Driving circuit for accelerating actuation of relay
By introducing an energy storage capacitor and a switching transistor structure into the electromagnetic relay drive circuit, the relay coil voltage is increased, solving the problem of slow electromagnetic relay engagement speed and achieving rapid engagement without increasing cost.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- SICON CHAT UNION ELECTRIC CO LTD
- Filing Date
- 2025-04-08
- Publication Date
- 2026-05-15
AI Technical Summary
Existing electromagnetic relays cannot meet the fast action requirement of 2ms-3ms at the AC output end of UPS and in EPO passive dry contact scenarios, and replacing them with solid-state relays would increase equipment costs.
The drive circuit, composed of an energy storage capacitor, a tetrode, a first switching transistor, and a second switching transistor, increases the excitation current by doubling the voltage of the relay coil to accelerate the pull-in speed.
Without increasing equipment costs, the relay's pull-in time is significantly shortened to meet the requirements for rapid action.
Smart Images
Figure CN224248553U_ABST
Abstract
Description
Technical Field
[0001] This disclosure relates to the field of circuit technology, and in particular to a drive circuit for accelerating the engagement of a relay. Background Technology
[0002] The working principle of an electromagnetic relay with mechanical contacts is as follows: when a certain voltage is applied across the coil, a certain current flows through the coil, thereby generating an electromagnetic effect. Under the attraction of electromagnetic force, the armature overcomes the tension of the return spring and is attracted to the iron core, thereby driving the moving contact of the armature to engage with the stationary contact. The engagement time is approximately 7-10 ms.
[0003] When applying electromagnetic relays to the AC output of UPS and EPO passive dry contact scenarios, the relay is required to complete the action within 2ms-3ms after the signal is sent. This action time is far from meeting the requirements. Solid-state relays can be used to replace electromagnetic relays to solve the above problem, but this will increase the equipment cost. Utility Model Content
[0004] This disclosure provides a driving circuit for accelerating relay engagement, which can increase the engagement speed of the relay without increasing equipment costs.
[0005] This disclosure provides a driving circuit for accelerating relay engagement, including an energy storage capacitor, a fourth diode, a first switching transistor, a first resistor, and a second switching transistor.
[0006] The control terminal of the second switch is used to connect to the controller. The first terminal of the second switch is grounded, and the second terminal of the second switch is connected to the control terminal of the first switch. The first terminal of the first switch is connected to a first power supply, and the second terminal of the first switch is connected to the first terminal of the first resistor. The second terminal of the first resistor is grounded.
[0007] The anode of the fourth diode is connected to the first power supply, the cathode of the fourth diode is connected to the positive terminal of the energy storage capacitor, and the negative terminal of the energy storage capacitor is connected to the first terminal of the first resistor.
[0008] The positive terminal of the energy storage capacitor is used to connect to the first terminal of the relay coil, and the second terminal of the second switching transistor is used to connect to the second terminal of the relay coil.
[0009] In one exemplary embodiment of this disclosure, a third resistor is provided between the second terminal of the second switching transistor and the control terminal of the first switching transistor. The driving circuit for the acceleration relay to engage further includes a second resistor, the first terminal of which is connected to a first power supply, and the second terminal of which is connected to the control terminal of the first switching transistor.
[0010] In one exemplary embodiment of this disclosure, the driving circuit for accelerating the engagement of the relay further includes a third diode, the cathode of which is connected to the control terminal of the first switching transistor, and the anode of which is connected to a first power supply.
[0011] In one exemplary embodiment of this disclosure, a first diode and a second diode are disposed between the second terminal of the first switching transistor and the first terminal of the first resistor.
[0012] The anode of the first diode is connected to the second terminal of the first switching transistor, the cathode of the first diode is connected to the anode of the second diode, and the cathode of the second diode is connected to the first terminal of the first resistor.
[0013] In one exemplary embodiment of this disclosure, a fifth resistor is connected in parallel between the control terminal and the first terminal of the second switch.
