A method and apparatus for voltage compensation in rural areas

Abstract

This invention relates to the field of voltage compensation technology, specifically to a voltage compensation method and device for rural areas. At the end of a three-phase four-wire distribution network in a rural area, any two phases are input (input voltage: 300-420V). The control system, based on the real-time input voltage and load status, automatically switches the tap positions of the intelligent transformer via relays or contactors to perform automatic "voltage reduction" adjustment, thereby stabilizing the voltage output as a single-phase voltage (210-240V). Simultaneously, based on the real-time voltage and load status of the end users, and if the end voltage remains too low (<198V) after line-phase voltage adjustment, the control system quickly utilizes inverters to mobilize photovoltaic and energy storage devices to compensate for the power deficit in the end grid, raising the end voltage to 210-230V. Through this hybrid intelligent voltage regulation strategy, intelligent hybrid compensation is performed on the low voltage caused by long-distance power transmission in rural distribution networks, adjusting the end voltage to a normal level to meet normal production and living electricity needs.

Description

Technical Field

[0001] This invention relates to the field of voltage compensation technology, and in particular to a voltage compensation method and apparatus for rural areas. Background Technology

[0002] Rural power distribution networks are terminal distribution networks in the power system that provide electricity to agricultural production areas and rural residents. They are characterized by a large power supply radius and low load density. Rural power distribution networks are very important facilities for ensuring the lives of rural residents or agricultural production.

[0003] Currently, in some remote areas, end users are often far from the main transformer, resulting in insufficient voltage for these end users, which fails to reach the voltage level of the normal distribution network and affects their production and daily life. Summary of the Invention

[0004] The purpose of this invention is to provide a voltage compensation method and device for rural areas, which can automatically compensate for low voltage caused by long-distance power transmission in rural power distribution networks according to actual usage conditions, adjust the terminal electrical equipment to a normal level, and meet the normal power consumption level for production and daily life.

[0005] To achieve the above objectives, the present invention provides a voltage compensation method for rural areas, comprising the following steps: Install photovoltaic power generation devices in the terminal distribution network and connect the photovoltaic power generation devices to the distribution network and smart controller; The intelligent controller is electrically connected to the energy storage device, the intelligent transformer, and the intelligent inverter, respectively. The intelligent controller collects real-time voltage data at the end of the distribution network, performs precise and rapid intelligent analysis, and obtains specific governance measures. It quickly mobilizes one or more of the photovoltaic power generation device, the energy storage device, the transformer device, and the inverter device to perform voltage hybrid compensation until the voltage at the end of the distribution network is compensated to between 205-240V, with a voltage compensation response time of less than 0.5S.

[0006] Specifically, when the voltage of the end distribution network drops below 198V for the first time, the intelligent transformer device adjusts the coil ratio of the transformer to achieve phase voltage regulation, thereby raising the voltage of the end distribution network to 200-240V.

[0007] When the voltage of the terminal distribution network is still below 198V after the maximum voltage regulation of the line phase, the intelligent inverter converts the DC power output from the energy storage device and the photovoltaic power generation device into AC power, and adopts the output logic of photovoltaic first and then energy storage. It also uses the method of "same frequency, different amplitude, energy superposition" to provide parallel reverse compensation to the distribution network to raise the voltage of the terminal distribution network to 200-220V.

[0008] Specifically, when the terminal voltage is higher than 198V, the energy generated by the photovoltaic power generation device charges the energy storage device until the energy storage device is fully charged.

[0009] When the voltage of the terminal distribution network is higher than 198V and the energy storage device has less than 100% power, and the photovoltaic system does not have the conditions to generate electricity, the distribution network directly charges the energy storage device until the energy storage device has 100% power.

[0010] During the direct charging of the energy storage device by the distribution network, the charging power will be continuously adjusted to always keep the voltage of the terminal grid above 198V.

[0011] One of them is a voltage compensation device for rural areas, which consists of a photovoltaic power generation device, a control box, a main unit box and a mounting bracket, and uses the aforementioned voltage compensation method for rural areas to perform voltage compensation.

[0012] This invention discloses a voltage compensation method for rural areas. An intelligent controller performs precise and rapid intelligent analysis based on real-time collected voltage data at the end of the distribution network, determining specific mitigation measures. It quickly mobilizes one or more of the following devices—photovoltaic power generation devices, energy storage devices, transformer devices, and inverter devices—to perform mixed voltage compensation until the voltage at the end of the distribution network is compensated to between 200-240V. The voltage compensation response time is less than 0.5 seconds. This compensation method can automatically compensate for low voltage in rural distribution networks caused by long-distance power transmission, adjusting the end-point electrical system to a normal level to meet normal production and living electricity needs, based on actual usage conditions. Attached Figure Description

[0013] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below.

