Pulse capacitor series-parallel switching system based on Monte Carlo method

Abstract

The invention discloses a pulse capacitor series-parallel switching system based on a Monte Carlo method, and the system comprises a pulse combination circuit which comprises a plurality of pulse circuits which are directly or indirectly connected with one another. Each pulse circuit comprises a pulse capacitor and a power switch which are connected in series; each power switch is controlled by a control signal to be switched on or switched off so as to change the connection mode of each pulse circuit in the pulse combination circuit; the control signal is generated by the controller by executing a Monte Carlo search algorithm according to the required output voltage and / or total capacitance capacity. According to the scheme, flexible control of the capacitor network is realized by adopting a Monte Carlo method, the technical problem that the capacitor capacity needs to be frequently changed in a vehicle relay test is solved, random switching of series connection and parallel connection of the pulse capacitor bank can be realized, a user only needs to input the required voltage or capacity, the operation is very convenient for the user, and the cost is reduced. Under the same circuit, more test requirements of users can be met more conveniently.

Description

Technical Field

[0001] The invention belongs to the technical field of power electronics, and in particular relates to a pulse capacitor series-parallel switching system based on a Monte Carlo method. Background Art

[0002] Pulse capacitors can charge and discharge quickly in a short period of time, releasing high-intensity pulse currents. Since pulse capacitors can provide instantaneous high-current pulses, they can simulate the pulse current conditions that relays may encounter in actual work. Therefore, they are widely used in relay testing, especially in automotive relay testing. For example, to test the arc resistance of relay contacts, the pulse current generated by the rapid discharge of pulse capacitors can be used to observe the performance of the contacts under such impacts and to test their life and reliability. In addition, pulse capacitors can also be used to test the response time of relays, and the pulses generated by capacitor discharge can be used to test whether the closing or opening of the relay meets the expected rapid response requirements, etc.

[0003] However, in relay testing scenarios, in order to test various scenarios and different relays, pulse capacitors with different output voltages and capacitances are required. In traditional test devices, users usually manually switch the series and parallel relationship of pulse capacitors to adjust the output or capacitance, which is cumbersome, difficult, and error-prone. Although there are operation guides, they usually only cover a few commonly used voltages and capacities, which are difficult to meet the diverse testing needs of users. Summary of the invention

[0004] The purpose of the present invention is to provide a pulse capacitor series-parallel switching system based on the Monte Carlo method to solve the above problems; Another object of the present invention is to provide a pulse capacitor series-parallel switching method based on the Monte Carlo method.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions: A pulse capacitor series-parallel switching system based on the Monte Carlo method includes a pulse combination circuit, wherein the pulse combination circuit includes a plurality of pulse circuits directly or indirectly connected to each other; Each pulse circuit includes a pulse capacitor and a power switch connected in series with each other; Each power switch is turned on or off by a control signal to change the connection mode of each pulse circuit in the pulse combination circuit; The control signal is generated by the controller by executing a Monte Carlo search algorithm according to the required output voltage and / or total capacitance.

[0006] In the above-mentioned pulse capacitor series-parallel switching system based on the Monte Carlo method, each pulse circuit includes a pulse capacitor, a power switch and a resistor connected in series with each other.

[0007] In the above-mentioned pulse capacitor series-parallel switching system based on the Monte Carlo method, the pulse capacitors of each pulse circuit have the same or different rated capacitance values; The resistors of each pulse circuit have the same or different resistance values; The pulse capacitors of the pulse circuits may have the same or different rated voltages.

[0008] In the above-mentioned pulse capacitor series-parallel switching system based on the Monte Carlo method, the pulse combination circuit is a two-dimensional rectangular network topology structure; Each power switch is turned on or off by a control signal to control the corresponding pulse circuit to be cut off from the circuit, or to be cut into the circuit alone, or to be connected in series or in parallel with other pulse circuits.

