A full load range control method and control system for a rectangular wave pulse power supply

Abstract

The present application relates to a kind of rectangular wave pulse power full load range control method and control system;Existing pulse power control scheme cannot meet the problem of high dynamic high-precision full load range without overshoot requirement of high-end processing industry power supply;Method includes 1 determines rated amplitude, set standard rectangular wave pulse, and determines sampling frequency;2 control power supply main circuit output pulse waveform;3 continuously real-time sampling to pulse waveform;If sampling signal is amplitude, directly output;Otherwise, then output the amplitude signal of last acquisition, until the current period ends;3.2 compare sampling signal with rated amplitude, obtain comparison error;3.3 adjust comparison error, output continuous analog control quantity;3.4 continuous analog control quantity and standard rectangular wave pulse are intercepted with the way of logic " and " with, output pulse control signal, and send to power supply main circuit after being amplified;3.5 power supply main circuit output adjusted pulse waveform;3.6 repeat step 3.1-3.5.

Description

Technical Field

[0001] This invention relates to a rectangular wave pulse power supply, and more specifically to a method and control system for controlling the rectangular wave pulse power supply across its full load range. Background Technology

[0002] A pulsed power supply is a type of power supply that outputs a single or continuous pulse wave of a certain width and frequency. It can be either a voltage source or a current source and is generally used in industries such as semiconductor lasers and micro-arc oxidation. The output waveform is shown in the figure.

[0003] This type of power supply requires an approximately rectangular pulse wave output across the entire load range (i.e., from light load to full load), that is:

[0004] 1. The pulse rise is rapid and has no positive overshoot during the rise phase, and the pulse fall is rapid and has no negative overshoot during the fall phase;

[0005] 2. The faster the pulse rise and fall speeds, the better;

[0006] 3. The pulse discharge should be smooth and stable without overshoot, with high accuracy of the plateau value and low ripple.

[0007] 4. The pulse frequency, pulse width, and plateau value are continuously adjustable, and the waveform should approximate a rectangular wave across the entire load range from light load to full load.

[0008] Pulse power supplies commonly used in the market employ closed-loop control, directly sampling the output pulse quantity in real time. The sampled pulse quantity is compared with a given rectangular pulse waveform, and the comparison error is adjusted using PI or PID to control the power supply output. However, due to the delay (integral action) or overshoot (derivative action) in the response of PI or PID to pulse-type errors, the quality of the power supply output pulse waveform is poor, and the same set of control parameters is difficult to adapt to the requirement of no overshoot in the output waveform across the entire load range.

[0009] Currently, the mature commercial topologies for this type of power supply mainly consist of two solutions: multi-channel interleaved parallel BUCK switching technology and linear discharge technology for energy storage capacitors. The former is suitable for high-power pulse power supplies, while the latter is mostly used for low-power pulse power supplies. In terms of control strategy, both use PI (proportional-integral) or PID (proportional-integral-derivative) to directly modulate the pulse error. In PID control, the proportional element P can respond quickly to the error, the integral element I can eliminate steady-state error, and the derivative element D can respond to rapidly changing errors, but it is prone to overshoot.

[0010] When responding to rectangular pulse errors, the integral term I slows down the rise and fall slopes of the error due to the integral delay. Similarly, the derivative term D is prone to overshoot at the rise and fall edges of the pulse when responding to rectangular pulse errors. These characteristics lead to the following two problems when PI or PID controllers are used in pulse-type power supply control:

[0011] 1. It is difficult to control the power supply output pulse waveform to be approximately a rectangular wave. High pulse rise and fall slopes and no overshoot are contradictory requirements. To increase the pulse rise and fall slopes, the control loop gain needs to be increased. However, excessive control loop gain will inevitably lead to overshoot or control loop oscillation. If the control loop gain is reduced, waveform overshoot can be suppressed to some extent, but the pulse rise and fall slopes will not meet the requirements.

[0012] 2. Under the same set of control loop parameters, it is only possible to achieve a trade-off balance between the rising and falling slopes and overshoot within a very narrow load range. It is impossible to achieve the requirement of both high slope and no overshoot across the entire load range from light load to full load.

