Pulsed magnetic field stimulator high frequency output voltage control circuit

Abstract

The utility model discloses a kind of high-frequency output voltage control circuit of pulsed magnetic field stimulator, it belongs to the field of pulse therapy, it can have stable magnetic field output control, and it has the function of high-frequency stimulation output, can satisfy the stable magnetic stimulation output above 0.1Hz-200Hz.It mainly includes high-voltage generating circuit and high-voltage rectifier circuit, the high-voltage generating circuit and high-voltage rectifier circuit are connected by inverter boost circuit, inverter boost circuit connection includes transformer L1, the low-voltage side of transformer L1 is connected with the D pole of MOS tube Q1 respectively, the D pole of MOS tube Q2, the S pole of MOS tube Q3 and the S pole of MOS tube Q4, the G pole of MOS tube Q1 and the G pole of MOS tube Q4 are all connected with PWM1, the G pole of MOS tube Q2 and the G pole of MOS tube Q3 are all connected with PWM2.The utility model is mainly used for pulsed magnetic field stimulator.

Description

Technical Field

[0001] This utility model relates to the field of pulse therapy, and more specifically, to a high-frequency output voltage control circuit for a pulse magnetic field stimulator. Background Technology

[0002] With socio-economic development and the aging population, rehabilitation is receiving increasing attention. Magnetotherapy products, as a fundamental type of physical therapy, have always been essential treatment equipment in medical institutions. Pulsed magnetic field stimulators, based on Faraday's law of electromagnetic induction, generate pulsed magnetic fields through magnetic field coils, directly acting on specific areas of the cerebral cortex. When the human head is exposed to a time-varying magnetic field, induced currents or eddy currents are generated within the tissues. These induced currents further alter the transmembrane potential of cell membranes, causing cell membrane depolarization and thus activating nerve tissue. This method achieves non-invasive stimulation of the cerebral cortex, thereby regulating and altering brain function. Currently, most devices on the market have relatively low stimulation frequencies, ranging from 1-100Hz, which cannot meet higher requirements. Utility Model Content

[0003] The purpose of this invention is to provide a high-frequency output voltage control circuit for a pulse magnetic field stimulator, which has the function of stable magnetic field output control and high-frequency stimulation output, and can meet the stable magnetic stimulation output of 0.1Hz-200Hz and above.

[0004] This utility model is achieved through the following technical solution:

[0005] A high-frequency output voltage control circuit for a pulsed magnetic field stimulator includes a high-voltage generating circuit and a high-voltage rectifier circuit. The high-voltage generating circuit and the high-voltage rectifier circuit are connected via an inverter boost circuit. The inverter boost circuit includes a transformer L1. The low-voltage side of the transformer L1 is connected to the drain (D) of MOSFET Q1, the drain (D) of MOSFET Q2, the source (S) of MOSFET Q3, and the source (S) of MOSFET Q4. The gate (G) of MOSFET Q1 and the gate (G) of MOSFET Q4 are both connected to PWM1, and the gate (G) of MOSFET Q2 and the gate (G) of MOSFET Q3 are both connected to PWM2. PWM1 and PWM2 are two PWM waves generated diagonally with a phase difference of 180°. The source (S) of MOSFET Q1 and the source (S) of MOSFET Q2 are connected to the high-voltage generating circuit. The high-voltage side of the transformer L1 is connected to the high-voltage rectifier circuit. The capacitor C1 of the high-voltage rectifier circuit is connected to a high-voltage discharge circuit.

[0006] Furthermore, the high-voltage generating circuit includes a rectifier bridge T1, with a filter capacitor C29, a resistor R1, and a filter capacitor C30 connected in parallel at the output terminals of the rectifier bridge T1. The source terminals of MOSFET Q1 and MOSFET Q2 are connected to the filter capacitor C30. The AC mains power is rectified, and the 220V AC power is rectified into 300V DC power through the rectification and filtering of the rectifier bridge T1 and the filter capacitors C29 and C30.