[0014] In one exemplary embodiment of this disclosure, a first capacitor is connected in parallel between the control terminal and the first terminal of the second switch.
[0015] In one exemplary embodiment of this disclosure, a TVS diode is connected in parallel between the first and second terminals of the second switching transistor.
[0016] The driving circuit for accelerating relay engagement provided in this embodiment has the following working principle and beneficial effects:
[0017] In this embodiment of the present disclosure, when the controller outputs a low-level signal to the control terminal of the second switching transistor, both the second and first switching transistors are turned off, the coil of the relay is not energized, and the first power supply charges the energy storage capacitor through the fourth diode. The voltage across the energy storage capacitor is the voltage of the first power supply.
[0018] When the controller outputs a high-level signal to the control terminal of the second switching transistor, both the second and first switching transistors are turned on, the relay coil is energized, and the first power supply is connected to the negative terminal of the energy storage capacitor through the first switching transistor. The voltage at the negative terminal of the energy storage capacitor is equal to the voltage of the first power supply. Since the voltage across the energy storage capacitor is the voltage of the first power supply, the voltage at the positive terminal of the energy storage capacitor is twice the voltage of the first power supply. At this time, since the voltage at the cathode of the fourth diode is higher than the voltage at the anode, the fourth diode is turned off. The voltage at the positive terminal of the energy storage capacitor is applied to the first terminal of the relay coil, and the second terminal of the relay coil is grounded. That is, twice the voltage of the first power supply is applied across the relay coil.
[0019] After the relay is energized, as the energy in the storage capacitor is depleted, the fourth diode turns on, and the first power supply provides the rated voltage to the relay coil, maintaining the relay's energization.
[0020] Therefore, the embodiments of this disclosure can increase the excitation voltage across the relay coil, thereby increasing the excitation current and accelerating the relay's closing speed. Attached Figure Description
[0021] To more clearly illustrate the technical solutions in the embodiments of this disclosure, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this disclosure. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0022] Figure 1 This is a schematic diagram of the drive circuit for accelerating relay engagement provided in an embodiment of this disclosure. Detailed Implementation
[0023] To enable those skilled in the art to better understand this solution, the technical solutions in the embodiments of this solution will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this solution, not all of them. Based on the embodiments of this solution, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this solution.
[0024] The term "comprising" and any other variations thereof in the specification, claims, and accompanying drawings of this invention mean "including but not limited to," and are intended to cover a non-exclusive inclusion, not limited to the examples listed herein. Furthermore, the terms "first" and "second," etc., are used to distinguish different objects, not to describe a specific order.
[0025] The implementation of this disclosure will be described in detail below with reference to the specific accompanying drawings:
[0026] Figure 1 This is a schematic diagram of a drive circuit for accelerating the engagement of a relay, provided as an embodiment of this disclosure. (Refer to...) Figure 1 The drive circuit for accelerating relay engagement includes an energy storage capacitor E1, a fourth diode D4, a first switch Q1, a first resistor R1, and a second switch Q2.
[0027] The control terminal of the second switch Q2 is used to connect to the controller. The first terminal of the second switch Q2 is grounded, and the second terminal of the second switch Q2 is connected to the control terminal of the first switch Q1. The first terminal of the first switch Q1 is connected to the first power supply DC24V, and the second terminal of the first switch Q1 is connected to the first terminal of the first resistor R1. The second terminal of the first resistor R1 is grounded.
[0028] The anode of the fourth diode D4 is connected to the first power supply DC24V, the cathode of the fourth diode D4 is connected to the positive terminal of the energy storage capacitor E1, and the negative terminal of the energy storage capacitor E1 is connected to the first terminal of the first resistor R1.
[0029] The positive terminal of the energy storage capacitor E1 is used to connect to the first terminal of the relay coil, and the second terminal of the second switching transistor Q2 is used to connect to the second terminal of the relay coil.
