33results about How to "Improve the quality of supply voltage" patented technology

The invention relates to a new-type urbanization-based low voltage treatment measures optimization method, which comprises the steps as follows: system parameters of a power distribution network are obtained; the maximum load as shown in the specification of a distribution transformer is calculated according to the distribution transformer capacity; eta represents the load rate of the distribution transformer; S represents the capacity of the distribution transformer; rhi represents a power factor; the current power load of a load terminal is counted; the reason of a low voltage is judged according to the system parameters, and the power load, namely the maximum load of the distribution transformer; if the current power load is greater than the maximum load P of the distribution transformer, voltage adjustment is carried out through a power distribution device; and if the current power load is smaller than the maximum load P of the distribution transformer and when terminal voltage fluctuation of a to-be-tested circuit is greater than a standard value, voltage adjustment is carried out through a wire with a relatively large wire diameter. The terminal voltage of an urban power grid is improved; the reactive current flow of the circuit is reduced; the electric energy loss is reduced; and the quality of a power supply voltage of a rural power grid is improved.

The invention discloses a novel electric system reactive power compensation system. The novel electric system reactive power compensation system comprises a sampling detection circuit, an intelligent terminal, a compensation controller, a switching control circuit and a reactive compensation unit. The input end of the sampling detection circuit is connected with a three-phase power grid. The output end of the sampling detection circuit is connected with an intelligent terminal. The intelligent terminal is connected with the compensation controller. The compensation controller is connected with the switching control circuit. The switching control circuit is connected with the reactive compensation unit. According to current sampling detection in a sampling detection circuit power grid, the switching control circuit is controlled according to a detection result, a capacitor is switched on or switched off according to certain rules, reactive compensation is performed on the three-phase power grid, automatic real-time compensation for reactive power is achieved, the power supply voltage quality is improved, and the problem that due to the fact that other two-phase under-compensation or over-compensation is caused by existing current single-phase sampling detection, voltage fluctuations of rear-end electric consumption are caused is solved.

The invention provides reactive power series compensation device topological wiring used for a high-voltage and medium-voltage distribution network. The reactive power series compensation device topological wiring comprises a compensation capacitor Cap, a metal oxide voltage dependent resistor FR, a rapid discharge switch KF1 and a rapid bypass switch KF2. The compensation capacitor Cap is connected in series on a power supply line. The metal oxide voltage dependent resistor FR and the compensation capacitor Cap are connected in parallel. The rapid discharge switch KF1 and the rapid bypass switch KF2 are respectively connected in parallel with the compensation capacitor Cap. The beneficial effects are that operation overvoltage and discharge surge of the line can be solved from the perspective of the wiring and the principle, the problems of reducing the rated voltage of a series compensation capacitor and protecting safe operation of a capacitor bank can be effectively solved, real-time operation electrical parameters can be monitored and the wiring has the function of preventing failure of operation of the rapid switch so that construction cost of the series compensation device is enabled to be greatly reduced, the size is reduced, installation sites are flexible and equipment maintenance is simple.

Wherein, with PWM but not coupled transformer to couple or isolate the ac or dc, it compensates the ac voltage in series directly, can stabilize voltage and filter to the ac power supply in electrical distribution system, and improves power supply quality, even there is frequency fluctuation. This invention has small volume and high efficiency with low cost.

The invention discloses an on-load capacity-regulating voltage-regulating transformer comprising an oil tank, an iron core, an on-load capacity-regulating voltage-regulating switch and a winding coil;the oil tank is a corrugated oil tank; the iron core is an amorphous alloy iron core; the winding coil is a three-phase three-winding coil which consists of a low-voltage serial-parallel connection layer, a low-voltage serial connection basic layer and a high voltage layer; the low-voltage serial-parallel connection layer, the low-voltage serial connection basic layer and the high voltage layer are sequentially concentrically sleeved on the amorphous alloy iron core; the on-load capacity-regulating voltage-regulating switch is arranged above the amorphous alloy iron core; a high voltage sleeve, a low voltage sleeve and a zero-phase sleeve are arranged on the corrugated oil tank; the high voltage layer is connected with the high voltage sleeve via the on-load capacity-regulating voltage-regulating switch; the low-voltage serial-parallel connection layer and the low-voltage serial connection basic layer are connected with the low voltage sleeve via the on-load capacity-regulating voltage-regulating switch; the low-voltage serial-parallel connection layer is also connected with the zero-phase sleeve; the three-phase three-winding coil, the amorphous alloy iron core and the on-load capacity-regulating voltage-regulating switch are all placed in the corrugated oil tank.