[0009] In the above-mentioned pulse capacitor series-parallel switching system based on the Monte Carlo method, the pulse combination circuit includes a plurality of parallel pulse circuits, each of which is formed by connecting a plurality of the pulse circuits in parallel; The parallel pulse circuits are sequentially connected in series to form the two-dimensional rectangular network topology structure; The parallel quantity and parallel objects of each parallel pulse circuit are controlled by controlling the power switch of each pulse circuit. If each pulse circuit has the same rated voltage, rated capacitance and resistance value, then the parallel object does not matter.

[0010] In the above-mentioned pulse capacitor series-parallel switching system based on the Monte Carlo method, each parallel pulse circuit is also connected in parallel with a short-circuit switch, and the short-circuit switch is turned on or off by the control signal; When the short-circuit switch is controlled to be turned on, the corresponding parallel pulse circuit is disconnected. When the short-circuit switch is controlled to be turned off, the parallel number and parallel object of the corresponding parallel pulse circuit are controlled by controlling the power switch of each pulse circuit.

[0011] A pulse capacitor series-parallel switching method based on the pulse capacitor series-parallel switching system based on the Monte Carlo method, the method comprising: Obtain the current input current, as well as the rated capacitance and rated voltage of each pulse circuit; generating a switch state matrix for the pulse combination circuit according to the circuit network of the pulse combination circuit; According to the circuit network of the pulse combination circuit, the input current, the rated capacitance value, the rated voltage, the resistance value of each pulse circuit, and the required output voltage and / or the total capacitance, a Monte Carlo search algorithm is executed to generate a strategy tree and update the switch state matrix, wherein the termination state of each path of the strategy tree is that the circuit network is turned on and cannot be further expanded, and each path splits a switch state matrix; Select the switch state matrix of the optimal strategy according to the strategy tree; The control signal is generated according to the selected switch state matrix.

[0012] In the above-mentioned pulse capacitor series-parallel switching method based on the Monte Carlo method, each element in the switch state matrix corresponds to a switch, and when the element is in one state, it indicates that the corresponding switch is in the on state, and when the element is in another state, it indicates that the corresponding switch is in the off state; The switch matrix includes the status information of each power switch, and when the parallel pulse circuit is also connected in parallel with a short-circuit switch, the switch matrix also includes the status information of the short-circuit switch.

[0013] In the above-mentioned Monte Carlo method-based pulse capacitor series-parallel switching method, the Monte Carlo search algorithm generates a strategy tree and selects the optimal strategy, specifically including: Use the UCB method to search and select the child node with the maximum UCB value, and search downward until you reach the leaf node at the bottom of the strategy tree; Expand the leaf nodes that have not reached the terminal state to expand one or more nodes. This is the expansion operation. According to the random strategy, simulate the on and off states of each switch until the circuit is turned on and a reward result is generated. This is a simulation operation. After the expansion is completed, the simulation is performed to simulate various conduction paths. According to the simulation results, update the reward values ​​of all nodes in reverse order from bottom to top; The above process is iterated to update the strategy tree until the specified time or computing power limit is reached, and the tree path with the highest reward value is selected as the optimal strategy according to the strategy tree.

[0014] In the above-mentioned Monte Carlo method-based pulse capacitor series-parallel switching method, the method further includes establishing a corresponding relationship table of input current, total capacitance, output voltage and control signal; When the same input current, total capacitance and output voltage are required, the corresponding control signal is extracted from the corresponding relationship table; Otherwise, the Monte Carlo search algorithm is executed to generate a control signal, and after the execution is completed, the corresponding relationship between the input current and the obtained total capacitance, output voltage and control signal is added to the corresponding relationship table.

[0015] The advantages of the present invention are: the Monte Carlo method is used to achieve flexible control of the capacitor network, which solves the technical problem of frequently changing the capacitor capacity during vehicle relay testing, and can realize arbitrary switching of the series and parallel connection of the pulse capacitor group to achieve the target voltage / capacity gear.

