Inverter structure

Abstract

The utility model provides an inverter structure which comprises a control circuit, and the control circuit is provided with an inverter component and a control switch K used for controlling the output or closing of the inverter component. The comparison circuit is connected with the control circuit so as to receive the current on the control circuit; the protection circuit is in signal connection with the control circuit; the comparison circuit outputs a signal to the protection circuit according to the received current on the control circuit; and the protection circuit controls the control switch K to be switched on or switched off according to the signal output by the comparison circuit. The inverter structure provided by the utility model solves the technical problem that the inverter is easy to damage.

Description

Technical Field

[0001] This utility model relates to the field of inverter technology, and specifically to an inverter structure. Background Technology

[0002] Currently, commercial air conditioning products are widely adopting frequency conversion, and the reliability of frequency conversion drive technology is receiving increasing attention. Three-phase commercial air conditioners have higher power and generally higher current, which makes them prone to current overshoot under harsh or unavoidable conditions. This can easily damage the drive board and increase customer and after-sales maintenance costs. Therefore, overcurrent protection has become the most important part of current drive control.

[0003] However, traditional overcurrent protection methods involve sampling a large current and then shutting down the PWM output of the DSP to achieve overcurrent protection. This method lacks a direct shutdown circuit, resulting in a slow response time and a higher risk of damaging the circuit.

[0004] Therefore, existing technologies need further development. Utility Model Content

[0005] The purpose of this invention is to overcome the above-mentioned technical deficiencies and provide an inverter structure to solve the technical problem of inverters being easily damaged in related technologies.

[0006] To achieve the above technical objectives, the present invention adopts the following technical solution: It provides an inverter structure, comprising: a control circuit, on which an inverter component and a control switch K1 for controlling the output or shutdown of the inverter component are disposed; a comparator circuit, connected to the control circuit to receive current from the control circuit; and a protection circuit, signal-connected to the control circuit; the comparator circuit outputs a signal to the protection circuit based on the received current from the control circuit; and the protection circuit controls the control switch K1 to close or open based on the signal output by the comparator circuit.

[0007] Furthermore, the control circuit includes: a P-phase circuit connected to the inverter component; an N-phase circuit connected to the inverter component; a comparator circuit connected to the N-phase circuit; a connection circuit, one end of which is connected to the P-phase circuit and the other end of which is connected to the N-phase circuit; and a capacitor is provided on the connection circuit.

[0008] Furthermore, there are multiple capacitors connected in series; and / or, the protection circuit is connected to the P-phase circuit; and / or, an inductor L is provided on the P-phase circuit; the inductor L is located upstream of the connection circuit.

[0009] Furthermore, the comparison circuit includes: a current sensor located downstream of the connection circuit; the current sensor is disposed on the N-phase circuit; a comparator connected to the current sensor; and the comparator outputs a comparison signal based on the current transmitted by the current sensor.

[0010] Furthermore, the comparator circuit includes: capacitor C3, one end of which is connected to the circuit between the current sensor and the comparator, and the other end of which is grounded.

[0011] Furthermore, the comparator circuit includes a 555 timer, which is connected to the output of the comparator. The 555 timer sends the comparison signal output by the comparator to the protection circuit.

[0012] Furthermore, the protection circuit includes: a drive circuit for controlling the switch K1 to close or open; and a drive module connected to the drive circuit to control the on / off state of the drive circuit according to the comparison signal.

[0013] Furthermore, the driving circuit includes: a MOSFET, the gate of which is connected to the driving module; the source of which is connected to the control circuit; and the drain of which is connected to the driving circuit.

[0014] Furthermore, the driving module includes: a transistor, the base of which is connected to the comparator circuit; and the emitter of which is connected to the gate of the MOSFET.

[0015] Furthermore, the inverter structure also includes: resistors R3 and R4, which are connected in series with the emitter of the transistor, and the circuit between resistors R3 and R4 is connected to the gate of the MOSFET; and capacitor C2, which is connected in parallel with resistor R4.

[0016] Furthermore, the inverter structure also includes: a resistor R1 connected in series with the gate of the MOSFET; a resistor R2 connected in series with the drain of the MOSFET; a circuit connection between the drive circuit and the resistor R2 and the drain of the MOSFET; and a capacitor C1 connected in parallel with the resistor R2.