[0013] Based on the above two issues, pulse power supplies on the market that employ PI or PID modulation control strategies to directly modulate pulse errors have rise and fall slopes in the tens of A / ms to several A / μs range. Furthermore, these power supplies cannot achieve the requirement of zero overshoot across the entire load range, and waveform overshoot remains a persistent problem under light loads. However, some high-end, high-precision processing industries, such as semiconductor pulsed laser power supplies, require output pulse current rise and fall slopes of hundreds of A / μs or higher. Waveform overshoot can easily damage the laser semiconductor. Existing control strategies that directly modulate pulse errors using PI or PID modulation do not meet the high dynamic, high-precision, and zero-overshoot requirements of power supplies in these high-end processing industries across the entire load range. Summary of the Invention

[0014] The purpose of this invention is to solve the problem that existing pulse power supply control schemes cannot meet the high dynamic and high precision requirements of power supplies in the high-end processing industry for no overshoot across the entire load range. This invention provides a rectangular wave pulse power supply full load range control method and control system, which can achieve high slope requirements of hundreds of A / μs for the rise and fall of the pulse power supply, and ensure no overshoot across the entire load range from light load to full load. Furthermore, the output voltage / current values ​​are stable and highly accurate during the pulse plateau value period.

[0015] The design concept of this invention is as follows:

[0016] This invention samples the current / voltage signal output by the pulse power supply in real time. The sampled signal is sent to the amplitude holding circuit. If the sampled value sent to the amplitude holding circuit is the amplitude during the pulse output period, the output of the amplitude holding circuit is equal to the input. If the sampled value sent to the amplitude holding circuit is zero, the amplitude holding circuit continuously outputs the last amplitude sampled value until the end of the cycle.

[0017] The amplitude holding circuit converts the rectangular wave sampling signal in pulse form from the power supply output into an analog signal whose amplitude changes continuously. The continuously sampled signal after amplitude holding is compared with the rated amplitude setpoint signal of the pulse power supply to obtain the comparison error. The comparison error is then adjusted by a PI or PID controller to generate a continuous analog control quantity. This continuous analog control quantity is then truncated by a logical AND operation with a standard rectangular wave pulse signal with a given period and pulse width to generate an analog rectangular control quantity whose amplitude is adjusted in real time according to the continuous analog control quantity, but whose rising and falling edges are not adjusted by the PI or PID controller. After passing through the drive circuit, this is applied to the switching transistor of the main power supply circuit, making the main power supply circuit output an approximate rectangular wave.

[0018] Using the above methods, the PI or PID control circuit is only responsible for adjusting the plateau value of the output pulse waveform of the main power supply circuit, ensuring the accuracy of the output rectangular pulse wave plateau value. The rising and falling edge speeds of the pulse control signal are no longer regulated by the PI or PID controller, but are obtained by using the standard high-dynamic rectangular pulse waveform given signal to extract the amplitude analog control signal through AND logic. The rising and falling edges of the resulting rectangular pulse control signal are only related to the speed of the rectangular pulse given signal and the speed of the pulse control signal extraction circuit. Since the speed of the pulse control signal extraction circuit can be at the nanosecond level, this delay can be ignored, thus making the output of the main power supply circuit approximately a standard rectangular pulse wave. In steady state, whether under light or heavy load, due to the action of the integral element in the PI or PID controller, the pulse plateau value can be tracked without steady-state error, achieving the requirement of no overshoot across the entire load range.

[0019] The core of this invention lies in the fact that, in the control strategy, the amplitude modulation of the pulse error signal is completely decoupled from the rising and falling edge modulation, thus avoiding the problems of pulse head delay and overshoot caused by PI or PID directly modulating the pulse error signal. This control strategy can be used not only for pulse power supply systems, but also for the control methods of all other pulse-type output systems, and has wide applicability.

[0020] To achieve the above objectives, the technical solution of this invention is as follows:

[0021] A method for controlling a rectangular wave pulse power supply across its entire load range, characterized by the following steps:

[0022] Step 1: Determine the rated amplitude setpoint signal of the power supply output, set the standard rectangular wave pulse width and period setpoint signals, and determine the sampling frequency; the sampling frequency must be able to collect at least one set of pulse amplitude data within one cycle of the pulse power supply.

[0023] Step 2: Start Control

[0024] 2.1 Start the main power supply circuit and collect the output of the main power supply circuit to obtain the sampling signal;

[0025] 2.2 The sampled signal from step 2.1 is amplitude held and then compared with the rated amplitude given signal output by the power supply to obtain the comparison error;

[0026] 2.3 After adjusting the comparison error in step 2.2 using a PI or PID controller, output a continuous analog control quantity;

[0027] 2.4 The continuous analog control quantity obtained in step 2.3 and the standard rectangular wave pulse given signal in step 1 are truncated by logical AND, and the pulse control signal is output. The amplified drive signal of the pulse control signal is then sent to the main power supply circuit.

[0028] 2.5 After receiving the drive signal from step 2.4, the main power supply circuit outputs a pulse waveform;

[0029] Step 3: Loop Control

[0030] 3.1 The pulse waveform output by the main power supply circuit is continuously sampled in real time to obtain the sampled signal; if the sampled signal is the amplitude during the pulse output period, it is output directly; otherwise, the sampled signal of the amplitude of the last acquisition is output until the end of the current cycle.

