A single-voltage sensor module voltage detection method for a PSM high-voltage power supply

Abstract

The present application belongs to the technical field of high-voltage power supply, and specifically relates to a single-voltage sensor module voltage detection method for a PSM high-voltage power supply. The present application determines the target power module in the PWM modulation state through a PWM module cyclic control strategy, and uses a single voltage sensor to sample the voltage at the direct output end of the PSM high-voltage power supply, and obtains the voltage value of the target power module by calculating the difference of the sampled voltage signals. This method simplifies the hardware structure and reduces the cost. In addition, the present application also has overvoltage and undervoltage protection functions, monitors the voltage value of the power module and compares it with the preset threshold value, and performs protection actions such as locking the IGBT trigger signal and lighting the indicator light when an abnormality occurs, to ensure the safe operation of the system. The present application optimizes the detection method of the high-voltage power supply, enhances the safety and reliability of the system, and has wide application prospects and promotional value.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of high-voltage power supply, and particularly relates to a single-voltage sensor module voltage detection method of a PSM high-voltage power supply. BACKGROUND

[0002] The PSM high-voltage power supply is an important component of an Electron Cyclotron Resonance Heating (ECRH) system of a tokamak device. The PSM high-voltage power supply is obtained by connecting a large number of power supply modules in series to obtain the required high-voltage DC output. When the voltage of the power supply module is too high, an overvoltage state occurs. After the PSM high-voltage power supply is turned on, the load overshoots greatly, which may endanger the safety of the load. When the voltage of the power supply module is too low, an undervoltage state occurs, and the output of the high-voltage power supply cannot meet the load demand. Therefore, in order to ensure that the output voltage of the power supply module is within a safe and stable range and to ensure that the power supply system can work normally, overvoltage and undervoltage protection need to be performed. Voltage detection is a prerequisite for overvoltage and undervoltage protection. Usually, the PSM high-voltage power supply is composed of hundreds of power supply modules. The traditional detection method needs to use hundreds of voltage sensors to detect the voltage of the power supply module. On the one hand, this leads to high detection costs, and on the other hand, a large number of sensors are required for detection, and the overall reliability of the system is low. Therefore, how to reduce the number of required voltage sensors, reduce the voltage detection cost of the PSM high-voltage power supply, and improve the overall reliability of the system is an important problem in the voltage detection of the PSM high-voltage power supply. SUMMARY

[0003] The purpose of the present application is to provide a single-voltage sensor module voltage detection method of a PSM high-voltage power supply to solve the problem of a large number of voltage sensors required for module voltage detection of the existing PSM high-voltage power supply and high detection cost.

[0004] The present application achieves the above-mentioned purpose by the following technical solutions:

[0005] A single-voltage sensor module voltage detection method of a PSM high-voltage power supply, the PSM high-voltage power supply comprising a plurality of power supply modules and a signal generation module, the method comprising:

[0006] determining a target power supply module currently in a PWM modulation state according to a PWM module cyclic control strategy;

[0007] performing voltage sampling according to a voltage signal of a PSM high-voltage power supply direct output end voltage sensor and a set sampling mechanism to obtain a sampling voltage signal;

[0008] determining a voltage value of the target power supply module according to the sampling voltage signal;

[0009] The PWM module cyclically traverses each power supply module in the PSM high-voltage power supply and sequentially detects the voltage of each power supply module.

[0010] Further, the voltage sensor is connected in parallel to the direct output end of the PSM high-voltage power supply, and the voltage sensor is set to 1.

[0011] Further, the target power supply module currently in the PWM modulation state is determined according to the PWM module cyclic control strategy, including:

[0012] N-1 of the N power supply modules are set to a straight-through state, N is an integer greater than 1, and the remaining 1 is set to a PWM modulation state, and the straight-through signal (SM signal) and the PWM signal are controlled by the PWM module cyclic control unit to be switched between the power supply modules;

[0013] The cycle control signal of the PWM module cyclic control unit is read to determine the target power supply module currently in the PWM modulation state.

[0014] Further, the cycle control signal of the PWM module cyclic control unit is read to determine the target power supply module currently in the PWM modulation state, including:

[0015] The cycle control signal of the PWM module cyclic control unit is an N-bit binary coded signal, each bit corresponds to a power supply module, and the power supply module corresponding to the bit with a value of "1" in the output signal is the target power supply module.

