125results about How to "Surge suppression" patented technology

An internal baffle apparatus for use within tanks, in particular flexible tanks, for liquids for dampening surges of liquid, and tanks having such baffle apparatus, wherein the baffle apparatus comprising a plurality of panel members connected along a connection line that defines an axis wherein said panel members extend radially from the axis such that each panel member is oriented in a radial plane, and each panel member having a bottom edge, a top edge portion and a remote edge opposite the axis, wherein the bottom edge of each panel includes first connector means operable for connecting the bottom edge at a plurality of connection points to the bottom wall of the tank, and the top edge portion includes second connector means located remote from the axis that are operable to connect the top edge portion to an upper part of the tank.

The present disclosure relates to a multiple-capacity centrifugal compressor, which includes a plurality of capacity-control mechanisms. Each of the capacity-control mechanisms includes an inlet guide vane and an outlet diffuser, so that the multiple-capacity centrifugal compressor provides a flexible control strategy. In addition, the present disclosure further provides a method for controlling the multiple-capacity centrifugal compressor that effectively adjusts and controls the capacity-control mechanisms by coarsely adjusting the inlet guide vanes and combined with subsequently adjusting the outlet diffusers.

The invention discloses a segmented resistance type IGBT driving circuit, which is characterized in that a segmented resistor driving circuit comprises a plurality of segmented resistors which are connected in series, both ends of each segmented resistors are connected with a bypass MOS transistor in parallel; each bypass MOS transistor and a driving push-pull circuit are connected with a driving controller; and an IGBT gate clamping circuit comprises an IGBT gate voltage-stabilized clamping circuit and an IGBT gate power supply clamping circuit. The invention further discloses a control method of the segmented resistance type IGBT driving circuit, which is characterized in that a pulse rising edge and a falling edge are driven at the gate, and the size of the gate driving resistance is changed through switching of the bypass MOS transistors. The segmented resistance type IGBT driving circuit and the control method thereof can achieve the purposes of reducing the switching loss of an IGBT device and improving the application frequency of the device while ensuring suppression for surge and gate oscillation.

The invention discloses a system for preventing reverse recovered charges in a DUT. The system is a current injection circuit connected to the two ends of the DUT in a forward bias mode. The injected current circuit comprises a pulse nS-level pulse signal generator formed by an SRD and a pulse edge acceleration circuit formed by a BG2 and a BG1, wherein the pulse edge acceleration circuit is tightly connected with the back of the pulse nS-level pulse signal generator and used for shortening the rising edge time and the falling edge time of pulses. The system has the advantages that the reverse recovered features of the DUT can be improved, the reverse recovered charges can be reduced, and the reverse recovered time can be shortened; meanwhile, switching losses and conduction losses of the DUT can be reduced, electromagnetic interference and surges can be restrained, and efficiency is improved.

The invention provides a power supply charging control circuit and a power supply charging control method. The power supply charging control circuit is characterized in that an AC (Alternating Current) power supply outputs a direct current through a rectification module to charge an electrolytic capacitor, so as to form a charging loop, a plurality of current limiting modules are connected in parallel and then connected to the charging loop in series, when the power supply charging control circuit is powered up, one or several current limiting modules in the plurality of current limiting modules are controlled to be conducted at different time by an MCU (Microprogrammed Control Unit), so as to charge the electrolytic capacitor. Through adoption of the power supply charging control circuitof the invention, one or several current limiting modules in the plurality of current limiting modules are controlled to be conducted at different time, so that resistances of current limiting resistors in the charging loop are different when charging is performed at different time, in addition, the resistance of the current limiting resistor which is charged firstly is large so as to suppress surge, and the resistance of the current limiting resistor which is charged later is small so as to accelerate a charging speed, in comparison with a conventional charging circuit with a single current limiting resistor or without current limiting resistor, the power supply charging control circuit of the invention accelerates the charging speed while suppressing a large surge charging current, thereby improving operation stability of the whole circuit device.

