13results about How to "Surge suppression" patented technology

The utility model discloses a surge suppression device for a centrifugal fan. The surge suppression device is connected to a variable-frequency magnetic suspension centrifugal blower and a shaft furnace. An air outlet of the variable-frequency magnetic suspension centrifugal blower is communicated with an air inlet pipeline of the shaft furnace; comprising an electric control valve, a bypass pipe, an air volume detector and a display, a bypass pipe is arranged on a pipeline for communicating the air outlet of the variable-frequency magnetic suspension centrifugal blower with the air inlet of the shaft furnace; an electric control valve is arranged on the bypass pipe; the electric control valve is arranged on the bypass pipe; the air volume detector is arranged at an air inlet of the variable-frequency magnetic suspension centrifugal blower; the air volume detector is electrically connected with the displayer. The device combines the characteristic of high-rotating-speed operation of the magnetic suspension fan, and can effectively avoid the surge phenomenon at the low-firepower preheating stage of the shaft furnace under the conditions that the pipe network resistance is not increased and the fan maintains the existing constant-pressure variable-frequency control mode.

The present invention relates to an inductive phase-controlled device and surge suppression equipment for capacitor combination gate surge control of power supply and distribution circuit devices. The phase-controlled device includes a cylindrical shell, a silicon stack, an energy absorption component, an auxiliary module and a wiring harness, and the silicon stack, the energy absorption component, the auxiliary module and the wiring harness are all installed in the cylindrical shell. The phase-controlled device in the capacitor combination gate surge suppression equipment is provided with a CT power supply module, a heat dissipation module, an air duct and a wiring hub, so that the phase-controlled device can respond quickly according to the current increased when surge current and overvoltage occur, actively cool down, and reduce the time the phase-controlled device is in a high temperature state, thereby delaying the aging of the phase-controlled device and the process of insulation performance degradation, which has a positive effect on extending the service life of the phase-controlled device.

The application discloses a method, medium and system for determining the closing speed of a phase-selected vacuum switch for closing a capacitive load, comprising: repeatedly performing multiple closing experiments on the fast vacuum switch at different closing speeds and at different closing phases under a power frequency voltage; collecting the minimum pre-breakdown voltage and the power frequency voltage corresponding to the closing process of each closing speed; drawing the curve of the minimum pre-breakdown voltage corresponding to each closing speed of the fast vacuum switch changing with time and the curve of the power frequency voltage changing with time; if the closing process corresponding to at least one closing speed meets a first preset requirement, selecting the smallest closing speed as the lower limit of the closing speed of the fast vacuum switch; and the first preset requirement is that the slope of the curve of the minimum pre-breakdown voltage changing with time is greater than the slope of the curve of the power frequency voltage changing with time at the same time. The application determines the minimum closing speed, and reduces the pre-breakdown high-frequency inrush current in the process of closing the capacitive load by the vacuum switch.

This invention discloses an energy-saving ammonium chloride evaporation crystallization system and process. The system includes a feed preheating unit, a first-effect falling film evaporation unit, a second-effect falling film evaporation unit, and a forced circulation evaporation crystallization unit connected sequentially along the feed liquid flow direction. It also includes a falling film scrubbing tower, a forced circulation scrubbing tower, and a three-stage compressor. The forced circulation secondary steam, after scrubbing, enters the first-stage compressor. The second-effect secondary steam, after scrubbing, bypasses the first-stage compressor and merges at the outlet side of the first-stage compressor. It is then compressed in the second and third stages and reused for the first-effect falling film evaporation and forced circulation evaporation crystallization. This process, by setting the falling film evaporation to double-effect, only compresses the second-effect and forced circulation secondary steam; by using the first-stage compressor to separately increase the temperature rise of the forced circulation secondary steam, compensating for its high boiling point rise, it merges with the second-effect steam and is then compressed in the second and third stages for reuse. Since the boiling point rise in the falling film section is low, the second-effect steam only requires two stages of compression to meet the heat transfer temperature difference. This effectively reduces the amount of gas passing through and power consumption, and improves stability.

The present invention relates to a large-scale power transformer excitation system and method for a circuit system for power supply and distribution. The excitation system includes an excitation system transformer, a low-voltage side switch and an excitation surge current suppression device, and the excitation surge current suppression device includes a phase-controlled main circuit, a bidirectional current suppression module and an inrush current control unit. The excitation surge current suppression device allows the transformers running in parallel to serve as power sources for each other as backup, thereby ensuring the stability and reliability of the power grid system and reducing the negative impact on the electricity consumption of residents covered by the power grid system. In particular, for enterprises that rely on high-quality power supply, the stability and power supply reliability of the power grid system ensure the electricity demand of the enterprise's production and reduce production losses caused by power outages.

The application relates to the technical field of underwater power supply, and provides a surge protection circuit and an underwater medium-voltage conversion power supply, which comprise a protection subcircuit and a reset subcircuit arranged in parallel. The protection subcircuit is arranged between a power supply end and a subsequent circuit, and the protection subcircuit is connected in parallel with the subsequent circuit. The protection subcircuit comprises at least one protection device, which is used for turning on the protection subcircuit to short-circuit the subsequent circuit when the change rate of input voltage of the power supply end is greater than a preset threshold value and the input voltage is greater than a first breakdown voltage. The reset subcircuit is arranged between the protection subcircuit and the subsequent circuit, and is used for closing the circuit to reset the protection subcircuit after the protection subcircuit is turned on. Based on the scheme provided in the embodiment, the protection subcircuit is rapidly turned on when a transient high-voltage impact is detected, the surge current is discharged, the reset subcircuit automatically cuts off the protection path after the surge ends, the normal power supply of the system is restored, and the operation reliability and self-recovery ability of the medium-voltage conversion power supply in a complex marine environment are improved.

