CN110797877B

CN110797877B - High-voltage generator bus voltage control method and high-voltage generator

Info

Publication number: CN110797877B
Application number: CN201911066408.8A
Authority: CN
Inventors: 胡天慧; 孙平
Original assignee: NINGBO EST TECHNOLOGY CO LTD
Current assignee: NINGBO EST TECHNOLOGY CO LTD
Priority date: 2019-11-04
Filing date: 2019-11-04
Publication date: 2022-06-21
Anticipated expiration: 2039-11-04
Also published as: CN110797877A

Abstract

The invention discloses a bus voltage control method of a high-voltage generator and the high-voltage generator, wherein the bus voltage limit value is adaptively selected according to the set OUTPUT voltage after the OUTPUT voltage is set by setting a standard bus voltage limit value, a bus voltage comparison value DC _ LOW and an OUTPUT voltage comparison value KV _ OUTPUT _ COMP, and the bus voltage is controlled and real-time monitoring of a charging circuit and a discharging circuit is realized by monitoring the bus voltage in the working process of the high-voltage generator; the advantage is on the basis of guaranteeing tank circuit safe handling, can adopt withstand voltage lower tank circuit, reduce tank circuit medium storage capacitor's use quantity, thereby reduce high voltage generator's volume, reduce high voltage generator's cost, monitor whether inside charging circuit of high voltage generator and discharge circuit are in normal operating condition through the monitoring to busbar voltage, improve high voltage generator's security and reliability, and when the output voltage who sets for is lower, also can avoid output voltage to float high problem.

Description

High-voltage generator bus voltage control method and high-voltage generator

Technical Field

The invention relates to a bus voltage control technology of a high-voltage generator, in particular to a bus voltage control method of the high-voltage generator and the high-voltage generator.

Background

A schematic circuit diagram of an existing high voltage generator is shown in fig. 1, in the high voltage generator, an electronic switch, a current limiting module, and a rectifying circuit form a charging circuit, and a working process of the high voltage generator is as follows: when the power grid voltage is connected, the input booster circuit boosts the connected power grid voltage, a worker starts the main control module to enable the main control module to enter a working state, the main control module controls the electronic switch to be conducted at the moment, the power grid voltage sequentially passes through a charging circuit formed by the input booster circuit, the electronic switch, the current limiting module and the rectifying circuit and then charges the energy storage circuit, and the energy storage circuit outputs bus voltage DC at the moment. When the output voltage of the high-voltage generator needs to be changed, a worker changes the set output voltage of the high-voltage generator in the main control module, the main control module controls the inverter circuit to invert the bus voltage DC into alternating voltage, the alternating voltage is boosted by the output booster circuit to obtain the output voltage to be output, the feedback circuit collects the real-time value of the output voltage of the output booster circuit and feeds the real-time value back to the main control module, the main control module adjusts the on-off control of the inside of the inverter circuit according to the real-time value of the output voltage, the accuracy of the output voltage of the high-voltage generator is higher, the discharging circuit monitors whether the input booster circuit is connected with the power grid voltage or not in real time, when the input booster circuit is connected with the power grid voltage, the discharging circuit does not work, and the discharging circuit discharges electricity for the energy storage circuit.

In the above-mentioned high voltage generator, the magnitude of the bus voltage DC is directly dependent on the incoming grid voltage, thereby leading to the following problems: firstly, when a high-voltage generator is designed currently, an energy storage circuit is realized by adopting a plurality of energy storage capacitor groups, so that the normal use of the energy storage circuit is ensured in order to avoid the damage or explosion caused by overhigh temperature of the energy storage capacitors in the energy storage circuit, and the bus voltage DC must be lower than the withstand voltage value of the energy storage circuit; in order to ensure that the withstand voltage value of the energy storage circuit is higher than the actual bus voltage, the withstand voltage of the energy storage circuit is higher than the maximum value of the bus voltage fluctuation interval when the energy storage circuit is designed currently, and the energy storage E (1/2C V) of the energy storage circuit is stored according to a capacitance energy formula²Wherein, is a multiplication symbol, and C is the total capacitance of all the energy storage capacitors in the energy storage circuit; v is the output voltage of the energy storage circuit, namely the bus voltage, in order to ensure safety, for the capacitors with the same withstand voltage value, the bus voltage can only be relatively smaller, and for the same energy storage requirement, the smaller V is, the larger C is, so that the number of the energy storage capacitors in the energy storage circuit is increased, and finally the volume and the cost of the high-voltage generator are increased. In the working process of the high-voltage generator, the bus voltage is in an out-of-control state, and the problems of whether the bus voltage exceeds the limit, whether the charging circuit works normally, whether the discharging circuit works normally and the like cannot be known, namely, whether the high-voltage generator is in a normal working state cannot be determined, and the safety and the reliability are not high. Setting the output voltage of the high-voltage generator through the main control module, and when different output voltages are set, as long as the power grid voltage is unchanged, the bus voltage is the same, so that when the set output voltage is higher, the energy consumed in the high-voltage generator is low, and when the set output voltage is lower, the energy consumed in the high-voltage generator is lowThe consumed energy is high, and once excessive energy cannot be completely consumed in the high-voltage generator, the internal steady state of the high-voltage generator cannot be maintained, and at the moment, the final output voltage is floated, and the output is in a problem.

Disclosure of Invention

One of the technical problems to be solved by the invention is to provide a bus voltage control method of a high-voltage generator, which controls the bus voltage, can adopt an energy storage circuit with lower withstand voltage on the basis of ensuring the safe use of the energy storage circuit, and reduces the use number of energy storage capacitors in the energy storage circuit, thereby reducing the volume of the high-voltage generator and reducing the cost of the high-voltage generator.

