Power supply apparatus, electrical system, and temperature measurement method for power supply apparatus

Abstract

A power supply apparatus (100) comprises an inverter (110), voltage and current measuring devices (120a, 120b), a temperature sensor (130), and an operation circuit (140). The inverter (110) comprises change-over switches (SW1-SW6). The voltage and current measuring devices (120a, 120b) are configured to measure the voltage (V1) and the current (I1) on the change-over switches (SW1-SW6). The temperature sensor (130) is configured to measure an initial temperature (T[0]) in an initial state. The operation circuit (140) is coupled to the voltage and current measuring devices (120a, 120b) and the temperature sensor (130). The operation circuit (140) is configured to: execute a power model (142), and calculate a first transient power of the change-over switches (SW1-SW6) on the basis of the initial temperature (T[0]), the voltage (V1), and the current (I1); and execute a thermal model (144), and calculate a first transient ideal temperature of the change-over switches (SW1-SW6) on the basis of the first transient power. The power supply apparatus (100) calculates, in real time, the transient temperature of channel interfaces of the change-over switches (SW1-SW6) by measuring the voltage (V1) and the current (I1) on the change-over switches (SW1-SW6) of the inverter (110). The present invention also relates to a temperature measurement method (500) for a power supply apparatus, and an electrical system (ES1).

Description

Power supply device, electrical system and temperature measurement method thereof Technical Field

[0001] The present invention relates to a power supply device and a temperature measurement method thereof, and more particularly to a cabin monitoring system and method thereof for estimating transient temperature. Background Art

[0002] Thermal management systems in the prior art typically rely on basic thermal models and require manual calibration. This approach can be inefficient and potentially cause malfunctions under varying operating conditions. In the prior art, temperature sensors may also be used to measure the operating temperature of circuit devices. However, existing temperature sensors primarily measure the steady-state temperature of circuit devices, such as the temperature change every 10 seconds during continuous operation of a circuit device. Such steady-state temperature measurements can only represent the overall operating temperature of the circuit device and cannot reflect the transient temperature of a core circuit of the circuit device at a specific moment (e.g., measuring the channel interface temperature of a power switching switch at the moment the switch is switched).

[0003] However, existing temperature sensors are unable to measure or calculate the transient temperature of a specific component within a circuit in real time, which makes temperature monitoring difficult. Summary of the Invention

[0004] This disclosure provides a power supply device. The power supply device includes an inverter, a voltage and current measuring device, a temperature sensor, and a computing circuit. The inverter includes a switch. The voltage and current measuring device is used to measure the voltage and current on the switch. The temperature sensor is used to measure the initial temperature in an initial state. The computing circuit is coupled to the voltage and current measuring device and the temperature sensor. The computing circuit is used to: execute a power model to calculate a first transient power of the switch based on the initial temperature, voltage, and current; and execute a thermal model to calculate a first transient ideal temperature of the switch based on the first transient power.

[0005] This disclosure provides a temperature measurement method for a power supply device, the power supply device comprising an inverter, a voltage and current measuring device, a temperature sensor, and a computing circuit. The inverter includes a switch. The temperature measurement method comprises: measuring voltage and current using the voltage and current measuring device; measuring an initial temperature in an initial state using the temperature sensor; executing a power model using the computing circuit to calculate a first transient power of the switch based on the initial temperature, the voltage and current of the switch; and executing a thermal model using the computing circuit to calculate a first transient ideal temperature of the switch based on the first transient power.

[0006] This disclosure provides an electrical system comprising: a working unit and peripheral locations. The working unit includes a core location configured to generate output energy based on input energy. The peripheral locations correspond to the working unit. The relationship between temperature changes at the core location and the peripheral locations of the electrical system and time corresponds to a thermal impedance function. The electrical system estimates thermal system parameters at the core location of the electrical system using temperature data from the peripheral locations and the thermal impedance function.

[0007] In summary, the power supply device of the present disclosure can measure the voltage and current on the switch of the inverter, and thus calculate the transient temperature of the channel interface of the switch in real time. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] FIG1 is a schematic diagram of an electrical system according to an embodiment of the present disclosure.

[0009] FIG. 2 is a temperature curve diagram of a core position and a peripheral position according to the embodiment of FIG. 1 .

[0010] FIG3 is a schematic diagram of an electrical system according to an embodiment of the present disclosure.

[0011] FIG4 is a schematic diagram of a power supply device according to an embodiment of the present disclosure.

[0012] FIG. 5 is a schematic diagram of a calculation circuit according to the embodiment of FIG. 4 .

[0013] FIG. 6 is a graph showing temperature and power related to the power model according to the embodiment of FIG. 5 .

[0014] FIG. 7 is a graph showing a thermal model according to the embodiment of FIG. 5 .

[0015] FIG8 is a flow chart of a temperature measurement method according to an embodiment of the present disclosure.

