Power device temperature detection system

Abstract

The utility model discloses a power device temperature detection system, which comprises a sampling resistor RS1, a phase voltage detection circuit and an MCU, the phase voltage detection circuit comprises a U-phase detection circuit, a V-phase detection circuit and a W-phase detection circuit, and the U-phase detection circuit, the V-phase detection circuit and the W-phase detection circuit are respectively connected with a power device. The MCU is connected with the sampling resistor RS1, the U-phase detection circuit, the V-phase detection circuit and the W-phase detection circuit, and the U-phase detection circuit, the V-phase detection circuit and the W-phase detection circuit respectively collect UAD, VAD and WAD signals of a power device and transmit the UAD, VAD and WAD signals to the MCU; and the MCU reads the variation of the UAD, VAD and WAD signals and compares the variation with the variation of the sampling signal of the sampling resistor RS1 to detect the temperature change of the corresponding U-phase / V-phase / W-phase lower bridge arm power device.

Description

Technical Field

[0001] The utility model relates to the technical field of power electronics, in particular to a power device temperature detection system. Background Art

[0002] In motor control applications, many power devices require temperature monitoring to prevent damage from overheating. Temperature sensors are typically placed near the power devices in the application circuit to monitor temperature, ensuring they always operate within a safe temperature range. In high-voltage IPM modules, modules with temperature monitoring or over-temperature protection are preferred.

[0003] Existing technologies are primarily divided into two categories. The first involves applications using discrete power devices, primarily employing temperature sensors to detect the temperature near the heat source. The second involves applications using IPM modules, primarily using the real-time voltage output of the IPM module's internal temperature sensor to identify the power device's temperature, or for IPM modules with over-temperature protection to directly shut down upon over-temperature triggering. This first temperature detection method increases the cost of the temperature sensor. IPM modules with temperature detection are relatively expensive on the market, lacking a clear competitive advantage. Utility Model Content

[0004] The purpose of this section is to summarize some aspects of the embodiments of the present invention and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and in the abstract and title of the utility model to avoid obscuring the purpose of this section, the abstract and the title of the utility model, and such simplifications or omissions shall not be used to limit the scope of the present invention.

[0005] Therefore, the purpose of the present invention is to provide a power device temperature detection system, which collects the internal resistance or voltage drop of the power device when it is turned on, compares it with the signal at the sampling resistor end, and calculates the real-time temperature of the power device through software processing.

[0006] In order to solve the above technical problems, according to one aspect of the present invention, the present invention provides the following technical solutions:

[0007] A power device temperature detection system, comprising:

[0008] Sampling resistor RS1;

[0009] A phase voltage detection circuit, comprising a U-phase detection circuit, a V-phase detection circuit, and a W-phase detection circuit, wherein the U-phase detection circuit, the V-phase detection circuit, and the W-phase detection circuit are respectively connected to the power device;

[0010] The MCU is connected to the sampling resistor RS1 and the U-phase detection circuit, the V-phase detection circuit and the W-phase detection circuit, wherein the U-phase detection circuit, the V-phase detection circuit and the W-phase detection circuit respectively collect the U_AD, V_AD and W_AD signals of the power device and transmit them to the MCU. The MCU reads the changes in the U_AD, V_AD and W_AD signals and compares them with the changes in the sampled signals of the sampling resistor RS1 to detect the corresponding temperature changes of the U-phase / V-phase / W-phase lower bridge arm power devices.

[0011] As a preferred solution of the power device temperature detection system described in the present invention, the U-phase detection circuit includes a resistor R13, a resistor R16, a diode D1 and a capacitor C3.

[0012] As a preferred solution of the power device temperature detection system described in the present invention, the V-phase detection circuit is composed of a resistor R14, a resistor R17, a diode D2 and a capacitor C4.

[0013] As a preferred solution of the power device temperature detection system described in the present invention, the W-phase detection circuit is composed of a resistor R15, a resistor R18, a diode D3 and a capacitor C5.

[0014] As a preferred solution of the power device temperature detection system described in the present invention, the power device is a separate power device, a half-bridge IPM module or a full-bridge IPM module.

