CN209805421U - Switch connecting circuit suitable for low-voltage compensation voltage regulating device - Google Patents

Abstract

The utility model is a switch connection circuit suitable for a low-voltage compensation voltage regulating device, which includes a compensation transformer with a tap, and is characterized in that it also includes at least one set of magnetic latching relays with a conversion contact structure, and a magnetic relay with a conversion contact structure. The holding relay is connected to a tapped compensating transformer. Since at least one set of magnetic latching relays with transfer contact structure is used to connect with a compensation transformer with a tap type, the power supply of the load can be naturally compensated without power interruption, and a stable voltage output can be obtained to meet the user's power consumption requirements. It has the advantages of simple structure, high reliability, low power consumption, strong anti-interference, low cost, no need for manual maintenance, no power failure, no surge, no jitter during switching.

Description

A switch connection circuit suitable for low-voltage compensation and voltage regulation device

technical field

The utility model relates to the technical field of electric energy quality, in particular to a switch connection circuit suitable for a low-voltage compensation voltage regulating device.

Background technique

At present, the standard voltage of China's mains electricity is AC: 50Hz, 220V. Civilian loads can work normally under this voltage. The 220V is output through a transformer and transmitted to users through the power grid. If the user is at the end of the grid, especially in remote rural areas, the voltage is lower than the standard voltage when the power is transmitted to the end of the grid due to the conversion of electric energy into heat energy and other forms of energy loss in the transmission process. The existing technology is usually at the end of the grid or In the middle, a matching booster device is installed to boost the terminal or intermediate voltage. The existing techniques for compensating booster devices are as follows:

(1) Through the compensation method of putting capacitors in parallel in the power grid, the voltage can be raised by using the principle of overcompensation. This method can raise the voltage, but the consequence is that the reactive power value in the power grid is increased and the power factor of the power grid is reduced. The compensation voltage also has other impacts on the grid. Moreover, the compensation efficiency of the capacitor overcompensation method is low, and the compensation effect is not obvious;

(2) With the development of science and technology, the boosted voltage can be adjusted through the inverter circuit composed of IGBT transistors to adjust the voltage at the end of the power grid. Although the voltage of the power grid can be improved, it has poor safety and stability, low efficiency, high power consumption, and high cost. Shortcomings such as high temperature and short life are gradually exposed in actual use. Especially when there is a short-circuit fault in the lower-level power supply, it is very likely to cause the internal core component IGBT to burn out, resulting in irreversible consequences. Therefore, this scheme is extremely rare in practical applications;

(3) Now through the combination of the tapped compensation transformer and the quick contactor, the voltage compensation for the switch of the primary tap of the compensation transformer is completed. The principle is to change the relationship between the winding turns of the primary side and the secondary side of the compensation transformer, so The principle of voltage superposition changes the voltage value output by the secondary side to complete the adjustment of the voltage, but the driving circuit of this method is complex, and the safety and reliability are low. If the contactor jitters when it operates, it will cause fluctuations in the output voltage, and even burn down the lower-level electrical equipment. The protection measures of this circuit mode are generally controlled by software programs. If the hardware fails, it will cause a short circuit in the winding of the voltage transformer, resulting in unnecessary economic losses and serious consequences. And during the operation of the equipment, the quick contactor needs to pass a certain continuous current to maintain the current pull-in state, so it produces a waste of electric energy and increases the power consumption of the equipment itself. If it is operated for a long time, the internal coil will generate a certain The thermal energy shortens the life of the quick contactor itself.

Contents of the invention

The purpose of this utility model is to overcome the shortcomings of the prior art, to provide a simple structure, high reliability, low power consumption, strong anti-interference, low cost, no need for manual maintenance, no power failure, no inrush current during the switching process, A jitter-free switching connection circuit suitable for low voltage compensating voltage regulating devices.

The technical solution adopted to realize the purpose of this utility model is a switch connection circuit suitable for a low-voltage compensation and voltage regulating device, which includes a compensation transformer with a tap, and is characterized in that it also includes at least one set of magnetic latches with a conversion contact structure. For a relay, the magnetic latching relay with a changeover contact structure is connected to a compensation transformer with taps.

A switch connection circuit suitable for a low-voltage compensation and voltage regulating device of the utility model can realize the power supply to the load without any delay due to the connection between at least one set of magnetic latching relays with a conversion contact structure and a compensation transformer with a tap type. Natural compensation for power outage, stable voltage output, meeting user's electricity requirements, simple structure, high reliability, low power consumption, strong anti-interference, low cost, no need for manual maintenance, no power outage, no trouble during switching Inrush current, no jitter and other advantages.

