A frequency converter brake unit detection device

Abstract

This invention discloses a testing device for a frequency converter braking unit, relating to the field of frequency converter testing technology. Its purpose is to achieve rapid and accurate testing of the frequency converter braking unit. The device includes an AC power source module, a first DC-DC conversion module, a voltage detection module, a voltage generation module, and a detection indication module. The voltage generation module adjusts the voltage to 750V DC. The voltage detection module detects the output voltage of the voltage generation module. The detection indication module detects and indicates whether there is voltage output at terminals RL1 and RL2 of the braking unit. The positive and negative ports of the AC power source module are connected to the two ends of the input terminal of the voltage generation module. The detection terminal of the voltage detection module is connected to the output terminal of the voltage generation module, and the power supply terminal of the voltage detection module is connected to the output terminal of the first DC-DC conversion module. The input terminal of the first DC-DC conversion module is connected to the AC power source module via a first push-button switch. This invention has the advantages of rapid and accurate testing.

Description

Technical Field

[0001] This invention relates to the field of frequency converter testing technology, and more specifically to the field of a frequency converter braking unit testing device. Background Technology

[0002] Frequency converters are commonly used speed control and drive controllers in ports. When the hoisted load is being lowered, the frequency converter is in generator mode, and the DC bus voltage will rise. When it exceeds 750V, one or more braking units will control the high voltage of the DC bus and transmit it to the braking resistor for consumption. If the braking unit is damaged, the frequency converter will report a fault or even be damaged.

[0003] To ensure the quality of inverter output and its proper functioning during operation, it is necessary to conduct regular inspections of inverters during production and use, with the braking unit being particularly important. Currently, many braking units are tested using an analog multimeter. For example, on the X1 setting of an analog multimeter, the red probe is connected to the positive terminal, and the black probe to the negative terminal. A resistance reading within the infinite range is normal; a low resistance may indicate a damaged braking unit. Similarly, on the X1 setting, the black probe is connected to the positive terminal, and the red probe to the negative terminal. Again, a resistance reading within the infinite range is normal; a low resistance may indicate a damaged braking unit. There are other testing scenarios as well. In general, the condition of the brake is determined based on different connection methods and corresponding measurement results. Therefore, traditional methods are relatively cumbersome, requiring different tests using different ranges and probes to probe the connection points. Furthermore, long-term manual reading of the multimeter can lead to fatigue and inaccurate readings.

[0004] Therefore, achieving a more accurate and rapid braking unit inspection can improve inspection efficiency and accuracy, and further optimize the quality assurance of braking units. Summary of the Invention

[0005] The purpose of this invention is to achieve rapid and accurate detection of the inverter braking unit. To solve the above-mentioned technical problems, this invention provides an inverter braking unit detection device.

[0006] To achieve the above objectives, the present invention specifically adopts the following technical solution:

[0007] A frequency converter braking unit detection device is used to connect to and detect a frequency converter and its braking unit, including an AC source module, a first DC conversion module, a voltage detection module, a voltage generation module and a detection indication module;

[0008] The DC+ and DC- terminals of the braking unit to be tested are connected to the output terminals of the voltage generation module, and the RL1 and RL2 terminals of the braking unit to be tested are connected to the input terminals of the detection indication module. The voltage generation module is used to adjust the voltage to 750V DC, the voltage detection module is used to detect the output voltage of the voltage generation module, and the detection indication module is used to detect and indicate whether there is voltage output at the RL1 and RL2 terminals of the braking unit.

[0009] The positive and negative ports of the AC power source module are connected to the two ends of the input terminal of the voltage generation module.

[0010] The detection terminal of the voltage detection module is connected to the output terminal of the voltage generation module, the power supply terminal of the voltage detection module is connected to the output terminal of the first DC-DC conversion module, and the input terminal of the first DC-DC conversion module is connected to the AC power source module through the first push-button switch. The first push-button switch is located on the line connecting the positive terminal of the AC power source module and the voltage generation module.

[0011] Preferably, the voltage generation module includes a voltage regulation module, a rectification module, a filtering module, a contactor, and a discharge resistor; the contactor includes a relay coil, normally open contacts, and normally closed contacts.

[0012] The relay coil is positioned between the positive and negative terminals of the power supply of the voltage detection module. The positive port of the AC source module is connected to one end of the normally open contact. The negative port of the AC source module and the other end of the normally open contact are connected to the input terminal of the voltage regulator. The positive terminal of the output terminal of the voltage regulator is connected to the input terminal of the rectifier module. The negative terminal of the output terminal of the voltage regulator and the output terminal of the rectifier module are connected to the input terminal of the filter module. The output terminal of the filter module is the output terminal of the voltage generation module. The normally closed contact and the discharge resistor are connected in series between the positive and negative terminals of the output terminal of the filter module.