[0015] As a preferred solution of the power device temperature detection system described in the present invention, the temperature detection of the separated power device is achieved by identifying the temperature of the lower bridge arm power device.

[0016] As a preferred solution of the power device temperature detection system described in the present invention, the half-bridge IPM module is composed of upper and lower bridge arms consisting of two power devices and is encapsulated inside a plastic package. The temperature of the lower bridge arm power device is equivalent to the temperature of the entire half-bridge IPM.

[0017] As a preferred solution of the power device temperature detection system described in the utility model, the full-bridge IPM module integrates three bridge arms and contains six power devices inside a plastic package. The temperature of any lower bridge arm power device is equivalent to the temperature of the three-phase full-bridge IPM.

[0018] Compared with the prior art, the present invention has the following beneficial effects: by collecting the internal resistance or voltage drop of the power device when it is turned on, and then comparing it with the signal at the sampling resistor end, the real-time temperature of the power device is calculated through software processing. The present invention detects the real-time junction temperature of the power device, and the detected temperature change will be more accurate and has nothing to do with the layout and placement of the power device. The NTC detects the ambient temperature and is related to the detected ambient temperature radiation field. The detection error is large, and compared with the half-bridge / full-bridge IPM with temperature detection, the cost is lower. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the present invention will be described in detail below in conjunction with the accompanying drawings and detailed embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without inventive labor. Among them:

[0020] Figure 1 A circuit diagram for performing temperature detection on a single resistor of a separate power device provided in Example 1 of the present utility model;

[0021] Figure 2 A circuit diagram for temperature detection of a half-bridge IPM single resistor module provided in Example 1 of the present utility model;

[0022] Figure 3 A circuit diagram for temperature detection of a three-phase full-bridge single resistor module provided in Example 1 of the present utility model;

[0023] Figure 4 A circuit diagram for temperature detection of dual resistors of a separate power device provided in Example 2 of the present utility model;

[0024] Figure 5 A circuit diagram for temperature detection of a half-bridge IPM dual-resistance module provided in Example 2 of the present utility model;

[0025] Figure 6 A circuit diagram for temperature detection of a three-phase full-bridge dual-resistance module provided in Example 2 of the present utility model;

[0026] Figure 7 A circuit diagram for temperature detection of three resistors of a separate power device provided in Example 3 of the present utility model;

[0027] Figure 8 A circuit diagram for temperature detection of a half-bridge IPM three-resistance module provided in Example 3 of the present utility model;

[0028] Figure 9This is a circuit diagram for temperature detection of a three-phase full-bridge three-resistance module provided in Example 3 of the present utility model. DETAILED DESCRIPTION

[0029] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0030] Next, the present invention is described in detail with reference to schematic diagrams. For ease of illustration, cross-sectional views of device structures may be partially enlarged and not to scale when describing the embodiments of the present invention. Furthermore, the schematic diagrams are merely illustrative and should not limit the scope of protection of the present invention. Furthermore, in actual production, three-dimensional dimensions, including length, width, and depth, should be included.

[0031] In order to make the purpose, technical solutions and advantages of the present invention more clear, the embodiments of the present invention will be described in further detail below with reference to the accompanying drawings.

[0032] The utility model provides a power device temperature detection system, which collects the internal resistance or voltage drop of the power device when it is turned on, compares it with the signal at the sampling resistor end, and calculates the real-time temperature of the power device through software processing.

[0033] The power device temperature detection system includes a sampling resistor RS1, a phase voltage detection circuit and an MCU. The sampling resistor RS1 and the phase voltage detection circuit include a U-phase detection circuit, a V-phase detection circuit and a W-phase detection circuit. The U-phase detection circuit, the V-phase detection circuit and the W-phase detection circuit are respectively connected to the power device. The MCU is connected to the sampling resistor RS1 and the U-phase detection circuit, the V-phase detection circuit and the W-phase detection circuit. The U-phase detection circuit, the V-phase detection circuit and the W-phase detection circuit respectively collect U_AD, V_AD and W_AD signals of the power device and transmit them to the MCU. The MCU reads U_AD, V_AD and W_AD signals. The change in the AD signal is compared with the change in the sampling signal of the sampling resistor RS1 to detect the corresponding temperature change of the U-phase / V-phase / W-phase lower bridge arm power device. The MCU is connected to the sampling resistor RS1 and the U-phase detection circuit, the V-phase detection circuit and the W-phase detection circuit. The U-phase detection circuit, the V-phase detection circuit and the W-phase detection circuit respectively collect the U_AD, V_AD, and W_AD signals of the power device and transmit them to the MCU. The MCU reads the change in the U_AD, V_AD, and W_AD signals and compares the change in the sampling signal of the sampling resistor RS1 to detect the corresponding temperature change of the U-phase / V-phase / W-phase lower bridge arm power device.