[0014] Figure 1 This is a flowchart of a voltage compensation method for rural areas according to the present invention.

[0015] Figure 2 This is a schematic diagram of the internal component installation layout of the control box of a voltage compensation device for rural areas according to the present invention.

[0016] In the diagram: 100-Control box, 200-PCS inverter, 300-DC circuit breaker, 400-Electrical component mounting plate, 500-Line-controlled circuit breaker, 600-Current transformer, 700-Surge protector, 800-Router, 900-Live / neutral parallel connection busbar, 1000-Relay. Detailed Implementation

[0017] The embodiments of the present invention are described in detail below. Examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, but should not be construed as limiting the present invention.

[0018] like Figure 1 As shown, where Figure 1 This is a flowchart of a voltage compensation method for rural areas according to the present invention. The present invention provides a voltage compensation method for rural areas, comprising the following steps: S1: Install photovoltaic power generation devices in the terminal distribution network and connect the photovoltaic power generation devices to the distribution network and the smart controller; S2: Connect the intelligent controller to the energy storage device, the intelligent transformer, and the intelligent inverter respectively; S3: The intelligent controller collects the voltage data at the end of the distribution network in real time, performs precise and rapid intelligent analysis, obtains specific governance measures, and quickly mobilizes one or more of the photovoltaic power generation device, the energy storage device, the transformer device, and the inverter device to perform voltage hybrid compensation until the voltage at the end of the distribution network is compensated to between 205-240V, with a voltage compensation response time of less than 0.5S.

[0019] It should be noted that in step S1, the photovoltaic panels of the photovoltaic power generation device can be equipped with an automatic cleaning device to facilitate timely cleaning of the photovoltaic panel surface, which helps to ensure the photovoltaic power generation effect.

[0020] It should be noted that the intelligent controller mentioned in steps S1, S2, and S3 consists of a main control chip module, a power supply module, a sensor module, an input module, and an output module. The main control chip module is used for processing and calculating the data collected by the sensor module. The intelligent controller is installed in a distribution box. A main control switch, a battery precharge switch, a photovoltaic switch, two mains switches, and a grounding busbar are all installed in the distribution box. The photovoltaic power generation device adopts a hybrid treatment device of "photovoltaic + energy storage + line-phase voltage regulation". In traditional power distribution lines, end users often face the problem of low voltage due to long transmission distances and large load fluctuations. After the photovoltaic system is connected, the end voltage can be increased by 2%-8% by compensating for load demand through local power generation.

[0021] It should be noted that the energy storage device is a long-life cycle lithium battery (5 kWh).

[0022] Preferably, when the voltage of the end distribution network drops below 198V for the first time, the intelligent transformer device adjusts the coil ratio of the transformer to achieve phase voltage regulation, thereby raising the voltage of the end distribution network to 200-240V.

[0023] Preferably, when the voltage of the end distribution network is still below 198V after the maximum voltage regulation of the line phase, the intelligent inverter converts the DC power output from the energy storage device and the photovoltaic power generation device into AC power, and adopts the output logic of photovoltaic first and then energy storage, and uses the method of "same frequency, different amplitude, energy superposition" to provide parallel reverse compensation to the distribution network to raise the voltage of the end distribution network to 200-220V.

[0024] Preferably, when the terminal voltage is higher than 198V, the energy generated by the photovoltaic power generation device charges the energy storage device until the energy storage device is fully charged.

[0025] Preferably, when the voltage of the terminal distribution network is higher than 198V and the energy storage device has less than 100% power, and the photovoltaic system does not have the conditions to generate electricity, the distribution network directly charges the energy storage device until the energy storage device has 100% power.

[0026] Preferably, during the direct charging of the energy storage device by the distribution network, the charging power will be continuously adjusted to always keep the terminal grid voltage above 198V.