[0013] Preferably, the rectifier module includes two diodes, and the positive terminal of the output terminal of the voltage regulator is connected to the anode of the first diode and the cathode of the second diode; the cathode of the first diode and the anode of the second diode are the output terminals of the rectifier module.

[0014] Preferably, the filtering module includes two polarized capacitors and two resistors;

[0015] The anode of the first polarized capacitor is connected to the cathode of the first diode and the first terminal of the first resistor, and the second terminal of the first resistor is connected to the first terminal of the second resistor.

[0016] The cathode of the first polarity capacitor is connected to the anode of the second polarity capacitor, and the cathode of the second polarity capacitor is connected to the anode of the second diode and the second terminal of the second resistor.

[0017] The node between the first polarity capacitor and the second polarity capacitor, and the node between the first resistor and the second resistor, are all connected to the negative terminal of the output of the voltage regulator.

[0018] The first end of the first resistor is the positive terminal of the output terminal of the filter module, and the second end of the second resistor is the negative terminal of the output terminal of the filter module.

[0019] Preferably, the detection indicator module includes a light-emitting diode and three resistors;

[0020] The first end of the fourth resistor is connected to the first end of the sixth resistor, the second end of the fourth resistor is connected to the first end of the fifth resistor and the cathode of the light-emitting diode, and the anode of the light-emitting diode is connected to the second end of the sixth resistor.

[0021] The first end of the fourth resistor is the positive terminal of the input terminal of the detection indicator module, and the second end of the fifth resistor is the negative terminal of the input terminal of the detection indicator module.

[0022] Preferably, it further includes a current detection module and a second DC-DC conversion module;

[0023] The detection terminal of the current detection module is connected to the line connecting the positive terminal of the AC power module and the first push-button switch.

[0024] The power supply terminal of the current detection module is connected to the output terminal of the second DC-DC converter module, and the input terminal of the second DC-DC converter module is connected to the AC power source module through the second push-button switch. The second push-button switch is located on the line between the positive terminal of the AC power source module and the detection point of the current detection module.

[0025] Preferably, it also includes two fuses, with the first fuse and the second fuse respectively located at the positive and negative ports of the AC power module.

[0026] The beneficial effects of this invention are as follows:

[0027] This invention features a simple electrical structure, making it easy to integrate into a compact testing instrument, facilitating portability and use by personnel. Furthermore, its simple circuitry results in low cost and high cost-effectiveness. The voltage generation module simulates the DC bus operation of the frequency converter, while the detection and indication module provides voltage feedback, accurately simulating the braking unit's operating environment. The detection results are accurate and intuitive. Moreover, this invention allows for rapid testing simply by plugging in a few ports, resulting in fast and efficient testing. Additionally, the invention includes voltage and current detection modules for easy and intuitive observation of the line's condition. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the inverter braking unit detection device of the present invention;

[0029] Figure 2 This is a schematic diagram of the voltage generation module in Embodiment 2;

[0030] Figure 3 This is a schematic diagram of the detection indication module in Example 3;

[0031] Figure 4 This is a schematic diagram of the inverter braking unit detection device in Example 4;

[0032] Reference numerals: KEY1 - First push-button switch, KEY2 - Second push-button switch, R1 - First resistor, R2 - Second resistor, R3 - Discharge resistor, R4 - Fourth resistor, R5 - Fifth resistor, R6 - Sixth resistor. C1 - First polarity capacitor, C2 - Second polarity capacitor, S1 - Normally open contact, S2 - Normally closed contact, D1 - First diode, D2 - Second diode, D3 - Light-emitting diode, Fuse1 - First fuse, Fuse2 - Second fuse. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0034] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0035] Example 1

[0036] like Figure 1 As shown, a frequency converter braking unit detection device is used to connect to and detect a frequency converter and its braking unit, including an AC source module, a first DC conversion module, a voltage detection module, a voltage generation module and a detection indication module;

[0037] The DC+ and DC- terminals of the braking unit to be tested are connected to the output terminals of the voltage generation module, and the RL1 and RL2 terminals of the braking unit to be tested are connected to the input terminals of the detection indication module. The voltage generation module is used to adjust the voltage to 750V DC, the voltage detection module is used to detect the output voltage of the voltage generation module, and the detection indication module is used to detect and indicate whether there is voltage output at the RL1 and RL2 terminals of the braking unit.

[0038] The positive and negative ports of the AC power source module are connected to the two ends of the input terminal of the voltage generation module.

[0039] The detection terminal of the voltage detection module is connected to the output terminal of the voltage generation module, the power supply terminal of the voltage detection module is connected to the output terminal of the first DC-DC conversion module, and the input terminal of the first DC-DC conversion module is connected to the AC power source module through the first push-button switch KEY1. The first push-button switch is located on the line connecting the positive terminal of the AC power source module and the voltage generation module.