[0016] Further, the voltage signal of the PSM high-voltage power supply direct output end voltage sensor and the set sampling mechanism are used to sample the voltage to obtain a sampled voltage signal, including:

[0017] The sampling time is determined by the PWM signal in the signal generation module, and the rising edge or falling edge of the PWM signal is detected in an interrupt mode;

[0018] After detecting the rising edge or falling edge of the PWM signal, a delay of a preset time t is performed to ensure that the switch tube of the detected target power supply module is in a conducting or blocking state;

[0019]

[0020] In the formula, D is the duty ratio of the PWM signal, and f is the switching frequency.

[0021] The analog voltage signal of the voltage sensor is read and converted into a digital voltage value by an analog-to-digital converter (ADC);

[0022] The digital voltage value includes a sampling voltage signal U2 collected after a delay t after detecting a rising edge of the PWM signal, and a sampling voltage signal U1 collected after a delay t after detecting a falling edge of the PWM signal.

[0023] Further, the voltage value of the target power module is determined according to the sampling voltage signal, including:

[0024] The difference between the sampling voltages U2 and U1 of the direct output end voltage signal of the PSM high-voltage power supply is taken as the voltage value of the target power module.

[0025] Further, the method further includes:

[0026] According to the voltage value of the target power module, the calculated voltage value is compared with a preset overvoltage and undervoltage threshold value, and if the voltage value of the power module exceeds the preset overvoltage or undervoltage threshold value, an overvoltage or undervoltage protection action is performed.

[0027] Further, the overvoltage or undervoltage protection action includes:

[0028] Latching an IGBT trigger signal;

[0029] Turning on a corresponding overvoltage or undervoltage indicator.

[0030] The beneficial effects of the present application are:

[0031] 1. The voltage detection circuit proposed in the present application only uses one voltage sensor, compared with the traditional PSM high-voltage power supply voltage detection method, greatly reducing the number of required voltage sensors, reducing the detection cost, and improving the reliability of the system. The detection method not only achieves its own detection purpose, but also takes into account the loss balance of the PSM high-voltage power supply, achieving two goals at once.

[0032] 2. The present application also has overvoltage and undervoltage protection functions. By monitoring the voltage value of the power module and comparing it with the preset threshold value, the system can quickly respond when the voltage is abnormal and perform corresponding protection actions, such as latching an IGBT trigger signal and turning on an indicator, thereby effectively preventing the power module from being damaged and ensuring the safe operation of the entire system. BRIEF DESCRIPTION OF DRAWINGS

[0033] Figure 1 A flowchart of the single-voltage sensor module voltage detection method of the PSM high-voltage power supply provided by the embodiments of the present application;

[0034] Figure 2 A voltage detection circuit diagram of the single-voltage sensor module voltage detection method of the PSM high-voltage power supply provided by the embodiments of the present application;

[0035] Figure 3 A schematic diagram of the signal generation module structure of the single voltage sensor module voltage detection method for the PSM high voltage power supply provided in the embodiments of this application;

[0036] Figure 4 A schematic diagram of the PWM power supply module determination in the single voltage sensor module voltage detection method of the PSM high voltage power supply provided in the embodiments of this application;

[0037] Figure 5 This is a schematic diagram of the voltage acquisition point in the single voltage sensor module voltage detection method of the PSM high voltage power supply provided in the embodiments of this application.

[0038] Figure 6 This is a schematic diagram of the voltage detection and over / under voltage protection method of the present invention. Detailed Implementation

[0039] The present application will now be described in further detail with reference to the accompanying drawings. It should be noted that the following specific embodiments are only used to further illustrate the present application and should not be construed as limiting the scope of protection of the present application. Those skilled in the art can make some non-essential improvements and adjustments to the present application based on the above application content.

[0040] like Figure 2 As shown, point A of the PSM high-voltage power supply is the direct output terminal. The voltage detection method of the single voltage sensor module of the PSM high-voltage power supply proposed in this invention refers to configuring a voltage sensor at point A of the direct output terminal of the PSM high-voltage power supply to replace the N voltage sensors on the low-voltage side of the power supply module in the traditional voltage detection method. The voltage signal of this voltage sensor is combined with the PWM module cyclic control strategy and voltage acquisition mechanism to detect the voltage of each power supply module.