[0016] Explanation of reference numerals: ES1, ES2: electrical system WU1, WU2: working units OC1, OC2: peripheral positions CRP1, CRP2: core positions P_in, P_in1, P_in2: input energy P_out, P_out1, P_out2: output energy 100: power supply device 110: inverter SW1, SW2, SW3, SW4, SW5, SW6: switching switch 120a: voltage meter 120b: current meter 130: temperature sensor 140: calculation circuit SC1, SC2: cable GND: ground terminal C1, C2, C3, C4, C5, C6: capacitor CID1 , CID2: coupled inductor MOT1: motor V1: voltage I1: current T[0]: initial temperature T[1]~T[n]: operating environment temperature 142: power model 142a: estimation unit 142b: integration unit 144: thermal model Eon: switch on-state loss power Eoff: switch off-state loss power Erec: reverse recovery loss power Vcond: switch on-state voltage TP[1]~TP[n]: transient power TTI[1]~TTI[n]: transient ideal temperature t1, t2, t3, t4: time point 500: temperature measurement method S510, S520, S530, S540: steps DETAILED DESCRIPTION

[0017] The following will illustrate the embodiments of the present disclosure with reference to the accompanying drawings. In the drawings, the same reference numerals represent the same or similar elements or method flows.

[0018] Embodiment of an electrical system.

[0019] Please refer to FIG. 1 , which is a schematic diagram of an electrical system ES1 according to one embodiment of the present disclosure. In the embodiment of FIG. 1 , the electrical system ES1 includes a working unit WU1 and a peripheral location OC1 (in some embodiments, the peripheral location OC1 refers to peripheral circuitry located near the working unit WU1). The working unit WU1 includes a core location CRP1, and the peripheral location OC1 corresponds to the working unit WU1. The electrical system ES1 receives input energy P_in and generates output energy P_out based on the input energy P_in.

[0020] Example of establishing thermal system parameters.

[0021] Referring to Figure 2, FIG2 shows a temperature curve diagram of the core position CRP1 and the peripheral position OC1 according to the embodiment of FIG1. ​​In this embodiment, the input energy P_in of the electrical system ES1 includes thermal energy input, which heats the core position CRP1 of the working unit WU1, raising its temperature until the thermal energy input generated by the input energy P_in and the thermal energy output generated by the output energy P_out of the core position CRP1 reach equilibrium, causing the core position CRP1 and the peripheral position OC1 to reach a steady-state temperature. The input energy P_in is then reduced or stopped, causing the core position CRP1 and the peripheral position OC1 to begin cooling. This results in the temperature change versus time relationship of the core position CRP1 and the peripheral position OC1 shown in FIG2. By converting the temperature change versus time relationship of the core position CRP1 and the peripheral position OC1 through a thermal impedance curve, a thermal impedance function can be further obtained to establish thermal system parameters.

[0022] In the aforementioned embodiments, the JEDEC 51-14 test method can be used, or in conjunction with thermocouple wire, to capture transient voltage changes at the measurement point of the object under test. This technology converts voltage data into temperature rise data, thereby obtaining the time-thermal resistance and thermal resistance-heat capacity relationships of the object under test. These relationships can be used for dynamic monitoring to obtain the electrical system ES1 thermal impedance function or establish thermal system parameters.

[0023] An embodiment of establishing electrical system parameters.

[0024] In one embodiment, the input energy P_in of the electrical system ES1 includes electrical energy input, and the operating conditions of the working unit WU1 are controlled based on the key electrical characteristics of the working unit WU1. Under the control of the operating conditions of the working unit WU1, the working unit WU1 can output output energy P_out. By establishing a relationship between the key electrical characteristics of the working unit WU1 and the operating conditions, electrical system parameters can be established.

[0025] In this embodiment, the electrical system ES1 may be any device for transferring or converting mechanical and electrical energy. The electrical system ES1 may have thermal characteristics during the energy transfer or conversion process. Therefore, thermal system parameters can be established by converting the temperature change and time relationship between the core position CRP1 and the peripheral position OC1 into a thermal impedance function through thermal impedance curve conversion. When the electrical system ES1 is operated, the transient thermal resistance and temperature of the core position CRP1 of the electrical system ES1 can be estimated by temperature sensing of the peripheral position OC1 and the thermal impedance function of the electrical system ES1. Therefore, this embodiment can provide multiple reference values, and these reference values ​​can be transient thermal resistance detection of the core position CRP1, temperature detection of the core position CRP1, component overheat protection, and / or control parameters of the working unit WU1 when the electrical system ES1 is in operation.

[0026] In other words, the electrical system ES1 may perform overheat protection on the working unit WU1 according to the thermal system parameters of the core position CRP1 and / or use the thermal system parameters as control parameters.

[0027] In this embodiment, the dynamic temperature of the core position CRP1 of the working unit WU1 can be measured, for example, by monitoring the change in junction voltage of a semiconductor device under forward bias operation. Therefore, the electrical system ES1 can estimate the transient thermal resistance of the core position CRP1 by using the temperature sensing of the peripheral position OC1 and the thermal impedance function of the electrical system ES1. The transient thermal resistance displacement can be compared with the dynamic temperature measurement of the core position CRP1 to further assess the degree of aging of a physical state of the core position CRP1 of the working unit WU1.

