CN204928124U - A distribution network terminal with power compensation - Google Patents

Abstract

The utility model discloses a distribution network terminal with power compensation. The current transformer and the voltage transformer are connected with an A/D conversion circuit module, and the A/D conversion circuit module is connected with a single-chip microcomputer. The main circuit The module is connected with the single-chip microcomputer through the pulse trigger circuit, and the display module and the keyboard are connected with the single-chip microcomputer. The design scheme adopted by the utility model improves and enhances the voltage quality of the electric power system, fully exerts the effectiveness of the transmission and transformation substation equipment, reduces power loss, and ensures safe and economical operation of the power grid.

Description

A distribution network terminal with power compensation

technical field

The utility model relates to a distribution network terminal with power compensation, belonging to the technical field of distribution networks.

Background technique

In factories and mines electricity enterprises, the equipment that uses electricity is mainly motors, electromagnetic coils, transformers, etc. These load inductances are large, resulting in low power factor of power supply lines, large loss of current and energy lines, low economic efficiency, and waste of electric energy. To improve the safe operation level and power quality of the power grid, in addition to the reasonable structure of the power grid itself, advanced adjustment and control methods must be provided. The safe and economical operation of the power grid depends to a large extent on its "controllability". The active or reactive power compensation provided by parallel compensation can play an irreplaceable important role in enhancing the overall stability of the power system. Therefore, since the birth of the power system, parallel compensation technology has begun to appear in the power system.

The existing distribution network terminal power compensation system has unreasonable design, complex circuit structure, low degree of control automation and intelligence, and extremely inconvenient maintenance.

Utility model content

The utility model proposes a power distribution network terminal with power compensation. The adopted design scheme improves and enhances the voltage quality of the power system, fully exerts the efficiency of the transmission and transformation substation equipment, reduces power loss, and ensures safe and economical operation of the power grid.

A distribution network terminal with power compensation of the utility model includes: a current transformer, a voltage transformer, an A/D conversion circuit module, a main circuit module, a single-chip microcomputer, a display module, a keyboard, and a pulse trigger circuit. The current transformer and the voltage transformer are connected with the A/D conversion circuit module, the A/D conversion circuit module is connected with the single-chip microcomputer, the main circuit module is connected with the single-chip computer through the pulse trigger circuit, and the display module and the keyboard are connected with the single-chip computer Above, the single-chip microcomputer adopts 80C196KB chip, the current transformer is SPT205B current transformer, the voltage transformer is SPT204A voltage transformer, the A/D conversion circuit module adopts MAX197 conversion chip, and the keyboard The I/O of the 80C196KB chip is used as input, the display module adopts an LCD display, the keyboard adopts the I/O of the 80C196KB chip as input, the display module adopts an LCD display, and the main circuit module is composed of thyristors T1 and T2 , T3...T6 and diodes D1, D2, D3...D6 and capacitors C1, C2, C3...C6.

Further, the thyristors T1, T2, T3...T6 and the diodes D1, D2, D3...D6 are respectively connected to the grid bus A, B, C, and the thyristors T1, T2, T3.... ..T6 is connected in parallel with diodes D1, D2, D3...D6. The voltage and current values measured on the grid bus are converted from analog to digital by the A/D conversion circuit module, and then communicated with the microcontroller connected.

Further, in the internal circuit of the voltage transformer, a current-limiting resistor Ri is provided at the input end. In the internal circuit of the current transformer, the input: output current is 3:1, the rated input current is 3mA, and the rated output is 1mA, voltage transformer circuit and current transformer main circuit convert A, B, C phase voltage and line current into -10V—+10V AC voltage signal and send it to A/D conversion circuit for AC sampling and conversion. No matter how large the input voltage is, adjust the value, R1<5, so that the input current value is 2mA, then the other side will also sense and output the same current 2mA, and the required output voltage can be obtained by adjusting the resistors R and w , adjust r and C to compensate for phase shift.

Further, in the internal circuit of the A/D conversion circuit module, a 100pf capacitor is connected between the CLK pin of the MAX197 conversion chip and the ground, CH0-CH3 of the MAX197 conversion chip is connected to the current transformer and the voltage transformer, and D0- D7 is connected with the microcontroller pin.

The beneficial effects of the utility model are: the design scheme adopted by the utility model improves and enhances the voltage quality of the power system, fully exerts the efficiency of the transmission and transformation substation equipment, reduces power loss, and ensures safe and economical operation of the power grid.

Description of drawings

For ease of description, the utility model is described in detail by the following specific implementation and accompanying drawings;

Fig. 1 is a block diagram of the utility model;

Fig. 2 is a circuit diagram of the main circuit module;

Fig. 3 is the internal circuit diagram of the voltage transformer;

Fig. 4 is the internal circuit diagram of the current transformer;

Fig. 5 is an internal circuit diagram of the A/D conversion circuit module.