[0016] The user only needs to input the required voltage or capacity. The operation is very convenient for the user, and under the same circuit, it can more conveniently meet the user's more testing needs. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a system circuit diagram of an embodiment of a pulse capacitor series-parallel switching system based on the Monte Carlo method in the first embodiment of the present invention; Figure 2 is a system structure block diagram of a pulse capacitor series-parallel switching system based on the Monte Carlo method in the first embodiment of the present invention; Figure 3 is a schematic diagram of a strategy tree of a pulse capacitor series-parallel switching system based on a Monte Carlo method in Embodiment 1 of the present invention; Figure 4 It is a system circuit diagram of a pulse capacitor series-parallel switching system based on the Monte Carlo method of the present invention, taking a pulse combination circuit composed of four parallel pulse circuits as an example; Figure 5 yes Figure 4 Schematic diagram of the strategy tree corresponding to the circuit; Figure 6 is a system circuit diagram of a pulse capacitor series-parallel switching system based on the Monte Carlo method in the second embodiment of the present invention; Figure 7 This is a system circuit diagram of a pulse capacitor series-parallel switching system based on the Monte Carlo method in Example 2 of the present invention, taking a pulse combination circuit composed of four parallel pulse circuits as an example; Figure 8 yes Figure 7 Schematic diagram of the strategy tree corresponding to the circuit.

[0018] Reference numerals: pulse combination circuit 1 , parallel pulse circuit 11 , pulse circuit 2 , controller 3 . DETAILED DESCRIPTION

[0019] Embodiment 1

[0020] This solution provides a pulse capacitor series-parallel switching system based on the Monte Carlo method and provides a corresponding implementation method. Figure 1 and Figure 2 As shown, the system includes a pulse combination circuit 1, which includes a plurality of parallel pulse circuits 11, each of which is formed by connecting a plurality of pulse circuits 2 in parallel; each of the parallel pulse circuits 11 is connected in series in sequence to form a two-dimensional rectangular network topology, and each pulse circuit 2 includes a pulse capacitor, a power switch and a resistor connected in series. In this embodiment, the power switch uses a relay, but is not limited to a relay when put into use.

[0021] The relay is turned on and off by the control signal, thereby changing the connection mode of the pulse capacitor and outputting the required capacitor voltage and capacity. The output capacitor voltage and capacitance here refer to the entire pulse combination circuit 1, that is, the output voltage and total capacitance of the combination circuit. The control signal of the relay is generated by the controller 3 using the Monte Carlo search algorithm. Figure 1 The state of each relay in the circuit network shown is obtained by the state matrix V as follows: Different circuit networks will have different state matrices, which contain the state of each power switch in the circuit network. v ij The value corresponds to the state of a relay, "1" indicates that the relay is on, and "0" indicates that the relay is off.

[0022] The pulse capacitors of each pulse circuit 2 have the same or different rated capacitance values ​​as required, the resistors of each pulse circuit 2 have the same or different resistance values ​​as required, and the pulse capacitors of each pulse circuit 2 have the same or different rated voltages as required. The more different rated capacitances, resistance values, and rated voltages are, the more output voltages and capacitance capacity levels that can be achieved by the same circuit network, which can meet more diverse testing requirements.

[0023] The required voltage and capacitance are output by controlling the power switch of each pulse circuit 2 to control the parallel number and parallel object of each parallel pulse circuit 11.

[0024] like Figure 3 As shown, the method of generating a control signal using the Monte Carlo search algorithm in this scheme is as follows: During the execution of the algorithm, a strategy tree will be generated. The strategy tree has a root node and child nodes. The termination state of each path in the strategy tree is determined by whether the corresponding strategy tree can continue to expand and whether the circuit network has completed conduction. Conductivity does not necessarily mean termination, it may also continue to expand, but termination must be conduction. Different paths can have the same or different path lengths. In the end, there are several conduction paths, and there are several switch state matrices to choose from. The highest score is selected from these switch state matrices. The Monte Carlo search algorithm completes the selection algorithm, expansion algorithm, simulation algorithm, and back-propagation algorithm based on the capacitor state in the system through the strategy tree. Finally, the capacitor access strategy is selected according to the node reward value to generate the corresponding control signal.