The invention relates to a centrifugal compressor using an asymmetrical bladed diffuser with variable blade consistencies in the circumferential direction, and belongs to the technical field of turbomachinery. The centrifugal compressor comprises a volute, a centrifugal impeller and the bladed diffuser. The inlet front edge positions and the bladed mounting angles are evenly distributed in the circumferential direction, the blade consistencies are asymmetrically distributed in the circumferential direction, and the consistencies are unequal in different circumferential positions. The blade consistencies are changed by changing the central angles (namely the front edge interval between every two adjacent blades) corresponding to flow channels. The compressor can effectively adapt to the downstream circumferential pressure distortion of the bladed diffuser, the nonuniformity of a flow field in the bladed diffuser is reduced, the flowing stability of the centrifugal compressor is effectively improved, and the stable working range of the centrifugal compressor is enlarged.

The present invention is a currency-operated liquid dispensing machine for liquid retained in a plurality of removable and replaceable containers such as carboys or bags. More specifically, it is for a vending machine for dispensing metered quantities of water.

A centrifugal compressor includes a housing that accommodates a wheel. The housing includes an air intake space formed on an entrance side of the wheel; a flow passage to guide fluid compressed by the wheel to the outside of the housing; a return flow passage opened on each wall surface of the air intake space and the flow passage to circulate a part of the fluid in the flow passage to the air intake space without passing through the wheel; and an introduction portion provided in the air intake space, and having an inner peripheral surface that forms a flow passage to guide the fluid from the outside of the housing to the wheel. A downstream end of the inner peripheral surface in a flowing direction of the fluid is located inside in the radial direction of a shaft than the wall surface of the housing.

The invention discloses a DCDC power supply protection circuit of an electric automobile. The DCDC power supply protection circuit comprises a diode, a resistor, a capacitor, a relay and a control circuit. The diode is connected with the resistor in series. The two ends of the serial-connection circuit of the diode and the resistor are connected with the input end of a power circuit and the output end of a power supply respectively. The serial-connection circuit of the diode and the resistor is connected with the relay in parallel. The two ends of the relay are connected with the input end of the power circuit and the output end of the power supply respectively. The capacitor is connected with the input end of the power circuit in parallel and connected with the serial-connection circuit of the diode and the resistor. The control circuit is connected with the control end of the power circuit and the control end of the relay. The control circuit samples the voltage of the capacitor and controls the relay to be switched on and switched off according to an external instruction and the sampling result.

The present invention provides a DC overvoltage protection circuit, including a voltage limiting circuit mounted on the circuit board of the case, characterized in that the voltage input end is electrically connected with a variable impedance electronic switch, an overvoltage detecting circuit and a ripple detecting circuit respectively, the overvoltage detecting circuit and the ripple detecting circuit are electrically connected to the input end of the variable impedance electronic switch, the output end of the variable impedance electronic switch is electrically connected to the spike snubber circuit, output voltage by the voltage output end. The invention is used as an attaching device which is serial connected on the front of the product using electricity, capable of preventing spike and surge, the circuit has lower voltage drop at the same time, the circuit is general, fir for product having larger power and smaller power, having widely application. The invention adopts unit having smaller volume adding the upper limit of the working voltage of the present product, greatly improving the power supplying compatible ability and the credibility of the electrical appliance compared with the traditional spike, surge preventing circuit.

The invention provides a surge protector which comprises a machine seat capable of being fixed on a guide rail and a pluggable module capable of being inserted into the machine seat, wherein the pluggable module comprises a cover-shaped module shell, a first printed circuit board, a second printed circuit board and a module bottom cover, wherein the first printed circuit board and the second printed circuit board are relatively arranged in the module shell in parallel, a necessary current leakage distance and an air distance are formed between the first printed circuit board and the second printed circuit board, and the first printed circuit board and the second printed circuit board are respectively provided with claw pieces used for being connected with rows of wiring terminals; the module bottom cover is inserted into the bottom end of the module shell, is provided with positioning grooves used for fixing the first printed circuit board and the second printed circuit board and allowing the claw pieces to extend out; the machine seat comprises a machine seat shell and a grounding contact, wherein through grooves for allowing the claw pieces to pass through are formed in the top of the machine seat shell, and a connecting module connected with the claw pieces is arranged inside the machine seat shell; the grounding contact is inserted into the bottom end of the machine seat shell to fix the machine seat shell and the guide rail; the grounding contact comprises grounding metals connected with the claw pieces in the first printed circuit board and the second printed circuit board. The surge protector provided by the invention can be used for restraining surge on a line in the structure of rows of wiring terminals.