[0040] In this embodiment, the voltage generation module adjusts the voltage to 750V DC, thereby simulating the working state of the DC bus of the frequency converter, and then charging the braking unit. The detection and indication module is used to detect and indicate whether there is voltage output at the RL1 and RL2 terminals of the braking unit, so as to determine whether the braking unit is working normally. After pressing the first button switch KEY1, the positive port of the AC power module is connected to the line connected to the voltage generation module, and the device operates normally. At this time, the voltage detection module can detect the voltage output of the voltage generation module, so as to observe the detection result of the detection and indication module when it is adjusted to 750V. If the detection and indication module detects normal voltage output at the RL1 and RL2 terminals of the braking unit when it is adjusted to 750V, it can be determined that the braking unit is normal.

[0041] Example 2

[0042] This embodiment is based on the technical solution of Embodiment 1, and mainly provides further explanation of the voltage generation module.

[0043] As a preferred embodiment, the voltage generation module includes a voltage regulation module, a rectification module, a filtering module, a contactor, and a discharge resistor R3; the contactor includes a relay coil, normally open contacts, and normally closed contacts.

[0044] The relay coil is positioned between the positive and negative terminals of the power supply of the voltage detection module. The positive port of the AC source module is connected to one end of the normally open contact. The negative port of the AC source module and the other end of the normally open contact are connected to the input terminal of the voltage regulator. The positive terminal of the output terminal of the voltage regulator is connected to the input terminal of the rectifier module. The negative terminal of the output terminal of the voltage regulator and the output terminal of the rectifier module are connected to the input terminal of the filter module. The output terminal of the filter module is the output terminal of the voltage generation module. The normally closed contact and the discharge resistor R3 are connected in series between the positive and negative terminals of the output terminal of the filter module.

[0045] Furthermore, the rectifier module includes two diodes, and the positive terminal of the output terminal of the voltage regulator is connected to the normally closed contact of the first diode, the anode of D1, and the cathode of the second diode, D2; the normally closed contact of the first diode, the cathode of D1, and the anode of the second diode, D2, are the output terminals of the rectifier module.

[0046] On the other hand, the filtering module includes two polarized capacitors and two resistors;

[0047] The anode of the first polarized capacitor is connected to the normally closed contact of the first diode, the cathode of D1 is connected to the first end of the first resistor R1, and the second end of the first resistor R1 is connected to the first end of the second resistor R2.

[0048] The cathode of the first polarity capacitor is connected to the anode of the second polarity capacitor, and the cathode of the second polarity capacitor is connected to the anode of the second diode D2 and the second terminal of the second resistor R2.

[0049] The node between the first polarity capacitor and the second polarity capacitor, and the node between the first resistor R1 and the second resistor R2, are all connected to the negative terminal of the output of the voltage regulator.

[0050] The first end of the first resistor R1 is the positive terminal of the output terminal of the filter module, and the second end of the second resistor R2 is the negative terminal of the output terminal of the filter module.

[0051] After the first button switch KEY1 is pressed, the first DC-DC conversion module starts operating, supplying power to the voltage detection module. At this time, the relay coil is also energized, causing the normally open contact to close. Then, the entire voltage generation module is turned on, which is equivalent to adding a switch layer to the original embodiment 1. The voltage regulator is used to change the voltage magnitude, with the ultimate goal of outputting 750V DC through the voltage regulator. The regulated AC voltage is converted to DC by the rectifier module, then filtered by the filter module, and finally output to the braking unit to be tested. The normally closed contact and discharge resistor R3 are mainly used to detect the discharge after disconnection. During normal detection, the normally closed contact is open. After the detection is disconnected, the relay coil is de-energized, so the normally closed contact closes, and the discharge resistor R3 is added to the circuit to discharge the remaining electricity.

[0052] Example 3

[0053] This embodiment is based on the technical solution of Embodiment 1, and mainly provides further explanation of the detection indication module.

[0054] In this embodiment, refer to Figure 3 The detection indicator module includes a light-emitting diode D3 and three resistors;

[0055] The first end of the fourth resistor R4 is connected to the first end of the sixth resistor. The second end of the fourth resistor R4 is connected to the first end of the fifth resistor R5 and the cathode of the light-emitting diode D3. The anode of the light-emitting diode D3 is connected to the second end of the sixth resistor.

[0056] The first end of the fourth resistor R4 is the positive terminal of the input terminal of the detection indicator module, and the second end of the fifth resistor R5 is the negative terminal of the input terminal of the detection indicator module.

[0057] The voltage detection module observes and adjusts the voltage generation module to output 750V DC to press the braking unit. When there is voltage output at the RL1 and RL2 terminals of the braking unit, the LED D3 will light up, indicating that the braking unit is working normally.

[0058] Example 4

[0059] This embodiment is based on the technical solution of Embodiment 1.