[0017] Beneficial effects:

[0018] The inverter structure of this utility model includes a control circuit, on which an inverter component and a control switch K for controlling the output or shutdown of the inverter component are mounted; a comparator circuit, connected to the control circuit to receive the current from the control circuit; and a protection circuit, signal-connected to the control circuit. The comparator circuit outputs a signal to the protection circuit based on the received current from the control circuit; the protection circuit controls the control switch K to close or open based on the signal output by the comparator circuit. With the above configuration, the connection between the power supply side and the inverter side can be directly disconnected through the overcurrent protection circuit, protecting both the inverter module and the compressor side. Both provide overcurrent protection, achieving a faster and more efficient response to overcurrent protection. Responding to overcurrent protection through hardware means (relay K shutdown control) is faster and more efficient than traditional software-based sampling control, solving the technical problem of inverters being easily damaged. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the inverter structure under overcurrent conditions used in this embodiment of the utility model;

[0020] Figure 2 This is a schematic diagram of the inverter structure used in this embodiment of the present invention during normal operation.

[0021] Figure 3 This is a flowchart illustrating the operation of the inverter structure used in this embodiment of the utility model.

[0022] Figure 4 This is a schematic diagram of the current flow direction during overcurrent in the inverter structure used in this embodiment of the utility model;

[0023] Figure 5 This is a schematic diagram of the current flow direction of the inverter component when the inverter structure used in this embodiment of the utility model is working.

[0024] The above figures include the following reference numerals:

[0025] 1. Control circuit; 11. P-phase circuit; 12. N-phase circuit; 13. Connection circuit; 2. Inverter components; 3. Comparison circuit; 31. Current sensor; 32. Comparator; 33. 555 timer; 4. Protection circuit; 41. Drive circuit; 42. Drive module. Detailed Implementation

[0026] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of protection of the present application.

[0027] See Figures 1 to 5 According to an embodiment of this utility model, an inverter structure is provided, including: a control circuit 1, on which an inverter component 2 and a control switch K1 for controlling the output or shutdown of the inverter component 2 are disposed; a comparator circuit 3, connected to the control circuit 1 to receive the current on the control circuit 1; and a protection circuit 4, signal-connected to the control circuit 1. The comparator circuit 3 outputs a signal to the protection circuit 4 based on the received current on the control circuit 1. The protection circuit 4 controls the control switch K1 to close or open based on the signal output by the comparator circuit 3. With the above configuration, the connection between the power supply side and the inverter side can be directly disconnected through the protection circuit 4, protecting both the inverter module and the compressor side. Both provide overcurrent protection, achieving a faster and more efficient response to overcurrent protection. Responding to overcurrent protection through hardware means (relay K1 shutdown control) is faster and more efficient than traditional software-based sampling control, solving the technical problem of inverters being easily damaged.

[0028] In the inverter structure of this embodiment, see Figure 1 , Figure 2 The control circuit 1 includes: a P-phase circuit 11 connected to the inverter component 2; an N-phase circuit 12 connected to the inverter component 2; a comparator circuit 3 connected to the N-phase circuit 12; and a connection circuit 13, one end of which is connected to the P-phase circuit 11, and the other end of which is connected to the N-phase circuit 12. A capacitor is provided on the connection circuit 13. In this way, by providing a capacitor, the AC current in the control circuit 1 passes through the capacitor, thereby acting as a filter and facilitating the signal generation by the comparator circuit 3.

[0029] See Figure 1 , Figure 2 In the inverter structure of this embodiment, there are multiple capacitors connected in series; this helps to improve the filtering effect.

[0030] Protection circuit 4 is connected to P-phase circuit 11. In the inverter structure of this embodiment, see [link to relevant documentation]. Figure 1 , Figure 2 In this way, the protection circuit 4 is powered by the control circuit 1, which simplifies the circuit structure.

[0031] See Figure 1 , Figure 2 An inductor L is provided on the P-phase circuit 11; the inductor L is located upstream of the connection circuit 13.

[0032] See Figure 1 , Figure 2 In the inverter structure of this embodiment, the comparator circuit 3 includes: a current sensor 31, located downstream of the connection circuit 13; the current sensor 31 is disposed on the N-phase circuit 12; and a comparator 32 connected to the current sensor 31. The comparator 32 outputs a comparison signal based on the current transmitted by the current sensor 31. Thus, the current passes through the current sensor 31 and outputs a corresponding voltage value. The comparator determines whether there is an overcurrent based on the corresponding voltage value output by the current sensor 31, thereby outputting different signals.

[0033] In the inverter structure of this embodiment, see Figure 1 , Figure 2 The comparator circuit 3 includes a capacitor C3, one end of which is connected to the circuit between the current sensor 31 and the comparator 32, and the other end of which is grounded. This filters the signal input to the comparator 32, ensuring the accuracy of the input signal.