The technical scheme adopted by the invention for solving one of the technical problems is as follows: a bus voltage control method of a high-voltage generator comprises the following steps:

(1) setting control parameters in a main control module of the HIGH-voltage generator, wherein the control parameters comprise a first bus voltage limit value DC _ HIGH1, a second bus voltage limit value DC _ HIGH2, a standard bus voltage limit value DC _ HIGH, a bus voltage comparison value DC _ LOW and an OUTPUT voltage comparison value KV _ OUTPUT _ COMP, and recording the voltage boosting ratio of an input voltage boosting circuit of the HIGH-voltage generator as 1: n, the range of the first bus voltage limit value DC _ HIGH1 is 311N-342N volts, the range of the bus voltage comparison value DC _ LOW is ((DC _ HIGH-10) V-DC _ HIGH-5) V, the range of the second bus voltage limit value DC _ HIGH2 is smaller than the first bus voltage limit value DC _ HIGH1, the value of the OUTPUT voltage comparison value KV _ OUTPUT _ COMP is within the rated OUTPUT voltage range of the HIGH-voltage generator, and the values of the second bus voltage limit value DC _ HIGH2 and the OUTPUT voltage comparison value OUTPUT _ COMP simultaneously meet the following conditions that when the main control module of the HIGH-voltage generator sets the OUTPUT voltage KV as the rated OUTPUT voltage minimum value, the OUTPUT current as the rated OUTPUT current minimum value and the OUTPUT time as the rated OUTPUT time shortest time, the deviation between the actual OUTPUT voltage and the set OUTPUT voltage of the HIGH-voltage generator is within 5%, when the main control module of the high-voltage generator sets that the OUTPUT voltage is equal to the OUTPUT voltage comparison value KV _ OUTPUT _ COMP, the OUTPUT current is the maximum value of the rated OUTPUT current, and the OUTPUT time is the longest time of the rated OUTPUT time, the deviation between the actual OUTPUT voltage of the high-voltage generator and the set OUTPUT voltage is within 5%;

(2) the high-voltage generator has two working modes: a charging mode and a discharging mode; when the input booster circuit of the high-voltage generator is connected to the voltage of a power grid, an operator sets output voltage in the main control module and starts the main control module, and the main control module automatically sets a standard bus voltage limit value according to the set output voltage: if the set OUTPUT voltage is greater than an OUTPUT voltage comparison value KV _ OUTPUT _ COMP, making DC _ HIGH equal to DC _ HIGH1, wherein the value range of a bus voltage comparison value DC _ LOW is (DC _ HIGH1-10) - (DC _ HIGH1-5) volts, if the set OUTPUT voltage is less than or equal to the OUTPUT voltage comparison value KV _ OUTPUT _ COMP, making DC _ HIGH equal to DC _ HIGH2, the value range of the bus voltage comparison value DC _ LOW is (DC _ HIGH2-10) - (DC _ HIGH2-5) volts, and after the standard bus voltage limit value is set, the HIGH-voltage generator enters a charging mode;

(3) when the high-voltage generator is in a charging mode, the main control module controls the charging circuit to be conducted, the charging circuit enters a charging stage, the discharging circuit is in a closed state at the moment, the charging circuit charges the energy storage circuit in the charging stage of the charging circuit, the feedback circuit collects a real-time value of the output voltage of the output boosting circuit and feeds the real-time value back to the main control module, the main control module controls the internal on-off of the inverter circuit according to the real-time value of the output voltage of the output boosting circuit, and the main control module starts timing from zero and obtains a real-time value of a bus voltage DC output by the energy storage circuit and conducts timing on the bus voltage DCThe real-time value of the DC is compared with the standard bus voltage limit value in real time, and R is reached when the timing is reached_H×C_{General assembly}Then, the real-time value of the current bus voltage DC is further compared with 0.63 × 311N volts: if the real-time value of the bus voltage DC is less than or equal to the standard bus voltage limit value, the high-voltage generator keeps a charging mode, if the real-time value of the bus voltage DC is greater than the standard bus voltage limit value, the main control module controls the charging circuit to be disconnected, the charging stage of the charging circuit is ended, the high-voltage generator is switched from the charging mode to a discharging mode, and if the timing of the main control module reaches R in the process that the high-voltage generator keeps the charging mode, the main control module keeps the charging mode_H×C_{General assembly}Wherein R is_HRepresenting the total resistance of the charging circuit, C_{General assembly}The total capacitance value of the energy storage circuit is represented, and the real-time value of the current bus voltage DC is less than 0.63 × 311N volts, the charging circuit is damaged, the main control module controls the charging circuit to be disconnected, the charging circuit to be closed, controls the inverter circuit to stop working, the output booster circuit has no output voltage output, the high-voltage generator stops working, otherwise, the high-voltage generator continues to keep the charging mode; when the high voltage generator is in a discharging mode, the main control module controls the discharging circuit to be started, the discharging circuit enters a discharging stage, the discharging circuit discharges the energy storage circuit in the discharging stage of the discharging circuit, the main control module obtains a real-time value of bus voltage DC output by the energy storage circuit, compares the real-time value of the bus voltage DC with a bus voltage comparison value DC _ LOW, and compares the real-time value of the current bus voltage with a real-time value of the previous bus voltage: if the real-time value of the bus voltage DC is greater than or equal to the bus voltage comparison value DC _ LOW, the high-voltage generator keeps a discharging mode, if the real-time value of the bus voltage DC is less than or equal to the bus voltage comparison value DC _ LOW, the main control module closes the discharging circuit at the moment and controls the charging circuit to be conducted, the high-voltage generator is switched from the discharging mode to the charging mode, and in the process that the high-voltage generator keeps the discharging mode, if the real-time value of the current bus voltage is relative to the previous bus voltage, the real-time value of the current bus voltage is relative to the previous bus voltageIf the real-time value of the voltage is not reduced, the discharge circuit is damaged, the main control module controls the charging circuit to be disconnected, the charging circuit to be closed, the inverter circuit to stop working and the high-voltage generator to stop working at the moment, and otherwise, the high-voltage generator continues to keep the discharge mode.

Compared with the prior art, the control method has the advantages that the standard bus voltage limit value is adaptively selected according to the set OUTPUT voltage after the OUTPUT voltage is set through setting the standard bus voltage limit value, the bus voltage comparison value DC _ LOW and the OUTPUT voltage comparison value KV _ OUTPUT _ COMP, and in the working process of the high-voltage generator, the bus voltage is controlled through monitoring the bus voltage and real-time monitoring of the charging circuit and the discharging circuit is realized, so that on the basis of ensuring safe use of the energy storage circuit, the energy storage circuit with lower withstand voltage can be adopted, the use number of the energy storage capacitors in the energy storage circuit is reduced, the volume of the high-voltage generator is reduced, the cost of the high-voltage generator is reduced, whether the charging circuit and the discharging circuit in the high-voltage generator are in normal working state or not is monitored through monitoring the bus voltage, and the safety and the reliability of the high-voltage generator are improved, and when the set output voltage is lower, the problem of output voltage floating can be avoided due to the adaptive selection of the standard bus voltage limit value.