[0031] 3.2 Compare the sampled signal output in step 3.1 with the rated amplitude given signal output by the power supply to obtain the comparison error;

[0032] 3.3 After adjusting the comparison error using a PI or PID controller, a continuous analog control quantity is output;

[0033] 3.4 The continuous analog control quantity obtained in step 3.3 and the standard rectangular wave pulse given signal in step 1 are truncated by logical AND, and a pulse control signal is output. The amplified drive signal of the pulse control signal is sent to the main power supply circuit. The amplitude of the pulse control signal output in steps 2.4 and 3.4 is the same as that of the continuous analog control quantity, and the pulse width, period, rise slope and fall slope are the same as those of the standard rectangular wave pulse.

[0034] 3.5 After receiving the drive signal, the main power supply circuit outputs the adjusted pulse waveform;

[0035] 3.6 Repeat steps 3.1-3.5 to perform real-time control of the rectangular wave pulse power supply across the entire load range.

[0036] The present invention also proposes a rectangular wave pulse power supply full load range control system. In order to realize the above-mentioned rectangular wave pulse power supply full load range control method, it includes a power supply main circuit, which is special in that it also includes a control circuit.

[0037] The control circuit includes a pulse sampling circuit, an amplitude holding circuit, an error comparison circuit, a PID or PI adjustment circuit, a pulse control signal interception circuit, a pulse amplitude setting circuit, a standard pulse setting circuit, and a drive circuit.

[0038] The input terminal of the pulse sampling circuit is connected to the output terminal of the main power supply circuit. The output terminal of the pulse sampling circuit is connected to the input terminal of the amplitude holding circuit. The output terminal of the amplitude holding circuit is connected to the first input terminal of the error comparison circuit. The output terminal of the error comparison circuit is connected to the input terminal of the PID or PI regulation circuit. The output terminal of the PID or PI regulation circuit is connected to the first input terminal of the pulse control signal interception circuit. The output terminal of the pulse control signal interception circuit is connected to the input terminal of the drive circuit. The output terminal of the drive circuit is connected to the control terminal of the switching transistor in the main power supply circuit. The output terminal of the standard pulse setting circuit is connected to the second input terminal of the pulse control signal interception circuit and is used to send a standard rectangular wave pulse to the pulse control signal interception circuit. The output terminal of the pulse amplitude setting circuit is connected to the second input terminal of the error comparison circuit and is used to send the rated amplitude of the pulse wave output by the power supply to the error comparison circuit.

[0039] The pulse sampling circuit samples the output of the main power supply circuit and outputs the sampled signal to the amplitude holding circuit. The amplitude holding circuit holds the received sampled signal and outputs it to the error comparison circuit. The error comparison circuit compares the received sampled signal with the rated amplitude and outputs the comparison error to the PID or PI adjustment circuit. The PID or PI adjustment circuit adjusts the received comparison error and outputs a continuous analog control quantity to the pulse control signal interception circuit. The pulse control signal interception circuit performs a logical AND operation between the received continuous analog control quantity and a standard rectangular wave pulse and outputs a pulse control signal to the drive circuit. The drive circuit amplifies the received pulse control signal and outputs a drive signal to the control terminal of the switching transistor in the main power supply circuit to control the output pulse waveform of the main power supply circuit.

[0040] Furthermore, the amplitude holding circuit is implemented using digital circuitry or analog circuitry.

[0041] Furthermore, the amplitude holding circuit is implemented using analog circuitry, including a second diode, a second resistor, and a second capacitor;

[0042] The anode of the second diode is connected to the output terminal of the pulse sampling circuit, the cathode of the second diode is connected to one end of the second capacitor, the other end of the second capacitor is grounded, the second resistor is connected in parallel with the second capacitor, and the cathode of the second diode is connected to the first input terminal of the error comparison circuit.

[0043] Furthermore, the pulse control signal interception circuit uses a second MOSFET. The gate (G) of the second MOSFET is connected to the output terminal of the standard pulse setpoint circuit, the drain (D) of the second MOSFET is connected to the output terminal of the PID or PI adjustment circuit, and the source (S) of the second MOSFET is connected to the input terminal of the drive circuit.

[0044] Furthermore, the pulse sampling circuit is an operational amplifier or a current Hall effect sensor; the non-inverting input terminal of the operational amplifier or current Hall effect sensor is connected to one end of the sampling resistor, the inverting input terminal of the operational amplifier or current Hall effect sensor is connected to the other end of the sampling resistor, and the output terminal of the operational amplifier or current Hall effect sensor is connected to the anode of the second diode.