Description of drawings

Fig. 1 is a schematic diagram of a switch connection circuit suitable for a low-voltage compensation and voltage regulating device according to Embodiment 1;

Fig. 2 is a working flow diagram of a switch connection circuit suitable for low-voltage compensation and voltage regulation device in embodiment 1;

Fig. 3 is a schematic diagram of a switch connection circuit suitable for a low-voltage compensation and voltage regulating device according to Embodiment 2;

FIG. 4 is a working flow chart of a switch connection circuit suitable for a low-voltage compensation and voltage regulation device in Embodiment 2. FIG.

In the figure: the magnetic latching relay with a conversion contact structure is a single-pole double-throw magnetic latching relay, which are KA1, KA2, KA3 and KA4; a compensation transformer T with taps.

Detailed ways

Utilize accompanying drawing and embodiment to further illustrate the utility model below.

Embodiment 1: Referring to FIG. 1, in a switch connection circuit suitable for low-voltage compensation and voltage regulating devices in Embodiment 1, the single-pole double-throw magnetic latching relays KA1 and KA2 respectively include three contacts, which are respectively ① common contact, ② normal contact Closed contact (① and ②), ③ normally open contact (① and ③); the ① contact of the single-pole double-throw magnetic latching relay KA1 in the circuit is connected to the incoming line of the power supply, and is connected to the secondary side of a compensation transformer T with a tap The tap ④ is connected, the point ② of the single-pole double-throw magnetic latching relay KA1 in the circuit is connected to the secondary tap ⑤ of a compensation transformer T with a tap, and connected to the outgoing line, the point ③ of the single-pole double-throw magnetic latching relay KA1 It is connected with point ① of SPDT latching relay KA2; point ① of SPDT latching relay KA2 is connected with point ③ of SPDT latching relay KA1; point ② of SPDT latching relay KA2 is connected with a The tap ① of the primary side of the compensation transformer T with taps is connected, and the point ③ of the single-pole double-throw magnetic latching relay KA2 is connected with the tap ② of the primary side of a compensation transformer T with taps, and the primary side of a compensation transformer T with taps The tap ③ is connected to the neutral line of the circuit. The circuit is divided into three working modes, which are respectively defined as bypass mode, low compensation mode and high compensation mode, which are respectively applicable to three different on-site working conditions. There are two cases of bypass mode, one of which is applicable to the circuit If the compensation control system detects that the incoming line voltage of the circuit meets the standard voltage requirement of the load side, and no compensation is required, the switch will be in bypass mode; If the operating conditions of the low-voltage compensation and voltage regulating device cannot be compensated, the switching will be in bypass mode; the low compensation mode is suitable for the compensation control system of this circuit. The system will switch the circuit to the low compensation mode; the high compensation mode is suitable for the phenomenon that the compensation control system detects that the incoming line voltage is under voltage, and it does not meet the load operation at all, then the circuit will be switched to the high compensation mode .

Bypass mode: The ① and ② normally closed contacts of the single-pole double-throw magnetic latching relay KA1 are closed, and the incoming line directly forms a path with the outgoing line without going through a compensation transformer T with a tap for voltage compensation. At this time, because ③ and ① of KA1 are disconnected, KA2 does not work.

Low compensation mode: The ① and ③ normally open contacts of the SPDT magnetic latching relay KA1 are closed, the incoming line is connected to the ④ point of a compensation transformer T with a tap, and passes through the ① and ③ of the SPDT magnetic latching relay KA1 Connect point ① of the single-pole double-throw magnetic latching relay KA2 with point ③ of the single-pole double-throw magnetic latching relay KA1. At this time, the single-pole double-throw magnetic latching relay KA2 is the decision relay for determining the low compensation mode and the high compensation mode. If the ① and ② normally closed contacts of the SPDT magnetic latching relay KA2 are closed, the incoming line passes through the SPDT magnetic latching relay KA1 The contacts of the SPDT magnetic latching relay KA2 are connected to tap ① of a compensation transformer T with taps, and the compensation transformer T with taps works in low compensation mode. The outgoing line voltage is the compensation voltage of the primary side, which is electromagnetically induced to a voltage on the secondary side and added to the intrinsic line voltage value of the secondary side at the same time.