[0041] Example 1

[0042] like Figures 1-6 As shown, this embodiment proposes a voltage detection method for a single voltage sensor module of a PSM (Pulse Step Modulation) high-voltage power supply. The PSM high-voltage power supply includes several power modules and a signal generation module. This detection method proposes a circuit that can complete the voltage detection of all power modules of the PSM high-voltage power supply using only one voltage sensor, and introduces the corresponding detection method and the power supply over- and under-voltage protection method.

[0043] Combination Figure 2 , Figure 3As shown, the voltage detection circuit includes: a voltage sensor and a signal processing unit; more specifically, the voltage sensor is connected in parallel to the direct output terminal of the PSM high-voltage power supply to collect the voltage signal of the direct output terminal of the PSM high-voltage power supply; the signal processing unit is used to determine the currently detected power module according to the loop control signal, convert the voltage sensor voltage signal into a digital voltage signal through ADC, determine the voltage acquisition point according to the PWM signal to obtain the U1 and U2 values, and finally calculate the voltage value of the current power module.

[0044] Explanation of PWM modulation principle: In a PSM high-voltage power supply, PWM modulation refers to controlling the switching state of the power module to cause the output voltage of the power module to exhibit a periodic change between high and low levels over time. This change can be adjusted by changing the proportion of high and low levels (i.e., the duty cycle) to regulate the average value of the output voltage, thereby achieving precise control of the power module's output voltage.

[0045] Combination Figure 1 As shown, the voltage detection method includes the following steps:

[0046] S1. Determine the target power supply module currently in PWM modulation state based on the PWM module's cyclic control strategy.

[0047] More specifically, N-1 of the N power modules are set to pass-through state, where N is an integer greater than 1, and the remaining 1 is set to PWM modulation state. The pass-through signal (marked as SM signal) and PWM signal are cyclically switched between the power modules by the PWM module cyclic control unit.

[0048] Read the loop control signal of the PWM module loop control unit to determine the target power module currently in PWM modulation state; the loop control signal of the PWM module loop control unit is an N-bit binary encoded signal, each bit corresponds to one power module, and the power module corresponding to the bit with a value of "1" in the output signal is the target power module.

[0049] S2. Based on the voltage sensor configured at the direct output terminal of the PSM high-voltage power supply and the set acquisition mechanism, voltage sampling is performed to obtain the sampled voltage signal.

[0050] S3. Determine the voltage value of the target power module based on the sampled voltage signal.

[0051] In a further optimized configuration, the PWM module iterates through each power module of the PSM high-voltage power supply, sequentially detecting all power modules.

[0052] In specific implementation, combined with Figures 3-5As shown, according to the PSM modulation principle, N-1 power modules work in the pass-through state, and the remaining one power module works in the PWM modulation state. Considering that the power module working in the PWM modulation state has relatively serious loss, a PWM module cycle control strategy needs to be designed.

[0053] The following takes a PSM high-voltage power supply composed of 6 power modules as an example to illustrate that the input of the cycle controller is provided by an SM control unit, a PWM control unit and a timing and bit number control unit. The output signal is sent to the drive circuit of each power module to control the turn-on and turn-off of each module.

[0054] The SM control unit provides N-1 power module control signals that need to pass through, collectively referred to as SM signals. The PWM control unit provides a PWM signal with a duty cycle of D. The timing and bit number control unit provides a binary coded signal to control the cycle of the PWM signal output. The timing and bit number control principle is to set the counting function f = 2 n , n is self-increased by 1 from 0 every interval T, and the interval T is the time interval for the PWM signal to switch from the previous power module to the next power module, and n is self-increased from 0 to 5 to complete a cycle. The counting function f is converted into a six-bit binary code as the cycle control signal output by the timing and bit number control unit.

[0055] The SM signals and the PWM signal are input into the cycle controller, and the cycle controller outputs the SM signals and the PWM signal according to a certain control rule according to the cycle control signal.

[0056] When the first power module works in the PWM modulation state, the signal corresponding to the PWM signal at this time is "1", and vice versa. For example, when the first power module works in the PWM modulation state, the counting function f is "2 0 ", which is converted into a binary code "000001", that is, the cycle control signal output by the timing and bit number control unit is "000001", and the cycle controller outputs the PWM signal as the first signal according to this signal, and the remaining 5 signals are SM signals; after the interval T, the PWM module is switched to the second power module, at this time the counting function f is "2 1 ", which is converted into a binary code "000010", and the cycle control signal output by the timing and bit number control unit is "000010", and the cycle controller outputs the PWM signal as the second signal according to this signal, and the remaining 5 signals are SM signals; in this way, finally the counting function f becomes 2 5 , and the cycle control signal becomes "100000", completing a cycle.