[0034] See Figure 1 , Figure 2 In the inverter structure of this embodiment, the comparator circuit 3 includes a 555 timer 33, which is connected to the output of the comparator 32. The 555 timer 33 sends the comparison signal output by the comparator to the protection circuit 4. Thus, the function of the 555 timer is to keep FO at a low level for a period of time when an overcurrent is triggered, ensuring that the capacitor is fully discharged within this period.

[0035] In the inverter structure of this embodiment, see Figure 1 , Figure 2 The protection circuit 4 includes: a drive circuit 41, which controls the closing or opening of switch K1; and a drive module 42, which is connected to the drive circuit 41 to control the on / off state of the drive circuit 41 according to a comparison signal. In this way, a single signal can be converted into the action of the control switch K1, thereby making the control faster.

[0036] See Figure 1 , Figure 2 In the inverter structure of this embodiment, the drive circuit 41 includes a MOSFET, the gate of which is connected to the drive module 42; the source of which is connected to the control circuit 1; and the drain of which is connected to the drive circuit 41. Thus, by using a comparison signal, the power supply to the drive circuit 41 can be controlled to be either on or off, thereby controlling whether the switch is open.

[0037] In the inverter structure of this embodiment, see Figure 1 , Figure 2 The driving module 42 includes a transistor, the base of which is connected to the comparator circuit 3; and the emitter of which is connected to the gate of the MOSFET. By setting the transistor, the type of signal transmitted from the comparator circuit 2 is determined, thereby triggering the transistor to be energized or de-energized, and thus controlling whether switch K1 is open.

[0038] See Figure 1 , Figure 2 In the inverter structure of this embodiment, the inverter structure further includes: resistors R3 and R4, which are connected in series with the emitter of the transistor, and the circuit between resistors R3 and R4 is connected to the gate of the MOSFET; and capacitor C2, which is connected in parallel with resistor R4. Thus, the voltage division of resistors R3 and R4 provides a suitable signal to the MOSFET.

[0039] In the inverter structure of this embodiment, see Figure 1 , Figure 2 The inverter structure also includes: a resistor R1 connected in series with the gate of the MOSFET; a resistor R2 connected in series with the drain of the MOSFET; a circuit connection between the drive circuit 41 and the resistor R2 and the drain of the MOSFET; and a capacitor C1 connected in parallel with the resistor R2. In this way, the resistors R1 and R2 divide the voltage, providing a suitable voltage to the drive circuit 41, thereby precisely controlling the switch K1.

[0040] Example 1:

[0041] When the driver board is operating normally and the current protection value is not exceeded, the current is output through the current sensor 31 to output the corresponding voltage value. At this time, when the output voltage value is less than the set reference voltage protection value U2, the desired set value is obtained through voltage division by resistors R5 and R6, i.e., U0 < U2. The comparator outputs a high-level signal, and then the 555 timer outputs a high-level signal. At this time, FO is at a high level, transistor Q1 is turned on, and capacitor C2 is charged. According to the voltage division of R3 and R4, U1 obtains a conduction voltage drop, which turns on the MOSFET. The DC bus P obtains a voltage of about 12V through voltage division of R1 and R2, which drives the relay K1 to engage, and the driver board operates normally.

[0042] When a large current occurs during operation, the current sensor outputs a corresponding voltage value. If this output voltage value is greater than the set reference voltage protection value U2 (i.e., U0 > U2), a low-level signal is output by the comparator, and then by the 555 timer. At this point, FO is a low-level signal, transistor Q1 is cut off, the MOSFET is turned off, capacitor C1 discharges instantaneously through R2, and the voltage across capacitor C1 drops to 0. No current flows through relay K1, the relay disconnects, and the circuit is broken, achieving the purpose of overcurrent protection. This overcurrent protection method not only ensures rapid protection for the inverter module side, but also provides rapid response protection for the power supply side the instant K1 disconnects.

[0043] The 555 timer is used here to trigger an overcurrent event, causing FO to remain at a low level for a period of time, ensuring that the capacitor is fully discharged within this period.

[0044] When the driver board is running normally, that is, when transistor Q1 and MOSFET are turned on, resistor R4 acts as a voltage divider resistor, which plays a role in voltage division. When an overcurrent is triggered, R4 acts as a discharge resistor, which plays a role in quickly discharging capacitor C2, which is one of the means of faster response protection.

[0045] Example 2:

[0046] In the inverter structure of this embodiment, see Figure 4 When the inverter structure is working normally, switch K1 is closed, and the current flows from control circuit 1 through inverter component 2 to power inverter component 2, ensuring that inverter component 2 works normally.