The second technical problem to be solved by the present invention is to provide a high voltage generator, which can adopt an energy storage circuit with lower withstand voltage by controlling the bus voltage on the basis of ensuring the safe use of the energy storage circuit, and reduce the number of energy storage capacitors in the energy storage circuit, thereby reducing the volume of the high voltage generator and the cost of the high voltage generator, and meanwhile, the monitoring of whether the working states of an internal discharging circuit and a charging circuit are normal or not is realized by monitoring the bus voltage, so that the safety and reliability are higher, and when the set output voltage is lower, the problem of floating of the output voltage can be avoided.

The technical scheme adopted by the invention for solving the technical problems is as follows: a high-voltage generator comprises a main control module, an input booster circuit, a charging circuit, an energy storage circuit and an inverter circuitThe sampling circuit, the discharging circuit and the feedback circuit are respectively connected with the main control module, the charging circuit is connected with the energy storage circuit, the sampling circuit is connected with the energy storage circuit, the discharging circuit is connected with the feedback circuit, the sampling circuit is connected with the energy storage circuit, the energy storage circuit is connected with the inverter circuit, the inverter circuit is connected with the output boosting circuit, and the output boosting circuit is connected with the feedback circuit; the charging circuit is used for charging the energy storage circuit, the discharging circuit is used for discharging the energy storage circuit, the feedback circuit is used for collecting a real-time value of output voltage of the output booster circuit and feeding the real-time value back to the main control module, the sampling circuit is used for collecting a real-time value of bus voltage DC output by the energy storage circuit and feeding the real-time value back to the main control module, the inverter circuit is used for inverting and converting the bus voltage output by the energy storage circuit into alternating voltage, the output booster circuit is used for boosting the alternating voltage output by the inverter circuit to obtain required output high-voltage output, and the output booster circuit is used for controlling the work of the charging circuit, the discharging circuit and the main control circuit; the main control module is internally provided with control parameters, the control parameters comprise a first bus voltage limit value DC _ HIGH1, a second bus voltage limit value DC _ HIGH2, a standard bus voltage limit value DC _ HIGH, a bus voltage comparison value DC _ LOW and an OUTPUT voltage comparison value KV _ OUTPUT _ COMP, and the voltage boost ratio of an input voltage boost circuit of the HIGH voltage generator is recorded as 1: n, the value range of the first bus voltage limit value DC _ HIGH1 is 311N-342N volts, the value range of the bus voltage comparison value DC _ LOW is ((DC _ HIGH-10) to (DC _ HIGH-5) volts, the value of the second bus voltage limit value DC _ HIGH2 is smaller than that of the first bus voltage limit value DC _ HIGH1, the value of the OUTPUT voltage comparison value KV _ OUTPUT _ COMP is located in the rated OUTPUT voltage range of the HIGH-voltage generator, and the value of the second bus voltage limit value DC _ HIGH2 and the value of the OUTPUT voltage comparison value KV _ OUTPUT _ COMP simultaneously meet the requirement that KV _ OUTPUT _ COMP is acquiredThe following conditions were used: when the main control module of the high-voltage generator sets that the OUTPUT voltage is the minimum value of the rated OUTPUT voltage, the OUTPUT current is the minimum value of the rated OUTPUT current and the OUTPUT time is the shortest time of the rated OUTPUT time, the deviation between the actual OUTPUT voltage of the high-voltage generator and the set OUTPUT voltage is within 5 percent, and when the main control module of the high-voltage generator sets that the OUTPUT voltage is equal to the comparison value KV _ OUTPUT _ COMP of the OUTPUT voltage, the OUTPUT current is the maximum value of the rated OUTPUT current and the OUTPUT time is the longest time of the rated OUTPUT time, the deviation between the actual OUTPUT voltage of the high-voltage generator and the set OUTPUT voltage is within 5 percent; the high-voltage generator has two working modes: a charging mode and a discharging mode; when the input booster circuit of the high-voltage generator is connected to the voltage of a power grid, an operator sets output voltage in the main control module and starts the main control module, and the main control module automatically sets a standard bus voltage limit value according to the set output voltage: if the set OUTPUT voltage is greater than an OUTPUT voltage comparison value KV _ OUTPUT _ COMP, making DC _ HIGH equal to DC _ HIGH1, wherein the value range of a bus voltage comparison value DC _ LOW is (DC _ HIGH1-10) - (DC _ HIGH1-5) volts, if the set OUTPUT voltage is less than or equal to the OUTPUT voltage comparison value KV _ OUTPUT _ COMP, making DC _ HIGH equal to DC _ HIGH2, wherein the value range of the bus voltage comparison value DC _ LOW is (DC _ HIGH2-10) - (DC _ HIGH2-5) volts, and after the standard bus voltage limit value is set, the HIGH-voltage generator enters a charging mode; when the high-voltage generator is in a charging mode, the main control module controls the charging circuit to be conducted, the charging circuit enters a charging stage, the discharging circuit is in a closed state at the moment, the charging circuit charges the energy storage circuit in the charging stage of the charging circuit, the feedback circuit collects a real-time value of the output voltage of the output booster circuit and feeds the real-time value back to the main control module, the main control module controls the internal on-off of the inverter circuit according to the real-time value of the output voltage of the output booster circuit, and the main control module starts timing from zero and obtains the internal on-off of the inverter circuit through the sampling circuitThe real-time value of the bus voltage DC output by the energy storage circuit is compared with the standard bus voltage limit value in real time, and R is reached when the timing is reached_H×C_{General assembly}Then, the real-time value of the current bus voltage DC is further compared with 0.63 × 311N volts: if the real-time value of the bus voltage DC is less than or equal to the standard bus voltage limit value, the high-voltage generator keeps a charging mode, if the real-time value of the bus voltage DC is greater than the standard bus voltage limit value, the main control module controls the charging circuit to be disconnected, the charging stage of the charging circuit is ended, the high-voltage generator is switched from the charging mode to a discharging mode, and if the timing of the main control module reaches R in the process that the high-voltage generator keeps the charging mode, the main control module keeps the charging mode_H×C_{General assembly}Wherein R is_HRepresenting the total resistance of the charging circuit, C_{General assembly}The total capacitance value of the energy storage circuit is represented, and the real-time value of the current bus voltage DC is less than 0.63 × 311N volts, the charging circuit is damaged, the main control module controls the charging circuit to be disconnected, the charging circuit to be closed, controls the inverter circuit to stop working, the output booster circuit has no output voltage output, the high-voltage generator stops working, otherwise, the high-voltage generator continues to keep the charging mode; when the high voltage generator is in a discharging mode, the main control module controls the discharging circuit to be started, the discharging circuit enters a discharging stage, the discharging circuit discharges the energy storage circuit in the discharging stage of the discharging circuit, the main control module obtains a real-time value of the bus voltage DC output by the energy storage circuit through the sampling circuit, compares the real-time value of the bus voltage DC with a bus voltage comparison value DC _ LOW, and compares the real-time value of the current bus voltage with a real-time value of the previous bus voltage: if the real-time value of the bus voltage DC is greater than or equal to the bus voltage comparison value DC _ LOW, the high-voltage generator keeps a discharging mode, if the real-time value of the bus voltage DC is less than or equal to the bus voltage comparison value DC _ LOW, the main control module closes the discharging circuit at the moment and controls the charging circuit to be conducted, the high-voltage generator is switched from the discharging mode to the charging mode, and the charging mode is switched to the high-voltage generator at the high voltageIn the process that the voltage generator keeps the discharging mode, if the real-time value of the current bus voltage is not reduced relative to the real-time value of the previous bus voltage, the discharging circuit is damaged, at the moment, the main control module controls the charging circuit to be disconnected, the charging circuit to be closed, controls the inverter circuit to stop working, and controls the high-voltage generator to stop working, otherwise, the high-voltage generator keeps the discharging mode continuously.

