Reactor precision control circuit based on load box

Abstract

The utility model discloses an electric reactor precision control circuit based on a load box, and belongs to the technical field of load boxes. The device mainly comprises a control circuit used for controlling a reactor, the control circuit comprises an MCU and a PWM control circuit, the control output end of the PWM control circuit is electrically connected with the switch control end of a drive circuit, and the power supply end of the drive circuit is electrically connected with a power supply module through a protection circuit. The power supply output end of the driving circuit is electrically connected with the power supply end of the electric reactor, the detection end of the feedback sensor detects an electric signal between the electric reactor and a load, the PWM frequency and the duty ratio are adjusted through the PWM control circuit to control on and off of an MOS tube Q1 in the driving circuit, and therefore power supply to the electric reactor is controlled. And voltage and current detection is carried out on a line from the reactor to a load through a current sensor and a voltage sensor in the feedback sensor, so that turn-off of the reactor by the driving circuit is controlled by controlling the PWM control circuit, and the reactor can be accurately controlled.

Description

Technical Field

[0001] The present application relates to the technical field of load boxes, and in particular to a reactor precision control circuit based on a load box. Background Art

[0002] A load bank is a device used to test and simulate the performance of electrical equipment (such as generators, transformers, inverters, etc.) under different load conditions. Its main function is to provide an adjustable load to evaluate the output characteristics and stability of the equipment during experiments or tests.

[0003] A search revealed the publication number CN216597250U, which discloses a reactor comprising an upper iron yoke and a lower iron yoke, with an iron core leg disposed between the upper and lower iron yokes. A coil is wound around the core leg, and a temperature controller is disposed between the core leg and the coil. The temperature controller is connected to the reactor circuit to monitor the reactor's temperature. When the temperature exceeds a set value, the temperature controller automatically disconnects the reactor circuit; when the temperature falls below the set value, the temperature controller automatically connects the reactor circuit, thereby achieving temperature control of the reactor.

[0004] However, although in the prior art, a temperature control protector is added to the reactor to ensure that the reactor operates in a reasonable operating temperature environment, during the control process of the reactor, if the current and voltage between the reactor and the load are too high or too low, the reactor and the load may be damaged, which still needs to be solved. The reactor needs to be precisely controlled and disconnected to avoid overcurrent and overvoltage.

[0005] Therefore, it is necessary to provide a load box-based reactor precision control circuit to solve the above problems.

[0006] It should be noted that the above information disclosed in this Background section is only for understanding the background technology of the present application concept, and therefore, it may contain information that does not constitute prior art. Utility Model Content

[0007] The purpose of the utility model is to provide a reactor precision control circuit based on a load box to solve the problems raised in the above background technology.

[0008] The technical solution adopted by this application to solve its technical problems is:

[0009] A load box-based reactor precision control circuit includes a control circuit for controlling the reactor, the control circuit including an MCU and a PWM control circuit, a control output end of the PWM control circuit electrically connected to a switch control end of a drive circuit, a power supply end of the drive circuit electrically connected to a power supply module via a protection circuit, a power supply output end of the drive circuit electrically connected to a power supply end of the reactor, the reactor electrically connected to a load via a line, a detection end of a feedback sensor detecting an electrical signal from the reactor to the load, and a signal output end of the feedback sensor electrically connected to a signal receiving end of the MCU.

[0010] Preferably, the PWM control circuit includes a main control chip U1, wherein the VCC terminal and the RST terminal of the main control chip U1 are electrically connected to the power supply terminal of the power supply module, and are also connected to one end of the resistor R1, the other end of the resistor R1 is connected to one end of the diode D1 and the diode D2, the other end of the resistor R1 is also connected to the DISC terminal of the main control chip U1, the other ends of the diode D1 and the diode D2 are connected to two ends of the adjustable resistor RP, the adjustment end of the adjustable resistor RP is respectively connected to the TRIG terminal and the THR terminal of the main control chip U1, the adjustment end of the adjustable resistor RP is also connected to one end of the capacitor C2, the other end of the capacitor C2 is respectively connected to one end of the capacitor C1, the other end of the capacitor C1 is connected to the CVOLT terminal of the main control chip U1, the GND terminal of the main control chip U1 and one end of the capacitor C1 are grounded, and the OUT terminal of the main control chip U1 is electrically connected to the switch control terminal of the drive circuit.

[0011] Preferably, the driving circuit includes a transistor Q2 and a MOS transistor Q1, the base of the transistor Q2 is connected to one end of the resistor R2 and the resistor R3 respectively, the other end of the resistor R3 is connected to the emitter of the transistor Q2 and grounded, the other end of the resistor R2 is connected to the OUT end of the main control chip U1, the collector of the transistor Q2 is connected to one end of the resistor R1, the other end of the resistor R1 is connected to the power supply output end of the driving module, the two ends of the resistor R1 are respectively connected in parallel with the source and gate of the MOS tube, and the drain of the MOS tube is electrically connected to the power supply end of the inductor.