High compensation mode: The ① and ③ normally open contacts of the SPDT magnetic latching relay KA1 are closed, the incoming line is connected to the ④ point of a compensation transformer T with a tap, and passes through the ① and ③ of the SPDT magnetic latching relay KA1 Connect point ① of the single-pole double-throw magnetic latching relay KA2 with point ③ of the single-pole double-throw magnetic latching relay KA1. At this time, the single-pole double-throw magnetic latching relay KA2 is the decision relay for determining the low compensation mode and the high compensation mode. If the ① and ③ normally open contacts of the single-pole double-throw magnetic latching relay KA2 are closed, the incoming line passes through the single-pole double-throw magnetic latching relay. The contacts of KA1 and SPDT magnetic latching relay KA2 are connected to tap ② of a compensation transformer T with taps, and the compensation transformer T with taps works in high compensation mode. The outgoing line voltage is the compensation voltage of the primary side, which is electromagnetically induced to a voltage on the secondary side and added to the intrinsic line voltage value of the secondary side at the same time. The feature of this circuit is that it can determine which working mode to work through the internal program or external command control through the low-voltage compensation and voltage regulation device, and it can communicate with the main controller or other controllers through the wireless network such as 433M LORA or ZIGBEE of the low-voltage compensation and voltage regulation device. Free network operation realizes unified control and operation of multiple commutation switch devices. It can also access the Internet through the GPRS public wireless network to realize remote monitoring. The biggest feature of this circuit is that it adopts two or more sets of magnetic latching relays with conversion contact structure, that is, two or more sets of single-pole double-throw magnetic latching relays are connected with a compensation transformer T with a tap. When the holding relay fails, no matter what state it stays in, it will not cause a short circuit of the T winding of the compensation transformer with a tap. It belongs to a very safe locking structure and makes up for the defects of the traditional circuit.

Referring to Fig. 2, a switch connection circuit suitable for a low-voltage compensation and voltage regulation device in Embodiment 1 adopts the low-voltage compensation and voltage regulation device of the prior art, and creatively designs a switch connection circuit connected to it, which has three working modes , mainly according to the voltage situation of the incoming line to reasonably switch the corresponding working mode. Analyze the voltage data of the incoming line, and then make a selection judgment. First, judge whether the execution conditions of the program in the low-voltage compensation voltage regulating device are met, that is, whether the current incoming line voltage can meet the operating conditions of the switch connection circuit described in the utility model. , if the operating conditions are met, the low-voltage compensation voltage regulating device controls the normally open contact of the single-pole double-throw magnetic latching relay KA1 to close, and the normally closed contact to open, the system switches from the bypass state to the working state, and at the same time controls the single-pole double-throw The normally closed contact of the latching relay KA2 is closed, so that the circuit enters the low compensation mode. Secondly, if the voltage of the incoming line does not meet the operating conditions of the low-voltage compensation voltage regulating device, the system maintains the bypass mode, that is, the single-pole double-throw magnetic latching relay KA1 keeps the normally closed contacts closed.

When the system is in low compensation mode, the low-voltage compensation and voltage regulating device continuously detects the voltage of the incoming line. If the incoming line voltage meets the state of high compensation mode, the low-voltage compensation and voltage regulating device controls the single-pole double-throw magnetic latching relay KA1 to maintain the normal state. The open contact is closed, and at the same time, the normally closed contact of the single pole double throw magnetic latching relay KA2 is controlled to open, and the normally open contact is closed. At this time, the circuit works in the high compensation mode; the advantage of this circuit is that the system detects the incoming line all the time Voltage, if any operating condition is met, the low-voltage compensation and voltage regulation device will quickly switch the circuit to the corresponding control mode by issuing instructions. The device turns the circuit into bypass mode, disconnects the normally open contact of the single-pole double-throw magnetic latching relay KA1, closes the normally closed contact, switches the circuit cycle, and makes dynamic compensation to adjust the voltage value of the outgoing line to ensure that the outgoing line is connected. Stability of load power consumption.

Embodiment 2: Referring to FIG. 3, a switch connection circuit suitable for a low-voltage compensation voltage regulating device in embodiment 2 utilizes a compensation transformer T with 7 taps and two groups of four single-pole double-throw magnetic latching relays KA1, KA2, KA3 Cooperating with KA4, five compensation modes can be realized, which are bypass mode, low compensation mode, high compensation mode, low step-down mode and high step-down mode. The magnetic latching relay, that is, the single-pole double-throw magnetic latching relay changes the taps on the primary side of a compensation transformer with taps to achieve step-up and step-down actions.