The energy storage circuit comprises a first energy storage capacitor group and a second energy storage capacitor group, the first energy storage capacitor group and the second energy storage capacitor group are respectively provided with a positive pole and a negative pole, the negative pole of the first energy storage capacitor group is connected with the positive pole of the second energy storage capacitor group, bus voltage DC is generated between the positive pole of the first energy storage capacitor group and the negative pole of the second energy storage capacitor group, the input booster circuit comprises a first transformer, the first transformer is provided with a primary coil and a secondary coil, the charging circuit comprises an electronic switch, a first resistor, a first diode and a second diode, the first diode and the second diode are rectifier diodes, the sampling circuit comprises a second resistor, a third resistor and a fourth resistor, the inverter circuit comprises four controllable switching devices, each controllable switch device is respectively provided with a control end, a first connecting end and a second connecting end, the controllable switch devices control the connection or disconnection of the first connecting end and the second connecting end through signals accessed by the control ends of the controllable switch devices, the four controllable switch devices are respectively called a first controllable switch device, a second controllable switch device, a third controllable switch device and a fourth controllable switch device, the output boosting circuit comprises a first inductor, a first capacitor and a second transformer, the second transformer is provided with a primary coil and a secondary coil, two ends of the primary coil of the first transformer are used for mains voltage, the electronic switch is provided with a first input end, a second input end, a first output end, a second output end and a control end, the first input end of the electronic switch is connected with one end of the secondary coil of the first transformer, the second input end of the electronic switch is connected with the other end of the secondary coil of the first transformer, the first output end of the electronic switch is connected with one end of the first resistor, the second output end of the electronic switch is connected with the connecting ends of the first energy-storage capacitor group and the second energy-storage capacitor group, the other end of the first resistor is respectively connected with the anode of the first diode and the cathode of the second diode, the cathode of the first diode is connected with the anode of the first energy-storage capacitor group, the anode of the second diode is connected with the cathode of the second energy-storage capacitor group, one end of the second resistor is connected with the anode of the first energy-storage capacitor group, the other end of the second resistor is connected with one end of the third resistor, and the other end of the third resistor is connected with one end of the fourth resistor, the other end of the fourth resistor is connected with the negative electrode of the second energy storage capacitor group, the connecting end of the third resistor and the fourth resistor is connected with the main control module, the discharge circuit is provided with a positive electrode, a negative electrode and a control end, the control end of the discharge circuit is connected with the main control module, the positive electrode of the discharge circuit is connected with the positive electrode of the first energy storage capacitor group, the negative electrode of the discharge circuit is connected with the negative electrode of the second energy storage capacitor group, the control end of the first controllable switch device, the control end of the second controllable switch device, the control end of the third controllable switch device and the control end of the fourth controllable switch device are respectively connected with the main control module, the second connecting end of the first controllable switch device and the second connecting end of the second controllable switch device are both connected with the positive electrode of the first energy storage capacitor group, the first connection end of the third controllable switching device and the first connection end of the fourth controllable switching device are both connected with the negative electrode of the second energy storage capacitor bank, the first connection end of the first controllable switching device, the second connection end of the third controllable switching device and one end of the first inductor are connected, the other end of the first inductor is connected with one end of the first capacitor, the other end of the first capacitor is connected with one end of the primary coil of the second transformer, the first connection end of the second controllable switching device, the second connection end of the third controllable switching device and the other end of the primary coil of the second transformer are connected, output voltage is output between two ends of the secondary coil of the second transformer, and the feedback circuit collects output voltage output between two ends of the secondary coil of the second transformer and feeds back the output voltage to the main control module, the first controllable switch device and the second controllable switch device are used as a first group of controllable switch devices, the second controllable switch device and the third controllable switch device are used as a second group of controllable switch devices, and the main control module controls the on-off of the interior of the inverter circuit by controlling the first group of controllable switch devices and the second group of controllable switch devices to be conducted alternately.

The four controllable switch devices are respectively realized by MOS tubes or IGBT tubes, when the four controllable switch devices are respectively realized by MOS tubes, the grid electrode of the MOS tube is used as the control end of the controllable switch device, the source electrode and the drain electrode of the MOS tube are used as the first connecting end and the second connecting end of the controllable switch device, when the four controllable switch devices are respectively realized by IGBT tubes, the grid electrode of the IGBT tube is used as the control end of the controllable switch device, and the source electrode and the drain electrode of the IGBT tube are used as the first connecting end and the second connecting end of the controllable switch device.