[0007] Furthermore, the high-voltage rectifier circuit includes a rectifier bridge T2, the input terminal of which is connected to the high-voltage side of the transformer L1, and the output terminal of the rectifier bridge T2 is connected to a capacitor C1. This circuit is used to charge the capacitor C1 for magnetic stimulation output.

[0008] Furthermore, the high-voltage discharge circuit includes a trigger switch and a coil beat, which are connected in series. The trigger switch is connected to the DC high-voltage side, and a diode D1 is connected in parallel on the trigger switch. The diode D1 prevents reverse flow in the circuit. By controlling the opening of the trigger switch, the coil beat is discharged, thereby realizing the magnetic stimulation function of the coil beat.

[0009] Furthermore, the trigger switch is a silicon controlled rectifier (SCR) and also includes a trigger circuit. The trigger circuit includes a switching transistor Q5. Terminal 3 of the switching transistor Q5 is connected to the SCR through a current-limiting resistor R3. Terminal 2 of the switching transistor Q5 is connected to diode D2 and one end of transformer T3, respectively. The other end of transformer T3 is connected to terminal J1 through resistor R5.

[0010] Furthermore, the gate of MOSFET Q1 is connected to PWM1 through resistor R6, the gate of MOSFET Q4 is connected to PWM1 through resistor R7, the gate of MOSFET Q2 is connected to PWM2 through resistor R8, and the gate of MOSFET Q3 is connected to PWM2 through resistor R9.

[0011] Compared with the prior art, the beneficial effects of this utility model are:

[0012] 1. Through the inverter boost circuit, high voltage generation circuit, trigger circuit and other circuits, there is no need to turn off the PID regulator, and the magnetic stimulation output can be directly output, which greatly shortens the enable time of the regulator switch and increases the stimulation frequency.

[0013] 2. While ensuring magnetic field strength, it can have stable magnetic field output control and can output magnetic stimulation frequency of 0-200Hz, which plays a leading role in the research of pulse magnetic field stimulators. Attached Figure Description

[0014] Figure 1 This is a circuit diagram of the inverter boost circuit of this utility model;

[0015] Figure 2This is a circuit diagram of the high-voltage generating circuit of this utility model;

[0016] Figure 3 This is a circuit diagram of the high-voltage rectifier circuit of this utility model;

[0017] Figure 4 This is a circuit diagram of the high-voltage discharge circuit of this utility model;

[0018] Figure 5 This is a circuit diagram of the trigger circuit of this utility model;

[0019] Figure 6 This is a schematic diagram of the pulse control of this utility model. Detailed Implementation

[0020] The present invention will be further described below with reference to the accompanying drawings.

[0021] like Figure 1 – Figure 5 As shown in Example 1, a high-frequency output voltage control circuit for a pulsed magnetic field stimulator includes a high-voltage generating circuit and a high-voltage rectifier circuit. The high-voltage generating circuit and the high-voltage rectifier circuit are connected through an inverter boost circuit. The inverter boost circuit includes a transformer L1. The low-voltage side of the transformer L1 is connected to the drain (D) of MOSFET Q1, the drain (D) of MOSFET Q2, the source (S) of MOSFET Q3, and the source (S) of MOSFET Q4. The gate (G) of MOSFET Q1 and the gate (G) of MOSFET Q4 are both connected to PWM1, and the gate (G) of MOSFET Q2 and the gate (G) of MOSFET Q3 are both connected to PWM2. PWM1 and PWM2 are two PWM waves generated diagonally with a phase difference of 180°. The source (S) of MOSFET Q1 and the source (S) of MOSFET Q2 are connected to the high-voltage generating circuit. The high-voltage side of transformer L1 is connected to a high-voltage rectifier circuit, and capacitor C1 of the high-voltage rectifier circuit is connected to a high-voltage discharge circuit. Two PWM waves with a 180° phase difference are generated diagonally through the MOSFET drive circuit. The generated PWM is applied to MOSFETs Q1, Q4 and Q2, Q3 respectively, controlling the alternating conduction and cutoff of the two sets of MOSFETs. When MOSFETs Q1 and Q4 are on, MOSFETs Q2 and Q3 are off, and when MOSFETs Q2 and Q3 are on, MOSFETs Q1 and Q4 are off. This cycle repeats, forming an alternating current in the primary winding of the transformer, thus generating alternating current. This converts DC 300V to AC 300V, which is then stepped up by the step-up transformer L1.