Referring to Fig. 3 and Fig. 4, a switch connection circuit applicable to a low-voltage compensation voltage regulating device in Embodiment 2 is divided into five working modes, which are respectively defined as bypass mode, low compensation mode, high compensation mode, and low step-down mode And the high step-down mode, which are applicable to five different on-site working conditions. There are two situations in the bypass mode. One is suitable for the compensation control system of the circuit to detect that the incoming line voltage of the circuit meets the power supply standard voltage requirement of the load side. , without compensation, switching is bypass mode; secondly, the compensation control system suitable for this circuit detects that the incoming line voltage of the circuit exceeds (lower or higher than) the operating conditions of the low-voltage compensation and voltage regulating device and cannot be compensated, then Switching is bypass mode; low compensation mode is suitable for the compensation control system of this circuit. When the incoming line voltage is detected to be in a slight undervoltage state and does not meet the load operation, the system will switch the circuit to low compensation mode; high compensation mode is applicable If the compensation control system detects that the incoming line voltage is seriously under-voltage, which does not satisfy the load operation at all, the circuit will be switched to the high compensation mode; the low step-down mode is suitable for the circuit. In the slight overvoltage state, the system will switch the circuit to the low step-down mode; the high step-down mode applies to the compensation control system of the circuit and detects that the incoming line voltage is in a serious overvoltage state, then the system will switch the circuit to the high step-down mode .

Bypass mode: The ① and ② normally closed contacts of the single-pole double-throw magnetic latching relay KA1 are closed, and the incoming line directly forms a path with the outgoing line without going through a compensation transformer T with a tap for voltage compensation. At this time, because the ③ and ① of the single-pole double-throw magnetic latching relay KA1 are in the disconnected state, the single-pole double-throw magnetic latching relay KA2 does not work.

Low compensation mode: The ① and ③ normally open contacts of the SPDT magnetic latching relay KA1 are closed, the incoming line is connected to the ⑤ tap of a compensation transformer T with taps, and passes through the ① and ③ of the SPDT magnetic latching relay KA1 Connect point ① of the single-pole double-throw magnetic latching relay KA2 with point ③ of the single-pole double-throw magnetic latching relay KA1. At this time, the single-pole double-throw magnetic latching relay KA2 is a relay that selects two modes of boost and buck. ① and ② of SPDT magnetic latching relay KA2 are closed, and the circuit enters boost mode. At this time, SPDT magnetic latching relay KA3 is the selection relay for determining low compensation mode and high compensation mode. If SPDT magnetic latching relay KA3 Points ① and ② are closed, then the incoming line is connected to tap ① of a compensation transformer T with taps through SPDT magnetic latching relays KA1, KA2 and KA3, and a compensation transformer T with taps works in low compensation mode. The outgoing line voltage is the compensation voltage of the primary side, which is electromagnetically induced to a voltage on the secondary side and added to the intrinsic line voltage value of the secondary side at the same time.

High compensation mode: ① and ③ of the single-pole, double-throw magnetic latching relay KA1 are closed, and the incoming line is connected to the ⑤ tap of a compensation transformer with taps, and the ① and ③ of the single-pole, double-throw magnetic latching relay KA1 are connected to each other. Point ① of the single-pole double-throw magnetic latching relay KA2 is connected to ③ of the single-pole double-throw magnetic latching relay KA1. At this time, the single-pole double-throw magnetic latching relay KA2 is a relay that selects two modes of boost and buck. ① and ② of SPDT magnetic latching relay KA2 are closed, and the circuit enters boost mode. At this time, SPDT magnetic latching relay KA3 is the selection relay for determining low compensation mode and high compensation mode. If SPDT magnetic latching relay KA3 Points ① and ③ are closed, then the incoming line is connected to tap ② of a compensation transformer T with taps through single pole double throw magnetic latching relays KA1, KA2 and KA3, and a compensation transformer T with taps works in high compensation mode. The outgoing line voltage is the compensation voltage of the primary side, which is electromagnetically induced to a voltage on the secondary side and added to the intrinsic line voltage value of the secondary side at the same time.