An embodiment of the invention provides an inter-line multifunctional fault current limiting system. The system is characterized in that a first switch tube and a first supercapacitor are connected between one end and the other end of a first dynamic voltage compensation module in series; one end of the first dynamic voltage compensation module is connected to one end of a first switch; the otherend of the first switch is connected to one end of a current-limiting inductor; the other end of the current-limiting inductor is connected to the other end of the first dynamic voltage compensation module; one end of an energy-discharging resistor is connected to the other end of the first switch while the other end of the energy-discharging resistor is connected to a collector electrode of a current-limiting IGBT; and an emitter of the current-limiting IGBT is connected to the other end of the first dynamic voltage compensation module; and if a power grid to be controlled normally operates,the current-limiting IGBT is disconnected, and other devices are closed. According to the embodiment of the invention, the short-circuit current obtained when a single feeder has short circuit or thetwo feeders have short-circuit faults simultaneously can be effectively inhibited, the voltage compensation depth is increased, the current of a ground fault line is controlled to be within a certainrange, and the fault overcurrent is restrained.

The invention discloses an on-load voltage regulation device, a processing method thereof, a storage medium and a processor. The on-load voltage regulation device comprises three voltage regulation transformers, three detection devices and three controllers, wherein the three voltage regulation transformers are connected in a delta connection manner, high-voltage side coils of the three voltage regulation transformers are connected with a three-phase line, and low-voltage side coils of the three voltage regulation transformers are connected with a load; the three detection devices are connected with the three-phase line, and are used for detecting a current signal of the three-phase line; the three controllers are connected with the three detection devices, the high-voltage side coils of the three voltage regulation transformers and the load respectively, and are used for controlling the number of turns of the high-voltage side coils of the three voltage regulation transformers according to a voltage signal and/or current signal of the load. The technical problem that the stability of voltage output by the on-load voltage regulation device is low in the prior art is solved.

The invention discloses an AC/DC power supply system characterized in that a grounding device is additionally arranged between an AC system and a converter system, and the grounding device is also connected with a null line and the ground, so that the null line and a grounding point are provided for the conversion system, and the wiring mode of the conversion system is not limited to a three-phase three-wire system; a common-mode voltage elimination circuit is connected to the alternating current side and the direct current side of the conversion system, and the common-mode voltage elimination circuit is not limited to restraining common-mode voltage between the alternating current side and the direct current side of the conversion system; and meanwhile, reverse common-mode voltage of a corresponding proportion is inducted, and the reverse common-mode voltage is connected into a direct current bus and a ground wire loop in series; therefore, the ground common-mode voltage of the conversion system is eliminated.

The invention provides a method for improving the voltage quality of a power distribution network based on single-phase photovoltaic inverters. The method comprises the steps of: carrying out comprehensive application of a plurality of single-phase photovoltaic inverters distributed in the power distribution network, and forming a plurality of distributed triangular compensation groups and a plurality of distributed star-shaped compensation groups by applying the single-phase photovoltaic inverters. Each distributed triangular compensation group carries out three-phase voltage imbalance on-site compensation. The plurality of distributed star-shaped compensation groups cooperate with each other to perform power distribution network voltage deviation compensation, and the single-phase photovoltaic inverters exchange reactive capacity utilization rate information through a local communication network, calculate a reactive power reference value by adopting a distributed consistency algorithm, and achieves fairness in the same meaning of the reactive capacity utilization rate while compensating voltage deviation.