[0025] The Monte Carlo search algorithm uses the UpperConfidenceBoundsUCB method for searching, which is given by the following formula: Among them, Q is the reward value of the node, N is the number of times the parent node is visited, n represents the number of times the current node is visited, and c is an adjustable parameter. In the selection algorithm, starting from the root node, select the child node with the largest value calculated by UCB, and search downward until the leaf node at the bottom of the tree is reached, waiting for the next operation. After reaching the leaf node, if the termination state has not been reached (the termination state refers to the judgment through the state matrix V that the pulse circuit network has been completed and cannot be expanded further), then this node is expanded to expand one or more nodes. Afterwards, based on the current state, the subsequent capacitor connection is simulated according to the random strategy until the circuit is completed and the reward value result is generated. The reward value is given by the following formula: In the formula, a is the voltage obtained, b is the obtained capacity, a 0 is the required voltage, b 0 is the required capacity. a, b According to the circuit network, that is, the connection relationship of each pulse circuit 2, and the current input current, the rated capacitance value, rated voltage, resistance value, etc. of each pulse circuit 2 connected to the circuit in the current state are calculated. This calculation is a conventional algorithm and will not be described in detail here. As can be seen from the formula, the reward value refers to the degree of closeness between the obtained voltage and capacity and the required voltage and capacity. The closer the closer, the greater the reward value, and vice versa. Here, taking the setting of the required voltage and capacity at the same time as an example, when only the voltage or capacity is set, the reward value can be calculated using the corresponding parameters. As shown in the subsequent example where a 10V output voltage is required, the capacitance is not specifically set. At this time, the formula is:

[0026] According to the simulation results, the reward values ​​of all nodes are updated in reverse from bottom to top.

[0027] When the specified time or computing capacity limit is reached, the algorithm stops, the node with the largest reward value is selected to execute and end the algorithm, and the state information V1 at this time is output. The access strategy of the capacitor is selected according to the state, and the corresponding control signal is generated.

[0028] This solution proposes a pulse capacitor series-parallel switching system based on the Monte Carlo method. The basic principle of this solution is as follows: The Monte Carlo method uses exploration and utilization to solve the problem of quickly obtaining the required voltage and capacity in the pulse capacitor series-parallel switching system. By exploring and moving in the unknown direction, new circuit connection methods are constantly tried to continuously obtain better strategies. At the same time, the experience gained from previous attempts is used to obtain a reliable capacitor access strategy selection. The final optimal capacitor access strategy is obtained through multiple simulations and attempts. The user only needs to set the required output voltage and / or capacitance.

[0029] The following is an example of a pulse combination circuit 1 composed of four parallel pulse circuits 11: like Figure 4 As shown, in this example, the rated voltages of the four parallel pulse circuits 11 are respectively , the pulse capacitor capacity is 1C, and the user needs to achieve a 10V voltage output and obtain the maximum capacitance. The initial state matrix of the capacitor network can be

[0030] The generated strategy tree is as follows Figure 5 As shown in the figure, after the selection algorithm, expansion algorithm, simulation algorithm and back propagation algorithm, when the computing power limit is reached, the algorithm stops and the node with the largest reward value is selected for execution. The state information V1 at this time is output as The capacity reached is 2 / 3C.

[0031] The state of each switch can be obtained according to the state matrix V1, and a control signal is output to each switch respectively to complete the series-parallel switching of the pulse capacitor.

[0032] This solution uses the Monte Carlo method to achieve series-parallel switching of pulse capacitors, which can realize arbitrary series-parallel switching of pulse capacitor groups, flexibly and reliably output the required voltage and capacity, and solve the shortcomings of traditional capacitor groups such as frequent manual adjustment or limited testing capabilities.

[0033] Embodiment 2

[0034] like Figure 6 As shown, this embodiment is similar to the first embodiment, except that in this embodiment, each parallel pulse circuit 11 is further connected in parallel with a short-circuit switch, that is, Figure 6 S17, S27, S37, and the remaining S11-S16, S21-S26, S31-S36 are all the power switches, and the short-circuit switches are also controlled to be turned on or off by the control signal. The switch matrix contains the status information of each power switch and short-circuit switch.