[0034] In this embodiment, the U-phase detection circuit includes a resistor R13, a resistor R16, a diode D1 and a capacitor C3, the V-phase detection circuit includes a resistor R14, a resistor R17, a diode D2 and a capacitor C4, and the W-phase detection circuit includes a resistor R15, a resistor R18, a diode D3 and a capacitor C5.

[0035] Among them, the power device is a separate power device, a half-bridge IPM module or a full-bridge IPM module, wherein the separate power device realizes temperature detection by identifying the temperature of the lower bridge arm power device, the half-bridge IPM module is composed of an upper and lower bridge arm consisting of two power devices, which are encapsulated in a plastic package, and the temperature of the lower bridge arm power device is equivalent to the temperature of the entire half-bridge IPM, and the full-bridge IPM module integrates three bridge arms and contains six power devices in a plastic package, and the temperature of any lower bridge arm power device is equivalent to the temperature of the three-phase full-bridge IPM.

[0036] In order to give a detailed introduction to the above-mentioned scheme of a power device temperature detection system of the present invention, the present invention provides the following embodiments 1-3.

[0037] Example 1

[0038] See also Figure 1-Figure 3 , respectively, are the sampling modes of single resistors for discrete devices, half-bridge IPM, and full-bridge IPM. When only any one of the lower bridge arms of U-phase, V-phase, and W-phase is turned on, in this embodiment, the MCU has a processing mode, specifically: the MCU reads the corresponding sampling signals of U_AD, V_AD, and W_AD respectively, and uses the sampling signal of the sampling resistor RS1 as a reference. The ratio of the change in the U_AD, V_AD, and W_AD signals to the change in the sampling signal of the sampling resistor RS1 is used to identify the temperature change of the corresponding U-phase / V-phase / W-phase lower bridge arm power device.

[0039] Example 2

[0040] See also Figure 4-Figure 6, respectively, are discrete devices, half-bridge IPM, and full-bridge IPM dual-resistor sampling methods. The MCU has two processing methods. The first processing method is: when only any one of the lower bridge arms of U phase, V phase, and W phase is turned on, the MCU reads the corresponding sampling signals of U_AD, V_AD, and W_AD respectively. The bus sampling resistor RS1 sampling signal is used as a reference, and the ratio of the change in the U_AD, V_AD, and W_AD signals to the change in the sampling signal of the sampling resistor RS1 is used to identify the temperature change of the corresponding U-phase / V-phase / W-phase lower bridge arm power device. The second processing method is: when only any one of the lower bridge arms of the U-phase, V-phase, and W-phase is turned on, the MCU reads the corresponding sampling signals of U_AD, V_AD, and W_AD respectively. The U_AD signal uses the corresponding phase sampling resistor RS2 signal as a reference, and the ratio of the change in the U_AD signal to the change in the sampling signal of the sampling resistor RS2 is used to identify the temperature rise of the U-phase lower bridge arm power device; the V_AD signal uses the corresponding phase sampling resistor RS3 signal as a reference, and the ratio of the change in the V_AD signal to the change in the sampling signal of the sampling resistor RS3 is used to identify the temperature rise of the V-phase lower bridge arm power device; the W_AD signal uses the bus sampling resistor RS1 signal as a reference, and the ratio of the change in the W_AD signal to the change in the sampling signal of the sampling resistor RS1 is used to identify the temperature rise of the W-phase lower bridge arm power device.