[0045] Furthermore, the PID / PI regulation circuit includes a PI circuit and a D circuit. The input terminal of the PI circuit is connected to the output terminal of the error comparison circuit, and the output terminal of the PI circuit is connected to the drain stage of the second MOSFET. The D circuit is connected in parallel with the PI circuit.

[0046] Furthermore, the control circuit also includes an auxiliary power supply circuit;

[0047] The auxiliary power supply circuit is used to provide operating power for the pulse sampling circuit, amplitude holding circuit, error comparison circuit, PID or PI adjustment circuit, pulse control signal interception circuit, pulse amplitude setting circuit, standard pulse setting circuit, and drive circuit.

[0048] Furthermore, the driving circuit includes a first resistor and a third resistor;

[0049] One end of the first resistor is connected to the source (S) terminal of the second MOSFET, and the other end is connected to the gate (G) terminal of the switching transistor in the main power supply circuit.

[0050] One end of the third resistor is connected to one end of the first resistor, and the other end is grounded.

[0051] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0052] 1. The control method in this invention decouples the control of rectangular pulse amplitude from the control of waveform quality (rise rate, fall rate, duty cycle, frequency), which not only achieves the high slope requirements of pulse power supply rise and fall of up to hundreds of A / μs, but also ensures no pulse overshoot across the entire load range from light load to full load. Furthermore, the output voltage / current values ​​are stable and highly accurate during the pulse plateau period. This solves the problem that existing control strategies that directly modulate pulse errors using PI or PID cannot meet the high dynamic and high precision requirements of power supplies in high-end processing industries for no overshoot across the entire load range.

[0053] 2. In this invention, PI or PID only adjusts the continuous analog error signal and does not adjust the highly dynamic rectangular pulse error signal. The difficulty of matching the control parameters of the PI or PID adjustment circuit with the changes of the main power supply circuit parameters and load parameters is greatly reduced, which can avoid the problem of oscillation in the control loop caused by high gain control parameters.

[0054] 3. In this invention, the rising and falling edge speeds of the final output analog pulse control signal are only related to the action time of the pulse control signal interception circuit, and are not related to the type and control parameters of the PI or PID adjustment circuit, nor to the magnitude of the output voltage or current plateau value. Therefore, it can meet the requirement of outputting an approximate rectangular wave across the entire load range of the pulse power supply.

[0055] 4. In this invention, PI or PID modulates the amplitude signal of a continuous analog pulse, but does not modulate the rectangular pulse signal, thus achieving strict overshoot-free operation across the entire load range.

[0056] 5. The control method proposed in this invention can be used in both linear power supply main circuits and switching power supply main circuits, such as BUCK type, and can also be widely used in various pulse output systems, such as some pulse motor drive systems.

[0057] 6. The control method of this invention can be implemented using either hardware circuits or software solutions, which is flexible and convenient, and can greatly improve the output waveform quality of this type of pulse power supply.

[0058] 7. The control method of this invention does not require complex algorithms or analog circuits to be implemented. It is simple in principle and convenient to use. Attached Figure Description

[0059] Figure 1 This is a schematic diagram of a rectangular wave output by a pulse power supply, where T represents the period of the pulse power supply, the horizontal axis t represents time, and the vertical axis represents the rated voltage U or rated current I of the pulse power supply.

[0060] Figure 2 Here is the schematic diagram of an existing linear pulse current source control system;

[0061] Figure 3 for Figure 2 Simulation scheme;

[0062] Figure 4 This is a schematic diagram of the linear pulse current source control system according to an embodiment of the present invention;

[0063] Figure 5 for Figure 4 Simulation scheme;

[0064] Figure 6 This is a schematic diagram of the amplitude holding analog circuit in an embodiment of the present invention;

[0065] Figure 7 The diagram shows the effect of the existing control scheme under a 400A heavy load output, where the horizontal axis t represents time and the vertical axis represents the output current I of the pulse current source.

[0066] Figure 8 The diagram shows the effect of the control scheme of this invention under a heavy load of 400A output. In the diagram, the horizontal axis t represents time and the vertical axis represents the output current I of the pulse current source.

[0067] Figure 9 The diagram shows the effect of the existing control scheme under a light load of 10A output, where the horizontal axis t represents time and the vertical axis represents the output current I of the pulse current source.

[0068] Figure 10 The diagram shows the effect of the control scheme of this invention under a light load of 10A output, where the horizontal axis t represents time and the vertical axis represents the output current I of the pulse current source.