[0012] Preferably, the protection circuit includes an overload protection circuit and a short-circuit protection circuit, the overload protection circuit includes a circuit breaker, the short-circuit protection circuit includes a fuse, the power supply end of the power supply module is connected to the power supply input end of the circuit breaker, the power supply output end of the circuit breaker is connected to one end of the fuse, and the other end of the fuse is electrically connected to the power supply end of the reactor.

[0013] Preferably, the feedback sensor includes a current sensor, which detects the magnitude of the current in the line from the reactor to the load.

[0014] Preferably, the feedback sensor includes a voltage sensor, and the voltage sensor detects the voltage of the line from the reactor to the load.

[0015] The beneficial effects of this application are:

[0016] The PWM control circuit adjusts the PWM frequency and duty cycle to control the on and off of the MOS tube Q1 in the drive circuit, thereby controlling the power supply to the reactor, and the voltage and current of the reactor to the load line are detected by the current sensor and voltage sensor in the feedback sensor, so as to control the shutdown of the reactor by the drive circuit by controlling the PWM control circuit, so as to accurately control the reactor, and protect the circuit breaker and fuse in the circuit to avoid damage to the reactor due to overload and short circuit.

[0017] In addition to the above-described purposes, features and advantages, the present application also has other purposes, features and advantages. The present application will be further described in detail below with reference to the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The drawings that constitute part of this application are used to provide a further understanding of this application. The illustrative embodiments of this application and their descriptions are used to explain this application and do not constitute an improper limitation on this application. In the drawings:

[0019] Figure 1 This is a system block diagram of a load box-based reactor precision control circuit of the present utility model;

[0020] Figure 2 This is the PWM control circuit diagram of the utility model;

[0021] Figure 3 This is the driving circuit diagram of the utility model DETAILED DESCRIPTION

[0022] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments in this application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0023] In order to enable those skilled in the art to better understand the present invention, the following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by those skilled in the art without creative work should fall within the scope of protection of the present invention.

[0024] See also Figure 1-3 , the embodiment provided by the utility model:

[0025] A load box-based reactor precision control circuit includes a control circuit for controlling the reactor, the control circuit includes an MCU and a PWM control circuit,

[0026] The control output terminal of the PWM control circuit is electrically connected to the switch control terminal of the drive circuit, such as Figure 2 As shown, specifically, the PWM control circuit includes a main control chip U1, the VCC terminal and the RST terminal of the main control chip U1 are electrically connected to the power supply terminal of the power supply module, and are also connected to one end of the resistor R1, the other end of the resistor R1 is connected to one end of the diode D1 and the diode D2, the other end of the resistor R1 is also connected to the DI SC terminal of the main control chip U1, the other ends of the diode D1 and the diode D2 are connected to two ends of the adjustable resistor RP, the adjustment end of the adjustable resistor RP is respectively connected to the TRIG terminal and the THR terminal of the main control chip U1, the adjustment end of the adjustable resistor RP is also connected to one end of the capacitor C2, the other end of the capacitor C2 is respectively connected to one end of the capacitor C1, the other end of the capacitor C1 is connected to the CVOLT terminal of the main control chip U1, the GND terminal of the main control chip U1 and one end of the capacitor C1 are grounded, and the OUT terminal of the main control chip U1 is electrically connected to the switch control terminal of the drive circuit.

[0027] The main control chip U1 is used to generate a continuous PWM signal. The resistor R1, the adjustable rheostat RP, and the capacitor C2 determine the frequency and duty cycle of the PWM signal. The diodes D1 and D2 are used to control the charging and discharging paths respectively, thereby adjusting the duty cycle of the PWM signal. When the main control chip U1 is at a high level, the capacitor C2 is charged through the resistor R1, the adjustable rheostat RP, and the diode D1. When the voltage of the capacitor C2 reaches 2 / 3VCC, the comparator inside the main control chip U1 is triggered, causing the OUT end of the main control chip U1 to become a low level. By adjusting the adjustable rheostat RP, the charging and discharging time can be changed, thereby adjusting the duty cycle of the PWM signal, and thus providing a PWM signal for the drive circuit.

[0028] The power supply output terminal of the drive circuit is electrically connected to the power supply terminal of the reactor, such as Figure 3 As shown, the driving circuit includes a transistor Q2 and a MOS transistor Q1. The base of the transistor Q2 is connected to one end of the resistor R2 and the resistor R3 respectively. The other end of the resistor R3 is connected to the emitter of the transistor Q2 and grounded. The other end of the resistor R2 is connected to the OUT terminal of the main control chip U1. The collector of the transistor Q2 is connected to one end of the resistor R1. The other end of the resistor R1 is connected to the power supply output terminal of the driving module. The two ends of the resistor R1 are respectively connected in parallel with the source and gate of the MOS transistor. The drain of the MOS transistor is electrically connected to the power supply terminal of the inductor.