[0035] When the short-circuit switch is controlled to be turned on, the corresponding parallel pulse circuit 11 is disconnected. When the short-circuit switch is controlled to be turned off, the parallel number and parallel object of the pulse circuit 2 of the corresponding parallel pulse circuit 11 are controlled by controlling the power switch of each pulse circuit 2.

[0036] The following also uses a pulse combination circuit 1 composed of four parallel pulse circuits 11 as an example: like Figure 7 As shown, in this example, the rated voltages of the four parallel pulse circuits 11 are respectively , the user needs to achieve a 2C capacitor capacity, and the initial state matrix of the capacitor network can be The generated strategy tree is as follows Figure 8 As shown in the figure, after the selection algorithm, expansion algorithm, simulation algorithm and back propagation algorithm, when the computing power limit is reached, the algorithm stops and the node with the largest reward value is selected for execution. The state information V1 at this time is output as The capacity reaches 2C and the voltage is 5V.

[0037] The state of each switch can be obtained according to the state matrix V1, and a control signal is output to each switch respectively to complete the series-parallel switching of the pulse capacitor.

[0038] Embodiment 3

[0039] This embodiment is similar to the first embodiment, except that the series-parallel control method of this embodiment further includes:

[0040] Establish a corresponding relationship table of input current, total capacitance, output voltage and control signal, as shown in Table 1 below; When the same input current, total capacitance and output voltage are required, the corresponding control signal is extracted from the corresponding relationship table; Otherwise, the Monte Carlo search algorithm is executed to generate a control signal, and the control signal is preferably turned on at the highest voltage. After the execution is completed, the corresponding relationship between the input current and the total capacitance, output voltage and control signal obtained is added to the corresponding relationship table.

[0041] Table 1 Correspondence table

[0042] That is to say, during the user's use, the pre-stored table belonging to the customer is generated and improved according to the customer's needs. When the user needs the same output voltage or capacitance, the control signal can be quickly extracted without calculation and optimal strategy selection. At the same time, when the user has a new output voltage or capacitance test requirement, the control signal is automatically calculated and generated by executing the Monte Carlo search algorithm, and the control signal is used to further improve the pre-stored table. In this way, both speed and diversity can be taken into account, and the output voltage and output capacity potential of the pulse capacitor series-parallel switching system can be deeply explored.

[0043] The specific embodiments described herein are merely examples of the spirit of the present invention. Those skilled in the art may make various modifications or additions to the specific embodiments described or replace them in similar ways, but they will not deviate from the spirit of the present invention or exceed the scope defined by the appended claims.

[0044] Although the pulse combination circuit 1, parallel pulse circuit 11, pulse circuit 2, controller 3 and other terms are often used in this article, the possibility of using other terms is not excluded. These terms are used only to more conveniently describe and explain the essence of the present invention; interpreting them as any additional restrictions is contrary to the spirit of the present invention.

Claims

1. A pulse capacitor series-parallel switching system based on the Monte Carlo method, comprising a pulse combination circuit (1), characterized in that: The pulse combination circuit (1) comprises a plurality of pulse circuits (2) directly or indirectly connected to each other; Each pulse circuit (2) comprises a pulse capacitor and a power switch connected in series with each other; Each power switch is turned on or off by a control signal to change the connection mode of each pulse circuit (2) in the pulse combination circuit (1); The control signal is generated by the controller (3) by executing a Monte Carlo search algorithm according to the required output voltage and / or total capacitance.

2. The pulse capacitor series-parallel switching system based on the Monte Carlo method according to claim 1, characterized in that: Each pulse circuit (2) comprises a pulse capacitor, a power switch and a resistor which are connected in series.

3. The pulse capacitor series-parallel switching system based on the Monte Carlo method according to claim 2, characterized in that: The pulse capacitors of the pulse circuits (2) have the same or different rated capacitance values; The resistors of each pulse circuit (2) have the same or different resistance values; The pulse capacitors of the pulse circuits (2) have the same or different rated voltages.

