131results about How to "Surge suppression" patented technology

A drive mechanism for delivery of infusion medium a coil capable of being electrically activated to provide an electromagnetic field. The coil surrounds a piston channel extending in an axial direction. The piston channel provides a passage for communication of infusion medium to an outlet chamber located at one end of the piston channel. An armature is located adjacent the coil, on one side of the axial channel. The armature is moveable toward a forward position, in response to the electromagnetic field produced by activation of the coil. A piston is located within the piston channel and is moveable axially within the channel to a forward position, in response to movement of the armature to its forward position. The armature and piston are moved toward a retracted position, when the coil is not energized. In the retracted position of the piston, a piston chamber is formed between the piston and a valve member and is filled with infusion medium. As the piston is moved to its forward position, the piston chamber volume is reduced and pressure within the piston chamber increases to a point where the pressure moves the valve member into an open position. When the valve member is in the open position, medium from the piston chamber is discharged into an outlet chamber located on the opposite side of the coil relative to the armature. An outlet is provided in flow communication with the outlet chamber, for discharging infusion medium from the outlet chamber.

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 invention discloses a ground automatic neutral-section passing device and a control method thereof. The ground automatic neutral-section passing device comprises a train identification unit, a logic control system, a valve control unit, a thyristor valve block unit consisting of two thyristor valve blocks connected in series, and a current detection unit for detecting the current of the thyristor valve blocks, which are connected successively, wherein the thyristor valve block unit is connected with a two-phase power supply arm and a neutral zone of a catenary respectively; the logic control system is connected to one of the thyristor valve blocks according to an identified train travelling position and direction control to supply power for the neutral zone; and when phase change is needed, the logic control system is connected to the other thyristor valve block according to the state switching of thyristor current. According to the control method, neutral-section passing is realized through controlling the two thyristor valve blocks, and when the phase change is performed, if the current of one of the thyristor valve blocks achieves a cross-zero state through detection and judgment, the other thyristor valve block is opened immediately. The ground automatic neutral-section passing device and the control method disclosed by the invention have the advantages of being capable of realizing automatic neutral-section passing of a train under a condition that the power is not cut off, high in reliability, stable in operation, extremely small in power-off dead zone of the neutral zone, and the like.

A light string includes series-connected groups of individual lights, with each light in each group being electrically in parallel with each other and with a parallel group device that regulates voltage within the group when one of the lights fails. In an alternating current circuit, the parallel group device is preferably two back-to-back zener diodes held in a partially on status so that, in the event one of the bulbs fails, it more quickly passes current in the reverse direction, thus preventing the remaining, operating lights from experiencing a current surge.

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 vehicular computer power supply and a surge voltage suppression method thereof. The vehicular computer power supply comprises a safety and reverse connection protection circuit, an input filter circuit, a high voltage surge suppression circuit, three boosted circuits, three DC / DC conversion circuits and an output filter circuit. The safety and reverse connection protection circuit is used for transmitting the first output voltage to the input filter circuit; the input filter circuit is used for transmitting the second output voltage to the high voltage surge suppression circuit; the high voltage surge suppression circuit is used for absorbing the high voltage surge of the second output voltage and outputting the third output voltage; the three boosted circuits are used for boosting the third output voltage during operation of low voltage surge and outputting three paths of fourth output voltage; the three DC / DC conversion circuits are used for isolating and converting the three paths of fourth output voltage into three paths of fifth output voltage; the output filter circuit is used for optimizing the three paths of fifth output voltage and outputs the sixth output voltage with low noise.

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 method for realizing serial port isolation and a serial port isolating circuit. The method comprises the following steps: converting RS232 level signals output by an RS232 level serial port into impulse signals by a first transformer module, converting the impulse signals into transistor-transistor logic (TTL) level signals, and then outputting the TTL level signals to a TTL level serial port; according to the received TTL level signals output by the TTL level serial port, selecting to output high-frequency signals to a second transformer module or third transformer module; converting the received high-frequency signals into RS232 negative level signals by the second transformer module, converting the received high-frequency signals into RS232 positive level signals by the third transformer module, and then outputting the RS232 positive level signals to the RS232 level serial port. The invention can effectively inhibit static electricity and surge, and preventan earth loop and surge from damaging a device serial port or interfering the normal operation of the device.

The invention relates to a PWM (pulse width modulation) based monostable vacuum circuit breaker permanent magnetic operating mechanism control method and a device for implementing the same. Adjustments are performed through three closed loops including a contact position loop, a contact speed loop and a mechanism coil current loop. Exciting current is adjusted by the contact position loop according to the contact position. A PWM duty cycle is adjusted by the contact speed loop according to feedback signals of the contact position loop. Switch-on-off operations are controlled by the mechanism coil current in real-time according to the exciting current and the PWM duty cycle. A fuzzy PID (proportional integral derivative) controller is adopted in the contact position loop and the contact speed loop. PI (priority interrupt) control is adopted in the mechanism coil current loop. The PWM based monostable vacuum circuit breaker permanent magnetic operating mechanism control method has the advantages that synchronous operation capacity and reliability of the mechanism are improved; the main coil current detection and the auxiliary contact travel detection are cooperated with each other; and a pulse width modulation technology is adopted in operations of a circuit breaker, closed-loop control of contact movement features in the switch-on-off operations of the circuit breaker is realized through changing the coil current, stability of operation time is guaranteed, and accuracy of switch-on-off phases is improved.