[0028] In the aforementioned embodiment, the aging degree of the physical state of the core position CRP1 of the working unit WU1 can be evaluated by comparing the thermal system parameters with the temperature data of the peripheral position OC1 through the thermal impedance function and referring to the electrical system parameters.

[0029] Example of transient thermal resistance displacement.

[0030] In the aforementioned embodiment, when the system configuration of the electrical system ES1 whose thermal system parameters and electrical system parameters have been obtained is changed, a Computer Aided Engineering (CAE) simulation can be performed based on the difference in the system configuration change of the electrical system ES1 to obtain the thermal system parameters and electrical system parameters of the electrical system ES1 after the configuration change.

[0031] In the aforementioned embodiment, the thermal system parameters can be estimated by comparing the thermal impedance function with the temperature data of the peripheral position OC1, referring to the working conditions of the working unit WU1, and comparing the thermal system parameters obtained by computer-aided engineering with the electrical system parameters to evaluate the transient thermal resistance displacement, thereby estimating the aging degree of the working unit WU1.

[0032] Please refer to FIG3 , which is a schematic diagram of an electrical system ES2 according to an embodiment of the present disclosure. The electrical system ES2 includes a work unit WU1 , and the work unit WU1 of the electrical system ES2 has the same thermal and electrical system parameters as the electrical system ES1 of FIG1 . When the work unit WU1 of the electrical system ES2 is replaced with the work unit WU2 , a computer-aided engineering (CAE) simulation can be performed based on the differences between the work unit WU1 and the work unit WU2 to obtain the thermal and electrical system parameters of the electrical system ES2 replaced with the work unit WU2 .

[0033] In this embodiment, the input energies P_in1 and P_in2 of the electrical system ES2 both include electrical energy input, and control the working conditions of the key electrical characteristics of the working units WU1 and WU2 respectively.

[0034] Under the control of the working condition of working unit WU1, working unit WU1 can output output energy P_out1, and working unit WU2 can output output energy P_out2. By establishing the relationship between the key electrical characteristics of working units WU1 and WU2 and the working conditions, electrical system ES2 can establish electrical system parameters.

[0035] In this embodiment, the electrical system ES2 may be any device for transmitting or converting mechanical and electrical energy. The electrical system ES2 may exhibit thermal characteristics during the energy transmission or conversion process. Therefore, thermal system parameters can be established by analyzing the relationship between the temperature changes and time at the core locations CRP1 and CRP2 and the peripheral locations OC1 and OC2 (in some embodiments, the peripheral location OC2 refers to a peripheral circuit located near the work unit WU2, and the circuit at the peripheral location OC2 is different from the circuit at the peripheral location OC1) and converting the temperature curve to obtain a thermal impedance function. When the electrical system ES2 is in operation, the transient thermal resistance and temperature of the core locations CRP1 and CRP2 of the electrical system ES2 can be estimated by temperature sensing at the peripheral locations OC1 and OC2 and the thermal impedance function of the electrical system ES2. Therefore, this embodiment can provide multiple reference values, and these reference values ​​can be the transient thermal resistance detection of the core position CRP1 when the electrical system ES2 is operating, the transient thermal resistance detection of the core position CRP2, the core position CRP1 temperature detection, the core position CRP2 temperature detection, the component overheating protection, the control parameters of the working unit WU1, and the control parameters of the working unit WU2.

[0036] In this embodiment, the dynamic temperature of the core position CRP1 of the working unit WU1 can be measured. Therefore, the electrical system ES2 can estimate the transient thermal resistance of the core position CRP1 by using the temperature sensing of the peripheral position OC1 and the thermal impedance function of the electrical system ES2. The temperature is compared with the dynamic temperature measurement of the core position CRP1, and the transient thermal resistance displacement is evaluated to further assess the degree of aging of a physical state of the core position CRP1 of the working unit WU1.

[0037] Furthermore, the dynamic temperature of the core position CRP2 of the work unit WU2 can be measured. Therefore, the electrical system ES2 can estimate the transient thermal resistance of the core position CRP2 by using the temperature sensing of the peripheral position OC2 and the thermal impedance function of the electrical system ES2. The temperature can be compared with the dynamic temperature measurement of the core position CRP2, and the transient thermal resistance displacement can be evaluated to further assess the degree of aging of a physical state of the core position CRP2 of the work unit WU2.

[0038] In one embodiment, the electrical system ES2 may further include a plurality of working units. According to this embodiment, the electrical system ES2 may include thermal system parameters and electrical system parameters of the plurality of working units.

[0039] In this embodiment, the plurality of working units of the electrical system ES2 may include working units WU1 and WU2. Thermal system parameters and electrical system parameters may be obtained for working units WU1 and WU2, respectively, according to the above-described embodiments. Computer-aided engineering simulations may be performed on the electrical system ES2 including working units WU1 and WU2 based on the differences between the working units to obtain thermal system parameters and electrical system parameters for the electrical system ES2 including both working units WU1 and WU2.

[0040] Inverter-related embodiments.

