33results about How to "Improve pressure regulation performance" patented technology

The invention relates to a coordinated control method for multistage reactive voltage in an active distribution network. The control method comprises the steps of grading voltage regulation resources in the active distribution network, executing four stages of voltage regulation in sequence from low to high, judging whether the voltage level of the whole network is qualified after each stage of voltage regulation, and when the voltage level of the whole network is qualified, not performing next stage of voltage regulation, wherein the four stages of voltage regulation are respectively first, second, third and fourth ones of a power system realized by using a distributed photovoltaic power supply, reactive power output of a photovoltaic power station, a traditional VQC (Voltage Quality Control) device and active power output of the photovoltaic power station. Compared with the prior art, the control method sufficiently using the scattered voltage regulation resources in the active distribution network has the advantages of effectively reducing the actions of the VQC device, improving the voltage level of the distribution network and the like.

The invention discloses a light-load control method for energy feedback of a Buck-Boost LLC two-stage converter, and belongs to the technical field of power generation, power transformation or power distribution. In each light-load working cycle, the microcontroller configures the timer to enter the energy feedback control mode, and generates a set of switching signals of the primary and secondary sides with a phase difference, and then drives the switching tubes of the primary side and the switching tubes of the secondary side respectively. The rectifier tube reverses the terminal voltage on the secondary side, and realizes that the energy of the load passes through the resonant circuit and then transfers back to the source, thereby reducing the output voltage. After entering the energy feedback control mode, part of the energy will be fed back to the primary side every cycle. By adding phase adjustment, the invention solves the problem of excess output energy under the light load state, ensures the stability of the output voltage, and improves the voltage regulation capability of the two-stage converter under the light load state.

The invention relates to a series-parallel connection comprehensive compensation device for power distribution network low-voltage treatment. The series-parallel connection comprehensive compensation device comprises a series connection compensating module, a parallel connection compensating module, and a controller. The series connection compensating module is disposed in a main loop circuit and is connected with a rapid vacuum switch in the main loop circuit. The parallel connection compensating module is connected with the main loop circuit through a vacuum contactor. The controller is connected with the rapid vacuum switch and the vacuum contactor and is used for controlling the operation of the series connection compensating module and the parallel connection compensating module via the rapid vacuum switch and the vacuum contactor according to the voltage and the load at the tail end of a power distribution network system. Compared with a product in the prior art, the series-parallel connection comprehensive compensation device is simultaneously provided with the series connection compensating module and the parallel connection compensating module, comprehensively controls a series capacitor loop circuit and a parallel capacitor loop circuit according to a system requirement, may change circuit reactance and system reactive power flow, and may absorb harmonic waves so as to greatly enhance the voltage regulating capability and range of a device.

The invention provides a transformer on-load capacity-regulating voltage-regulating tap changer comprising a T-shaped support. The T-shaped support is composed of a horizontal part and a vertical part. An on-load regulation mechanism and an on-load voltage-regulating spindle barrel are disposed on two sides of a support plate of the horizontal part respectively. Two motors are disposed on the on-load regulation mechanism side of the support plate. An on-load capacity-regulating contact system of the tap changer comprises a capacity-regulating fixed contact, a capacity-regulating transition resistor and a capacity-regulating moving contact. An on-load voltage-regulating contact system of the tap changer comprises a voltage-regulating fixed contact, a voltage-regulating transition resistor and a voltage-regulating moving contact. Compared with the prior art, the transformer on-load capacity-regulating voltage-regulating tap changer is small in size and meets the requirement for large-range voltage regulation for 3-9 tap positions.

The invention discloses a tank typed large flow pressure adjuster suitable for a low pressure drip irrigation system belonging to the technical field of agricultural water-saving irrigation. The technical proposal includes a tank typed shell, a water inlet and a water outlet respectively arranged on a front side wall and a back side wall of the shell. The invention is characterized in that the shell is provided with a lifting frame with a floating ball floating up and down, wherein, the lifting frame includes an upstream baffle and a downstream baffle respectively near the front inner wall and back inner wall of the shell, and the upstream baffle and the downstream baffle are respectively provided with a water inlet through opening and a water outlet through opening corresponding to the water inlet and the water outlet. The invention has the advantages of good pressure adjusting performance, convenient installation and use, equal starting regulation pressure and outlet pressure (the outlet pressure is designed by the height of a water level in a water tank), simple structure, convenient manufacture, low cost, convenient maintenance, etc.

The present invention provides a fuel pressure adjusting device, capable of implementing small-diameter resinification of fuel piping without a design problem of laying the fuel piping, and reducing cost. The fuel pressure adjusting device (40) is arranged on a fuel piping (30) for supplying fuel compressed by a fuel pump (29) to a fuel injection device (26), wherein at least a part of the fuel piping (30) is telescopic in a fuel passage direction or in a direction that is vertical to the fuel passage direction, so as to increase or decrease a volume of the fuel passage in the telescopic part to restrain the pressure of the fuel piping (30) from fluctuation.

The invention proposes an ultra-wide gain range adjustment method for L-LLC resonant converters, which is suitable for flexible DC transmission and distribution networks, new energy grid connection, battery energy storage, etc. field. The method for adjusting the ultra-wide gain range of the L-LLC resonant converter proposed by the present invention endows the L-LLC resonant converter with a wide range of voltage regulation capabilities and ensures the good soft switching characteristics of the L-LLC resonant converter. The L‑LLC ultra-wide gain range adjustment method optimizes the bridge arm control and eliminates the bias phenomenon introduced by the auxiliary inductance.