Compared with the prior art, the high-voltage generator has the advantages that the high-voltage generator adaptively selects the standard bus voltage limit value according to the set OUTPUT voltage after setting the OUTPUT voltage by setting the standard bus voltage limit value, the bus voltage comparison value DC _ LOW and the OUTPUT voltage comparison value KV _ OUTPUT _ COMP, and samples the bus voltage in real time through the set sampling circuit and feeds the sampled bus voltage back to the main control module in the working process of the high-voltage generator, the main control module controls the bus voltage according to the sampled data, and monitors the bus voltage to realize the real-time monitoring of the charging circuit and the discharging circuit, so that the energy storage circuit with lower withstand voltage can be adopted on the basis of ensuring the safe use of the energy storage circuit, the use number of energy storage capacitors in the energy storage circuit is reduced, the volume of the high-voltage generator is reduced, and the cost of the high-voltage generator is reduced, meanwhile, whether the working states of the internal discharging circuit and the charging circuit are normal or not is monitored by monitoring the bus voltage, the safety and the reliability are high, and when the set output voltage is low, the problem of output voltage floating can be avoided due to the fact that the standard bus voltage limit value is selected adaptively.

Drawings

FIG. 1 is a schematic circuit diagram of a conventional high voltage generator;

FIG. 2 is a schematic circuit diagram of the high voltage generator of the present invention;

fig. 3 is a circuit configuration diagram of the high voltage generator of the present invention.

Detailed Description

The invention is described in further detail below with reference to the accompanying examples.

The invention discloses a bus voltage control method of a high-voltage generator, which is further described in detail by combining the embodiment of the attached drawings.

Example (b): a bus voltage control method of a high-voltage generator comprises the following steps:

(1) setting control parameters in a main control module of the HIGH-voltage generator, wherein the control parameters comprise a first bus voltage limit value DC _ HIGH1, a second bus voltage limit value DC _ HIGH2, a standard bus voltage limit value DC _ HIGH, a bus voltage comparison value DC _ LOW and an OUTPUT voltage comparison value KV _ OUTPUT _ COMP, and recording the voltage boosting ratio of an input voltage boosting circuit of the HIGH-voltage generator as 1: n, the value range of the first bus voltage limiting value DC _ HIGH1 is 311N-342N volts, the value range of the bus voltage comparison value DC _ LOW is ((DC _ HIGH-10) to (DC _ HIGH-5) volts, the value of the second bus voltage limiting value DC _ HIGH2 is smaller than that of the first bus voltage limiting value DC _ HIGH1, the value of the OUTPUT voltage comparison value KV _ OUTPUT _ COMP is within the rated OUTPUT voltage range of the HIGH-voltage generator, and the value of the second bus voltage limiting value DC _ HIGH2 and the value of the OUTPUT voltage comparison value KV _ OUTPUT _ COMP simultaneously meet the following conditions that when a main control module of the HIGH-voltage generator sets the OUTPUT voltage as the rated OUTPUT voltage minimum value, the OUTPUT current as the rated OUTPUT current minimum value and the OUTPUT time as the rated OUTPUT time shortest time, the deviation between the actual OUTPUT voltage and the set OUTPUT voltage of the HIGH-voltage generator is within 5%, when the main control module of the high-voltage generator sets that the OUTPUT voltage is equal to the OUTPUT voltage comparison value KV _ OUTPUT _ COMP, the OUTPUT current is the maximum value of the rated OUTPUT current, and the OUTPUT time is the longest time of the rated OUTPUT time, the deviation between the actual OUTPUT voltage of the high-voltage generator and the set OUTPUT voltage is within 5%;

(2) the high voltage generator has two modes of operation: a charging mode and a discharging mode; when the input booster circuit of the high-voltage generator is connected to the voltage of the power grid, an operator sets output voltage in the main control module and starts the main control module, and the main control module automatically sets the standard bus voltage limit value according to the set output voltage: if the set OUTPUT voltage is greater than an OUTPUT voltage comparison value KV _ OUTPUT _ COMP, making DC _ HIGH equal to DC _ HIGH1, wherein the value range of a bus voltage comparison value DC _ LOW is (DC _ HIGH1-10) - (DC _ HIGH1-5) volt, if the set OUTPUT voltage is less than or equal to the OUTPUT voltage comparison value KV _ OUTPUT _ COMP, making DC _ HIGH equal to DC _ HIGH2, wherein the value range of the bus voltage comparison value DC _ LOW is ((DC _ HIGH2-10) - (DC _ HIGH2-5) volt, and after the standard bus voltage limit value is set, the HIGH-voltage generator enters a charging mode;

(3) when the high-voltage generator is in a charging mode, the main control module controls the charging circuit to be conducted, the charging circuit enters a charging stage, the discharging circuit is in a closed state at the moment, the charging circuit charges the energy storage circuit in the charging stage of the charging circuit, the feedback circuit collects a real-time value of the output voltage of the output boosting circuit and feeds the real-time value back to the main control module, the main control module controls the internal on-off of the inverter circuit according to the real-time value of the output voltage of the output boosting circuit, the main control module starts timing from zero and obtains a real-time value of the bus voltage DC output by the energy storage circuit, the real-time value of the bus voltage DC is compared with a standard bus voltage limit value in real time, and R is reached when timing_H×C_{General assembly}Further real-time of the present bus voltage DCThe value was compared to 0.63 × 311N volts: if the real-time value of the bus voltage DC is less than or equal to the standard bus voltage limit value, the high-voltage generator keeps a charging mode, if the real-time value of the bus voltage DC is greater than the standard bus voltage limit value, the main control module controls the charging circuit to be disconnected, the charging stage of the charging circuit is ended, the high-voltage generator is switched from the charging mode to a discharging mode, and in the process that the high-voltage generator keeps the charging mode, if the main control module reaches R in timing mode_H×C_{General assembly}Wherein R is_HRepresenting the total resistance of the charging circuit, C_{General assembly}The total capacitance value of the energy storage circuit is represented, and the real-time value of the current bus voltage DC is less than 0.63 × 311N volts, the charging circuit is damaged, the main control module controls the charging circuit to be disconnected, the charging circuit to be closed, controls the inverter circuit to stop working, the output booster circuit has no output voltage output, the high-voltage generator stops working, otherwise, the high-voltage generator continues to keep the charging mode; when the high-voltage generator is in a discharging mode, the main control module controls the discharging circuit to be started, the discharging circuit enters a discharging stage, the discharging circuit discharges the energy storage circuit in the discharging stage of the discharging circuit, the main control module obtains a real-time value of bus voltage DC output by the energy storage circuit, compares the real-time value of the bus voltage DC with a bus voltage comparison value DC _ LOW, and compares the real-time value of the current bus voltage with the real-time value of the previous bus voltage: if the real-time value of the bus voltage DC is greater than or equal to the bus voltage comparison value DC _ LOW, the high-voltage generator keeps a discharging mode, if the real-time value of the bus voltage DC is less than or equal to the bus voltage comparison value DC _ LOW, the main control module closes the discharging circuit at the moment, controls the charging circuit to be conducted, the high-voltage generator is switched from the discharging mode to the charging mode, in the process that the high-voltage generator keeps the discharging mode, if the real-time value of the current bus voltage is not reduced relative to the real-time value of the previous bus voltage, the discharging circuit is indicated to be damaged, at the moment, the main control module controls the charging circuit to be disconnected, the charging circuit is closed, controls the inverter circuit to stop working, the high-voltage generator stops working, and otherwise, the high-voltage generator continues to keep the discharging mode.