[0041] Please refer to Figure 4, which is a schematic diagram of a power supply device 100 according to an embodiment of the present disclosure. The working unit WU1 in Figure 1 may correspond to the remaining circuits of the power supply device 100 in Figure 3 , excluding the motor MOT1. In Figure 3, the power supply device 100 includes at least an inverter 110, a voltage meter 120a, a current meter 120b, a temperature sensor 130, and a computing circuit 140. Furthermore, the power supply device 100 may include cables SC1 and SC2, coupled inductors CID1 and CID2, capacitors C1-C6, and the motor MOT1.

[0042] In one embodiment, the inverter 110 of the power supply device 100 includes switches SW1 - SW6 . The main function of the inverter 110 is to convert DC input into AC output of a specific specification.

[0043] In one embodiment, the power supply device 100 can be used in the power supply system of an electric vehicle (as shown in the embodiment of FIG. 4 , to power the drive motor MOT1). However, the present disclosure is not limited thereto. The power supply device 100 can also be used in a renewable energy system (such as solar or wind energy) or a power supply device based on direct current (such as a battery) feeding power to an alternating current (AC) grid. In these examples, the load will be replaced by an AC grid (not shown) or other similar AC power load instead of the motor MOT1 shown in FIG. 4 . The inverter 110 is used to convert a DC power input (such as a battery, solar panel, or wind turbine) into a specific AC power output.

[0044] In one embodiment, the switching switches SW1 to SW6 can be insulated gate bipolar transistors (IGBTs) or metal oxide semiconductor field effect transistors (MOSFETs), respectively. The operation circuit 140 is used to generate gate signals to drive the switching switches SW1 to SW6, thereby controlling the operation of the switching switches SW1 to SW6. The switching switches SW1 to SW6 respectively switch their switching states according to the gate signals to generate three-phase alternating current. The switching switches SW1 to SW6 are controlled by precise switching actions to generate waveforms of the required frequency and voltage. Three groups of switching switches SW1 to SW6 form a three-phase system, and each group controls the voltage of one phase, thereby forming a balanced three-phase alternating current. By adjusting the switching speed of the switching switches SW1 to SW6, the output frequency can be adjusted, thereby controlling the motor speed (for example, the speed of motor MOT1). Precise switching control can minimize energy loss and improve system efficiency. Furthermore, when the computing circuit 140 determines that switches SW1-SW6 have an abnormality (e.g., transient overtemperature or insufficient service life), the computing circuit 140 can shut down switches SW1-SW6 to quickly cut off the current, protecting the system from damage caused by overload or faults. The coordinated operation of switches SW1-SW6 ensures stable and efficient operation of the inverter 110.

[0045] In one embodiment, the computing circuit 140 of the present disclosure monitors / estimates the transient temperature at the channel interfaces of each of the switches SW1-SW6 of the inverter 110 to control and provide overtemperature protection for the switches SW1-SW6. In this embodiment, the switches SW1-SW6 in FIG4 correspond to the core position CRP1 in FIG1 . As described above, the temperature curve of the core position CRP1 in FIG2 can be used to determine the temperature changes of the switches SW1-SW6. Furthermore, the following embodiments will further explain in detail how the computing circuit 140 of the present disclosure monitors / estimates the transient temperature and performs the subsequent overtemperature protection.

[0046] In one embodiment, cables SC1 and SC2 can receive an input voltage and be coupled to ground GND. Cable SC1 can also be coupled to a first terminal of capacitor C1. The first terminal of capacitor C1 is coupled to ground GND and a first terminal of capacitor C2. Cable SC2 can also be coupled to a second terminal of capacitor C2. In one embodiment, cables SC1 and SC2 can each be a shielded cable coated with an insulating material.

[0047] A first input terminal of coupled inductor CID1 is coupled to the first terminal of capacitor C1. A first output terminal of coupled inductor CID1 is coupled to the first terminal of capacitor C3 and the first terminal of capacitor C4. A second input terminal of coupled inductor CID1 is coupled to the second terminal of capacitor C2. A second output terminal of coupled inductor CID1 is coupled to the second terminal of capacitor C3 and ground GND. A second terminal of capacitor C4 is coupled to ground GND.

[0048] As shown in FIG4 , capacitors C5 and C6 may also be provided within inverter 110. A first end of switch SW1 is coupled to capacitor C4, capacitor C5, a first end of switch SW2, capacitor C6, and a first end of switch SW3. A second end of switch SW1 is coupled to a first end of switch SW4. A second end of switch SW2 is coupled to a first end of switch SW5. A second end of switch SW3 is coupled to a first end of switch SW6. The second ends of switches SW4, SW5, and SW6 are all coupled to ground GND.

[0049] The measuring end of the voltage measuring device 120a can be set in the inverter 110, for example, at the first end of the switching switch SW1, to measure the voltage V1 on the switching switch SW1. The measuring end of the current measuring device 120b can be set in the inverter 110, for example, at the second end of the switching switch SW1, to measure the current I1 flowing through the switching switch SW1. The measuring end of the temperature sensor 130 can be set in the inverter 110 to measure the initial temperature T[0] of the inverter 110 at the moment of starting operation (also called the "initial state") and the operating environment temperature T[1]~T[n] after the inverter 110 has been running for a period of time. Here, "n" can be any positive integer greater than 1, representing the number of times the temperature sensor 130 measures the inverter 110 during the operation of the inverter 110, and also represents the number of operating environment temperatures measured by the temperature sensor 130 from the inverter 110. In some embodiments, the measuring end of the temperature sensor 130 may also be disposed outside the inverter 110 , and the present invention is not limited thereto.