[0027] When using this invention for voltage supplementation, at the end of a three-phase four-wire distribution network in a rural area, any two phases are input (input voltage: 300-420V). The control system automatically switches the tap position of the intelligent transformer through relays or contactors based on the real-time input voltage and load status, performing automatic "voltage reduction" adjustment to stabilize the voltage output as a single-phase voltage (210-240V). Simultaneously, based on the real-time voltage and load status of the end users, and if the end voltage is still too low (<198V) after line-phase voltage adjustment, the control system quickly uses the inverter to mobilize photovoltaic and energy storage devices to compensate for the power deficit in the end grid, raising the end voltage to 210-230V. Through the above-mentioned hybrid intelligent voltage regulation strategy, intelligent hybrid compensation is performed on the low voltage caused by long-distance power transmission in rural distribution networks, adjusting the end voltage to a normal level to meet the normal electricity consumption level for production and daily life.

[0028] Finally, the present invention also provides a voltage compensation device for rural areas, which consists of a photovoltaic power generation device, a control box, a main unit box and a mounting bracket, and uses the aforementioned voltage compensation method for rural areas to perform voltage compensation.

[0029] It should be noted that the photovoltaic power generation device, control box, and main unit are all installed on the utility pole using corresponding mounting brackets.

[0030] It should be noted that the control box of the rural voltage compensation device contains components such as a K1 switch, a router, a controller, and a battery. The control box is electrically connected to the main unit box. The top of the main unit box has a 3P input / output terminal block, which is equipped with 5-pin and 15-pin plugs for connecting to the control box. The outer cabinet door is equipped with a 380V voltmeter, indicator lights, a 220V voltmeter, and a power supply backup switch.

[0031] It should be noted that the startup procedure for the device is as follows: 1. Observe the voltmeter on the main unit panel; it should read 380V to confirm that the incoming line voltage is normal (340V-410V). 2. Close circuit breaker K1 inside the control box and wait for the self-test to complete for 2-3 minutes. 3. After hearing the contactor engage, observe that the indicator light on the main unit panel is lit, and that voltmeter 2 indicates normal voltage (210-235V). 4. Observe that the indicator light on the energy storage battery pack is green, indicating that the equipment is normal and ready for operation.

[0032] The above-disclosed embodiments are merely one or more preferred embodiments of this application and should not be construed as limiting the scope of this application. Those skilled in the art can understand that all or part of the processes for implementing the above embodiments and equivalent changes made in accordance with the claims of this application still fall within the scope of this application.

Claims

1. A voltage compensation method for rural areas, characterized in that, Includes the following steps: Install photovoltaic power generation devices in the terminal distribution network and connect the photovoltaic power generation devices to the distribution network and smart controller; The intelligent controller is electrically connected to the energy storage device, the intelligent transformer, and the intelligent inverter, respectively. The intelligent controller collects real-time voltage data at the end of the distribution network, performs precise and rapid intelligent analysis, and obtains specific governance measures. It quickly mobilizes one or more of the photovoltaic power generation device, the energy storage device, the transformer device, and the inverter device to perform voltage hybrid compensation until the voltage at the end of the distribution network is compensated to between 205-240V, with a voltage compensation response time of less than 0.5S.

2. The voltage compensation method for rural areas as described in claim 1, characterized in that, When the voltage of the end distribution network drops below 198V for the first time, the intelligent transformer device adjusts the coil ratio of the transformer to achieve phase voltage regulation, raising the voltage of the end distribution network to 200-240V.

3. The voltage compensation method for rural areas as described in claim 2, characterized in that, When the voltage at the end of the distribution network is still below 198V after the maximum voltage regulation of the line phase, the intelligent inverter converts the DC power output from the energy storage device and the photovoltaic power generation device into AC power, and adopts the output logic of photovoltaic first and then energy storage. It also uses the "same frequency, different amplitude, energy superposition" method to provide parallel reverse compensation to the distribution network to raise the voltage at the end of the distribution network to 200-220V.

4. The voltage compensation method for rural areas as described in claim 3, characterized in that, When the terminal voltage is higher than 198V, the energy generated by the photovoltaic power generation device charges the energy storage device until the energy storage device is fully charged.

5. The voltage compensation method for rural areas as described in claim 4, characterized in that, When the voltage of the terminal distribution network is higher than 198V and the energy storage device has less than 100% power, and the photovoltaic system does not have the conditions to generate electricity, the distribution network will directly charge the energy storage device until the energy storage device has 100% power.

6. The voltage compensation method for rural areas as described in claim 5, characterized in that, During the direct charging of the energy storage device by the distribution network, the charging power will be continuously adjusted to always keep the voltage of the terminal grid above 198V.

7. A voltage compensation device for rural areas, characterized in that, The rural voltage compensation device consists of a photovoltaic power generation device, a control box, a main unit box, and a mounting bracket, and performs voltage compensation using the rural voltage compensation method described in any one of claims 1 to 6.

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