Detailed ways

In order to make the purpose, technical solutions and advantages of the utility model clearer, the utility model is described below through specific embodiments shown in the accompanying drawings. However, it should be understood that these descriptions are only exemplary and not intended to limit the scope of the present invention. In addition, in the following description, descriptions of known structures and technologies are omitted to avoid unnecessarily confusing the concept of the present invention.

As shown in Figures 1, 2, 3, 4, and 5, a distribution network terminal with power compensation includes: current transformer, voltage transformer, A/D conversion circuit module, main circuit module, single-chip microcomputer, and display module , keyboard, pulse trigger circuit, described current transformer and voltage transformer are connected with A/D conversion circuit module, A/D conversion circuit module is connected with single-chip microcomputer, described main circuit module is connected with single-chip microcomputer through pulse trigger circuit, Described display module, keyboard are connected on the single-chip microcomputer, and described single-chip microcomputer adopts 80C196KB chip, and described current transformer is SPT205B current transformer, and voltage transformer is SPT204A voltage transformer, and described A/D conversion circuit The module adopts the MAX197 conversion chip, the keyboard adopts the I/O of the 80C196KB chip as the input, the display module adopts the LCD display, the keyboard adopts the I/O of the 80C196KB chip as the input, and the display module adopts the LCD display. The main circuit module is composed of thyristors T1, T2, T3...T6, diodes D1, D2, D3...D6 and capacitors C1, C2, C3...C6.

Specifically, as shown in Figure 2, in the main circuit module, A, B, and C are power grid busbars, T1, T2, T3...T6 are thyristors, D1, D2, D3... ...D6 is a diode, thyristors T1, T2, T3...T6 and diodes D1, D2, D3...D6 are respectively connected to grid bus A, B, C, thyristors T1, T2, T3...T6 and diodes D1, D2, D3...D6 are connected in parallel, and the voltage value and current value measured on the grid bus are converted to analog by the A/D conversion circuit module Convert to digital quantity, then be connected with single-chip microcomputer, as shown in Figure 3 and Figure 4, in the internal circuit of described voltage transformer, the Ri of input terminal is current-limiting resistor, in the internal circuit diagram of described current transformer, input: output The current is 3:1, the rated input current is 3mA, and the rated output is 1mA. The voltage transformer circuit and the current transformer main circuit convert the phase voltages and currents of A, B, and C into -10V—— The +10V AC voltage signal is sent to the A/D conversion circuit for AC sampling and conversion. In the internal circuit diagram of the voltage transformer, no matter how large the input voltage is, the adjusted value, R1<5, makes the value of the input current If it is 2mA, the other side will also sense and output the same current 2mA, adjust the resistors R and w to obtain the required output voltage, adjust r and C to compensate for the phase shift, as shown in Figure 5, the A In the internal circuit of the /D conversion circuit module, a 100pf capacitor is connected between the CLK pin and the ground to set the internal clock frequency, CH0-CH3 receives the analog signal transmitted by the current transformer and voltage transformer, and D0-D7 is connected to the pins of the microcontroller.

Claims (4)

1. one kind has the power distribution network terminal of power back-off, it is characterized in that: comprise current transformer, voltage transformer, A/D change-over circuit module, main circuit module, single-chip microcomputer, display module, keyboard, pulsed triggering circuit, described current transformer and voltage transformer respectively with A/D change-over circuit model calling, A/D change-over circuit module is connected with single-chip microcomputer, described main circuit module is connected with single-chip microcomputer by pulsed triggering circuit, and described display module, keyboard are connected on single-chip microcomputer.

2. a kind of power distribution network terminal with power back-off according to claim 1, it is characterized in that: described single-chip microcomputer adopts 80C196KB chip, described current transformer is SPT205B current transformer, voltage transformer is SPT204A voltage transformer, described A/D change-over circuit module adopts MAX197 conversion chip, described keyboard adopts the I/O of 80C196KB chip as input, and display module adopts LCD display.

3. a kind of power distribution network terminal with power back-off according to claim 1, it is characterized in that: described main circuit module is made up of thyristor T1, T2, T3......T6 and diode D1, D2, D3......D6 and electric capacity C1, C2, C3....C6, thyristor T1, T2, T3......T6 and diode D1, D2, D3......D6 are connected with electrical network bus A, B, C respectively, and thyristor T1, T2, T3......T6 and diode D1, D2, D3......D6 are connected in parallel.

4. a kind of power distribution network terminal with power back-off according to claim 1, it is characterized in that: in described voltage transformer internal circuit, current-limiting resistance Ri is provided with at input, in described current transformer internal circuit, input: the electric current of output is 3:1, in described A/D change-over circuit inside modules circuit, the CLK pin of MAX197 conversion chip be connected a 100pf electric capacity between ground, CH0-CH3 pin of MAX197 conversion chip is connected with current transformer and voltage transformer, and D0-D7 pin is connected with single-chip microcomputer pin.