The invention also discloses a high voltage generator capable of realizing the bus voltage control method of the high voltage generator, and the high voltage generator of the invention is further described in detail by combining the embodiment of the attached drawings.

Example (b): as shown in fig. 2, a high voltage generator includes a main control module, an input boost circuit, a charging circuit, an energy storage circuit, an inverter circuit, a sampling circuit, a discharging circuit, an output boost circuit and a feedback circuit, wherein the main control module is respectively connected with the charging circuit, the inverter circuit, the sampling circuit, the discharging circuit and the feedback circuit, the charging circuit is connected with the energy storage circuit, the sampling circuit and the discharging circuit are respectively connected with the energy storage circuit, the energy storage circuit is connected with the inverter circuit, the inverter circuit is connected with the output boost circuit, and the output boost circuit is connected with the feedback circuit; the charging circuit is used for charging the energy storage circuit, the discharging circuit is used for discharging the energy storage circuit, the feedback circuit is used for acquiring a real-time value of output voltage of the output boosting circuit and feeding the real-time value back to the main control module, the sampling circuit is used for acquiring a real-time value of bus voltage DC output by the energy storage circuit and feeding the real-time value back to the main control module, the inverter circuit is used for inverting and converting the bus voltage output by the energy storage circuit into alternating voltage, the output boosting circuit is used for boosting the alternating voltage output by the inverter circuit to obtain required output high-voltage output, and the main control module is used for controlling the work of the charging circuit, the discharging circuit and the inverter circuit; the main control module is internally provided with control parameters, the control parameters comprise a first bus voltage limit value DC _ HIGH1, a second bus voltage limit value DC _ HIGH2, a standard bus voltage limit value DC _ HIGH, a bus voltage comparison value DC _ LOW and an OUTPUT voltage comparison value KV _ OUTPUT _ COMP, and the voltage boost ratio of an input voltage boost circuit of the HIGH voltage generator is recorded as 1: n, the value range of the first bus voltage limit value DC _ HIGH1 is 311N-342N volts, the value range of the bus voltage comparison value DC _ LOW is ((DC _ HIGH-10) to (DC _ HIGH-5) volts, the value of the second bus voltage limit value DC _ HIGH2 is smaller than that of the first bus voltage limit value DC _ HIGH1, the value of the OUTPUT voltage comparison value KV _ OUTPUT _ COMP is within the rated OUTPUT voltage range of the HIGH-voltage generator, and the value of the second bus voltage limit value DC _ HIGH2 and the value of the OUTPUT voltage comparison value KV _ OUTPUT _ COMP simultaneously meet the following conditions when the HIGH-voltage generator is HIGHWhen the main control module of the voltage generator sets the OUTPUT voltage to be the minimum value of the rated OUTPUT voltage, the OUTPUT current to be the minimum value of the rated OUTPUT current and the OUTPUT time to be the shortest time of the rated OUTPUT time, the deviation between the actual OUTPUT voltage of the high-voltage generator and the set OUTPUT voltage is within 5 percent, and when the main control module of the high-voltage generator sets the OUTPUT voltage to be equal to the comparison value KV _ OUTPUT _ COMP of the OUTPUT voltage, the OUTPUT current to be the maximum value of the rated OUTPUT current and the OUTPUT time to be the longest time of the rated OUTPUT time, the deviation between the actual OUTPUT voltage of the high-voltage generator and the set OUTPUT voltage is within 5 percent; the high voltage generator has two modes of operation: a charging mode and a discharging mode; when the input booster circuit of the high-voltage generator is connected to the voltage of the power grid, an operator sets output voltage in the main control module and starts the main control module, and the main control module automatically sets the standard bus voltage limit value according to the set output voltage: if the set OUTPUT voltage is greater than the OUTPUT voltage comparison value KV _ OUTPUT _ COMP, making DC _ HIGH equal to DC _ HIGH1, wherein the value range of the bus voltage comparison value DC _ LOW is (DC _ HIGH1-10) - (DC _ HIGH1-5) volt, if the set OUTPUT voltage is less than or equal to the OUTPUT voltage comparison value KV _ OUTPUT _ COMP, making DC _ HIGH equal to DC _ HIGH2, wherein the value range of the bus voltage comparison value DC _ LOW is (DC _ HIGH2-10) - (DC _ HIGH2-5) volt, and after the standard bus voltage limit value is set, the HIGH-voltage generator enters a charging mode; when the high-voltage generator is in a charging mode, the main control module controls the charging circuit to be conducted, the charging circuit enters a charging stage, the discharging circuit is in a closed state at the moment, the charging circuit charges the energy storage circuit in the charging stage of the charging circuit, the feedback circuit collects a real-time value of the output voltage of the output boosting circuit and feeds the real-time value back to the main control module, the main control module controls the internal on-off of the inverter circuit according to the real-time value of the output voltage of the output boosting circuit, the main control module starts timing from zero and obtains a real-time value of the bus voltage DC output by the energy storage circuit through the sampling circuit, the real-time value of the bus voltage DC is compared with a standard bus voltage limit value in real time, and R is reached when timing_H×C_{General assembly}Further comparing the real-time value of the current bus voltage DC with 0.63311N volts were compared: if the real-time value of the bus voltage DC is less than or equal to the standard bus voltage limit value, the high-voltage generator keeps a charging mode, if the real-time value of the bus voltage DC is greater than the standard bus voltage limit value, the main control module controls the charging circuit to be disconnected, the charging stage of the charging circuit is ended, the high-voltage generator is switched from the charging mode to a discharging mode, and in the process that the high-voltage generator keeps the charging mode, if the main control module reaches R in timing mode_H×C_{General assembly}Wherein R is_HRepresenting the total resistance of the charging circuit, C_{General assembly}The total capacitance value of the energy storage circuit is represented, and the real-time value of the current bus voltage DC is less than 0.63 × 311N volts, so that the charging circuit is damaged, the main control module controls the charging circuit to be disconnected, the charging circuit to be closed, the inverter circuit to stop working, the output booster circuit has no output voltage, the high-voltage generator stops working, and otherwise, the high-voltage generator continues to keep in a charging mode; when the high voltage generator is in a discharging mode, the main control module controls the discharging circuit to be started, the discharging circuit enters a discharging stage, the discharging circuit discharges the energy storage circuit in the discharging stage of the discharging circuit, the main control module obtains a real-time value of bus voltage DC output by the energy storage circuit through the sampling circuit, compares the real-time value of the bus voltage DC with a bus voltage comparison value DC _ LOW, and compares the real-time value of the current bus voltage with the real-time value of the previous bus voltage: if the real-time value of the bus voltage DC is greater than or equal to the bus voltage comparison value DC _ LOW, the high-voltage generator keeps a discharging mode, if the real-time value of the bus voltage DC is less than or equal to the bus voltage comparison value DC _ LOW, the main control module closes the discharging circuit at the moment, controls the charging circuit to be conducted, the high-voltage generator is switched from the discharging mode to the charging mode, in the process that the high-voltage generator keeps the discharging mode, if the real-time value of the current bus voltage is not reduced relative to the real-time value of the previous bus voltage, the discharging circuit is indicated to be damaged, at the moment, the main control module controls the charging circuit to be disconnected, the charging circuit is closed, controls the inverter circuit to stop working, the high-voltage generator stops working, and otherwise, the high-voltage generator continues to keep the discharging mode.