[0050] The inverter 110 is coupled to the input terminal of the coupled inductor CID2 . The three-phase input terminals of the motor MOT1 are coupled to the output terminal of the coupled inductor CID2 .

[0051] The computing circuit 140 is coupled to the voltage measurer 120a, the current measurer 120b, and the temperature sensor 130. The computing circuit 140 receives the voltage V1 through the voltage measurer 120a, the current I1 through the current measurer 120b, and the initial temperature T[0] and the operating environment temperatures T[1]-T[n] through the temperature sensor 130.

[0052] Wafer temperature estimation - an embodiment of timely protection.

[0053] In one embodiment, the computing circuit 140 of FIG. 4 may execute the power model 142 and the thermal model 144 to calculate the transient ideal temperatures TTI[1]-TTI[n].

[0054] In the initial state, the computing circuit 140 may receive the initial temperature T[0] via the temperature sensor 130. The computing circuit 140 may execute the power model 142 and calculate the transient power TP[1] based on the initial temperature T[0], the voltage V1 measured by the voltage meter 120a in the initial state, and the current I1 measured by the current meter 120b in the initial state. After calculating the transient power TP[1], the computing circuit 140 may then execute the thermal model 144 and calculate the transient ideal temperature TTI[1] of the switch SW1 based on the transient power TP[1].

[0055] After the initial state, the power supply device 100 can continue to operate. The temperature inside the inverter 110 will increase over time, and the thermal resistance of the switching switch SW1 will change as the temperature increases, thereby changing the voltage V1 and current I1 on the switching switch SW1. When the power supply device 100 is operating, the operation circuit 140 can first receive the initial temperature T[0] through the temperature sensor 130 and execute the power model 142 to calculate the transient power TP[2] of the switching switch SW1 based on the transient ideal temperature TTI[1], the voltage V1 measured in real time by the voltage meter 120a, and the current I1 measured in real time by the current meter 120b. After calculating the transient power TP[2], the operation circuit 140 can then execute the thermal model 144 and calculate the transient ideal temperature TTI[2] of the switching switch SW1 based on the transient power TP[2].

[0056] Next, the computing circuit 140 may continuously execute the power model 142 and the thermal model 144 and calculate the transient ideal temperature TTI[3] based on the voltage V1, the current I1, and the transient ideal temperature TTI[2]. The computing circuit 140 may iterate the above operation continuously to infer the temperature value of the switching switch SW1 at a certain point in time based on the voltage V1 and the current I1 of the switching switch SW1 at that point in time.

[0057] In summary, based on the power model 142 and the thermal model 144 , the power supply device 100 can calculate the transient temperature of the switch SW1 in real time by only measuring the voltage V1 and the current I1 on the switch SW1 of the inverter.

[0058] In addition to the above functions, in the embodiment of FIG. 4 , the computing circuit 140 of the power supply device 100 can further compare the transient ideal temperature of the switch SW1 at a certain time point after the power supply device 100 operates from the initial state to the operating environment temperature measured by the temperature sensor at that time point, thereby determining whether an abnormality has occurred in the switch SW1.

[0059] The computational circuit 140 can use the power model 142 and the thermal model 144 to estimate the transient ideal temperature of the switch SW1 at the aforementioned point in time. The computational circuit 140 can receive the operating ambient temperature measured by the temperature sensor 130 at that point in time. Furthermore, the computational circuit 140 can set a conduction function, which is determined based on the distance between the switch SW1 and the measuring end of the temperature sensor 130 and the thermal conductivity of the conductive medium between them (e.g., air, a heat pipe, or a heat-conducting metal sheet). The computational circuit 140 can convert the operating ambient temperature into the switch operating temperature of the switch SW1 based on the conduction function. In other words, the computational circuit 140 can estimate the switch operating temperature of the switch SW1 based on the conduction function and the operating ambient temperature. The computational circuit 140 can compare the switch operating temperature of the switch SW1 with the transient ideal temperature to determine whether the switch SW1 has experienced an abnormality at that point in time.

[0060] When the difference between the switch operating temperature and the transient ideal temperature exceeds a first threshold, it indicates that switch SW1 has aged, resulting in an increase in its thermal resistance. In this case, computing circuit 140 can send a control signal to reduce current I1 flowing through switch SW1, placing switch SW1 in load reduction mode to extend the service life of switch SW1.

