0.4 kilovolt low voltage treatment device

Abstract

The invention discloses a 0.4 kilovolt low voltage treatment device, which belongs to the field of low voltage regulation and comprises a box body, a transformer, a double-control switch S1 and four single-control switches K1, K2, K3 and K4 are arranged in the box body, and a primary winding of the transformer is provided with three taps; the positive end of the power supply side of the distribution line is connected with the first end of a first contact of the double-control switch S1, the first end of the single-control switch K4 and the first end of a secondary winding of the transformer, the negative end of the power supply side is connected with the first end of a second contact of the double-control switch S1 and the negative end of the load side, and the second end of the first contact of the double-control switch S1 is connected with the first ends of the single-control switches K1, K2 and K3. The second ends of the single-control switches K1, K2 and K3 are respectively connected with three taps on the primary winding; the second end of the second contact of the double-control switch S1 is connected with the output end of the primary winding of the transformer, and the second end of the single-control switch K4 is connected with the output end of the secondary winding of the transformer and the positive electrode end of the load side.

Description

Technical Field

[0001] The present invention relates to the field of low-voltage intelligent voltage regulation, and in particular to a 0.4 kV low-voltage management device. Background Art

[0002] In order to ensure that the actual voltage level of the distribution line is within the allowable range of the power equipment, the line length should generally be kept within a reasonable distance range, and it is not suitable for overload operation. In my country's rural distribution network, there are generally situations such as excessive power supply radius, small line diameter, and strong load fluctuation time. Therefore, the phenomenon of unqualified voltage at the end of the rural distribution network line is also inevitable.

[0003] Voltage quality has a direct impact on the safe and economical operation of various types of equipment. For example, if the voltage is reduced, the voltage torque will decrease. When the load is rated, the rotor current will increase significantly, causing the motor temperature to rise and even burn the motor. Low voltage will also affect the use of household appliances. When the voltage is 10% lower than the rated voltage, the flux of the incandescent lamp will decrease by 30%. Low voltage will also affect the operation of air conditioners, mobile phone charging, TV signal reception, and even electrical equipment. Summary of the invention

[0004] In order to solve the problems of poor and unstable power supply quality such as voltage drop and large voltage drop caused by long power supply lines and large load fluctuations in rural 380V / 220V low-voltage distribution networks, the present invention proposes a 0.4 kV low-voltage management device with reasonable design, which solves the shortcomings of the existing technology and has good effects.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is:

[0006] A 0.4 kV low voltage treatment device comprises a box body, in which a transformer, a double-control switch S1, four single-control switches K1, K2, K3, K4 are arranged, and the primary winding of the transformer is provided with three taps;

[0007] The positive terminal on the power supply side of the distribution line is connected to the first end of contact one of the double-control switch S1, the first end of the single-control switch K4 and the input end of the secondary winding of the transformer, the negative terminal on the power supply side is connected to the first end of contact two of the double-control switch S1 and the negative terminal on the load side, the second end of contact one of the double-control switch S1 is connected to the first ends of the single-control switches K1, K2, and K3, and the second ends of the single-control switches K1, K2, and K3 are respectively connected to the three taps on the primary winding; the second end of contact two of the double-control switch S1 is connected to the output end of the primary winding of the transformer, and the second end of the single-control switch K4 is connected to the output end of the secondary winding of the transformer and the positive terminal on the load side.

[0008] Furthermore, it also includes a PLC controller and a DC regulated power supply, the DC regulated power supply supplies power to the PLC controller, and the PLC controller is electrically connected to the double-control switch S1 and the electronically controlled switches K1, K2, K3, and K4.

[0009] Furthermore, there are 4 gears in total, including 3 boost adjustment gears and 1 bypass gear.

[0010] Furthermore, the PLC controls S1 to close and K4 to open, and switches different boost adjustment gears by controlling K1 to close, K2 and K3 to open, or K2 to close, K1 and K3 to open, or K3 to close, K1 and K2 to open; when the voltage is normal or a device failure occurs, it switches to the 1-way bypass gear, and the PLC controls S1 to open and K4 to close.

[0011] Furthermore, two modes are included: automatic voltage regulation and manual exit.

[0012] Furthermore, the device is installed at the end of the line and on a pole bracket or a cement platform, and the device casing is grounded.

[0013] Beneficial technical effects brought by the present invention:

[0014] The present invention can effectively solve the voltage quality problem of users and ensure normal power supply by adjusting and compensating the voltage in the middle or at the end of the line. It has an automatic adjustment function. Even if the equipment fails, it will automatically switch to bypass without frequent maintenance. The input voltage fluctuation automatically adjusts the boost amplitude. After the low voltage is eliminated, the address can be flexibly changed for repeated installation and use. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a circuit schematic diagram of a 0.4 kV low voltage management device in the present invention;

[0016] Figure 2 This is a voltage regulation principle diagram of a 0.4 kV low voltage management device in the present invention;

[0017] Figure 3 This is a schematic diagram of the installation of a 0.4 kV low voltage management device in the present invention; DETAILED DESCRIPTION

[0018] The specific implementation of the present invention is further described below in conjunction with specific embodiments:

[0019] A 0.4 kV low voltage treatment device comprises a box body, in which a transformer, a double-control switch S1, four single-control switches K1, K2, K3, K4 are arranged, and the primary winding of the transformer is provided with three taps;

[0020] like Figure 1As shown, the positive terminal on the power supply side of the distribution line is connected to the first end of contact one of the double-control switch S1, the first end of the single-control switch K4 and the input end of the secondary winding of the transformer, the negative terminal on the power supply side is connected to the first end of contact two of the double-control switch S1 and the negative terminal on the load side, the second end of contact one of the double-control switch S1 is connected to the first ends of the single-control switches K1, K2, and K3, and the second ends of the single-control switches K1, K2, and K3 are respectively connected to the three taps on the primary winding; the second end of contact two of the double-control switch S1 is connected to the output end of the primary winding of the transformer, and the second end of the single-control switch K4 is connected to the output end of the secondary winding of the transformer and the positive terminal on the load side.