The invention belongs to an intelligent three-phase electricity-saving protection controller which comprises a three-phase firewire, a zero line input terminal and an earth wire input terminal, wherein the three-phase firewire and the earth wire input terminal are connected with an input end of a transient surge suppression unit; an output end of the transient surge suppression unit and the zero line input terminal are connected with an input end of a voltage adjusting three-phase balancing unit, an output end of the voltage adjusting three-phase balancing unit is connected with an input end of a harmonic compensation unit, and an output end of the harmonic compensation unit is connected with a load. The intelligent three-phase electricity-saving protection controller integrates the advantages of a system type, a filtering compensation type, a voltage adjusting type and an electromagnetic type electricity-saving protection devices, so as to have good comprehensive treatment effect, reduce the electricity-saving cost, avoid installation and debugging for a plurality of electricity-saving devices in the installing process, save manpower, physical resources, financial resources and time consumption, and be suitable for a power system and electric equipment with multiple voltage classes.

A diaphragm (4) covers an impeller (3) so as to be capable of rotating about an axis line (O). Formed in the diaphragm (4) are an intake flow channel (FC1) for supplying a gas (G) to an inlet of the impeller (3), a diffuser flow channel (FC4) through which gas (G) flows that has been discharged radially outward from the impeller (3), and a communication part (24) for constantly communicating the intake flow channel (FC1) and the diffuser flow channel (FC4).

In an exhaust blowing fan, if surging occurs, the changing and vibration of the pressure generate, and the changing and the vibration as well as sound syntonizing with the sound of blades together generate noise (sound pressure level) and lead blow-in capability to decline. Therefore, the invention aims to provide an exhaust blowing fan which inhibits the cause of surging as possible namely generation of swirling flow. The exhaust blowing fan comprises an impeller consisting of a shaft hub and a plurality of blades arranged around the shaft hub, a motor used to rotate the impeller rotate, and a motor shell which receives the impeller and the motor and is approximately of a cylindrical shape, wherein the shell is formed by connecting a tube expanding cylinder part with large diameter and a main tube cylinder part with small diameter through a reducing tube cylinder part with gradually-reducing diameter. In addition, The middle position of the axial height of the blades is set at a place where the dividing line of the reducing tube cylinder part and the main tube cylinder part is at distance which is less than 20 percent of the height of the axis of the blades from the axis of the blades forward and backward respectively.

The invention discloses a transformer pre-magnetizing device and a pre-magnetizing method of the transformer pre-magnetizing device. The transformer pre-magnetizing device comprises an intelligent main open circuit device, a transformer input end switch device, a pre-magnetizing switch device, a pre-magnetizing slide rheostat and a control circuit. One end of the intelligent main open circuit device is connected with a main input circuit, the other end of the intelligent main open circuit device is connected with one end of the pre-magnetizing switch device and one end of the transformer input end switch device, the other end of the pre-magnetizing switch device is connected with one end of the pre-magnetizing slide rheostat, the other end of the transformer input end switch device and the other end of the pre-magnetizing slide rheostat are connected with a primary side of a transformer, and the control circuit controls the switching motions of the transformer input end switch device and the pre-magnetizing switch device. The invention further discloses the pre-magnetizing method with the transformer pre-magnetizing device adopted. The transformer pre-magnetizing device can limit an excitation surge current when the large-sized transformer is applied to a small-capacity power grid in a power supply system, so that the transformer and the power grid are protected.

A correction unit calculates a correction amount so that sine waves of the respective phases are coincident with one another and changes a PWM signal for carrying out the PWM control on switching elements e.g. metal oxide semiconductor field effect transistors (MOSFETs) based on the computed correction amount. A storage unit is adapted to store the correction amount for each phase based on the detection result. The switching elements are subjected to pulse width modulation (PWM) control to generate sine waves of multiple phases. A motor (5) includes a stator coil that produces rotational magnetic field upon receiving sine waves, and a rotor that is driven by the action of the rotational magnetic field.

A semiconductor module is provided with three-phase upper arms (51, 53, 55) and lower arms (52, 54, 56), heat-dissipating plates (11, 12), a main circuit-side bus bar, an output terminal-side bus bar, a control terminal (14), and a resin mold part (18). The output terminal-side bus bar has U-phase to W-phase wiring layers (133-135) layered and arranged facing each other interposed by an insulating layer (130), and U-W terminals (13c-13e) for electrically connecting each of the U-phase to W-phase wiring layers and a load. There are an even number of U-phase to W-phase wiring layers.