[0061] When the difference between the switch operating temperature and the transient ideal temperature exceeds a second threshold, it indicates that switch SW1 has aged excessively. Continued use of switch SW1 could cause the entire power supply device 100 to malfunction. In this embodiment, the second threshold is higher than the first threshold. In this case, the computing circuit 140 can send a control signal to stop switch SW1 (or the entire inverter 110) or cause switch SW1 to supply zero-sequence current to motor MOT1. In some embodiments, when the computing circuit 140 detects this phenomenon, it can generate and transmit a warning message (e.g., explanatory text, graphics, or an audible alarm) to a display, speaker, or other output interface. This notifies the user or maintenance personnel of the current aging of switch SW1, allowing them to perform targeted repairs or maintenance.

[0062] In the above embodiment, a widening gap between the switch operating temperature and the transient ideal temperature may indicate that switches SW1-SW6 have worn out or have a limited service life. For example, a Rainflow algorithm can be executed to estimate the service life of switches SW1-SW6 based on the deviation in their operating temperatures. If it is determined that switches SW1-SW6 have reached a limited service life, maintenance personnel can be prompted to replace them. In some embodiments, the service life of a specific switch among the six switches can be identified and a targeted replacement reminder can be issued.

[0063] In the above embodiment, for simplicity, the inverter switch SW1 is used as an example. In one embodiment, the computing circuit 140 can receive the voltage across and current through each of the other switches SW2-SW6, and then perform transient temperature estimation and overtemperature monitoring for the other switches SW2-SW6. In another embodiment, the computing circuit 140 can simultaneously monitor each of the switches SW1-SW6 and select the highest transient temperature calculated by the computing circuit 140 for these switches to determine whether the inverter 110 is overheated.

[0064] Furthermore, in one embodiment, the computing circuit 140 can simultaneously perform transient temperature estimation and over-temperature monitoring on one or more of the switches SW1 - SW6 .

[0065] Please refer to FIG5 , which is a schematic diagram of the computing circuit 140 according to the embodiment of FIG4 . Specifically, FIG5 illustrates a power model 142 and a thermal model 144 of the computing circuit 140 .

[0066] In the embodiment of FIG. 5 , the power model 142 includes an estimation unit 142 a and an integration unit 142 b .

[0067] In the initial state, the estimation unit 142a can estimate the switch on-state power Eon, switch off-state power Eoff, reverse recovery power Erec and switch on-state voltage Vcond of the switch SW1 according to the initial temperature T[0], the voltage V1 and the current I1 of the switch SW1.

[0068] Switch conduction loss Eon is the power lost when switch SW1 switches from the off state to the on state. By measuring the changes in voltage V1 and current I1 when switch SW1 switches to the on state, switch conduction loss Eon can be calculated.

[0069] The switch-off power loss Eoff is the power lost when the switch SW1 switches from the on state to the off state. By detecting the changes in voltage V1 and current I1 when the switch SW1 switches to the off state, the switch-off power loss Eoff can be calculated.

[0070] Regarding reverse recovery power loss Erec, when the voltage V1 applied to switch SW1 changes from the forward direction to the reverse direction, switch SW1 does not immediately turn off. Switch SW1 takes a while to transition from the on state to the off state, a period known as the reverse recovery time. During this time, current I1 flows in the reverse direction, generating a reverse recovery current. By measuring the voltage V1 and current I1 during this time, the reverse recovery power loss Erec of switch SW1 can be calculated.

[0071] The switch-on voltage Vcond refers to a voltage that causes the switching switch SW1 to enter the on state.

[0072] In this embodiment, the integration unit 142b may receive the switch on-state power loss Eon, the switch off-state power loss Eoff, the reverse recovery power loss Erec, and the switch on-state voltage Vcond from the estimation unit 142a, and calculate the transient power TP[1] based on these received values.

[0073] The thermal model 144 may receive the transient power TP[1] from the integration unit 142 b and calculate the transient ideal temperature TTI[1] based on the transient power TP[1].

[0074] After the initial state, the thermal model 144 can transmit the transient ideal temperature TTI[1] to the power model 142. The power model 142 can correspondingly output the transient power TP[2] to the thermal model 144, so that the thermal model 144 can calculate the transient ideal temperature TTI[2]. Similarly, the calculation circuit 140 can continue to calculate the transient ideal temperatures TTI[3] to TTI[n].

[0075] Please refer to FIG. 6 , which is a graph showing temperature and power associated with the power model 142 according to the embodiment of FIG. 5 .

[0076] As can be seen from FIG. 6 , the temperature of the power supply device 100 during operation increases over time, and the values ​​of the operating environment temperatures T[1] to T[n] also gradually increase accordingly.

[0077] Before time t1, the power conducted by switch SW1 increases with the temperature of power supply device 100. Between time t1 and time t2, since switch SW1 is in the off state, the power conducted by switch SW1 returns to zero. Between time t2 and time t3, switch SW1 returns to the on state, and the power conducted by switch SW1 increases with the temperature of power supply device 100. Between time t3 and time t4, switch SW1 turns off again, and the power conducted by switch SW1 returns to zero. After time t4, switch SW1 returns to the on state, and the power conducted by switch SW1 increases with the temperature of power supply device 100.

[0078] At time points t1 and t3, the switch SW1 switches from the on state to the off state, generating switch off power loss Eoff. At time points t2 and t4, the switch SW1 switches from the off state back to the on state, generating switch on power loss Eon.

