CN201877781U - Ground power overvoltage reversed-polarity protector of power system - Google Patents

Abstract

The utility model discloses a ground power overvoltage reverse polarity protector for a power system, which includes a ground power socket 31P, a line protection circuit breaker 32P, a voltage sensitive switch T7, a switching diode D5, a switching diode D6, and a control relay R3 , control relay 2 R4, ground power grid-connected contactor K6; line protection circuit breaker 32P, voltage sensitive switch T7, switching diode 2 D6, control relay 2 R4 in series to form the overvoltage delay control circuit part; ground power socket 31P, switching diode A D5, a control relay and a R3 are connected in series to form the control circuit part. Because the utility model is equipped with a voltage sensitive switch in the protector, it can ensure that the ground power supply voltage is too high to not supply power to the equipment grid; and because the switch diode has the characteristic of one-way conduction, the polarity of the ground power input and the polarity of the equipment grid can be guaranteed. On the contrary, it can prevent the ground power from being input to the equipment grid, and protect the equipment's electrical equipment and power supply lines.

Description

A power supply system ground power overvoltage reverse polarity protector

technical field

The utility model belongs to the power supply protection technology and relates to overvoltage and reverse polarity protection equipment for a power supply system.

Background technique

At present, general-purpose aircraft do not have an overvoltage protection circuit for ground power supply, and when the polarity of the grid-connected ground power supply is opposite to that of the aircraft grid, it will cause partial damage to the lines of the power supply system.

Contents of the invention

The purpose of the utility model is to design a protector for overvoltage and reverse polarity protection of the ground power supply.

The technical scheme of the utility model is: a power supply system ground power overvoltage reverse polarity protector, including ground power socket 31P, line protection circuit breaker 32P, voltage sensitive switch T7, switch diode one D5, switch diode two D6, control Relay 1 R3, control relay 2 R4, ground power grid contactor K6; line protection circuit breaker 32P, voltage sensitive switch T7, switching diode 2 D6, control relay 2 R4 in series to form the overvoltage delay control circuit part; ground power socket 31P , switch diode-D5, and control relay-R3 are connected in series to form the control circuit part; the positive pole of the ground power socket 31P is connected with the ground power grid-connected contactor K6 moving contact and the switch diode-D5 through wires; the switch diode-D5 is connected through wires It is connected with the control relay-R3 coil contact; the control relay-R3 coil contact is connected with the negative terminal of the grid through a wire; the ground power socket 31P negative pole is connected with the grid negative terminal through a wire; the ground power socket 31P positive wire The control terminal is connected with the line protection circuit breaker 32P through wires; the line protection circuit breaker 32P is connected with the voltage sensitive switch T7 and the moving contact of the control relay R3 through wires; the voltage sensitive switch T7 is connected with the switch diode D6 through wires Connected together; the switching diode 2 D6 is connected with the coil contact of the control relay 2 R4 through a wire; the coil contact of the control relay 2 R4 is connected with the negative terminal of the grid through a wire; the 2 groups of moving parts of the control relay 2 R4 The two moving contacts of the control relay are respectively connected to the two moving contacts of the two groups of moving parts of the control relay one R3 through wires; the other two moving contacts of the two groups of moving parts of the control relay two R4 The contacts are respectively connected with the coil contacts of the ground power grid-connected contactor K6 through wires.

The utility model has the advantages that: since the protector is provided with a voltage sensitive switch T7, it is ensured that the ground power supply voltage is too high to not supply power to the equipment grid; When the polarity of the equipment is opposite to that of the equipment grid, it can prevent the ground power from being input to the equipment grid, and protect the equipment's electrical equipment and power supply lines.

Description of drawings

Figure 1 is the grid-connected circuit diagram of the original ground power supply;

Fig. 2 is a schematic diagram of the utility model power overvoltage reverse polarity protector.

Detailed ways

Below the utility model is described in further detail.

In Fig. 1, the ground power supply is input into the power grid through the ground power socket 31P, as long as its voltage can make the working coil of the contactor 72P pull in, the ground power supply can be connected to the entire power grid of the aircraft. However, once the voltage connected to the aircraft power grid is too high, some electrical equipment of the aircraft will be damaged due to the high voltage; Because the isolation function of the diode does not work, it prevents the ground power supply from being incorporated into the grid, but the wire PB13-20, diode 84P and wire PB10-18N in the power line will form a short circuit and burn down.