4. The pulse capacitor series-parallel switching system based on the Monte Carlo method according to claim 3 is characterized in that: The pulse combination circuit (1) presents a two-dimensional rectangular network topology structure; Each power switch is turned on or off by a control signal to control the corresponding pulse circuit (2) to be cut off from the circuit, or to be cut into the circuit alone, or to be connected in series or in parallel with other pulse circuits.

5. The pulse capacitor series-parallel switching system based on the Monte Carlo method according to claim 4, characterized in that: The pulse combination circuit (1) comprises a plurality of parallel pulse circuits (11), each of which is formed by connecting a plurality of the pulse circuits (2) in parallel; The parallel pulse circuits (11) are sequentially connected in series to form the two-dimensional rectangular network topology structure; The parallel quantity and parallel object of the pulse circuits (2) of each parallel pulse circuit (11) are controlled by controlling the power switch of each pulse circuit (2).

6. The pulse capacitor series-parallel switching system based on the Monte Carlo method according to claim 5, characterized in that: Each parallel pulse circuit (11) is also connected in parallel with a short-circuit switch, and the short-circuit switch is turned on or off by the control signal; When the short-circuit switch is controlled to be turned on, the corresponding parallel pulse circuit (11) is disconnected; when the short-circuit switch is controlled to be turned off, the parallel number and parallel object of the pulse circuit (2) of the corresponding parallel pulse circuit (11) are controlled by controlling the power switch of each pulse circuit (2).

7. A pulse capacitor series-parallel switching method of a pulse capacitor series-parallel switching system based on the Monte Carlo method according to any one of claims 1 to 6, characterized in that: The method includes: Obtain the current input current, as well as the rated capacitance and rated voltage of each pulse circuit (2); generating a switch state matrix for the pulse combination circuit (1) according to the circuit network of the pulse combination circuit (1); According to the circuit network of the pulse combination circuit (1), the input current, the rated capacitance value, the rated voltage, the resistance value of each pulse circuit (2), and the required output voltage and / or the total capacitance, a Monte Carlo search algorithm is executed to generate a strategy tree and update the switch state matrix, wherein the termination state of each path of the strategy tree is that the circuit network is turned on and cannot be further expanded, and each path splits a switch state matrix; Select the switch state matrix of the optimal strategy according to the strategy tree; The control signal is generated according to the selected switch state matrix.

8. The pulse capacitor series-parallel switching method based on the Monte Carlo method according to claim 7, characterized in that: Each element in the switch state matrix corresponds to a switch. When the element is in one state, it indicates that the corresponding switch is in the on state. When the element is in another state, it indicates that the corresponding switch is in the off state. The switch matrix contains status information of each power switch, and when the parallel pulse circuit (11) is also connected in parallel with a short-circuit switch, the switch matrix also contains status information of the short-circuit switch.

9. The method for switching pulse capacitors in series and in parallel based on the Monte Carlo method according to claim 8, characterized in that: The Monte Carlo search algorithm generates a strategy tree and selects the optimal strategy, including: Use the UCB method to search and select the child node with the maximum UCB value, and search downward until you reach the leaf node at the bottom of the strategy tree; Expand the leaf nodes that have not reached the terminal state to expand one or more nodes; According to the random strategy, simulate the on and off states of each switch until the circuit is turned on and a reward result is generated; According to the simulation results, update the reward values ​​of all nodes in reverse order from bottom to top; The above process is iterated to update the strategy tree until the specified time or computing power limit is reached, and the tree path with the highest reward value is selected as the optimal strategy according to the strategy tree.

10. The pulse capacitor series-parallel switching method based on the Monte Carlo method according to claim 8, characterized in that: The method further includes establishing a corresponding relationship table of input current, total capacitance, output voltage and control signal; When the same input current, total capacitance and output voltage are required, the corresponding control signal is extracted from the corresponding relationship table; Otherwise, the Monte Carlo search algorithm is executed to generate a control signal, and after the execution is completed, the corresponding relationship between the input current and the obtained total capacitance, output voltage and control signal is added to the corresponding relationship table.

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