[0069] Figures 1-3 In the middle section: 01. Main power supply circuit; 02. Control circuit; 022. Error comparison circuit; 023. PID or PI adjustment circuit; 025. Drive circuit; 026. Pulse sampling circuit; 027. Standard pulse setpoint circuit;

[0070] Figures 4-6 In the circuit: 1. Main power supply circuit; 11. Input power supply; 12. First capacitor; 13. Switching transistor; 14. First diode; 15. Load; 16. Sampling resistor; 2. Control circuit; 21. Amplitude holding circuit; 211. Second diode; 212. Second resistor; 213. Second capacitor; 22. Error comparison circuit; 23. PID or PI adjustment circuit; 24. Pulse control signal interception circuit; 25. Drive circuit; 26. Pulse sampling circuit; 27. Standard pulse setting circuit; 28. Pulse amplitude setting circuit. Detailed Implementation

[0071] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0072] Existing pulse power supply control schemes such as Figure 2 and Figure 3 As shown, the circuit includes a main power supply circuit 01 and a control circuit 02. The control circuit 02 includes an error comparison circuit 022, a PID or PI adjustment circuit 023, a drive circuit 025, a pulse sampling circuit 026, and a standard pulse setpoint circuit 027. The pulse waveform output by this power supply control scheme has two problems: first, there is overshoot at the rising and falling edges of the pulse waveform; second, the slope of the rising and falling edges of the pulse waveform is significantly reduced.

[0073] To address the aforementioned problems, this invention proposes a rectangular wave pulse power supply full-load range control system, such as... Figure 4 and Figure 5 As shown, it includes a main power supply circuit 1 and a control circuit 2. The control circuit 2 is used to adjust the plateau value and waveform quality of the pulse waveform output by the pulse power supply. Under the control of the control circuit 2, the main power supply circuit 1 outputs a pulse waveform, resulting in an approximate rectangular wave pulse output by the main power supply circuit 1 across the full load range.

[0074] Control circuit 2 includes an auxiliary power supply circuit, a pulse sampling circuit 26, an amplitude holding circuit 21, an error comparison circuit 22, a PID or PI adjustment circuit 23, a pulse control signal interception circuit 24, a pulse amplitude setting circuit 28, a standard pulse setting circuit 27, and a drive circuit 25; the pulse sampling circuit 26 uses a sampling operational amplifier, and the pulse control signal interception circuit 24 uses a second MOSFET.

[0075] The main power supply circuit 1 includes an input power supply 11, a first capacitor 12, a switching transistor 13, a load 15, a first diode 14, and a sampling resistor 16. The switching transistor 13 is a first MOSFET, and the load 15 is a light-emitting diode.

[0076] One end of the first capacitor 12 is connected to the positive terminal of the input power supply 11, and the other end is connected to the negative terminal of the input power supply 11; the cathode of the first diode 14 is connected to the positive terminal of the input power supply 11, the anode of the first diode 14 is connected to the drain (D) terminal of the first MOSFET, the source (S) terminal of the first MOSFET is connected to the negative terminal of the input power supply 11, the anode of the light-emitting diode (LED) is connected to the positive terminal of the input power supply 11, the cathode of the LED is connected to one end of the sampling resistor 16, the other end of the sampling resistor 16 is connected to the drain (D) terminal of the first MOSFET, the non-inverting input terminal of the operational amplifier (op-amp) is connected to one end of the sampling resistor 16, the inverting input terminal of the op-amp is connected to the other end of the sampling resistor 16, and the output terminal of the op-amp is connected to the amplitude-maintaining terminal. The input terminal of the amplitude holding circuit 21 is connected to the input terminal of the error comparison circuit 22. The output terminal of the error comparison circuit 22 is connected to the input terminal of the PI or PID adjustment circuit 23. The output terminal of the PI or PID adjustment circuit 23 is connected to the drain (D) terminal of the second MOSFET. The gate (G) terminal of the second MOSFET is connected to the output terminal of the standard pulse setting circuit 27. The source (S) terminal of the second MOSFET is connected to the input terminal of the drive circuit 25. The output terminal of the drive circuit 25 is connected to the gate (G) terminal of the first MOSFET. The pulse amplitude setting circuit 28 is connected to the input terminal of the error comparison circuit 22. The standard pulse setting circuit 27 is connected to the gate (G) terminal of the second MOSFET.

[0077] The input terminal of the auxiliary power supply circuit is connected to the input power supply 11, and the output terminal of the auxiliary power supply circuit is connected to the pulse sampling circuit 26, the amplitude holding circuit 21, the error comparison circuit 22, the PID or PI adjustment circuit 23, the pulse control signal interception circuit 24, the pulse amplitude setting circuit 28, the standard pulse setting circuit 27, and the drive circuit 25. It is used to provide working power to the pulse sampling circuit 26, the amplitude holding circuit 21, the error comparison circuit 22, the PID or PI adjustment circuit 23, the pulse control signal interception circuit 24, the pulse amplitude setting circuit 28, the standard pulse setting circuit 27, and the drive circuit 25.