[0057] It should be noted that in the above scheme, N-bit binary coded signal: refers to the signal composed of N binary bits, each bit can be "0" or "1". For example, for 6 power modules, the cycle control signal can be "000001", "000010", etc.

[0058] It should be further noted that in the above scheme, each bit corresponds to a power module: each bit of the cycle control signal corresponds to a power module. For example, for 6 power modules, "000001" indicates that the current first power module is a PWM module, and "000010" indicates that the current second power module is a PWM module. The power module corresponding to the bit with value "1" in the cycle control signal is the power module currently in PWM modulation state.

[0059] Further preferably, in step S2, the voltage sampling is performed according to the voltage sensor voltage signal of the PSM high-voltage power supply direct output end and the set collection mechanism to obtain a sampling voltage signal, including:

[0060] The sampling time is determined by the PWM signal in the signal generating module, and the rising edge or falling edge of the PWM signal is detected in an interrupt mode;

[0061] After detecting the rising edge or falling edge of the PWM signal, a delay of a preset time t is performed to ensure that the switch tube of the detected target power module is in a conducting or blocking state;

[0062]

[0063] In the formula, D is the duty cycle of the PWM signal, and f is the switching frequency;

[0064] The analog voltage signal of the voltage sensor is read and converted into a digital voltage value;

[0065] The digital voltage value includes the sampling voltage signal U2 collected when the rising edge is detected, and the sampling voltage signal U1 collected when the falling edge is detected.

[0066] Further, the difference between the sampling voltage signals U2 and U1 of the PSM high-voltage power supply direct output end is taken as the voltage value of the target power module.

[0067] In combination Figure 5As shown, in combination with the PSM principle, the voltage U2 of the direct output end of the PSM high-voltage power supply is collected when the PWM power module (referring to the power module in the PWM modulation state) works in the high-level time (the rising edge delay t), at this time, the measured voltage U2 is the total voltage of all N power modules in series, the voltage U1 of the direct output end of the PSM high-voltage power supply is collected when the PWM power module works in the low-level time (the falling edge delay t), at this time, the measured voltage U1 is the total voltage of the remaining N-1 power modules in series except the PWM power module, and the difference between U2 and U1 is the voltage value corresponding to the PWM power module.

[0068] In the embodiment, the voltage collection mechanism is as follows:

[0069] The rising edge of the PWM signal is detected by the interrupt mode, and after the rising edge is detected, the delay t (D / 2f) is used to ensure that the switch tube is stably turned on, and the voltage sensor signal is converted into a voltage value by using the ADC. Similarly, the falling edge of the PWM signal is detected by the interrupt mode, and after the falling edge is detected, the delay t (D / 2f) is used to ensure that the switch tube is stably turned off, and the voltage sensor signal is converted into a voltage value by using the ADC. Finally, the read voltage value is stored.

[0070] Further preferably, the application further includes a power over-voltage and under-voltage protection method, which further includes: comparing the target power module voltage value calculated with the preset over-voltage and under-voltage threshold value, if the power module voltage value exceeds the preset over-voltage or under-voltage threshold value, performing an over-voltage or under-voltage protection action.

[0071] Further, the over-voltage or under-voltage protection action includes: locking the power module switch tube IGBT (Insulated Gate Bipolar Transistor, Insulated Gate Bipolar Transistor) trigger signal, and lighting the corresponding over-voltage or under-voltage indicator lamp.

[0072] In combination with Figure 6 As shown, according to the above scheme of the application, in the specific implementation, the following one implementable flow step is included:

[0073] Step 1: determining the power module currently in the PWM modulation state according to the PWM module cycle control strategy, that is, the currently detected power module.

[0074] Step 2: collecting the voltage values U1 and U2.

[0075] Step 3: calculating the voltage value to obtain the voltage of the current power module.

[0076] Step 4: overvoltage and undervoltage threshold judgment is performed, if the measured module voltage value exceeds the set overvoltage or undervoltage threshold, the power supply controller will perform IGBT trigger signal latching protection and turn on the corresponding overvoltage or undervoltage indicator. If the measured module voltage value is within the set overvoltage or undervoltage threshold, it indicates that the power module is working normally.