[0079] It should be noted that, in one embodiment, the power model 142 is established based on the measurement results in the laboratory. That is, an operating environment equivalent to that of the power supply device 100 is constructed in the laboratory environment, and the ambient temperature is controlled. The switch on-state loss power Eon, switch off-state loss power Eoff, reverse recovery loss power Erec, and switch on-state voltage Vcond corresponding to the switching switch SW1 under different on-state voltages and on-state currents are measured one by one, thereby obtaining various power characteristics of the switching switch SW1 under different on-state voltages and on-state currents at a specific ambient temperature. In some embodiments, these power characteristics are recorded as a comparison table or as a database model to obtain the power model 142.

[0080] Please refer to Figure 7, which is a graph related to the thermal model 144 according to the embodiment of Figure 5. The graph of Figure 7 includes a measured curve and an estimated curve, each of which represents the corresponding relationship between the thermal resistance value of the switch SW1 and the thermal capacitance value of the switch SW1.

[0081] In FIG. 7 , the measured curve is a preset curve obtained by measuring the thermal resistance and thermal capacitance of the chip, substrate, solder joints, fin headers, and circuit operating environment used by the power supply device 100 .

[0082] Referring to the measurement curve of FIG. 7 , the thermal model 144 can convert the transient powers TP[1]-TP[n] into transient ideal temperatures TTI[1]-TTI[n] one by one and plot the measurement curve of FIG. 7 .

[0083] By comparing the positional relationship between the measurement curve and the measurement curve in FIG. 7 , it is possible to more intuitively understand whether the switch SW1 of the power supply device 100 has an abnormality.

[0084] It should be noted that, in one embodiment, the thermal model 144 is established based on the measurement results in the laboratory. That is, an environment equivalent to the operating environment of the power supply device 100 is constructed in the laboratory environment, and the ambient temperature and the on-current are controlled. The voltage across the switching switch SW1 is measured one by one, and the power loss of the switching switch SW1 is inferred from the on-current and the voltage across the switching switch SW1. In some embodiments, the relationship between the power loss and the ambient temperature is recorded as a comparison table or a database model to obtain the thermal model 144.

[0085] Example of predicting maintenance time.

[0086] Please refer to FIG8 . FIG8 is a flow chart of a temperature measurement method 500 according to an embodiment of the present disclosure. The temperature measurement method 500 is used to illustrate the operation method of the power supply device 100 .

[0087] In step S510 , the power supply device 100 may measure the voltage V1 and the current I1 on the switch SW1 through the voltage and current measuring devices (ie, the voltage measuring device 120 a and the current measuring device 120 b ).

[0088] In step S520 , the power supply device 100 may measure the initial temperature T[0] in the initial state through the temperature sensor 130 .

[0089] In step S530 , the power supply device 100 may execute the power model 142 to calculate the transient power TP[ 1 ] based on the initial temperature T[ 0 ], the voltage V1 of the switch SW1 , and the current I1 .

[0090] In step S540 , the power supply device 100 may execute the thermal model 144 to calculate the transient ideal temperature TTI[1] of the switch SW1 based on the transient power TP[1]. In this step, the power supply device 100 may also record the thermal system parameters and electrical system parameters generated by the thermal model 144 .

[0091] After step S540, the power supply device 100 may receive the transient ideal temperature TTI[1] and continuously calculate the transient ideal temperatures TTI[2]-TTI[n] according to the temperature measurement method 500. In this step, the power supply device 100 may also record the numerical changes of the thermal system parameters and the electrical system parameters by recording multiple sets of thermal system parameters and electrical system parameters.

[0092] In this embodiment, the power supply device 100 can analyze the numerical changes in thermal and electrical system parameters through numerical fitting, statistical methods, artificial intelligence deep learning, and other methods, and predict the time point at which the inverter 110 will reach degradation based on these records. The time point can be replaced by various representations such as "electric vehicle mileage" or "number of trips," or simply a date and time, and the present invention is not limited to this.

[0093] In summary, based on power model 142 and thermal model 144, the power supply device 100 of the present invention can calculate the transient temperature of the inverter switch in real time by simply measuring the voltage and current on the inverter switch. Furthermore, in some cases, the power supply device 100 of the present invention can also determine whether the inverter has aged by comparing the transient ideal temperature with the ambient temperature during system operation.

[0094] The above are only preferred embodiments of the present disclosure. Various modifications and equivalents may be made to the present disclosure without departing from the scope or concept of the present disclosure. In summary, all modifications and equivalents made to the present disclosure within the scope of the claims are within the scope of the present disclosure.

Claims

1. A power supply device, comprising: An inverter including a switch; a voltage and current measuring device for measuring a voltage and a current on the switch; a temperature sensor for measuring an initial temperature in an initial state; as well as An operating circuit is coupled to the voltage and current measuring device and the temperature sensor, and is used to: executing a power model to calculate a first transient power of the switch based on the initial temperature, the voltage of the switch, and the current; as well as A thermal model is executed to calculate a first transient ideal temperature of the switch based on the first transient power.