[0047] Example 3:

[0048] In the inverter structure of this embodiment, see Figure 4 When the inverter structure is working normally, switch K1 is closed, and the current flows from control circuit 1 through comparator circuit 3 to provide a reference voltage value for comparator circuit 3. Comparator circuit 3 compares the voltage value. If the current is normal, it outputs a signal to drive protection circuit 3 to keep switch K1 open.

[0049] When the inverter structure experiences an overcurrent, the current flows from the control circuit 1 through the comparator circuit 3, providing a reference voltage value for the comparator circuit 3. The comparator circuit 3 compares the voltage value and outputs a signal to drive the protection circuit 3 to disconnect switch K1, providing protection.

[0050] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0051] Optionally, specific examples in this embodiment can refer to the examples described in the above embodiments, and will not be repeated here.

[0052] The sequence numbers of the embodiments in this application are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0053] In the above embodiments of this application, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0054] The above description is only a preferred embodiment of this application. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of this application, and these improvements and modifications should also be considered within the scope of protection of this application.

Claims

1. An inverter structure, characterized by comprising: The application relates to an inverter structure, comprising: a control circuit (1) provided with an inverter component (2) and a control switch K1 for controlling the output or shutdown of the inverter component (2); a comparison circuit (3) connected with the control circuit (1) to receive the current on the control circuit (1); a protection circuit (4) connected with the control circuit (1) in signal mode; the comparison circuit (3) outputs a signal to the protection circuit (4) according to the received current on the control circuit (1); the protection circuit (4) controls the control switch K1 to be closed or opened according to the signal output by the comparison circuit (3); the control circuit (1) comprises: a P-phase circuit (11) connected with the inverter component (2); an N-phase circuit (12) connected with the inverter component (2); the comparison circuit (3) is connected with the N-phase circuit (12); a connecting circuit (13) having one end connected with the P-phase circuit (11) and the other end connected with the N-phase circuit (12); and a capacitor arranged on the connecting circuit (13).

2. The inverter structure according to claim 1, wherein: the capacitor is a plurality of capacitors connected in series; and / or the protection circuit (4) is connected with the P-phase circuit (11); and / or an inductor L is arranged on the P-phase circuit (11) and located upstream of the connecting circuit (13). The comparison circuit (3) comprises: a current sensor (31) located downstream of the connecting circuit (13) and arranged on the N-phase circuit (12); and a comparator (32) connected with the current sensor (31) and outputting a comparison signal according to the current transmitted by the current sensor (31). The comparison circuit (3) comprises: a capacitor C3 having one end connected to a circuit between the current sensor (31) and the comparator (32) and the other end grounded. The comparison circuit (3) comprises a 555 timer (33) connected with the output end of the comparator (32) and sending the comparison signal output by the comparator to the protection circuit (4). The protection circuit (4) comprises: a driving circuit (41) for controlling the control switch K1 to be closed or opened; and a driving module (42) connected with the driving circuit (41) to control the on-off of the driving circuit (41) according to the comparison signal. The driving circuit (41) comprises: a MOS tube having a gate connected with the driving module (42), a source connected with the control circuit (1) and a drain connected with the driving circuit (41). The driving module (42) comprises: ​ ​ ​ ​ 3. The inverter structure of claim 2, wherein, ​ ​ ​ 4. The inverter structure of claim 3, wherein, ​ ​ 5. The inverter structure of claim 4, wherein, ​ 6. The inverter structure of claim 3, wherein, ​ ​ ​ 7. The inverter structure of claim 6, wherein, ​ ​ 8. The inverter structure of claim 7, wherein, ​ A triode, a base of the triode is connected with the comparison circuit (3); an emitter of the triode is connected with the gate of the MOS tube.

9. The inverter structure of claim 8, wherein, The inverter structure further comprises: A resistor R3 and a resistor R4, the resistor R3 and the resistor R4 are connected in series with the emitter of the triode in turn, a circuit between the resistor R3 and the resistor R4 is connected with the gate of the MOS tube; A capacitor C2, which is connected with the resistor R4 in parallel.

10. The inverter structure of claim 8, wherein, The inverter structure further comprises: A resistor R1, which is connected with the gate of the MOS tube in series; A resistor R2, which is connected with the drain of the MOS tube in series; the driving circuit (41) is connected with a circuit between the resistor R2 and the drain of the MOS tube; A capacitor C1, which is connected with the resistor R2 in parallel.

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