Frequency converter output overcurrent protection circuit based on NSM2015 and frequency converter
Through the inverter output overcurrent protection circuit based on the NSM2015 chip, the problem of many devices and high costs in the prior art is solved, effective protection of the inverter output overcurrent and circuit simplification is realized, and power consumption and cost are reduced.
Patent Information
- Application Number
- CN202422198911.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-06
- Publication Date
- 2025-06-27
- Estimated Expiration
- 2034-09-06
AI Technical Summary
The existing inverter output overcurrent protection methods have problems such as many devices and high costs, especially in small-power inverters.
The inverter output overcurrent protection circuit based on the NSM2015 chip is adopted, and the inverter output overcurrent protection circuit is protected by the combination of chip U1, resistor, capacitor, transistor and other components.
While ensuring the effective overcurrent protection of the inverter output, the circuit structure is simplified, the device power consumption is reduced, the service life is extended, and the cost is reduced.
Smart Images
Figure CN223039633U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of frequency converters, in particular to an overcurrent protection circuit for the output of a frequency converter based on NSM2015 and a frequency converter. Background Art
[0002] Most of the conventional methods for overcurrent protection of the output of a frequency converter are realized by using resistors or Hall detection. Among them, for the Hall detection scheme, in addition to the Hall chip itself, quite a few components are required for cooperation, resulting in problems such as many devices and high costs, and it has no advantage in the application of small-power frequency converters.
[0003] Therefore, there are defects in the prior art and improvement is needed. Summary of the Utility Model
[0004] The purpose of the utility model is to overcome the deficiencies of the prior art and provide an overcurrent protection circuit for the output of a frequency converter based on NSM2015 and a frequency converter.
[0005] The technical solution of the utility model is as follows: The utility model provides an overcurrent protection circuit for the output of a frequency converter based on NSM2015, including: chip U1, resistor R1, resistor R2, resistor R3, resistor R4, resistor R5, resistor R6, capacitor C1, capacitor C2, capacitor C3, triode Q1. The model of the chip U1 is NSM2015, and the triode is a PNP triode. The chip U1 is electrically connected to the drive circuit of the motor for current acquisition. The Fault pin of the chip U1 is electrically connected to one end of the resistor R1. The other end of the resistor R1 is respectively electrically connected to one end of the resistor R2, one end of the resistor R5, and one end of the capacitor C1. The other end of the resistor R2 is electrically connected to the VCC terminal. The other end of the capacitor C1 is grounded. The other end of the resistor R5 is electrically connected to the base of the triode. The collector of the triode is grounded. The emitter of the triode is respectively electrically connected to one end of the resistor R6 and the drive blocking circuit of the frequency converter. The other end of the resistor R6 is electrically connected to the VCC terminal. The VCC pin of the chip U1 is respectively electrically connected to one end of the capacitor C2 and the VCC terminal. The other end of the capacitor C2 is grounded. The VOC terminal of the chip U1 is respectively electrically connected to one end of the resistor R3 and one end of the resistor R4. The other end of the resistor R3 is grounded. The VREF pin of the chip U1 is respectively electrically connected to the other end of the resistor R4 and one end of the capacitor C3. The other end of the capacitor C3 is grounded. The GND terminal of the chip U1 is grounded.
[0006] The utility model also provides a frequency converter, including the above-mentioned overcurrent protection circuit for the output of a frequency converter based on NSM2015.
[0007] With the above solution, the beneficial effects of the present utility model are as follows: while ensuring the effectiveness of the over-current protection of the frequency converter output, the circuit is simplified. The NSM2015 chip also has the characteristics of fast response speed and extremely low on-resistance, which can effectively reduce the power consumption of circuit devices and increase the service life. Brief Description of the Drawings
[0008] Figure 1 It is a circuit diagram of the over-current protection circuit of the present utility model. Specific Embodiments
[0009] The present utility model will be described in detail below with reference to the accompanying drawings and specific embodiments.