"PB2-2N", "PB5-2", "PB11-20", "PB10-18N", "PB13-20" and "PB6-18N" in Figure 1 represent the wires connecting the wires between the components No., the line number is composed as follows (take PB2-2N as an example, the rest are the same as PB2-2N):

In Fig. 2, the ground power socket 31P, the switching diode D5, and the control relay R3 are connected in series to form the control circuit part; the positive pole of the ground power socket 31P is connected with the moving contact of the ground power grid contactor K6 and the switching diode D5 through wires; The switching diode D5 is connected with the coil contact of the control relay R3 through a wire; the coil contact of the control relay R3 is connected with the negative terminal of the grid through a wire; the ground power socket 31P negative pole is connected with the negative terminal of the power grid through a wire; the ground power socket The control terminal of the 31P positive line is connected with the line protection circuit breaker 32P through the wire; the line protection circuit breaker 32P is connected with the voltage sensitive switch T7 and the moving contact of the control relay R3 through the wire; the voltage sensitive switch T7 is connected with the switch through the wire The diode D6 is connected together; the switching diode D6 is connected with the coil contact of the control relay R4 through a wire; the coil contact of the control relay R4 is connected with the negative terminal of the grid through a wire; The two moving contacts are respectively connected to the two moving contacts in the two groups of moving parts of the control relay R3 through wires; the other two moving contacts in the two groups of moving parts of the control relay R4 are connected through wires They are respectively connected to the coil contacts of the ground power grid contactor K6; the ground power is input to the aircraft power grid through the ground power socket 31P. When the ground power supply voltage is higher than 33V, T7 is disconnected with a delay of 50ms to make the control relay R4 work. The coil is disconnected, and T7 will not be connected again before the ground power supply is disconnected (voltage disappears), so as to ensure that the control relay R4 and the ground power grid contactor K6 do not work, preventing the ground power supply from supplying power to the aircraft grid; when the ground power supply passes through 31P When the polarity of the input grid is opposite to that of the aircraft grid, the switching diodes D5 and D6 cut off the working coil lines of the relays R3 and R4, and the relays R3 and R4 do not work, so that the contactor K6 does not work, preventing the ground power from supplying power to the aircraft grid .

The ground power supply overvoltage reverse polarity protector of the power system is used in the design of a certain type of aircraft power system. The main technical parameters of each component to realize its function are as follows:

Ground power socket 31P: rated current: 500A, withstand voltage: 1500V

Voltage sensitive switch T7: 33±1V, delay 50±5ms

Line protection circuit breaker 32P: rated current 5A

Switching diode: rated forward operating current is 1A

Control relay R3, R4: rated voltage: 28V, rated current: 12A, coil resistance: 290Ω

Ground power grid-connected contactor K6: rated voltage: 28V, rated current: 400A

Claims (1)

1. A power supply system ground power overvoltage reverse polarity protector, comprising ground power socket (31P), line protection circuit breaker (32P), voltage sensitive switch (T7), switch diode one (D5), switch diode two ( D6), control relay one (R3), control relay two (R4), ground power grid contactor (K6); it is characterized in that line protection circuit breaker (32P), voltage sensitive switch (T7), switch diode two ( D6), the control relay two (R4) are connected in series to form the overvoltage delay control circuit part; the ground power socket (31P), the switching diode one (D5), and the control relay one (R3) are connected in series to form the control circuit part; the ground power socket (31P) The anode is connected together with the moving contact of the ground power grid-connected contactor (K6) and the switching diode one (D5) through a wire; the switching diode one (D5) is connected with the coil contact of the control relay one (R3) through a wire; The coil contact of the control relay 1 (R3) is connected with the negative terminal of the power grid through a wire; the negative pole of the ground power socket (31P) is connected with the negative terminal of the power grid through a wire; The protective circuit breaker (32P) is connected together; the line protective circuit breaker (32P) is connected together with the voltage sensitive switch (T7) and the moving contact of the control relay one (R3) through the wire; the voltage sensitive switch (T7) is connected with the Switching diode 2 (D6) is connected together; switching diode 2 (D6) is connected with the coil contact of control relay 2 (R4) through a wire; the coil contact of control relay 2 (R4) is connected with the grid negative terminal through a wire ; The two moving contacts in the 2 groups of moving parts of the control relay 2 (R4) are respectively connected with the 2 moving contacts of the 2 groups of moving parts of the control relay 1 (R3) through wires; The other two moving contacts in the two groups of moving parts of the relay 2 (R4) are respectively connected to the coil contacts of the ground power grid-connected contactor (K6) through wires. the

Images