[0030] In this embodiment, when the controller outputs a low-level signal to the control terminal of the second switch Q2, both the second switch Q2 and the first switch Q1 are turned off, the relay coil is not energized, and the first power supply DC24V charges the energy storage capacitor E1 through the fourth diode D4. The voltage across the energy storage capacitor E1 is the voltage of the first power supply DC24V.
[0031] When the controller outputs a high-level signal to the control terminal of the second switch Q2, both the second switch Q2 and the first switch Q1 are turned on, the relay coil is energized, and the first power supply DC24V is connected to the negative terminal of the energy storage capacitor E1 through the first switch Q1. The voltage at the negative terminal of the energy storage capacitor E1 is equal to the voltage of the first power supply DC24V. Since the voltage across the energy storage capacitor E1 is the voltage of the first power supply DC24V, the voltage at the positive terminal of the energy storage capacitor E1 is twice the first power supply voltage (i.e., 48V). At this time, since the voltage at the cathode of the fourth diode D4 is higher than the voltage at the anode, the fourth diode D4 is turned off. The voltage at the positive terminal of the energy storage capacitor E1 is applied to the first terminal RELAYV+ of the relay coil, and the second terminal RELAYV- of the relay coil is grounded. That is, twice the first power supply voltage is applied across the relay coil.
[0032] After the relay is energized, as the energy in the storage capacitor E1 is depleted, the fourth diode D4 turns on, and the first power supply DC24V provides the rated voltage to the relay coil, keeping the relay energized.
[0033] Therefore, the embodiments of this disclosure can increase the excitation voltage across the relay coil, thereby increasing the excitation current and accelerating the relay's closing speed.
[0034] The controller can be a microcontroller such as a single-chip microcomputer, DSP, or ARM, which are commonly used in the market. No specific restrictions are made here.
[0035] In one exemplary embodiment of this disclosure, a third resistor R3 is provided between the second terminal of the second switch Q2 and the control terminal of the first switch Q1. The driving circuit for accelerating the relay to engage also includes a second resistor R2, the first terminal of which is connected to the first power supply DC24V, and the second terminal of which is connected to the control terminal of the first switch Q1.
[0036] In this embodiment, the first switching transistor Q1 is specifically a PNP transistor. When the second switching transistor Q2 is turned on, the second resistor R2 and the third resistor R3 are connected in series between the first power supply DC24V and ground to form a voltage divider circuit. The second end of the second resistor R2 is connected to the control terminal (i.e., the base) of the first switching transistor Q1, and the first power supply DC24V is connected to the first terminal (i.e., the emitter) of the first switching transistor Q1. The emitter voltage of the first switching transistor Q1 is greater than the base voltage, and the first switching transistor Q1 is turned on.
[0037] In one exemplary embodiment of this disclosure, the driving circuit for accelerating the engagement of the relay further includes a third diode D3, the cathode of which is connected to the control terminal of the first switching transistor Q1, and the anode of which is connected to the first power supply DC24V.
[0038] In this embodiment, the third diode D3 is connected in parallel between the first terminal and the second terminal of the first switch Q1 to clamp the voltage between the first terminal and the second terminal of the first switch Q1, thereby preventing the first switch Q1 from being damaged due to excessive voltage.
[0039] In one exemplary embodiment of this disclosure, a first diode D1 and a second diode D2 are disposed between the second terminal of the first switching transistor Q1 and the first terminal of the first resistor R1.
[0040] The anode of the first diode is connected to the second terminal of the first switching transistor, the cathode of the first diode is connected to the anode of the second diode, and the cathode of the second diode is connected to the first terminal of the first resistor.
[0041] In this embodiment, after the energy storage capacitor E1 is depleted, in order to avoid the appearance of voltages with opposite polarity on the energy storage capacitor E1, which could cause a short circuit and damage the device, a first diode D1 and a second diode D2 can be connected in series at the second terminal of the first switching transistor Q1 and the first terminal of the first resistor R1 to reduce the voltage at the negative terminal of the energy storage capacitor E1 and ensure that the voltage across the energy storage capacitor is positive.
