature water bath tank, and the upper surface and the tank bottom surface of the separation tank end cover of each electrostatic separation tank are higher than the upper surface and the lower surface of the constant-temperature water bath tank.

To operate the internal combustion engine, a defined forced excitation is applied to the air ratio, which serves as the basis for the setpoint of the lambda controller. During the diagnostic mode, the diagnostic function (DIAGF) is used to determine whether there is a probe error (SOND_ERR) in the exhaust gas probe. If a probe fault is detected (SOND_ERR), the value of the measurement signal is detected as a start value (STW) in time relative to the edge of the setpoint curve of the lambda controller, after a defined first time period (TD1) The current value of the measurement signal is then detected as an end value (EW). From the start value (STW) and the end value (EW) it is known whether there is a filter fault (FIL_ERR) or an invalid time fault of the exhaust gas probe (DEL_ERR). The first time period (TD1) is suitably set such that the corresponding difference between the end value (EW) and start value (STW) in case of filter failure (FIL_ERR) is the same as the end value in case of invalid time failure (DEL_ERR) The corresponding difference between (EW) and start value (STW) differs by the specified difference.

The invention relates to a stimuli-responsive nano material, which can be combined with an antigen generated by cryoablation to form a nano in-situ tumor vaccine, can realize the functions of lymph node targeting, in-vivo tumor fragment adsorption, targeted activation of antigen-presenting cells, pH-responsive drug controlled release, drug loading and the like, and provides a new method and a new technology for tumor immunotherapy. On the one hand, tumor fragments generated by cryoablation retain more antigen information, and an antigen presentation system can be activated more efficiently; and on the other hand, the stimuli-responsive nano material effectively adsorbs tumor fragments and can carry a pattern recognition receptor stimulant or drug, so that the ability of targeting and activating antigen-presenting cells is enhanced. According to the stimuli-responsive nano in-situ tumor vaccine prepared by the invention, tumor antigens generated by cryoablation are loaded, so that the defect that the cryoablation cannot kill far-end focuses and free tumor cells is overcome, and the stimuli-responsive nano in-situ tumor vaccine is expected to induce systemic immunotherapy while killing local focuses.

The invention relates to a process and the respective installation for thermal treatment of granular solids, in particular for producing aluminum oxide from aluminum hydroxide, wherein the solids areheated in at least one preheating stage and then reacted in a reactor at 700 to 1400 degree. In at least one preheating stage, the average temperature gradient of the solids amounts to <15K/s and thedwell time of the solids amounts to >=15 s.