[0022] Example 2: A high-frequency output voltage control circuit for a pulsed magnetic field stimulator. The high-voltage generating circuit includes a rectifier bridge T1. A filter capacitor C29, a resistor R1, and a filter capacitor C30 are connected in parallel to the output terminals of rectifier bridge T1. The source terminals of MOSFETs Q1 and Q2 are connected to the filter capacitor C30. AC mains power is rectified by rectifier bridge T1 and the filters C29 and C30, converting 220V AC to 300V DC. The high-voltage rectifier circuit includes a rectifier bridge T2. The input terminal of rectifier bridge T2 is connected to the high-voltage side of transformer L1, and the output terminal of rectifier bridge T2 is connected to capacitor C1, rectifying the inverter's high voltage to high-voltage DC. The high-voltage AC after high voltage boosting is converted to high-voltage DC by rectifier bridge T2 to charge capacitor C1, which is used for magnetic stimulation output. The high-voltage discharge circuit includes a trigger switch and a coil beater connected in series. The circuit is connected to the DC high-voltage side. A diode D1 is connected in parallel with the trigger switch to prevent reverse current in the circuit. By controlling the opening of the trigger switch, the coil is discharged, realizing the magnetic stimulation function of the coil. The trigger switch is a silicon controlled rectifier (SCR) and also includes a trigger circuit. The trigger circuit includes a switching transistor Q5. Terminal 3 of the switching transistor Q5 is connected to the SCR through a current-limiting resistor R3. Terminal 2 of the switching transistor Q5 is connected to diode D2 and one end of transformer T3, respectively. The other end of transformer T3 is connected to terminal J1 through resistor R5. The gate of MOSFET Q1 is connected to PWM1 through resistor R6. The gate of MOSFET Q4 is connected to PWM1 through resistor R7. The gate of MOSFET Q2 is connected to PWM2 through resistor R8. The gate of MOSFET Q3 is connected to PWM2 through resistor R9. The trigger circuit is used to control the magnetic stimulation output frequency and the modulation of various modes (standard mode, burst mode, single-beat pair, double-beat pair). The desired magnetic stimulation output frequency is written to the microcontroller, which then outputs a pulse stimulation switch signal at the corresponding frequency. This signal is current-limited by resistor R3 and then sent to switch Q5 to control the conduction and turn-off of switch Q5. The continuous turn-off of switch Q5 generates a pulse signal, which is used to control the on / off state of thyristor by the voltage reduction of transformer T3, thereby controlling the discharge of control capacitor C1 and thus controlling the magnetic stimulation output. The rest is the same as in Example 1.

[0023] Treatment modes (various modes are achieved by controlling the frequency of pulse stimulation and the interval time, such as...) Figure 6 As shown):

[0024] Standard mode: adjustable frequency, adjustable number of repetitions, adjustable interval time, and adjustable number of repetitions;

[0025] Burst mode: adjustable frequency within clusters, adjustable number of clusters, adjustable frequency between clusters, adjustable number of clusters between clusters, adjustable interval time, and adjustable number of repetitions;

[0026] Queue mode: A combination of standard mode and burst mode;

[0027] Paired mode: Two treatment frequencies alternate.