[0021] The device also includes a PLC controller and a DC regulated power supply, the DC regulated power supply supplies power to the PLC controller, and the PLC controller is electrically connected to the double-control switch S1 and the electric control switches K1, K2, K3, and K4. The device has a total of 4 gears, including 3 boost adjustment gears and 1 bypass gear, including automatic voltage regulation and manual exit modes.

[0022] The PLC controls S1 to close and K4 to open, and switches different boost adjustment gears by controlling K1 to close, K2 and K3 to open, or K2 to close, K1 and K3 to open, or K3 to close, K1 and K2 to open; when the voltage is normal or the device fails, it switches to the 1-way bypass gear, and the PLC controls S1 to open and K4 to close.

[0023] The device is installed at the end of the line. The device can be installed on a pole bracket or a cement platform, and the device casing is grounded.

[0024] like Figure 2 As shown, the output voltage of the terminal transformer is Us, and the load current forms a voltage drop on the line. When the line is too long or the load increases, the voltage at L2 may be lower than the minimum allowable voltage value. A voltage regulating device is installed at L2. When the device is in boost mode, the voltage is increased by ΔU, so that the voltage UL at the load end is increased to U+ΔU to achieve the qualified voltage value.

[0025] Reference power supply radius and installation location: The effect of installing this equipment within a power supply radius of less than 2 kilometers is very good. If the load at the end is light and the wire diameter meets the basic requirements, the power supply radius can be extended; the device is generally installed at the end of the line, as close as possible to low-voltage users and the main line end pole. If the voltage is too low due to the extension of the power supply radius, the installation position should be moved forward appropriately.

[0026] like Figure 3 As shown, after the installation point is determined, install the bracket and diagonal brace at a distance of more than 1.5 meters from the ground on the pole or in front of the user's incoming electricity meter. After the installation is firm, hoist the device into place. The bottom plate of the device is firmly fixed to the bracket with 4 M12 bolts. After the device is fixed in place, install the grounding device and connect it firmly to the shell.

[0027] The unusable conditions are: the power supply radius is too large, the wire diameter does not meet the basic requirements, and the load is too large. When the above three conditions occur at the same time, it is not suitable to install this device.

[0028] The working mechanism of single-phase voltage regulation is: the voltage regulating device is connected in series near the load at the end of the line. When the load voltage is low, the voltage regulating device is automatically put into operation to adjust the voltage at the load to U+ΔU, so that the voltage at the load reaches the qualified voltage value.

[0029] The working mechanism of three-phase voltage regulation is: three voltage regulating devices are used to regulate the voltage in different phases, so as to achieve the three-phase voltage regulation without interference with each other, and avoid the situation that one phase voltage is low and the other phase voltage is high, resulting in three-phase imbalance.

[0030] This device must be installed in series after power failure; parallel installation is not allowed.

[0031] Of course, the above description is not a limitation of the present invention, and the present invention is not limited to the above examples. Changes, modifications, additions or substitutions made by technicians in this technical field within the essential scope of the present invention should also fall within the protection scope of the present invention.

Claims

1. A 0.4 kV low voltage control device, characterized in that: It includes a box body, in which a transformer, a double-control switch S1, four single-control switches K1, K2, K3, K4 are arranged, and the primary winding of the transformer is provided with three taps; The positive terminal on the power supply side of the distribution line is connected to the first end of contact one of the double-control switch S1, the first end of the single-control switch K4 and the input end of the secondary winding of the transformer, the negative terminal on the power supply side is connected to the first end of contact two of the double-control switch S1 and the negative terminal on the load side, the second end of contact one of the double-control switch S1 is connected to the first ends of the single-control switches K1, K2, and K3, and the second ends of the single-control switches K1, K2, and K3 are respectively connected to the three taps on the primary winding; the second end of contact two of the double-control switch S1 is connected to the output end of the primary winding of the transformer, and the second end of the single-control switch K4 is connected to the output end of the secondary winding of the transformer and the positive terminal on the load side.

2. A 0.4 kV low voltage control device according to claim 1, characterized in that: It also includes a PLC controller and a DC regulated power supply, wherein the DC regulated power supply supplies power to the PLC controller, and the PLC controller is electrically connected to the double-control switch S1 and the electronically controlled switches K1, K2, K3, and K4.

3. A 0.4 kV low voltage control device according to claim 2, characterized in that: There are 4 gears in total, including 3 boost adjustment gears and 1 bypass gear.

4. A 0.4 kV low voltage treatment device according to claim 3, characterized in that: The PLC controls S1 to close and K4 to open, and switches different boost adjustment gears by controlling K1 to close, K2 and K3 to open, or K2 to close, K1 and K3 to open, or K3 to close, K1 and K2 to open; When the voltage is normal or the device fails, it switches to bypass position 1, and the PLC controls S1 to open and K4 to close.

5. A 0.4 kV low voltage control device according to claim 4, characterized in that: It includes two modes: automatic voltage regulation and manual exit.

6. A 0.4 kV low voltage treatment device according to claim 5, characterized in that: The device is installed at the end of the line and on a pole bracket or cement platform, with the device casing grounded.

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