2. The power supply device as claimed in claim 1 , wherein the computing circuit is further configured to: When the power supply device is running, executing the power model to calculate a second transient power of the switch according to the first transient ideal temperature, the voltage, and the current; and The thermal model is executed to calculate a second transient ideal temperature of the switch according to the second transient power.

3. The power supply device as claimed in claim 1 , wherein the computing circuit is further configured to: When the power supply device is running, measuring an operating environment temperature through the temperature sensor; estimating a switch operating temperature of the switch according to the operating environment temperature and a conduction function between the switch and the temperature sensor; The operating temperature of the switch is compared with the first transient ideal temperature to determine whether the switch relationship is abnormal.

4. The power supply device according to claim 3, wherein: When the difference between the operating temperature of the switch and the first transient ideal temperature is greater than a first threshold value, the operation circuit sends a control signal to reduce the current flowing through the switch. When the difference between the operating temperature of the switch and the first transient ideal temperature is greater than a second threshold value, the operation circuit sends the control signal to stop the switch from operating, and the second threshold value is higher than the first threshold value.

5. The power supply device as claimed in claim 1 , wherein the power model estimates a switch-on loss power, a switch-off loss power, a reverse recovery loss power, and a switch-on voltage of the switch according to the initial temperature, the voltage of the switch, and the current of the switch, and calculates the first transient power according to the switch-on loss power, the switch-off loss power, the reverse recovery loss power, and the switch-on voltage.

6. A method for measuring the temperature of a power supply device, the power supply device comprising an inverter, a voltage and current measuring device, a temperature sensor, and an operating circuit, the inverter comprising a switch, the temperature measuring method comprising: Measuring a voltage and a current on the switch by the voltage and current measuring device; Measuring an initial temperature in an initial state by the temperature sensor; Executing a power model by the calculation circuit to calculate a first transient power of the switch based on the initial temperature, the voltage of the switch, and the current of the switch; and A thermal model is executed by the calculation circuit to calculate a first transient ideal temperature of the switch based on the first transient power.

7. The temperature measurement method according to claim 6, further comprising: When the power supply device is running, executing the power model to calculate a second transient power of the switch according to the first transient ideal temperature, the voltage, and the current; and The thermal model is executed to calculate a second transient ideal temperature of the switch according to the second transient power.

8. The temperature measurement method according to claim 6, further comprising: When the power supply device is running, measuring an operating environment temperature through the temperature sensor; estimating a switch operating temperature of the switch according to the operating environment temperature and a conduction function between the switch and the temperature sensor; The operating temperature of the switch is compared with the first transient ideal temperature to determine whether the switch relationship is abnormal.

9. The temperature measurement method according to claim 8, further comprising: When the difference between the operating temperature of the switch and the first transient ideal temperature is greater than a first threshold value, a control signal is sent to reduce the current flowing through the switch. When the difference between the operating temperature of the switch and the first transient ideal temperature is greater than a second threshold value, the control signal is sent to stop the switch from operating, and the second threshold value is higher than the first threshold value.

10. The temperature measurement method of claim 6 , wherein the power model estimates a switch-on loss power, a switch-off loss power, a reverse recovery loss power, and a switch-on voltage of the switch according to the initial temperature, the voltage of the switch, and the current of the switch, and calculates the first transient power according to the switch-on loss power, the switch-off loss power, the reverse recovery loss power, and the switch-on voltage.

11. An electrical system comprising: a working unit comprising a core position for generating an output energy according to an input energy; and A peripheral position corresponding to the work unit; wherein a temperature change and a time relationship between the core position and the peripheral position of the electrical system corresponds to a thermal impedance function, The electrical system estimates a thermal system parameter of the core position through temperature data of the peripheral position and the thermal impedance function. 12 . The electrical system of claim 11 , wherein the thermal system parameter at the core location corresponds to a transient thermal resistance. 13 . The electrical system of claim 11 , wherein the thermal system parameter at the core location corresponds to a temperature. 14 . The electrical system as claimed in claim 11 , wherein the electrical system performs overheat protection of the working unit and / or serves as a control parameter based on the thermal system parameter at the core position. 15 . The electrical system of claim 14 , wherein the thermal system parameter at the core location corresponds to a transient thermal resistance and temperature.

16. The electrical system of claim 11, wherein the input energy of the electrical system comprises an electrical energy input, and the working unit outputs the output energy under the control of a working condition of the working unit; in, The electrical system establishes an electrical system parameter by establishing a relationship between a key electrical characteristic of the working unit and a working condition. 17 . The electrical system as claimed in claim 16 , wherein the working unit evaluates the aging degree of a physical state of the core position by referring to the thermal system parameter and the electrical system parameter.

18. The electrical system of claim 16 , wherein the working unit compares the thermal system parameters using the thermal impedance function and the temperature data of the peripheral location, with reference to a working condition of the working unit, and compares the thermal system parameters obtained by computer-aided engineering with the electrical system parameters to evaluate a transient thermal resistance shift, thereby estimating the degree of aging of the working unit.

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