[0078] The advantage of using a second MOSFET in the pulse control signal interception circuit 24 is its fast switching speed.

[0079] The amplitude holding circuit 21 can be implemented using digital circuitry or analog circuitry, such as... Figure 6 As shown, this embodiment provides an analog circuit structure. The amplitude holding circuit 21 is implemented using an analog circuit, including a second diode 211, a second resistor 212, and a second capacitor 213. The anode of the second diode 211 is connected to the output terminal of the pulse sampling circuit 26, the cathode of the second diode 211 is connected to one end of the second capacitor 213, the other end of the second capacitor 213 is grounded, the second resistor 212 is connected in parallel with the second capacitor 213, and the cathode of the second diode 211 is connected to the input terminal of the error comparison circuit 22.

[0080] In this embodiment, the driving circuit 25 includes a first resistor and a third resistor; one end of the first resistor is connected to the source (S) terminal of the second MOS transistor, and the other end is connected to the gate (G) terminal of the switching transistor 13 in the main power supply circuit 1; one end of the third resistor is connected to one end of the first resistor, and the other end is grounded.

[0081] Based on the above control circuit, this invention also proposes a method for controlling a rectangular wave pulse power supply across the entire load range, comprising the following steps:

[0082] Step 1: Determine the rated amplitude setpoint signal of the power supply output, set the standard rectangular wave pulse width and period setpoint signals, and determine the sampling frequency; the sampling frequency must be able to collect at least one set of pulse amplitude data within one cycle of the pulse power supply.

[0083] Step 2: Start Control

[0084] 2.1 Powering the input power supply starts the main power supply circuit 1, and at the same time, the auxiliary power supply circuit starts to power the entire control circuit; the operational amplifier collects the output of the main power supply circuit 1, which is 0, and obtains the sampling signal.

[0085] 2.2 The sampling signal acquired in step 2.1 is held by the amplitude holding circuit 21 and then sent to the error comparison circuit 22. The error comparison circuit 22 compares the received sampling signal with the rated amplitude of the power supply output to obtain the comparison error.

[0086] 2.3 The comparison error in step 2.2 is adjusted by the PI or PID adjustment circuit 23, and the continuous analog control quantity is output to the pulse control signal interception circuit 24;

[0087] 2.4 The pulse control signal interception circuit 24 intercepts the received continuous analog control quantity with a standard rectangular wave pulse (with unchanged amplitude) of set rated duty cycle and frequency using a logical "AND" method, generating a pulse control signal with the same pulse width, frequency, and rise and fall slope as the standard rectangular wave pulse reference, but with the same amplitude as the continuous analog control quantity obtained in step 2.3. The pulse control signal is then output to the drive circuit 25. The drive circuit 25 amplifies the pulse control signal and outputs a drive signal to the switching transistor 13 of the main power supply circuit 1.

[0088] 2.5 After receiving the drive signal in step 2.4, the switching transistor 13 of the main power supply circuit 1 controls the main power supply circuit 1 to output a pulse waveform;

[0089] Step 3: Loop Control

[0090] 3.1 The pulse sampling circuit 26 continuously samples the pulse waveform output by the main power supply circuit 1 in real time to obtain the sampled signal and sends it to the amplitude holding circuit 21. If the sampled signal is the amplitude during the pulse output period, the output of the amplitude holding circuit 21 is equal to the input, that is, the amplitude holding circuit 21 outputs directly. Otherwise, if the sampled value sent to the amplitude holding circuit 21 is zero, the amplitude holding circuit 21 outputs the last sampled signal with the amplitude value to the error comparison circuit 22 until the end of the current cycle.

[0091] After the amplitude holding circuit 21, the rectangular sampling signal of the power supply output pulse is transformed into a continuous sampling signal that varies with the pulse amplitude. If the amplitude holding circuit 21 is implemented digitally, the higher the operation frequency of the digital circuit, the faster the dynamic adjustment characteristics of the pulse power supply.

[0092] 3.2 The error comparison circuit 22 compares the received sampled signal with the rated amplitude of the power supply output to obtain the comparison error;

[0093] 3.3 After adjusting the comparison error through PI or PID control circuit 23, a continuous analog control quantity is output;

[0094] 3.4 The pulse control signal interception circuit 24 intercepts the received continuous analog control quantity with a standard rectangular wave pulse (with unchanged amplitude) of set rated duty cycle and frequency using a logical "AND" method, generating a pulse control signal with the same pulse width, frequency, and rise and fall slope as the standard rectangular wave pulse reference, but with the same amplitude as the continuous analog control quantity obtained in step 3.3. The pulse control signal is output to the drive circuit 25. The drive circuit 25 amplifies the pulse control signal and outputs a drive signal to the switching transistor 13 of the main power supply circuit 1.