[0010] Please refer to Figure 1In this embodiment, the utility model provides an inverter output overcurrent protection circuit based on NSM2015, including: chip U1, resistor R1, resistor R2, resistor R3, resistor R4, resistor R5, resistor R6, capacitor C1, capacitor C2, capacitor C3, transistor Q1, the model of the chip U1 is NSM2015, the transistor is a PNP transistor, the chip U1 is electrically connected to the motor drive circuit for current collection, specifically through the IP1+ pin, IP2+ pin, IP3+ pin, IP4+ pin, and IP1- pin, IP2- pin, IP3- pin, IP4- pin of the chip U1 to achieve connection into the drive circuit. The Fault pin of the chip U1 is electrically connected to one end of the resistor R1, and the other end of the resistor R1 is electrically connected to one end of the resistor R2, one end of the resistor R5, and one end of the capacitor C1, respectively. The capacitor C1 plays the role of energy storage filtering in the circuit to prevent the signal from being interfered. The resistor R1 is a freewheeling resistor. The other end of the resistor R2 is electrically connected to the VCC terminal, and the resistor R2 is a pull-up resistor. The other end of the capacitor C1 is grounded, and the other end of the resistor R5 is electrically connected to the base of the transistor, and the resistor R5 serves as the base input resistor of the transistor Q1. The collector of the transistor is grounded, and the emitter of the transistor is electrically connected to one end of the resistor R6 and the inverter drive blocking circuit OI terminal respectively, and the transistor Q1 is used to switch the high and low level states of the OI signal. The other end of the resistor R6 is electrically connected to the VCC terminal, and the resistor R6 serves as a load resistor in the circuit, bearing part of the energy consumption and limiting the collector current to protect the transistor Q1. The VCC pin of the chip U1 is electrically connected to one end and the VCC end of the capacitor C2, respectively. The other end of the capacitor C2 is grounded. The VOC end of the chip U1 is electrically connected to one end and one end of the resistor R3, respectively. The other end of the resistor R3 is grounded. The VREF pin of the chip U1 is electrically connected to the other end of the resistor R4 and one end of the capacitor C3, respectively. The resistors R3 and R4 are voltage divider resistors used to determine the overcurrent threshold. The other end of the capacitor C3 is grounded, and the GND end of the chip U1 is grounded. The capacitors C2 and C3 are used as bypass capacitors to improve the power supply's anti-interference capability. Among them,
[0011] In this solution, when the frequency converter is operating normally, the absolute value of the primary current of the chip U1 is less than the set current threshold, Fault is cleared, the triode Q1 is cut off, the OI terminal is in a high-level state, the frequency converter drive blocking circuit is ineffective, and the frequency converter operates normally. When an overcurrent phenomenon occurs in the frequency converter, the current passes through the chip U1. At this time, the primary current exceeds the set overcurrent threshold, and the internal error comparator of the chip U1 is reversed, and the drive OD output works, causing the Fault pin to be pulled low, the triode Q1 to conduct, and the OI terminal level to be low, making the frequency converter drive blocking circuit effective, thereby blocking the drive and realizing the protection of the inverter unit of the frequency converter. When the current signal is disconnected, there is no output at the Fault pin, the base voltage of the triode Q1 is pulled to VCC by the resistor R2, the triode Q1 is cut off, and the OI remains in a high-level state, which will not cause misoperation.
[0012] The present utility model also provides a frequency converter, including the above-mentioned overcurrent protection circuit for the frequency converter output based on NSM2015, so that the overcurrent protection circuit of the frequency converter has a simplified circuit and has the advantages of low cost, low power consumption, and long service life.
[0013] In summary, the beneficial effects of this solution are as follows: while ensuring the effectiveness of the overcurrent protection of the frequency converter output, the circuit is simplified. The NSM2015 chip also has the characteristics of fast response speed and extremely low on-resistance, which can effectively reduce the power consumption of circuit devices and increase the service life.
[0014] The above are only the preferred embodiments of the present utility model and are not used to limit the present utility model. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present utility model shall be included in the protection scope of the present utility model.
Claims
1. An inverter output overcurrent protection circuit based on NSM2015, characterized in that: include: Chip U1, resistor R1, resistor R2, resistor R3, resistor R4, resistor R5, resistor R6, capacitor C1, capacitor C2, capacitor C3, transistor Q1, the model of the chip U1 is NSM2015, the transistor is a PNP transistor, the chip U1 is electrically connected to the drive circuit of the motor for current collection, the Fault pin of the chip U1 is electrically connected to one end of the resistor R1, the other end of the resistor R1 is electrically connected to one end of the resistor R2, one end of the resistor R5, and one end of the capacitor C1, the other end of the resistor R2 is electrically connected to the VCC terminal, the other end of the capacitor C1 is grounded, and the other end of the resistor R5 is connected to the base of the transistor. The transistor is electrically connected to the VCC terminal, the collector of the transistor is grounded, the emitter of the transistor is electrically connected to one end of the resistor R6 and the inverter drive blocking circuit respectively, the other end of the resistor R6 is electrically connected to the VCC terminal, the VCC pin of the chip U1 is electrically connected to one end and the VCC terminal of the capacitor C2 respectively, the other end of the capacitor C2 is grounded, the VOC terminal of the chip U1 is electrically connected to one end of the resistor R3 and one end of the resistor R4 respectively, the other end of the resistor R3 is grounded, the VREF pin of the chip U1 is electrically connected to the other end of the resistor R4 and one end of the capacitor C3 respectively, the other end of the capacitor C3 is grounded, and the GND terminal of the chip U1 is grounded.
2. A frequency converter, characterized in that: It includes the inverter output overcurrent protection circuit based on NSM2015 as claimed in claim 1.