[0042] Theoretically, the voltage drop of the first switch Q1 plus the voltage drop of the first diode D1 can satisfy the requirement that the negative voltage of the energy storage capacitor E1 is less than the positive voltage. For safety, this embodiment uses two diodes, namely the first diode D1 and the second diode D2.
[0043] As can be seen from the above, the arrangement of the first diode D1 and the second diode D2 in this embodiment can reduce the voltage at the negative terminal of the energy storage capacitor E1, thereby ensuring that the voltage across the energy storage capacitor is positive.
[0044] In one exemplary embodiment of this disclosure, a fifth resistor R5 is connected in parallel between the control terminal and the first terminal of the second switch Q2.
[0045] In this embodiment, the fifth resistor R5 can provide a stable DC voltage to the control terminal of the second switch Q2, ensuring the stable operation of the second switch Q2.
[0046] In one exemplary embodiment of this disclosure, a first capacitor C1 is connected in parallel between the control terminal and the first terminal of the second switch Q2.
[0047] In this embodiment, the first capacitor C1 can filter out the high-frequency interference signal at the control terminal of the second switch Q2, thereby making the signal at the control terminal of the second switch Q2 smoother and more stable.
[0048] In one exemplary embodiment of this disclosure, a TVS diode is connected in parallel between the first and second terminals of the second switch Q2.
[0049] In this embodiment, a large current change may occur during the turn-on and turn-off of the second switch, thereby triggering a surge voltage. The TVS diode can absorb this surge energy, preventing it from damaging the second switch and other circuit components.
[0050] The above embodiments are only used to illustrate the technical solutions of this disclosure, and are not intended to limit it. Although this disclosure has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this disclosure.
Claims
1. A driving circuit for accelerating relay engagement, characterized in that, It includes an energy storage capacitor, a fourth diode, a first switching transistor, a first resistor, and a second switching transistor. The control terminal of the second switch is used to connect to the controller. The first terminal of the second switch is grounded, and the second terminal of the second switch is connected to the control terminal of the first switch. The first terminal of the first switch is connected to a first power supply, and the second terminal of the first switch is connected to the first terminal of the first resistor. The second terminal of the first resistor is grounded. The anode of the fourth diode is connected to the first power supply, the cathode of the fourth diode is connected to the positive terminal of the energy storage capacitor, and the negative terminal of the energy storage capacitor is connected to the first terminal of the first resistor. The positive terminal of the energy storage capacitor is used to connect to the first terminal of the relay coil, and the second terminal of the second switching transistor is used to connect to the second terminal of the relay coil.
2. The driving circuit for accelerating relay engagement as described in claim 1, characterized in that, A third resistor is provided between the second terminal of the second switching transistor and the control terminal of the first switching transistor. The driving circuit for the acceleration relay to engage also includes a second resistor. The first terminal of the second resistor is connected to the first power supply, and the second terminal of the second resistor is connected to the control terminal of the first switching transistor.
3. The driving circuit for accelerating relay engagement as described in claim 1, characterized in that, It also includes a third diode, the cathode of which is connected to the control terminal of the first switching transistor, and the anode of which is connected to the first power supply.
4. The driving circuit for accelerating relay engagement as described in claim 1, characterized in that, A first diode and a second diode are disposed between the second terminal of the first switching transistor and the first terminal of the first resistor. The anode of the first diode is connected to the second terminal of the first switching transistor, the cathode of the first diode is connected to the anode of the second diode, and the cathode of the second diode is connected to the first terminal of the first resistor.
5. The driving circuit for accelerating relay engagement as described in claim 1, characterized in that, A fifth resistor is connected in parallel between the control terminal and the first terminal of the second switch.
6. The driving circuit for accelerating relay engagement as described in claim 1, characterized in that, A first capacitor is connected in parallel between the control terminal and the first terminal of the second switch.
7. The driving circuit for accelerating relay engagement as described in claim 1, characterized in that, A TVS diode is connected in parallel between the first and second terminals of the second switching transistor.