A first semiconductor element portion (SX) for switching a first current includes a first channel surface having a first plane orientation. A first region of a semiconductor layer includes a first trench having the first channel surface. A first gate insulating film covers the first channel surface with a first thickness. A second semiconductor element portion (SY) for switching a second current smaller than the first current includes a second channel surface having a second plane orientation different from the first plane orientation. A second region of the semiconductor layer includes a second trench having the second channel surface. A second gate insulating film covers the second channel surface with a second thickness larger than the first thickness.

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.

A high-withstand-voltage normally-on transistor (T1) and a low-withstand-voltage normally-off transistor (T1) are connected in series, and diodes (D1,D2) are provided in reverse parallel to the transistor (T2). A gate terminal of the transistor (T1) is connected to a source terminal of the transistor (T2), and a gate driving circuit (11) that outputs a control signal to a gate terminal of the transistor (T2) is provided. Forward voltage of the diode (D2) is made lower than forward voltage of the diode (D1), and an inductance component of a path connecting nodes (N1) (N3)via the diode (D1) is made greater than an inductance component of a path connecting the nodes (N2) (N3) via the diode (D1). Accordingly, a switching circuit which includes transistors connected in series and in which transient current at a time of turning off is reduced is provided.

The present invention discloses a medical power supply control circuit meeting EMC and safety standards. An isolation power supply employs a multi-level filter structure and is configured to filter out ultraharmonics in a power grid from the circuit through a ship-type switch, an isolated transformer and a surge protector in order and restrict a surge voltage possibly generated in a thunder and lightning condition in a range which can be accepted by a device and a system. Usage of the isolation transformer ensures safety of operators. A solid-state relay controls power supply input of a driver, and the input end of the driver is provided with an EMI filter and a 10MH reactor, so that motor interference generated between the driver and peripheral devices is reduced, and the driver has a good electromagnetic compatibility. The driver outputs SPWM modulated waves and filters the SPWM modulated waves to approximate sine waves through a sine filter, and finally the approximate sine waves access the motor. The power supply control circuit meets the medical EMC and safety standards can pass GB9706.1-2007 standard and YY0505-2012 standard and detection and national related product standards.

Provided is a switching power supply device capable of effectively improving power supply efficiency with a small number of parts. The switching power supply device includes: a switching circuits (S1 to S4) for converting DC input power into AC power, a transformer (T) having a primary winding to which the AC power is supplied, first rectifiers (D21, D22) for rectifying the AC power induced by the secondary winding of the transformer into DC power, second rectifiers (D31, D32) having anodes connected to cathodes of the first rectifiers, and a capacitor (C) connected between the cathodes of second rectifiers and a predetermined potential node and functioning as an auxiliary power source of a predetermined load (F). Surge generated at the cathodes of the first rectifiers (D21, D22) of the secondary side during switching is supplied to the capacitor (C) via the second rectifiers (D31, D32). The load (F) uses power charged in the capacitor as an operation power source.

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.

A surge suppressor for protecting electronic equipment by suppressing damaging surges of low frequency signals in a radio frequency (RF) transmission line, while allowing RF signals of a desired frequency range to pass through the transmission line. The surge suppressor can comprise a housing, a center pin connected to a stub, and at least one interface pin conductively coupled to the cable and capacitively coupled to the center pin. The surge suppressor can have a signal pass through bandwidth approximately 10 times exceeding the bandwidth of traditional quarter wavelength stub (QWS) devices, a higher return loss, and higher surge attenuation level. The surge suppressor can be symmetrically insertable into a cable providing an RF communication line.

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.

A surge suppressor for protecting electronic equipment by suppressing damaging surges of low frequency signals in a radio frequency (RF) transmission line, while allowing RF signals of a desired frequency range to pass through the transmission line. The surge suppressor can comprise a housing, a center pin connected to a stub, and at least one interface pin conductively coupled to the cable and capacitively coupled to the center pin. The surge suppressor can have a signal pass through bandwidth approximately 10 times exceeding the bandwidth of traditional quarter wavelength stub (QWS) devices, a higher return loss, and higher surge attenuation level. The surge suppressor can be symmetrically insertable into a cable providing an RF communication line.

The invention discloses a transformer inrush current suppression method, device and equipment. Based on the three-phase split-phase premagnetization and split-phase phase-controlled closing of a transformer, the winding flux of each phase is charged to the saturation flux one by one, and then, closing is carried out one by one, so that the inrush flow of each phase is effectively suppressed, and excitation inrush current is hardly generated in the whole process; and the residual magnetism of an iron core does not need to be known, and thus the technical problems that the existing transformer inrush current suppression method needs to depend on the known residual magnetism of the transformer, and the excitation inrush current of each phase cannot be effectively suppressed under the condition that the residual magnetism of the transformer is unknown are solved.

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 valve spring device is provided with a first coil spring and a second coil spring combined in series with each other. The inside diameter (coil inside diameter) of the second coil spring is greater than the outside diameter (coil outside diameter) of the first coil spring. A part of the first coil spring including an end portion along an axis is inserted into the second coil spring, thereby forming a combined spring. The end portion of the first coil spring and an end portion of the second coil spring are connected to each other by a connecting member. The first and second coil springs are compressed along the axis as they are located in series between a cylinder head and a retainer. A shaft of a valve is passed within the coil springs.