As shown in fig. 3, in this embodiment, the energy storage circuit includes a first energy storage capacitor group V1 and a second energy storage capacitor group V2, the first energy storage capacitor group V1 and the second energy storage capacitor group V2 respectively have an anode and a cathode, the cathode of the first energy storage capacitor group V1 is connected to the anode of the second energy storage capacitor group V2, a bus voltage DC is generated between the anode of the first energy storage capacitor group V1 and the cathode of the second energy storage capacitor group V2, the input boost circuit includes a first transformer T1, the first transformer T1 has a primary coil and a secondary coil, the charging circuit includes an electronic switch, a first resistor R1, a first diode D1 and a second diode D2, the first diode D1 and the second diode D2 are rectifier diodes, the sampling circuit includes a second resistor R2, a third resistor R3 and a fourth resistor R4, the inverter circuit includes four controllable switch devices, each controllable switch device has a control terminal, The controllable switch device controls the connection or disconnection of the first connection end and the second connection end thereof through signals accessed by the control end thereof, the four controllable switch devices are respectively called a first controllable switch device M1, a second controllable switch device M2, a third controllable switch device M3 and a fourth controllable switch device M4, the output boosting circuit comprises a first inductor L1, a first capacitor C1 and a second transformer T2, the second transformer T2 is provided with a primary coil and a secondary coil, two ends of the primary coil of the first transformer T1 are used for mains voltage, the electronic switch is provided with a first input end, a second input end, a first output end, a second output end and a control end, the first input end of the electronic switch is connected with one end of the secondary coil of the first transformer T1, the second input end of the electronic switch is connected with the other end of the secondary coil of the first transformer T1, a first output end of the electronic switch is connected with one end of a first resistor R1, a second output end of the electronic switch is connected with the connecting ends of a first energy storage capacitor group V1 and a second energy storage capacitor group V2, the other end of the first resistor R1 is respectively connected with the anode of a first diode D1 and the cathode of a second diode D2, the cathode of the first diode D1 is connected with the anode of a first energy storage capacitor group V1, the anode of a second diode D2 is connected with the cathode of a second energy storage capacitor group V2, one end of a second resistor R2 is connected with the anode of a first energy storage capacitor group V1, the other end of the second resistor R2 is connected with one end of a third resistor R3, the other end of a third resistor R3 is connected with one end of a fourth resistor R4, the other end of a fourth resistor R4 is connected with the cathode of a second energy storage capacitor group V2, the connecting ends of the third resistor R3 and the fourth resistor R4 are connected with the anode of a discharge module, and the discharge module is connected with the discharge module, A negative electrode and a control end, a control end of the discharge circuit is connected with the main control module, a positive electrode of the discharge circuit is connected with a positive electrode of the first energy storage capacitor group V1, a negative electrode of the discharge circuit is connected with a negative electrode of the second energy storage capacitor group V2, a control end of the first controllable switching device M1, a control end of the second controllable switching device M2, a control end of the third controllable switching device M3 and a control end of the fourth controllable switching device M4 are respectively connected with the main control module, a second connection end of the first controllable switching device M1 and a second connection end of the second controllable switching device M2 are respectively connected with a positive electrode of the first energy storage capacitor group V1, a first connection end of the third controllable switching device M3 and a first connection end of the fourth controllable switching device M4 are respectively connected with a negative electrode of the second energy storage capacitor group V2, a first connection end of the first controllable switching device M1, a second connection end of the third controllable switching device M3 and a second connection end 85L 1 are respectively connected with a negative electrode of the second energy storage capacitor group V2, the other terminal of the first inductor L1 is connected to one terminal of a first capacitor C1, the other terminal of the first capacitor C1 is connected to one terminal of the primary winding of a second transformer T2, the first connection terminal of the second controllable switching device M2, the second connection end of the third controllable switching device M3 is connected with the other end of the primary coil of the second transformer T2, an output voltage is output between two ends of the secondary coil of the second transformer T2, the feedback circuit collects the output voltage output between two ends of the secondary coil of the second transformer T2 and feeds the output voltage back to the main control module, the first controllable switching device M1 and the second controllable switching device M2 are used as a first group of controllable switching devices, the second controllable switching device M2 and the third controllable switching device M3 are used as a second group of controllable switching devices, and the main control module controls the internal on-off of the inverter circuit by controlling the first group of controllable switching devices and the second group of controllable switching devices to be alternately conducted.