Low step-down mode: The ① and ③ normally open contacts of the SPDT magnetic latching relay KA1 are closed, the incoming line is connected to the ⑤ tap of a compensation transformer T with taps, and passes through the ① and ③ of the SPDT magnetic latching relay KA1. ③ Connect point ① of the single-pole, double-throw magnetic latching relay KA2 with point ③ of the single-pole, double-throw magnetic latching relay KA1. At this time, the single-pole double-throw magnetic latching relay KA2 is a relay that selects two modes of boost and buck. ① and ③ of SPDT magnetic latching relay KA2 are closed, and the circuit enters step-down mode. At this time, SPDT magnetic latching relay KA4 is the selection relay for determining low step-down mode and high step-down mode. The ① and ③ points of the relay KA4 are closed, and the incoming line is connected to the ④ tap of a compensation transformer T with a tap through the single-pole double-throw magnetic latching relays KA1, KA2 and KA4, and a compensation transformer T with a tap works in a low step-down mode . The outgoing line voltage is the compensation voltage of the primary side through electromagnetic induction to a voltage of the secondary side and subtracted from the intrinsic line voltage value of the secondary side at the same time.

High step-down mode: The ① and ③ normally open contacts of the single-pole double-throw magnetic latching relay KA1 are closed. ③ Connect point ① of the single-pole, double-throw magnetic latching relay KA2 with point ③ of the single-pole, double-throw magnetic latching relay KA1. At this time, the single-pole double-throw magnetic latching relay KA2 is a relay that selects two modes of boost and buck. ① and ③ of SPDT magnetic latching relay KA2 are closed, and the circuit enters step-down mode. At this time, SPDT magnetic latching relay KA4 is the selection relay for determining low step-down mode and high step-down mode. Points ① and ② of relay KA4 are closed, and the incoming line is connected to tap ③ of a compensating transformer T with taps through SPDT magnetic latching relays KA1, KA2, and KA4, and a compensating transformer T with taps works in high step-down mode . The outgoing line voltage is the compensation voltage of the primary side through electromagnetic induction to a voltage of the secondary side and subtracted from the intrinsic line voltage value of the secondary side at the same time.

Switch from low compensation mode to high compensation mode: only need to keep SPDT latching relays KA1 and KA2 in boost state, disconnect contacts ① and ③ of SPDT latching relay KA3, and switch to SPDT latching relay KA1 and KA2. Keep contacts ① and ② of relay KA3 closed, and vice versa.

Switch from low voltage drop mode to high voltage drop mode: only need to keep SPDT latching relays KA1 and KA2 in step-down state, disconnect contacts ① and ③ of SPDT latching relay KA4, and switch to SPDT The ① and ② contacts of the throw magnetic holding relay KA4 are closed, and vice versa.

The circuit can drive the magnetic latching relay with changeover contact structure through the low-voltage compensation voltage regulating device, that is, the action of the single-pole double-throw magnetic latching relay, and in the bypass mode, low compensation mode, high compensation mode, low step-down mode and high The switching between the five working modes of the mode is mutual, and the timing is strictly maintained for each action. The magnetic latching relay with a changeover contact structure in the design is within half a cycle of the mains waveform from the switching action to the end of the action. It will not cause any interference and influence on the output voltage, and the circuit design forms a switch lock mode, no short circuit will occur under any circumstances, and it has extremely high safety and reliability. It adopts a magnetic latch with a conversion contact structure The relay only consumes electric energy when it is in action. After the action is completed, the internal mechanical structure maintains the current state and does not consume energy, so the power consumption of the circuit is low.

A switch connection circuit suitable for a low-voltage compensation and voltage regulating device of the utility model can also be expanded, and more single-pole double-throw magnetic latching relays are used to switch the taps of a corresponding compensation transformer with taps to achieve more Multiple compensation modes.

The utility model relates to a switch connection circuit suitable for a low-voltage compensation voltage regulating device, and the inventive technical solution lies in the composition of the switch connection circuit. The software program involved belongs to the prior art, and the software program is programmed according to C language, which is a technology familiar to those skilled in the art, and is not a technical solution of the utility model.

The above embodiments are only used to illustrate the technical solutions of the present utility model, and are not intended to limit it; although the utility model has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: it can still be applied to the foregoing embodiments Modifications are made to the recorded technical solutions, or equivalent replacements are made to some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present utility model.

Claims (1)

1. A switch connection circuit suitable for low-voltage compensating and voltage regulating devices, which includes a compensation transformer with a tap, is characterized in that it also includes at least one group of magnetic latching relays with a changeover contact structure, and the described one has a changeover contact structure The magnetic latching relay is connected to a compensation transformer with taps.