[0028] After the program starts, first configure the device's working mode (standard mode, burst mode, modulation mode, single / double beat paired mode), and then configure the working parameters (magnetic field strength, inner frequency, number of inner clusters, inter-cluster frequency, number of inter-clusters, interval time, number of repetitions) in the corresponding mode. Click to start treatment. After the boost module boosts to the target voltage, it performs PID voltage regulation. When the timer expires, it is immediately triggered to output the magnetic field. Then, it performs voltage regulation again and waits for the output until the treatment time ends (i.e., the timer ends). Finally, stop the treatment.

[0029] Similar products on the market require stopping voltage regulation before stimulation, and the voltage regulator switch takes a certain amount of time to turn from off to on, thus limiting the output frequency. This invention eliminates the need to turn off the PID voltage regulator and directly outputs magnetic stimulation, greatly shortening the enable time of the voltage regulator switch and increasing the stimulation frequency.

Claims

1. A high-frequency output voltage control circuit for a pulsed magnetic field stimulator, comprising a high-voltage generating circuit and a high-voltage rectifier circuit, characterized in that: The high-voltage generating circuit and the high-voltage rectifier circuit are connected through an inverter boost circuit. The inverter boost circuit includes a transformer L1. The low-voltage side of the transformer L1 is connected to the drain (D) of MOSFET Q1, the drain (D) of MOSFET Q2, the source (S) of MOSFET Q3, and the source (S) of MOSFET Q4. The gate (G) of MOSFET Q1 and the gate (G) of MOSFET Q4 are both connected to PWM1, and the gate (G) of MOSFET Q2 and the gate (G) of MOSFET Q3 are both connected to PWM2. PWM1 and PWM2 are two PWM waves generated diagonally with a phase difference of 180°. The source (S) of MOSFET Q1 and the source (S) of MOSFET Q2 are connected to the high-voltage generating circuit. The high-voltage side of the transformer L1 is connected to the high-voltage rectifier circuit. The capacitor C1 of the high-voltage rectifier circuit is connected to the high-voltage discharge circuit.

2. The high-frequency output voltage control circuit of the pulse magnetic field stimulator according to claim 1, characterized in that: The high-voltage generating circuit includes a rectifier bridge T1. The output terminals of the rectifier bridge T1 are connected in parallel with a filter capacitor C29, a resistor R1, and a filter capacitor C30. The source terminals of MOSFET Q1 and MOSFET Q2 are connected to the filter capacitor C30.

3. The high-frequency output voltage control circuit of the pulse magnetic field stimulator according to claim 1, characterized in that: The high-voltage rectifier circuit includes a rectifier bridge T2, the input terminal of which is connected to the high-voltage side of the transformer L1, and the output terminal of the rectifier bridge T2 is connected to a capacitor C1.

4. The high-frequency output voltage control circuit of the pulse magnetic field stimulator according to claim 3, characterized in that: The high-voltage discharge circuit includes a trigger switch and a coil beater connected in series. The trigger switch is connected to the DC high-voltage side, and a diode D1 is connected in parallel on the trigger switch to prevent reverse flow in the circuit.

5. The high-frequency output voltage control circuit of the pulse magnetic field stimulator according to claim 4, characterized in that: The trigger switch is a silicon controlled rectifier (SCR) and also includes a trigger circuit. The trigger circuit includes a switching transistor Q5. Terminal 3 of the switching transistor Q5 is connected to the SCR through a current-limiting resistor R3. Terminal 2 of the switching transistor Q5 is connected to diode D2 and one end of transformer T3, respectively. The other end of transformer T3 is connected to terminal J1 through resistor R5.

6. The high-frequency output voltage control circuit of the pulse magnetic field stimulator according to claim 1, characterized in that: The gate of MOSFET Q1 is connected to PWM1 through resistor R6; the gate of MOSFET Q4 is connected to PWM1 through resistor R7; the gate of MOSFET Q2 is connected to PWM2 through resistor R8; and the gate of MOSFET Q3 is connected to PWM2 through resistor R9.

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