[0095] The "AND" logic method for truncation refers to the following: when the standard rectangular wave pulse is given as 1, the output of the pulse control signal truncation circuit 24 is the same as the PI or PID output value; when the standard rectangular wave pulse is 0, the output value of the pulse control signal truncation circuit 24 is 0. Thus, by truncation of the obtained continuous analog control quantity through the above "AND" logic method, a rectangular pulse control signal with a high rising slope and a high falling slope can be obtained.

[0096] 3.5 After receiving the drive signal, the main power supply circuit 1 outputs the adjusted pulse waveform;

[0097] 3.6 Repeat steps 3.1-3.5 to perform real-time control of the rectangular wave pulse power supply across the entire load range;

[0098] If control circuit 2 is implemented using analog circuits, the above process is carried out continuously in real time; if control circuit 2 is implemented using digital circuits, the above process is carried out at the frequency calculated by the digital circuits.

[0099] To demonstrate the effectiveness of this invention, a simulation comparison was conducted using the same power supply main circuit and PID control parameters, based on a linear current source main circuit, to compare the effects of the two control methods. The results are as follows: Figure 7-10 As shown, from Figure 7 and Figure 9 As can be seen from this, regardless of whether it is under light load or heavy load, the existing control scheme results in two issues with the final output load pulse current: first, there is overshoot at the rising and falling edges; second, the slope of the rising and falling edges decreases significantly, that is, the rising or falling speed gradually decreases.

[0100] from Figure 8 and Figure 10 As can be seen, regardless of whether it is under light or heavy load, the control scheme of the present invention results in a load pulse current that does not have overshoot or significant slope reduction at the rising and falling edges. That is, the rising or falling edge always maintains a large speed, making the output approximately a rectangular wave.

Claims

1. A method for controlling a rectangular wave pulse power supply across its entire load range, characterized in that, Includes the following steps: Step 1: Determine the rated amplitude setpoint signal of the power supply output, set the standard rectangular wave pulse width and period setpoint signals, and determine the sampling frequency; the sampling frequency must be able to collect at least one set of pulse amplitude data within one cycle of the pulse power supply. Step 2: Start Control 2.1 Start the main power supply circuit (1) and collect the output of the main power supply circuit (1) to obtain the sampling signal; 2.2 The sampled signal from step 2.1 is amplitude held and then compared with the rated amplitude given signal output by the power supply to obtain the comparison error; 2.3 After adjusting the comparison error in step 2.2 using a PI or PID controller, output a continuous analog control quantity; 2.4 The continuous analog control quantity obtained in step 2.3 and the standard rectangular wave pulse given signal in step 1 are extracted by logical AND, and the pulse control signal is output. The amplified drive signal of the pulse control signal is sent to the main power supply circuit (1). 2.5 Power supply main circuit (1) After receiving the drive signal in step 2.4, it outputs a pulse waveform; Step 3: Loop Control 3.1 The pulse waveform output by the main power circuit (1) is continuously sampled in real time to obtain the sampling signal; if the sampling signal is the amplitude during the pulse output period, it is directly output; otherwise, the sampling signal of the amplitude of the last acquisition is output until the end of the current cycle. 3.2 Compare the sampled signal output in step 3.1 with the rated amplitude given signal output by the power supply to obtain the comparison error; 3.3 After adjusting the comparison error using a PI or PID controller, a continuous analog control quantity is output; 3.4 The continuous analog control quantity obtained in step 3.3 and the standard rectangular wave pulse given signal in step 1 are extracted by logical AND, and the pulse control signal is output. The amplified drive signal of the pulse control signal is sent to the main power supply circuit (1). 3.5 Power supply main circuit (1) After receiving the drive signal, it outputs the adjusted pulse waveform; 3.6 Repeat steps 3.1-3.5 to perform real-time control of the rectangular wave pulse power supply across the entire load range.