[0029] When the PWM signal is at a high level, the base current of the transistor Q2 increases, causing the transistor Q2 to be turned on, reducing the collector voltage, and the gate voltage of the MOS transistor Q1 also decreases. If the gate voltage of the MOS transistor Q1 is lower than the threshold voltage of the MOS transistor, the MOS transistor will enter the shutdown state, and the current between the source and the drain will stop flowing, thereby cutting off the power supply to the reactor, so that the reactor does not work.

[0030] The power supply end of the drive circuit is electrically connected to the power supply module through a protection circuit. The protection circuit includes an overload protection circuit and a short-circuit protection circuit. The overload protection circuit includes a circuit breaker, and the short-circuit protection circuit includes a fuse. The power supply end of the power supply module is connected to the power supply input end of the circuit breaker, and the power supply output end of the circuit breaker is connected to one end of the fuse. The other end of the fuse is electrically connected to the power supply end of the reactor. The circuit breaker and the fuse are used to prevent the reactor from being damaged due to overload and short circuit.

[0031] The inductor is electrically connected to the load through the line, the detection end of the feedback sensor detects the electrical signal between the inductor and the load, the signal output end of the feedback sensor is electrically connected to the signal receiving end of the MCU, the feedback sensor includes a current sensor, the current sensor detects the current size of the inductor to the load line, and the feedback sensor includes a voltage sensor, which detects the voltage size of the inductor to the load line.

[0032] The voltage and current of the line from the reactor to the load are detected by voltage sensors and current sensors, and the detected electrical signals are sent to the MCU for processing through wires. The MCU compares the current and voltage thresholds according to the preset values. When the detected electrical signals are greater than the preset current and voltage thresholds, the PWM control circuit is controlled to control the drive circuit to shut down the reactor, so as to accurately control the reactor.

[0033] The above are merely preferred embodiments of the present application and are not intended to limit the present application. Those skilled in the art will readily appreciate that various modifications and variations are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present application shall be included within the scope of protection of the present application.

Claims

1. A reactor precision control circuit based on a load box, characterized by: It includes a control circuit for controlling the inductor, the control circuit includes an MCU and a PWM control circuit, the control output end of the PWM control circuit is electrically connected to the switch control end of the drive circuit, the power supply end of the drive circuit is electrically connected to the power supply module through the protection circuit, the power supply output end of the drive circuit is electrically connected to the power supply end of the inductor, the inductor is electrically connected to the load through the line, the detection end of the feedback sensor detects the electrical signal between the inductor and the load, and the signal output end of the feedback sensor is electrically connected to the signal receiving end of the MCU.

2. The load box-based reactor precision control circuit according to claim 1, characterized in that: The PWM control circuit includes a main control chip U1. The VCC terminal and RST terminal of the main control chip U1 are electrically connected to the power supply terminal of the power supply module, and are also connected to one end of the resistor R1. The other end of the resistor R1 is connected to one end of the diode D1 and the diode D2. The other end of the resistor R1 is also connected to the DISC terminal of the main control chip U1. The other ends of the diode D1 and the diode D2 are connected to two ends of the adjustable resistor RP. The adjustment end of the adjustable resistor RP is respectively connected to the TRIG terminal and the THR terminal of the main control chip U1. The adjustment end of the adjustable resistor RP is also connected to one end of the capacitor C2. The other end of the capacitor C2 is respectively connected to one end of the capacitor C1. The other end of the capacitor C1 is connected to the CVOLT terminal of the main control chip U1. The GND terminal of the main control chip U1 and one end of the capacitor C1 are grounded. The OUT terminal of the main control chip U1 is electrically connected to the switch control terminal of the drive circuit.

3. The load box-based reactor precision control circuit according to claim 2, characterized in that: The driving circuit includes a transistor Q2 and a MOS transistor Q1. The base of the transistor Q2 is connected to one end of the resistor R2 and the resistor R3 respectively. The other end of the resistor R3 is connected to the emitter of the transistor Q2 and grounded. The other end of the resistor R2 is connected to the OUT end of the main control chip U1. The collector of the transistor Q2 is connected to one end of the resistor R1. The other end of the resistor R1 is connected to the power supply output end of the driving module. The two ends of the resistor R1 are respectively connected in parallel with the source and gate of the MOS transistor. The drain of the MOS transistor is electrically connected to the power supply end of the inductor.

4. The load box-based reactor precision control circuit according to claim 3, characterized in that: The protection circuit includes an overload protection circuit and a short-circuit protection circuit. The overload protection circuit includes a circuit breaker, and the short-circuit protection circuit includes a fuse. The power supply end of the power supply module is connected to the power supply input end of the circuit breaker, the power supply output end of the circuit breaker is connected to one end of the fuse, and the other end of the fuse is electrically connected to the power supply end of the reactor.

5. The reactor precision control circuit based on a load box according to claim 4, characterized in that: The feedback sensor includes a current sensor, which detects the magnitude of the current in the line from the reactor to the load.

6. The reactor precision control circuit based on a load box according to claim 4, characterized in that: The feedback sensor includes a voltage sensor, which detects the voltage magnitude of the line from the reactor to the load.

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