[0077] Step 5: the PWM signal is cycled to the next power module, and the above steps are repeated to detect all power modules in turn.

[0078] According to the above embodiments of the present application, the technical principle of the present application is to combine pulse width modulation (PWM) technology with step modulation (SM) technology. The present application uses PWM module cycle control strategy to set each power module in PWM modulation state in turn, and detects the voltage change at the direct output end of the PSM high-voltage power supply through a single voltage sensor. Since there is voltage pulsation in the direct output voltage of the PSM high-voltage power supply under PSM technology modulation, the voltage pulsation size is the voltage value of the power module, so the voltage values obtained by sampling at the high and low levels of the PWM signal will be different. By calculating the difference between the two sampling values, the voltage value of the target power module currently in PWM modulation state can be obtained.

[0079] Those skilled in the art can realize that the units and algorithm steps of the examples described in combination with the embodiments disclosed herein can be realized in electronic hardware or a combination of computer software and electronic hardware. Whether the functions are realized in hardware or software depends on the specific application and design constraints of the technical solution. A person skilled in the art can use different methods to realize the described functions for each specific application, but such implementation should not be considered beyond the scope of the present application.

[0080] In addition, the functional modules in each embodiment of the present application can be integrated in one processing unit, or each unit can exist physically alone, or two or more units can be integrated in one unit.

[0081] The above embodiments are only used to illustrate the technical solutions of the present application, and not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art can understand that the technical solutions recorded in the foregoing embodiments can be modified, or some technical features can be replaced by equivalents; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A single-voltage sensor module voltage detection method for a PSM high-voltage power supply, characterized in that, The PSM high-voltage power supply comprises a plurality of power supply modules and a signal generation module, and the method comprises: determining the target power supply module currently in the PWM modulation state according to the PWM module cycle control strategy, comprising: setting N-1 of the N power supply modules to a straight-through state, N being an integer greater than 1, and setting the remaining one to a PWM modulation state, and controlling the straight-through signal and the PWM signal to be switched between the power supply modules by a PWM module cycle control unit; reading the cycle control signal of the PWM module cycle control unit to determine the target power supply module currently in the PWM modulation state, comprising: the cycle control signal of the PWM module cycle control unit being an N-bit binary encoding signal, each bit corresponding to a power supply module, and the power supply module corresponding to the bit with a value of "1" in the output signal being the target power supply module; According to the voltage signal of the voltage sensor of the direct output end of the PSM high-voltage power supply and the set voltage acquisition mechanism, a voltage signal is sampled, including: determining a sampling time through a PWM signal in the signal generation module, and detecting the rising edge or falling edge of the PWM signal in an interrupt mode; after detecting the rising edge or falling edge of the PWM signal, delaying for a time t to ensure that the switch tube of the power supply module is in a conducting or blocking state; reading the analog voltage signal of the voltage sensor and converting it into a digital voltage value; wherein the digital voltage value includes a sampling voltage signal collected after delaying for t after detecting the rising edge of the PWM signal U 2, and a sampling voltage signal collected after delaying for t after detecting the falling edge of the PWM signal U 1; the voltage sensor is connected in parallel to the direct output end of the PSM high-voltage power supply, and the voltage sensor is set to one; According to the sampling voltage signal, the voltage value of the target power module is determined, including: taking the difference between the sampling voltage according to the PSM high-voltage power supply direct output end voltage signal and the sampling voltage according to the PSM high-voltage power supply direct output end voltage signal as the voltage value of the target power module U 2 and U 1 the PWM module cycles through the power supply modules in the PSM high-voltage power supply to detect the voltage of each power supply module in turn.

2. The single voltage sensor module voltage detection method of a PSM high voltage power supply according to claim 1, characterized in that, The method further comprises: comparing the calculated voltage value with preset overvoltage and undervoltage threshold values according to the voltage value of the target power supply module, and if the voltage value of the power supply module exceeds the preset overvoltage or undervoltage threshold value, performing an overvoltage or undervoltage protection action.

3. The single voltage sensor module voltage detection method of a PSM high voltage power supply according to claim 2, characterized in that, The overvoltage or undervoltage protection action comprises: locking an IGBT trigger signal; turning on a corresponding overvoltage or undervoltage indicator.

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