[0041] Example 3

[0042] See also Figure 7-Figure 9 , respectively, for discrete devices, half-bridge IPM, and full-bridge IPM three-resistor sampling. The MCU has two processing methods. The first processing method is: when only any one of the lower bridge arms of phase U, phase V, or phase W is turned on, the MCU reads the corresponding sampling signals of U_AD, V_AD, and W_AD respectively. The sampling signal of bus sampling resistor RS1 is used as a reference. The ratio of the change in the U_AD, V_AD, and W_AD signals to the change in the sampling signal of sampling resistor RS1 is used to identify the temperature change of the corresponding U-phase / V-phase / W-phase lower bridge arm power device. The second processing method is: when only any one of the lower bridge arms of phase U, phase V, or phase W is turned on, the MCU reads the corresponding sampling signals of U_AD, V_AD, and W_AD respectively. The U_AD signal uses the corresponding phase sampling resistor RS2 signal as a reference, and the ratio of the U_AD signal change to the sampling resistor RS2 sampling signal change is used to identify the temperature rise of the U-phase lower arm power device; the V_AD signal uses the corresponding phase sampling resistor RS3 signal as a reference, and the ratio of the V_AD signal change to the sampling resistor RS3 sampling signal change is used to identify the temperature rise of the V-phase lower arm power device; the W_AD signal uses the corresponding phase sampling resistor RS4 signal as a reference, and the ratio of the W_AD signal change to the sampling resistor RS4 sampling signal change is used to identify the temperature rise of the W-phase lower arm power device.

[0043] While the present invention has been described above with reference to specific embodiments, various modifications may be made and equivalent components may be substituted without departing from the scope of the present invention. In particular, as long as no structural conflicts exist, the various features of the embodiments disclosed herein may be combined with one another in any manner, and the omission of an exhaustive description of these combinations in this specification is solely for the sake of space and resource conservation. Therefore, the present invention is not limited to the specific embodiments disclosed herein, but encompasses all technical solutions within the scope of the claims.

Claims

1. A power device temperature detection system, characterized in that: include: Sampling resistor RS1; A phase voltage detection circuit, comprising a U-phase detection circuit, a V-phase detection circuit, and a W-phase detection circuit, wherein the U-phase detection circuit, the V-phase detection circuit, and the W-phase detection circuit are respectively connected to the power device; The MCU is connected to the sampling resistor RS1 and the U-phase detection circuit, the V-phase detection circuit and the W-phase detection circuit, wherein the U-phase detection circuit, the V-phase detection circuit and the W-phase detection circuit respectively collect the U_AD, V_AD and W_AD signals of the power device and transmit them to the MCU. The MCU reads the changes in the U_AD, V_AD and W_AD signals and compares them with the changes in the sampled signals of the sampling resistor RS1 to detect the corresponding temperature changes of the U-phase / V-phase / W-phase lower bridge arm power devices.

2. A power device temperature detection system according to claim 1, characterized in that: The U-phase detection circuit comprises a resistor R13, a resistor R16, a diode D1 and a capacitor C3.

3. A power device temperature detection system according to claim 1, characterized in that: The V-phase detection circuit is composed of a resistor R14, a resistor R17, a diode D2 and a capacitor C4.

4. A power device temperature detection system according to claim 1, characterized in that: The W-phase detection circuit is composed of a resistor R15, a resistor R18, a diode D3 and a capacitor C5.

5. A power device temperature detection system according to claim 1, characterized in that: The power device is a separate power device, a half-bridge IPM module or a full-bridge IPM module.

6. A power device temperature detection system according to claim 5, characterized in that: The separated power devices realize temperature detection by identifying the temperature of the lower arm power device.

7. A power device temperature detection system according to claim 5, characterized in that: The half-bridge IPM module consists of an upper and lower bridge arm consisting of two power devices encapsulated in a plastic package. The temperature of the lower bridge arm power device is equivalent to the temperature of the entire half-bridge IPM.

8. A power device temperature detection system according to claim 5, characterized in that: The full-bridge IPM module integrates three bridge arms and contains six power devices inside a plastic package. The temperature of any lower bridge arm power device is equivalent to the temperature of the three-phase full-bridge IPM.

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