2. A rectangular wave pulse power supply full load range control system, in order to realize the rectangular wave pulse power supply full load range control method as described in claim 1, includes a power supply main circuit (1), characterized in that: it further includes a control circuit (2); The control circuit (2) includes a pulse sampling circuit (26), an amplitude holding circuit (21), an error comparison circuit (22), a PID or PI adjustment circuit (23), a pulse control signal interception circuit (24), a pulse amplitude setting circuit (28), a standard pulse setting circuit (27), and a drive circuit (25). The input terminal of the pulse sampling circuit (26) is connected to the output terminal of the main power supply circuit (1), the output terminal of the pulse sampling circuit (26) is connected to the input terminal of the amplitude holding circuit (21), the output terminal of the amplitude holding circuit (21) is connected to the first input terminal of the error comparison circuit (22), the output terminal of the error comparison circuit (22) is connected to the input terminal of the PID or PI adjustment circuit (23), the output terminal of the PID or PI adjustment circuit (23) is connected to the first input terminal of the pulse control signal interception circuit (24), and the pulse control signal interception circuit (26) is connected to the first input terminal of the pulse control signal interception circuit (24). The output terminal of 4) is connected to the input terminal of the drive circuit (25), and the output terminal of the drive circuit (25) is connected to the control terminal of the switching transistor (13) in the main power supply circuit (1); the output terminal of the standard pulse setting circuit (27) is connected to the second input terminal of the pulse control signal interception circuit (24) and is used to send a standard rectangular wave pulse to the pulse control signal interception circuit (24); the output terminal of the pulse amplitude setting circuit (28) is connected to the second input terminal of the error comparison circuit (22) and is used to send the rated amplitude of the pulse wave output by the power supply to the error comparison circuit (22); The pulse sampling circuit (26) samples the output of the main power circuit (1) and outputs the sampled signal to the amplitude holding circuit (21). The amplitude holding circuit (21) outputs the received sampled signal to the error comparison circuit (22) after amplitude holding. The error comparison circuit (22) compares the received sampled signal with the rated amplitude and outputs the comparison error to the PID or PI adjustment circuit (23). The PID or PI adjustment circuit (23) adjusts the received comparison error and outputs the continuous analog control quantity to the pulse control signal interception circuit (24). The pulse control signal interception circuit (24) intercepts the received continuous analog control quantity with the standard rectangular wave pulse in a logical AND manner and outputs the pulse control signal to the drive circuit (25). The drive circuit (25) amplifies the received pulse control signal and outputs the drive signal to the control terminal of the switching transistor (13) in the main power circuit (1) to control the output pulse waveform of the main power circuit (1).

3. The rectangular wave pulse power supply full load range control system according to claim 2, characterized in that: The amplitude holding circuit (21) is implemented using digital circuitry or analog circuitry.

4. The rectangular wave pulse power supply full load range control system according to claim 3, characterized in that: The amplitude holding circuit (21) is implemented using analog circuitry, including a second diode (211), a second resistor (212), and a second capacitor (213); The anode of the second diode (211) is connected to the output terminal of the pulse sampling circuit (26), the cathode of the second diode (211) is connected to one end of the second capacitor (213), the other end of the second capacitor (213) is grounded, the second resistor (212) is connected in parallel with the second capacitor (213), and the cathode of the second diode (211) is connected to the first input terminal of the error comparison circuit (22).

5. A rectangular wave pulse power supply full load range control system according to any one of claims 2-4, characterized in that: The pulse control signal interception circuit (24) uses a second MOS transistor. The gate (G) of the second MOS transistor is connected to the output terminal of the standard pulse setpoint circuit (27), the drain (D) of the second MOS transistor is connected to the output terminal of the PID or PI adjustment circuit (23), and the source (S) of the second MOS transistor is connected to the input terminal of the drive circuit (25).

6. The rectangular wave pulse power supply full load range control system according to claim 5, characterized in that: The pulse sampling circuit (26) is an operational amplifier or a current Hall effect sensor; the non-inverting input terminal of the operational amplifier or current Hall effect sensor is connected to one end of the sampling resistor (16), the inverting input terminal of the operational amplifier or current Hall effect sensor is connected to the other end of the sampling resistor (16), and the output terminal of the operational amplifier or current Hall effect sensor is connected to the anode of the second diode (211).

7. A rectangular wave pulse power supply full load range control system according to claim 6, characterized in that: The PID / PI control circuit includes a PI circuit and a D circuit. The input terminal of the PI circuit is connected to the output terminal of the error comparison circuit, and the output terminal of the PI circuit is connected to the drain stage of the second MOSFET. The D circuit is connected in parallel with the PI circuit.

8. A rectangular wave pulse power supply full load range control system according to claim 7, characterized in that: The control circuit (2) also includes an auxiliary power supply circuit; The auxiliary power supply circuit is used to provide operating power for the pulse sampling circuit (26), amplitude holding circuit (21), error comparison circuit (22), PID or PI adjustment circuit (23), pulse control signal interception circuit (24), pulse amplitude setting circuit (28), standard pulse setting circuit (27) and drive circuit (25).

9. A rectangular wave pulse power supply full load range control system according to claim 8, characterized in that: The driving circuit (25) includes a first resistor and a third resistor; One end of the first resistor is connected to the source (S) terminal of the second MOSFET, and the other end is connected to the gate (G) terminal of the switching transistor (13) in the main power supply circuit (1). One end of the third resistor is connected to one end of the first resistor, and the other end is grounded.

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