The invention discloses an air supply device and method for a cathode closed electric pile or a methanol fuel cell. The device comprises a high-speed brushless direct current motor, a centrifugal impeller directly driven by the high-speed brushless direct current motor, a volute for packaging the impeller and an electronic control unit. The impeller and the volute are pneumatically optimized, so that the device has high efficiency and a wide stable working area under the back pressure of 1-10kPa. The electronic control unit takes the load current of the electric pile as a main feed-forward signal, quickly sets the target rotating speed of the motor through a built-in mapping table, and realizes accurate tracking by adopting a rotating speed closed loop. The control unit is integrated with mechanisms such as self-learning compensation, anti-disturbance quick response, safety protection and anti-integral saturation. According to the invention, the harsh requirements of a miniaturized fuel cell system on high back pressure, fast response, small size and long service life of an air supply component are met.

The present application relates to a silicon carbide power component, a driving circuit and a control method. A silicon carbide power component is controlled by a driver and has a gate-to-source voltage and a source voltage, wherein the source voltage decreases according to the increase of the gate-to-source voltage, or the source voltage increases according to the decrease of the gate-to-source voltage, thereby suppressing a surge generated by the change of the gate-to-source voltage, thereby suppressing the crosstalk phenomenon of the silicon carbide power component.

The embodiment of the application discloses a control method and device of a fuel cell turbo-compressor. The method comprises the following steps: identifying a current working condition according to an operating parameter; in a slow load reduction working condition, slowly opening a bypass valve, slowly closing a variable nozzle ring, reducing a high-speed drive motor speed and a throttle opening degree, maintaining a compressor outlet flow rate not lower than a minimum safe flow rate, recovering turbine residual pressure energy and motor rotor kinetic energy; in a rapid load reduction working condition, quickly opening the bypass valve, quickly closing the variable nozzle ring, reducing the high-speed drive motor speed and the throttle opening degree, maintaining the compressor outlet flow rate not lower than the minimum safe flow rate, recovering the turbine residual pressure energy and the motor rotor kinetic energy; in an emergency shutdown working condition, fully closing the variable nozzle ring, fully opening the bypass valve, idling the high-speed drive motor, keeping the throttle at a purge opening degree and stopping the system after the purge is completed, so that on-line surge suppression, pressure overshoot control and energy recovery are coordinated, and the system safety and energy utilization rate are improved.

The invention relates to a cooperative control method for parallel multi-break electromagnetic switches. The method comprises the following steps: designing a single-pole electromagnetic switch intelligent control module, and realizing signal transmission when each pole switch is switched on and switched off through an associated control module. Through a fixed-phase switching-on control strategy, load properties are detected in real time, and corresponding control strategies are formulated for switching-on inrush currents with different characteristics caused by different load properties so as to reduce contact ablation caused by bouncing arcs during switching-on. In order to improve the breaking capacity of the parallel multi-break electromagnetic switch, a cooperative breaking control strategy is adopted to improve the consistency of the opening moment.

The utility model discloses a solid-state constant-current extensible high-power soft starting device and an extension device thereof. The soft starting device comprises a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, a triode V2, a diode D1, an NMOSFET tube Q1, a first capacitor C1, a second capacitor C2 and a plurality of charging capacitors. Wherein the first resistor R1 and the second resistor R2 are connected in series between the positive electrode and the negative electrode of a power supply, the connection point of the two is connected with the collector of the triode V2 through the first capacitor C1 and the third resistor R3 which are connected in parallel, and the emitter is connected with the negative electrode of the power supply through the diode D1; the connection point is further connected with the grid electrode of the NMOSFET Q1, the source electrode of the NMOSFET Q1 is connected with the base electrode of the triode V2 and connected with the negative electrode of the power supply through the fourth resistor R4, the second capacitor C2 is located between the grid electrode and the negative electrode of the power supply, and the charging capacitors are connected between the positive electrode and the drain electrode of the power supply in parallel. According to the utility model, the surge during startup can be suppressed, and the surge generated when the load power is greatly changed can be suppressed in real time.

The invention relates to an inductive phase control device for capacitor combination gate inrush current treatment of a power supply and distribution circuit device and inrush current suppression equipment. The phase control device comprises a barrel shell, a silicon stack, an energy absorption assembly, an auxiliary module and a wire harness, and the silicon stack, the energy absorption assembly, the auxiliary module and the wire harness are all installed in the barrel shell. The phase control device in the capacitor combination gate inrush current suppression equipment is internally provided with a CT power taking module, a heat dissipation module, an air duct and a line concentration bolt, so that the phase control device can quickly respond according to the inrush current and the current rising when overvoltage occurs, cooling is actively carried out, the duration of the phase control device in a high-temperature state is shortened, and the service life of the phase control device is prolonged. Therefore, the aging of the phase control device and the reduction of the insulating property are delayed, and the positive effect on prolonging the service life of the phase control device is achieved.

The utility model belongs to the field of circuit design, and particularly relates to a surge suppression circuit, which comprises an N line, an L line and a first surge module, the first surge module comprises a first winding resistor, a second winding resistor, a first piezoresistor, a second piezoresistor, a third piezoresistor and a first capacitor; the first end and the second end of the first piezoresistor are electrically connected with the first end of the first winding resistor and the second end of the second winding resistor respectively, and the first end and the second end of the second piezoresistor are electrically connected with the first end of the second winding resistor and the second end of the first winding resistor respectively. And the third piezoresistor and the first end and the second end of the first capacitor are electrically connected with the second end of the first winding resistor and the second end of the second winding resistor respectively. According to the utility model, when a surge enters an N line or an L line, the surge can be effectively inhibited and the circuit can be effectively protected based on the cross design of the winding resistor and the piezoresistor in the first surge module.