In this embodiment, the four controllable switching devices are respectively implemented by MOS transistors or IGBT transistors, when the four controllable switching devices are respectively implemented by MOS transistors, gates of the MOS transistors serve as control ends of the controllable switching devices, sources and drains of the MOS transistors serve as first connection ends and second connection ends of the controllable switching devices, when the four controllable switching devices are respectively implemented by IGBT transistors, gates of the IGBT transistors serve as control ends of the controllable switching devices, and sources and drains of the IGBT transistors serve as first connection ends and second connection ends of the controllable switching devices.

Claims

1. A bus voltage control method of a high-voltage generator is characterized by comprising the following steps:

(1) setting control parameters in a main control module of the HIGH-voltage generator, wherein the control parameters comprise a first bus voltage limit value DC _ HIGH1, a second bus voltage limit value DC _ HIGH2, a standard bus voltage limit value DC _ HIGH, a bus voltage comparison value DC _ LOW and an OUTPUT voltage comparison value KV _ OUTPUT _ COMP, and recording the voltage boosting ratio of an input voltage boosting circuit of the HIGH-voltage generator as 1: n, the value range of the first bus voltage limiting value DC _ HIGH1 is 311N-342N volts, and the value range of the bus voltage comparison value DC _ LOW is (DC _ HIGH-10) to (DC _ HIGH-5) volts; the value of the second bus voltage limit value DC _ HIGH2 is smaller than the first bus voltage limit value DC _ HIGH1, the value of the OUTPUT voltage comparison value KV _ OUTPUT _ COMP is within the rated OUTPUT voltage range of the HIGH voltage generator, and the value of the second bus voltage limit value DC _ HIGH2 and the value of the OUTPUT voltage comparison value KV _ OUTPUT _ COMP simultaneously satisfy the following conditions: when the main control module of the high-voltage generator sets that the OUTPUT voltage is the minimum value of the rated OUTPUT voltage, the OUTPUT current is the minimum value of the rated OUTPUT current and the OUTPUT time is the shortest time of the rated OUTPUT time, the deviation between the actual OUTPUT voltage of the high-voltage generator and the set OUTPUT voltage is within 5 percent, and when the main control module of the high-voltage generator sets that the OUTPUT voltage is equal to the comparison value KV _ OUTPUT _ COMP of the OUTPUT voltage, the OUTPUT current is the maximum value of the rated OUTPUT current and the OUTPUT time is the longest time of the rated OUTPUT time, the deviation between the actual OUTPUT voltage of the high-voltage generator and the set OUTPUT voltage is within 5 percent;

(3) when the high-voltage generator is in a charging mode, the main control module controls the charging circuit to be conducted, the charging circuit enters a charging stage, the discharging circuit is in a closed state at the moment, the charging circuit charges the energy storage circuit in the charging stage of the charging circuit, the feedback circuit collects a real-time value of the output voltage of the output boosting circuit and feeds the real-time value back to the main control module, the main control module controls the internal on-off of the inverter circuit according to the real-time value of the output voltage of the output boosting circuit, the main control module starts timing from zero and obtains a real-time value of the bus voltage DC output by the energy storage circuit, the real-time value of the bus voltage DC is compared with a standard bus voltage limit value in real time, and R is reached when timing_H×C_{General assembly}Then, the real-time value of the current bus voltage DC is further compared with 0.63 × 311N volts: if the real-time value of the bus voltage DC is less than or equal to the standard bus voltage limit value, the high-voltage generator keeps a charging mode, if the real-time value of the bus voltage DC is greater than the standard bus voltage limit value, the main control module controls the charging circuit to be disconnected, the charging stage of the charging circuit is ended, the high-voltage generator is switched from the charging mode to a discharging mode, and if the timing of the main control module reaches R in the process that the high-voltage generator keeps the charging mode, the main control module keeps the charging mode_H×C_{General assembly}Wherein R is_HIndicating chargerTotal resistance of the electric circuit, C_{General assembly}The total capacitance value of the energy storage circuit is represented, and the real-time value of the current bus voltage DC is less than 0.63 × 311N volts, the charging circuit is damaged, the main control module controls the charging circuit to be disconnected, the charging circuit to be closed, controls the inverter circuit to stop working, the output booster circuit has no output voltage output, the high-voltage generator stops working, otherwise, the high-voltage generator continues to keep the charging mode; when the high voltage generator is in a discharging mode, the main control module controls the discharging circuit to be started, the discharging circuit enters a discharging stage, the discharging circuit discharges the energy storage circuit in the discharging stage of the discharging circuit, the main control module obtains a real-time value of the bus voltage DC output by the energy storage circuit, compares the real-time value of the bus voltage DC with a bus voltage comparison value DC _ LOW, and compares the real-time value of the current bus voltage with a real-time value of the previous bus voltage: if the real-time value of the bus voltage DC is greater than or equal to the bus voltage comparison value DC _ LOW, the high-voltage generator keeps a discharging mode, if the real-time value of the bus voltage DC is less than or equal to the bus voltage comparison value DC _ LOW, the main control module closes the discharging circuit at the moment, controls the charging circuit to be conducted, switches the high-voltage generator from the discharging mode to the charging mode, and in the process that the high-voltage generator keeps the discharging mode, if the real-time value of the current bus voltage is not reduced relative to the real-time value of the previous bus voltage, the damage of the discharging circuit is indicated, the main control module controls the charging circuit to be disconnected at the moment, closes the charging circuit, controls the inverter circuit to stop working, and stops working of the high-voltage generator, otherwise, the high-voltage generator continues to keep the discharging mode.