[0060] In this embodiment, a current detection module and a second DC-DC conversion module are also included, and the remaining structure and principle are the same as in Embodiment 1.

[0061] For details, please refer to [link / reference]. Figure 4 The detection terminal of the current detection module is connected to the line connecting the positive terminal of the AC power module and the first push button switch KEY1.

[0062] The power supply terminal of the current detection module is connected to the output terminal of the second DC-DC converter module, and the input terminal of the second DC-DC converter module is connected to the AC power module through the second push-button switch KEY2. The second push-button switch KEY2 is located on the line between the positive terminal of the AC power module and the detection point of the current detection module.

[0063] The current detection module allows for current monitoring to ensure circuit safety. When both the first button switch KEY1 and the second button switch KEY2 are pressed simultaneously, the positive terminal of the AC power source module is connected to the line linking to the voltage generation module, and the entire device operates normally. The current detection module and the voltage detection module then perform their respective monitoring.

[0064] This embodiment also includes two fuses for further circuit safety protection. The first fuse Fuse1 and the second fuse Fuse2 are respectively located at the positive and negative ports of the AC power module.

Claims

1. A device for detecting the braking unit of a frequency converter, used to connect to and detect the braking unit of a frequency converter, characterized in that, The system includes an AC power source module, a first DC-DC converter module, a voltage detection module, a voltage generation module, and a detection indication module. The DC+ and DC- terminals of the braking unit to be tested are connected to the output terminal of the voltage generation module, and the RL1 and RL2 terminals of the braking unit to be tested are connected to the input terminal of the detection indication module. The positive and negative ports of the AC power source module are connected to the two ends of the input terminal of the voltage generation module. The detection terminal of the voltage detection module is connected to the output terminal of the voltage generation module, and the power supply terminal of the voltage detection module is connected to the output terminal of the first DC-DC converter module. The input terminal of the first DC-DC converter module is connected to the AC power source module through a first push-button switch, and the first push-button switch is located on the line connecting the positive port of the AC power source module and the voltage generation module. The voltage generation module includes a voltage regulator, a rectifier module, a filter module, a contactor, and a discharge resistor. The contactor includes a relay coil, a normally open contact, and a normally closed contact. The relay coil is disposed between the positive and negative terminals of the power supply of the voltage detection module. The positive terminal of the AC source module is connected to one end of the normally open contact, and the negative terminal of the AC source module and the other end of the normally open contact are connected to the input terminal of the voltage regulator. The positive terminal of the voltage regulator's output terminal is connected to the input terminal of the rectifier module, and the negative terminal of the voltage regulator's output terminal and the output terminal of the rectifier module are connected to the input terminal of the filter module. The output terminal of the filter module is the output terminal of the voltage generation module. The normally closed contact and the discharge resistor are connected in series between the positive and negative terminals of the output terminal of the filter module. The rectifier module includes two diodes. The positive terminal of the output terminal of the voltage regulator is connected to the anode of the first diode and the cathode of the second diode. The cathode of the first diode and the anode of the second diode are the output terminals of the rectifier module. The filtering module includes two polarized capacitors and two resistors; the anode of the first polarized capacitor is connected to the cathode of the first diode and the first terminal of the first resistor, and the second terminal of the first resistor is connected to the first terminal of the second resistor; the cathode of the first polarized capacitor is connected to the anode of the second polarized capacitor, and the cathode of the second polarized capacitor is connected to the anode of the second diode and the second terminal of the second resistor; the node between the first and second polarized capacitors and the node between the first and second resistors are both connected to the negative terminal of the output of the voltage regulator; the first terminal of the first resistor is the positive terminal of the output of the filtering module, and the second terminal of the second resistor is the negative terminal of the output of the filtering module. The detection indicator module includes a light-emitting diode and three resistors; the first end of the fourth resistor is connected to the first end of the sixth resistor, the second end of the fourth resistor is connected to the first end of the fifth resistor and the cathode of the light-emitting diode, and the anode of the light-emitting diode is connected to the second end of the sixth resistor; the first end of the fourth resistor is the positive terminal of the input terminal of the detection indicator module, and the second end of the fifth resistor is the negative terminal of the input terminal of the detection indicator module.

2. The inverter braking unit detection device according to claim 1, characterized in that, It also includes a current detection module and a second DC-DC conversion module; the detection terminal of the current detection module is connected to the line connecting the positive port of the AC power source module and the first push-button switch; the power supply terminal of the current detection module is connected to the output terminal of the second DC-DC conversion module, the input terminal of the second DC-DC conversion module is connected to the AC power source module through the second push-button switch, and the second push-button switch is located on the line between the positive port of the AC power source module and the detection point of the current detection module.

3. The inverter braking unit detection device according to claim 1, characterized in that, It also includes two fuses, with the first fuse and the second fuse respectively located at the positive and negative ports of the AC power module.

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